Studies on Development of Respiratory Organ in Middle and Later Stages of Prenatal Life of Korean Fetus

The developmental feature of the respiratory organ including the larynx, trachea, bronchi, and lungs in middle and later stages of the fetal period has been studied by means of measuring the various diameters and weighing some of the parts of the organ. The materials used for present observation are a sum of 395 cases of the Korean fetuses including 202 cases of male and 193 cases of female aged from the 4th month to the term of the prenatal life. 1. Of the larynx antero-posterior diameter of the upper part is longer than that of the lower. The antero一 posterior diameters of the larynx are shown a reiatively rapid growth with the time until the 6 th month, are followed by a relatively slow increase thereafter, and are rapidly increased again at the 10th fetal month. 2. Of the larynx the transverse diameter of the upper part is longer than that of the lower part by the 4th month. The transverse diameters are shown a rapid increase until the 5th, are followed by a relatively slow increase with the time until the 8th, and are rapidly increased again thereafter. 3. Of the larynx the height on the anterior part is longer than that of the posterior part by the 4th month. The heights of both the anterior and posterior parts are shown a rapid increase until the 5th, are followed by slow one thereafter, and are rapidly increased again at the 10th mont

Studies on the Development of the Cerebral Sulci of Korean Fetus

The development of the cerebral sulic of 364 (c; 189. ~ 175) Korean fetuses older than four month of age vvere observed. 1) I recognized the transitnry sulci were true natural which fully dervloped during 4th month and disappeared in the middle of 6th month (22nd week), 2) The principal cerebral sulic began to appear during 5th month and all of them appeared until 7th or 8th month. 3) Even the small accessory cerebral sulci began to appear until 8th month. 4) The time of appearance and the grade of development were very different on each case and there were differences of two or three months. 5) The left posterior ramus of the lateral fissure was longer than the right one on an average and in each case, very frequently, the left remus was longer than the right one. 6) There were no sexual differences in the development of the cerebral sulci

Studies on Elbow Joint of Korean Fetus during Middle and Later Stages of Fetal Life

The developmental feature of the elbow joint in the middle and later stages of the fetal period has been studied by measuring over 27 items on the articular capsule with its accessory ligaments and participating bone ends from 365 cases 081 cases of male and 184 cases of female) of the Korean fetuses aged from the 4th month to the term of the fetal life. 1. By the 4th month the length of the posterior part of the joint capsule is longer than that of the anterior part, as in that of the adult. The higher monthly developmental rate, however, is detectable on the length of anterior part of the joint capsule. 2. The medial collateral ligament is longer at the 10th month. as in the adult. Until 9th month, however, none of the practical difference on the length between the medial and lateral collateral ligaments is observed. 3. The growths of the various parts of the participating bone ends are relatively rapid until the 6th month. and become slow until the 8th. and relatively slower thereafter. The widths of them. however, show again a tendency of relatively rapid growth at the 10th fetal month. 4. The indices of the 13 important measurements to the body length are stabilized after the 8th month. In other words, after the 8th month the velocities of the growth of the various measurements are silmilar to that of the body length. 5. None of the sexual difference was found in present observation

Studies on the Cytoarchitectonics of the Angular Gyrus (Brodmann s Area of 39) of the Korean Cerebral Hemisphere

This investigation is a study on the cytoarchitec一 tonics of the wall of the cerebral sulcus in the angular gyrus (Brodmann s arca of 39) of 152 Korean brains (86 of male, 66 of fcmale) from the newborns to the adults. The thickness of the total cortex and each cortical layer, the relative neuron density and the relative glia density in C100U) 3 of each cortical layer and the relative total neuron and glia densities of the cortex were observed and the results were summerized as follows; 1. The mean thickness of the cortex in the 0-1 year group was 81% of the adult and it increased very rapidly during 2-5 years and it was thick as the adult cortex. In the 6-10 year groups it was maximum thick and thereafter it decreased gradually. The mean thickness of the cortex increased rapidly until the 700-800g stage of the brain weight and increased slowly until the 1. 1애- 1. 1999 stage of the brain weight and during this stage it was thick as the adult cortex. Thereafter it had a tenducy of slow increasing as the brain weight increased. 2, The relative neuron density was highest in the 0-1 year group and it decreased very rapidly in the 2-5 year group and it decreased slowly until the 11-15 year groups and at this time it is eaqual as the adult mean value. Thereafter it was relatively stable but it had a tendency to increase in old age. As the relation between the neuron density and the brain weight, it was highest in 300 많)()g stage of brain weight and it decreased rapidly until the brain weig ht was 500-700g stage and it drecreased slowly until the brain weight was 1. 1000-1.200g stage and in this stage it became eaqual as the adult mean value. Thereafter it had a tendevcy to decrea~e slowly as the brain weight increased. The mean value of the neuron density of the adult was 499-559. 3. The relative glia density was high in the 0-1 year group and it decreased rapidly in the 2-5 year group and was minimum value which was lower than the adult mean value, and thereafter it increased gradually as the age increased. The mean value of the relative glia density of the adult was 558-641 which is higher than that of the ad비t neuron density(4~뽕559). During the 300-500g stage of the brain weight the relative glia density was high and it decreased gradually to the minimum value (465-521) until the 1. 100- 1. 200g stage of the brain weight and thereafter it increased gradully as the brain weight increased. 4. The neuron density and glia density had no sexual defference and left-right lifference

Studies on the Development and Cytoarchitectonics of the Premotor Area (Brodmann's Area 6) of the Cerebral Cortex of the Fetus

The authors studied on the development and cytoarchitectonics of the cerebral cortex in the Brodmann's area of (j in the 119 (male 64, female 55) Korean fetal brains and summarized the result as follows; 1. The thickness of the cerebral cortex was very thin of 0.21mm at the f()Urth month of fetal age and increased very rapidly in the fifth and sixth month, slowly from the seventh to the ninth month, and very rapidly again in the tenth month. As to the relation between brain weight and the thickness of the cerebral cortex, the thicknes of the cerebral cortex was very thin under 50gm of brain weight; increased very rapidly until the brain weight gaind to 101-150gm. thereafter increased slowly to 400gm. and increased very rapidly again over 401gm of the brain weight. 2. The differentiation of the lamination of the cerebral cortex began a diverge in the sixth fetal month, and the lamination of the cortex occurred almost completely at the seventh fetal month. As the relation of the defferentiation of the cerebral cortex with the brain weight, it began a diverge from 51gm to 100gm of the brain weight. but there might be an individnal difference of Ianination. 3. The relative cell density of the cerebral cortex cannot be measured under the fifth month of fetal age. The relative cell density of the cerebral cortex was very high in the sixth and the seventh fetal month and thereafter it decreased gradually as the increase of fetal age. As the relation of the relative cell density with the brain weight, the relative cell density was very high up to 150gm of the brain weight and thereafter it decreased gradually as the increase of the brain weight. The absolute cell density was found the resemblance of the relative cell density. 4. The nerve cells of the fetal cortex might be increased very rapidly up to the seventh month of fetal age and thereafter the number of the nerve cells of the cortex might be stabilized. 5. Thickness of the cortex. the relative cell density and absolute cell density of the cerebral cortex had almost no sexual difference

Studies on the Cytoarchitectonics of the Frontal Pole Area(Brodmann's Area of 10) of the Korean Cerebral Hemisphere

This investigation is a study on the cytoarchitectonics of the wall of the cerebral sulcus in the frontal pole areas of 145 Korean brains(85 brains of the male, from the newborn to the age of 85, 64 brains of the female, from the newborn to the age of 61). The thickness of the total cortex and each cortical layer, the relative neuron density and the relative glia density in (IOO,u)' of each cortical layer and the relative total neuron and glia densities of the cortex were observed and the results were summerized as follows: 1. The mean thickness of the cortex in the 0-1 year group was 1.58-1. 67 mm. Which was 81.2% of the adult cortex thickness and increased to 1.801. 90 mm in the 2-5 year group which was 92.2% of the adult and thereafter it increased to the adult mean thickness in the 11-15 year group, and thereafter it was relativery stable. The mean thickness of the adult cortex was 2.01mm. The thickness of the cortex increased gradually as the brain weight increased to 1, 400gms and thereafter it became to decrease. 2. The highest neuron density in the 0-1 year group decreased rapidly to the adult mean value in the 11-15 year group and thereafter it was relatively stable. The mean neuron density of the adult cortex was 670-687. As the relationship between the neuron density and the brain weight, it was highest in 300"'" 500 gms. stage of brain weight and decreased gradually to the adult mean value in the 1,100-1, 199 gms stage and thereafter became stable. 3. The highest glia density was observed in the 0-1 year group but it was lower than the neuron density in the same age group and it decreased very rapidly to the minimum value in the 2-5 year group and following this it gradualy increased. In the 500-699 gIT:Is. stage of the brain weight the mean glia density was highest and decreased very rapidly to the minimun value in the 1,100-1,199 gms stage, thereafter it increased graduall; as the brain weight increased. 4. The neuron density and glia density had no sexual difference and left-right difference

Studies on Morphological Development of Male Genital Organ during Middle and Later Stages of Prenatal Period of Korean Fetus

The developmental features of the morphology of the male genital organs, such as the penis, testis, epididymis, seminal vesicle and prostate in the middle and later stages of fetal life have been investigated. 453 cases of the normal male Koran fetuses aged from 4th month to the term were used in present investigation. 1. Growth rates of the, epididymis, seminal vesicle and prostate were higher than that of the stature of the fetus. 2. Only growth rate of the testis was lower than that of the stature of the fetus, and the size of the testis was relatively large during easly stage of prenatal period 3. The male genital orans developed relatively rapidly during 10th month of gestation age. 4. The monthly averages of the measurements of the male genital organs were presented

Studies on the Cytoarchitectonics of the Parastriate Area (Brodmann's Area of 18) of the Korean Cerebral Hemisphere

This investigation is a study on the cytoarchitectonics of the wall of the cerebral sulcus in the parastriate area (Brodman's area of 18) of 179 Korean brains (103 of male, 76 of female) from the newborns to the adults. The thickness of the total cortex and of each cortical layer, the relative neuron density and the relative glia density in (1001')3 of each cortical layer and the relative total neuron and glia densities of the cortex were observed and the results were summerized as follows: 1. The mean thickness of the cortex in the 0~1 year group was 76% of the adult cortex and it increased very rapidly during 2~5 years and it was thick as the adult cortex. In the 16~20 year group it was maximum thick and thereafter it decreased gradually. The mean thickness of the adult cortex was 1. 83mm. The mean thickness of the cortex increased rapidly until the 700~800gm stage of the brain weight and increased slowly until the 1. 100~ 1. 1999m stage of the brain weight and during this stage it was thick as the adult cortex. Thereafter it had a tendency of slow increasing as the brain weight increased. 2. The relative neuron density was highest in the 0-1 year group and it decreased very rapidly in the 2-5 year group and it decreased slowly until the 11 -15 year group and at this time it is equal as the adult mean value. Thereafter it was relatively stable but it had a tendency to increase in old age. As the relation between the neuron density and the brain weight, it was hightest in 300-500gm stage of brain weight and it decreased rapidly until the brain weight was 7oo-899gm stage and it decreased slowly until the brain weight was 1. 100-1. 1999m stage and in this stage it became eaqual as the adult mean value. Thereafter it had a tendency to decrease slowly as the brain weight increased. The mean value of the neuron density of the adult cortex was 47350l. 3. The relative glia density was high in the 0-1 year group and it decreased rapidly in the 6-10 year group and was minimun valve which was lower than the adult mean value, and thereafter it increased gradually as the age increased. The mean value of the relative glia density of the adult was 606-654 which was higher than that of the adult neuron density (473-501). During the 3OO-500gm stage of the brain weight the relative glia density was high and it decreased gradually to the minimum value (542564) until the 900-1. 1999m stage of the brain weight and thereafter it increased gradually as the brain weight increased. 4. The neuron density and glia density had no sexual difference and left-right difference

Studies on the Cytoarchitectonics of the Temporal Pole Area(Brodmanns Area of 38) of the Korean Cerebral Hemisphere

This investigation is a study on the cytoarchitectonics of the wall of the cerebral sulcus in the temporal pole area of 159 Korean brains (97 brains of the male, from the newborn to the age of 85, 62 brains of the female , from the newborm to the age of 60). The thickness of the total cortex and each corticallayer, the relative neuron density and the relative glia density in C100μ)3 of each cortical layer and the relative total neuron and glia densities of the cortex were observed and the results were summerized as follows: 1. The mean thickness of the cortex in the 0~1 year group was 1. 62~ 1. 83mm, which was 72.7% of the adult cortex thickness and increased to 2. 11~2. 22 mm in the 2~5 year group which was 90% of the adult and thereafter it increased to the adult mean thickness in the 11~15 year group, and thereafter it was relatively stable. The mean thickness of the adult cortex was 2. 37mm. The thickness of the cortex increased gradually as the brain weight increased to 1. 400 gms and thereafter it was relatively stable. 2. The highest neuron density in the 0-1 year group decreased rapidly to the adult mean value in the 1115 year group and thereafter it was reatively stable. The mean neuron density of the adult cortex was 383. As the relationship between the neuron density and the brain weight, it was highest in 300-500 gms stage of brain weight and decreased rapidly in the 700-899 gms stage and decreased gradually to the adult mean value in the 1.200-1. 299 gms stage and thereafter it decreased slowly. 3. The highest glia density was observed in the 0-1 year group but it was lower than the neuron density in the same age group and it decreased very rapidly to the minimum value in the 2-5 year group and following this it gradually increased. In the 500699 gms stage of the brain weight the mean glia density was highest and deceased very rapidly to the minimum value in the 1.100-1. 199 gms stage, thereafter it increased graduay as the brain afieght increased. 4. The neuron density and glia density had no sexual difference and left •right difference

Contribution to the Studies on the Cytoarchitectonics of the Orbital Area (Brodmann's Area of 11) of Korean Cerebral Hemisphere

This investigation is a study on the cytoarchitectonics of the cerebral cortex in the gyrus top in the orbital area of 121 Korean brains(68 brains of the male from the newborn to the age of 85, 53 brair.s of the female from the newborn to the age of (1). The thickness of the total cortex ar.d ecch cortical layer, the relative neuron density ar:d the relative glia density inOOO",)3 of each cortical layer and the relative total neuron and glia densities of the cortex were observed, and the results were summerized as foils; 1. The mean thickness of the cortex in the 0-1 year group was 1. 73-1. 87111111, which was 80~82% of the adult cortex thickness and increased rapidly to 2. 12~2. 18mm in the 2~5 year group which was 95~96% of the adult cortex and then it increased slowly to the mean thickness of the adult cortex in the 11~15year group and therafter it was relatively stable but after 40 years of age it decreased slowly. The mean thickness of the adult cortex was 2. 25mm. The thickness of the cortex ir.creased rapidly as the brain weight increased to l,100~1, 1999ms and thereafter it increased very slowly as the brain weight increased. 2. The highest neuron density in the 0-1 year group decreased rapidly to the adult mean value in the 2-5 year group and thereafter it was relatively stable. The mean neuron density of the adult cortex was 506~535. The neuron density was highest in 300-499gms stage of brain weight and it decreased gradually to the adult mean valve in the 1, 100~1, 1999ms stage of the brain weight and thereafter it was relatively stable. 3. The highest glia density was observed in the O~ 1 year group but it was lower than the neuron density in the same age group and it decreased very rapidly to the minimum value in the 2~5 year group and following this it gradually increased. The mean glia density of the adult cortex was 593-615 and this was higher than the mean neuron density of the adult cortex. In the 300~499gms stage of the brain weight the mean glia density was highest and it decreased rapidly to the minimum value in the 1, 100~1, 199 gms stage and thereafter it increased gradually as the brain weight increased. 4. The neuron density and glia density had no sexual differer.ce and the left-right difference