1,211 research outputs found
Development of eye colors in Drosophila: some properties of the hormones concerned
The substance inducing the production of pigment in the eyes of vermilion brown mutants of Drosophila melanogaster has been shown to be a relatively stable chemical entity possessing true hormone-like activity.
A simple method for obtaining hormone solutions has been developed involving extraction of dried wild type Drosophila pupae with ethyl alcohol and water.
A logarithmic proportionality has been found to exist between the amount of hormone and the induced eye color. This relationship provides a simple method for the quantitative determination of hormone concentration in given extracts.
Larvae and pupae of D. melanogaster contain an intracellular enzyme which inactivates the hormone in the presence of molecular oxygen. The hormone is not oxidized under ordinary conditions with either molecular oxygen or hydrogen peroxide.
The hormone has been found to be an amphoteric compound with both acidic and basic groups and with a molecular weight between 400 and 600.
The solubility and precipitation reactions of the hormone suggest its amino acid-like nature. However, the instability to heat, acid, and alkali, and its rather restricted occurrence indicate a rather complex specific structure
Measuring the eccentricity of the Earth orbit with a nail and a piece of plywood
I describe how to obtain a rather good experimental determination of the
eccentricity of the Earth orbit, as well as the obliquity of the Earth rotation
axis, by measuring, over the course of a year, the elevation of the Sun as a
function of time during a day. With a very simple "instrument" consisting of an
elementary sundial, first-year students can carry out an appealing measurement
programme, learn important concepts in experimental physics, see concrete
applications of kinematics and changes of reference frames, and benefit from a
hands-on introduction to astronomy.Comment: 12 pages, 6 figure
Hepatic Arterial Therapy with Drug-Eluting Beads in the Management of Metastatic Bronchogenic Carcinoma to the Liver: A Multi-Institutional Registry
Introduction. There has been limited information reported on the use of hepatic arterial therapy in liver dominant hepatic metastases arising from lung cancer. The aim of this study was to evaluate the safety and efficacy of hepatic arterial therapy in the treatment of liver dominant hepatic metastases arising from lung cancer. Methods. Thirteen patients underwent a total of 30 treatment sessions with Drug-Eluting Beads. Eight of the thirteen received only doxorubicin DEB (17 of the total treatments), and four patients received Irinotecan DEB (7 of the total treatments). Results. The planned preprocedural dosage was a median of 75 mg (range 19–200), with total hepatic dose exposure being a median of 150 mg (range 0–458), with a technical success rate of 97% in all 29 treatments. There were 4 adverse events related to treatment, but no evidence of hepatic insufficiency. Overall 6-month and 12-month response rates were 50%. After a median followup of 24 months, the median overall survival in this cohort was 14 months (range 7–48 months). Conclusion. Drug-eluting beads loaded with doxorubicin (DEBDOX) or irinotecan (DEBIRI) can be safely and effectively used in treatment of patients with liver predominant metastatic disease from lung cancer
Transarterial Chemoembolization of Metastatic Colorectal Carcinoma with Drug-Eluting Beads, Irinotecan (DEBIRI): Multi-Institutional Registry
The purpose of this study was to evaluate the patient tolerance and efficacy of delivering locoregional chemotherapy to metastatic colorectal (MC) hepatic metastases via hepatic trans-arterial approach using irinotecan loaded drug eluting beads. This open-label, multi-center, single arm study included 30 MC patients, who had failed first line therapy. Of the 57 total embolization sessions, 12 (21% of sessions) were associated with adverse reactions during or after the treatment. After a median followup of 9 months, response rates by modified RECIST were 75% at 3 months and 66% at 6 months. Hepatic trans-arterial therapy using Irinotecan loaded DC BeadTM
was safe and effective in the treatment of MCC as demonstrated by a minimal complication rate and acceptable tumor response
Microscope and microâ camera assessment of Schneiderian membrane perforation via transcrestal sinus floor elevation: A randomized ex vivo study
ObjectiveWe sought to assess the effectiveness of using a microscope and nonâ invasive camera for assessing sinus membrane perforations during transcrestal sinus floor elevation (TSFE).Materials and methodsFive fresh human cadaver heads corresponding to eight maxillary sinuses (six bilateral and two unilateral) underwent 4 TSFEs per sinus (a total of 32 single site elevations). Each elevation was randomly assigned to receive a three or six mm membrane elevation height (MEH). A microscope and microâ camera were used to assess the sinus membrane perforation. Afterwards, radiological and clinical membrane perforation assessments were performed. The statistical analysis results are expressed using the means, standard deviations, range values of the residual ridge height (RRH), residual ridge width (RRW), sinus membrane thickness (SMT) and incidence of perforation (IoP). Generalized linear methods were used to test for the correlation of RRH and MEH to the microscope and microâ camera perforation assessments and the correlation of microscope and microâ camera assessments with the postâ operative CBCT and crestal liquid evaluation.ResultsThe cumulative percentage of IoP was 40.62%, (23.07% with 3 mm MEH, and 76.92% with 6 mm MEH, p < 0.05). The perforation assessed using either the microscope or microâ camera coincided with the postâ operative CBCT and crestal liquid assessment in 87.55% sites. No significant correlation was found between the microscope or microâ camera assessments with RRH or MEH.ConclusionApplication of a microscope and microâ camera during transcrestal sinus floor elevation may allow the detection of the integrity of the Schneiderian membrane with greater than 85% accuracy in this ex vivo model.Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/149727/1/clr13453.pdfhttps://deepblue.lib.umich.edu/bitstream/2027.42/149727/2/clr13453_am.pd
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