718,411 research outputs found
Book Review
Review of: ROBERT H. BLANK, MOTHER AND FETUS: CHANGING NOTIONS OF MATERNAL RESPONSIBILITY. (Greenwood Press 1992) [207 pp.], Appendix, bibliography, figures, index, preface, tables. LC-91- 38029; ISBN 0-313-27639-0. [$45.00 cloth. 88 Post Road West, Box 5007, Westport CT 06881.
Review of: Thomas Szasz, Fatal Freedom: The Ethics and Politics of Suicide
A review of the book Fatal Freedom: The Ethics and Politics of Suicide by Thomas Szasz (Praeger Publishers 1999). Preface, acknowledgments, appendix, notes, selected bibliography, indexes. ISBN 0-275-96646-1 [178 pp. $25.95. Hardbound, 88 Post Road West, Westport, CT 06881]
Perforated Meckel\u27s diverticulitis presenting as a mesenteric abscess: case report
Only 2% of patients with Meckel’s diverticulae (MD) will manifest clinical problems. Diverticulitis occurs in approximately 10-20% of patients with symptomatic MD and more often in the elderly population. We report a case of Meckels diverticulitis presenting with perforation and mesenteric abscess in a young African man. The authors present information on diagnostic pitfalls and advise a lower threshold for consideration of MD as a differential diagnosis of acute right iliac fossa pain especially when the CT scan denotes a normal appendix in a male patient
NASA/ESA CT-990 Spacelab simulation. Appendix A: The experiment operator
A joint NASA/ESA endeavor was established to conduct an extensive spacelab simulation using the NASA CV-990 airborne laboratory. The scientific payload was selected to perform studies in upper atmospheric physics and infrared astronomy with principal investigators from France, the Netherlands, England, and several groups from the United States. Two experiment operators from Europe and two from the U.S. were selected to live aboard the aircraft along with a mission manager for a six-day period and operate the experiments in behalf of the principal scientists. This appendix discusses the experiment operators and their relationship to the joint mission under the following general headings: selection criteria, training programs, and performance. The performance of the proxy operators was assessed in terms of adequacy of training, amount of scientific data obtained, quality of data obtained, and reactions to problems that arose in experiment operation
Mucocele of the appendix: An unusual cause of lower abdominal pain in a patient with ulcerative colitis
The authors report the case of a 60-year-old male patient. In November 2001 he developed intestinal symptoms of bloody diarrhea and abdominal pain. Colononoscopy and biopsy established the diagnosis of ulcerative colitis (proctosigmoiditis). The disease activity was moderate at the beginning. No significant laboratory alterations were found (including CEA, CA19-9), and mesalazine was started orally. He was in remission until November 2003, when he was admitted to our Outpatient Clinic for upper and right lower abdominal pain and bloody diarrhea. Colonoscopy found proctosigmoiditis with a moderate activity, gastroscopy revealed chronic gastritis, laboratory data was normal. Treatment was amended with mesalazine clysma and methylprednisolone (16 mg) orally. Symptoms ameliorated; however, right lower abdominal pain persisted. US and CT examination demonstrated a pericecal cystic mass (11 cm x 3.5 cm). At first pericecal abscess was suspected, as the previous US examination (6 mo earlier) had revealed normal findings. Fine needle aspiration was performed. Cytology confirmed the diagnosis of mucocele. The patient underwent partial cecum resection and extirpation of the mucocele. He recovered well and the final histology revealed a cystadenoma of the appendix. Follow up was started. The patient is now free of symptoms. Although primary adenocarcinoma of the appendix is uncommon, the authors emphasize that preoperative diagnosis of an underlying malignancy in a mucocele is important for patient management; however, it is difficult on imaging studies
Unusual abscesses associated with colon cancer: report of three cases
Three cases of colon cancer accompanied by unusual abscess formation are reported. Case I : A 77-year-old man was diagnosed with a paracolic abscess formation behind the cecum and a swollen appendix by computed tomography (CT) scan. Case II : An 85-year-old woman was diagnosed with an abscess formation of the right iliopsoas muscle, a swollen appendix, and a thickened right colon wall by CT scan. After antibiotic therapy failed, both patients underwent ileocecal resection urgently under suspicion of appendicitis, but cecal cancer around the entrance to the appendix caused secondary appendicitis in both cases. Case III : A 50-year-old woman was diagnosed with sigmoid colon cancer with an abscess formation in the pelvic cavity concomitant with ovarian tumor. A Hartmann procedure was performed, and a pathological examination revealed that a subserosal abscess behind the sigmoid colon cancer perforated the rectum with abscess formation. All cases were definitively diagnosed intraoperatively. The cancer recurred in cases I and III. We emphasize that precise surgical evaluation has an important role in the diagnosis of these complicated diseases. In addition, surgery affords the patient the best chance of recovery, and in these advanced cases radical treatment is recommended as early as possible
Computed Tomography With Intravenous Contrast Alone: The Role of Intra‐abdominal Fat on the Ability to Visualize the Normal Appendix in Children
Background Computed tomography ( CT ) with enteric contrast is frequently used to evaluate children with suspected appendicitis. The use of CT with intravenous ( IV ) contrast alone ( CT IV ) may be sufficient, however, particularly in patients with adequate intra‐abdominal fat ( IAF ). Objectives The authors aimed 1) to determine the ability of radiologists to visualize the normal (nondiseased) appendix with CT IV in children and to assess whether IAF adequacy affects this ability and 2) to assess the association between IAF adequacy and patient characteristics. Methods This was a retrospective 16‐center study using a preexisting database of abdominal CT scans. Children 3 to 18 years who had CT IV scan and measured weights and for whom appendectomy history was known from medical record review were included. The sample was chosen based on age to yield a sample with and without adequate IAF . Radiologists at each center reread their site's CT IV scans to assess appendix visualization and IAF adequacy. IAF was categorized as “adequate” if there was any amount of fat completely surrounding the cecum and “inadequate” if otherwise. Results A total of 280 patients were included, with mean age of 10.6 years (range = 3.1 to 17.9 years). All 280 had no history of prior appendectomy; therefore, each patient had a presumed normal appendix. A total of 102 patients (36.4%) had adequate IAF . The proportion of normal appendices visualized with CT IV was 72.9% (95% confidence interval [ CI ] = 67.2% to 78.0%); the proportions were 89% (95% CI = 81.5% to 94.5%) and 63% (95% CI = 56.0% to 70.6%) in those with and without adequate IAF (95% CI for difference of proportions = 16% to 36%). Greater weight and older age were strongly associated with IAF adequacy (p < 0.001), with weight appearing to be a stronger predictor, particularly in females. Although statistically associated, there was noted overlap in the weights and ages of those with and without adequate IAF . Conclusions Protocols using CT with IV contrast alone to visualize the appendix can reasonably include weight, age, or both as considerations for determining when this approach is appropriate. However, although IAF will more frequently be adequate in older, heavier patients, highly accurate prediction of IAF adequacy appears challenging solely based on age and weight. Resumen Tomografía Computarizada Únicamente con Contraste Intravenoso: El Papel de la Grasa Intrabadominal en la Capacidad para Visualizar el Apéndice Normal en los Niños Introduction La tomografía computarizada ( TC ) con contraste entérico es usada frecuentemente para evaluar a los niños con sospecha de apendicitis. El uso de la TC únicamente con contraste intravenoso ( TC IV ) puede ser suficiente, especialmente en pacientes con adecuada grasa intrabdominal ( GIA ). Objetivos 1) Determinar la capacidad de los radiólogos para visualizar el apéndice normal (sin enfermedad) con TC IV en niños, y valorar si la cantidad de GIA afecta a esta capacidad; y 2) valorar la asociación entre la idoneidad de la GIA y las características del paciente. Metodología Estudio retrospectivo de 16 hospitales que utilizó una base de datos prexistente de TC abdominales. Se incluyó a los niños entre 3 y 18 años que tenían una TC IV , una medida del peso e historia de apendectomía conocida por la revisión de la historia clínica. La muestra se eligió en base a la edad con el fin de conseguir una muestra con y sin GIA adecuada. Los radiólogos de cada centro releyeron las TC IV de sus centros para valorar la visualización del apéndice y la adecuación de la GIA . La GIA se clasificó como “adecuada” si había cualquier cantidad de grasa completamente alrededor del ciego e “inadecuada” si era de otra manera. Resultados Se incluyeron 280 pacientes, con una media de edad de 10,6 años (rango 3,1 a 17,9 años). Ninguno tenía historia previa de apendectomía; por lo tanto todos los pacientes tuvieron un apéndice presumiblemente normal. Ciento dos pacientes (36,4%) tuvieron GIA adecuada. El porcentaje de apéndices normales visualizados con TC IV fue de 72,9% ( IC 95% = 67,2% a 78,0%); la proporción fue 89% ( IC 95% = 81,5% a 94,5%), y 63% ( IC 95% = 56,0% a 70,6%) en aquéllos con y sin GIA adecuada ( IC 95% para la diferencia de proporciones = 16% a 36%). El mayor peso y la mayor edad se asociaron fuertemente con la adecuación de la GIA (p < 0,001), y el peso resultó ser el mayor factor predictivo, especialmente en mujeres. Aunque se asoció estadísticamente, se vio un solapamiento en los pesos y edades de aquéllos con y sin GIA adecuada. Conclusiones Los protocolos que usan la TC IV para visualizar el apéndice pueden razonablemente incluir el peso, la edad, o ambas como consideraciones para determinar cuándo esta aproximación es apropiada. Sin embargo, aunque la cantidad de GIA será frecuentemente más apropiada en los pacientes más mayores y de mayor peso, la predicción certera de adecuación de GIA es altamente desafiante si se basa sólo en la edad y el peso.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/99695/1/acem12185.pd
Large, long range tensile forces drive convergence during
Indirect evidence suggests that blastopore closure during gastrulation of anamniotes, including amphibians such as Xenopus laevis, depends on circumblastoporal convergence forces generated by the marginal zone (MZ), but direct evidence is lacking. We show that explanted MZs generate tensile convergence forces up to 1.5 mN during gastrulation and over 4 mN thereafter. These forces are generated by convergent thickening (CT) until the midgastrula and increasingly by convergent extension (CE) thereafter. Explants from ventralized embryos, which lack tissues expressing CE but close their blastopores, produce up to 2 mN of tensile force, showing that CT alone generates forces sufficient to close the blastopore. Uniaxial tensile stress relaxation assays show stiffening of mesodermal and ectodermal tissues around the onset of neurulation, potentially enhancing long-range transmission of convergence forces. These results illuminate the mechanobiology of early vertebrate morphogenic mechanisms, aid interpretation of phenotypes, and give insight into the evolution of blastopore closure mechanisms. © Shook et al
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