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41.
Severe lower limb defects in exstrophy of the cloaca   总被引:1,自引:0,他引:1  
We present here a patient with exstrophy of the cloaca associated with severe lower limb defects. The limb malformations include, on the right, a split foot with distal separation of the tibia and fibula, and on the left, attachment of the lower half of the left leg with a two-toed foot at nearly a right angle to the mid left thigh. A review of the literature indicates that 17-26% of patients with cloacal exstrophy also have lower limb defects. We hypothesize that cloacal exstrophy and associated lower limb defects have a related pathogenesis and that both are related to deficiencies of caudal mesoderm or mesodermal differentiation signals. More cases of exstrophy of the cloaca with limb defects need to be reported to better characterize the limb anomalies and to more precisely determine their frequency.  相似文献   
42.
The renal toxicity of the Schardinger dextrins, alpha and beta-cyclodextrin, is manifested as a series of alterations in the vacuolar organelles of the proximal convoluted tubule. These changes begin as an increase of apical vacuoles and the appearance of giant lysosomes. The giant lysosomes characteristic of cyclodextrin nephrosis are notable because of the prominent acicular microcrystals embedded in the lysosomal matrix. Giant vacuoles devoid of acid phosphatase reaction product are found in advanced lesions. The vacuolar apparatus shows advanced changes prior to manifestation of lesions in mitochondria and other organelles. These observations indicate a role of the vacuologenic apparatus in the nephrotic process. Intracellular concentration of toxin via the lysosomal pathway represents a perversion of the physiologic function of the proximal tubule which ultimately leads to cell death.  相似文献   
43.
The presence of checkpoint mechanisms which are able to recognize damaged chromatin and thereafter to prevent exit from metaphase I has been investigated in giant mouse oocytes produced by fusion of a normal metaphase I oocyte with an equivalent oocyte with damaged chromatin. The presence of damaged chromatin did not prevent the onset of anaphase I in both sets of chromatin in the fused cells. Interestingly, fused or unfused cells containing only damaged chromatin failed to enter anaphase and persisted instead in a metaphase-like state. These results demonstrate the fragility of checkpoint controls in mammalian female germ cells.   相似文献   
44.
The distribution of specific binding of [3H]dihydroalprenolol([3H]DHA) in sucrose gradients (0.2-1.75 M), containing homogenates of the cortex of rat brain, centrifuged to equilibrium (110,000 g/16 hr), was examined in controls and after treatment with antidepressant drugs. There were no significant changes in the specific binding of [3H]DHA after acute administration of desipramine (DMI, 50 mg/kg) or clorgyline (20 mg/kg), either in terms of the number of receptors or distribution in the sucrose gradient. There was a significant decrease (29%) in the number of beta-adrenoceptors after the chronic regimen with DMI, but again no apparent alteration in the density of the receptor-containing membranes, both samples having a maximum distribution at approximately 1.1 M sucrose. Non-specific binding was maximal at 0.65 M sucrose. Electron microscopy showed that the non-specific binding was largely to myelin and the fraction containing most specific binding was composed of membrane fragments. The activity of Na+ K+ ATPase had a single broad peak (maximum at 1.1 M sucrose). Thus, at the times studied, in vivo desensitisation/internalisation of cortical beta-adrenoceptors did not apparently occur following large acute doses of antidepressant drugs and furthermore the down-regulation which followed the chronic regimen with DMI did not involve migration of receptors into "light density fractions" which are reported to be present after acute exposure to agonists in vitro.  相似文献   
45.
46.
BackgroundThe purpose of this study was to evaluate the roles of women at national trauma meetings.MethodsAvailable scientific programs for the American Association for the Surgery of Trauma (2013-19), Eastern Association for the Surgery of Trauma (2010-19), and Western Trauma Association (2010-19) as well as the Scudder Oration at the American College of Surgeons (1963–2019), were reviewed for names of participants and categorized by gender.ResultsWomen made up 963 of 2746 (35.1%) of presenters, 252 of 1020 (24.7%) of discussants, 116 of 622 (18.6%) of moderators of scientific sessions, 189 of 707 (26.7%) of panelists, and 69 of 254 (27.2%) of panel moderators. Only 12 of 126 (9.5%) of named lectures or presidential addresses were given by women.ConclusionsThe low rate of female named speakers suggests that there remains a “glass ceiling” when it comes to upper-level participation in national trauma meetings.  相似文献   
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A repeated-measures design was used to examine medical professionals' discharge planning strategies. Physicians, residents, nurses, and social workers were presented with 16 hypothetical case scenarios and asked to: (1) rate the appropriateness of four discharge options (nursing home, community nursing, adult day, and outpatient clinic care), and (2) select the most appropriate discharge plan for each case. Four within-group variables were included in the scenarios: physical impairment, caregiver availability, follow-up required, and patient compliance. Decisions were greatly influenced by caregiver availability. When a caregiver was available, respondents preferred community-based options (i.e., community nursing care or outpatient clinic); if the case involved complications (i.e., severe physical impairment, heavy follow-up, noncompliant patient), they considered community nursing care more appropriate than outpatient clinic. When a caregiver was unavailable, respondents preferred institution-based options (i.e., nursing home or adult daycare); if there were complications, they considered nursing home more appropriate than adult daycare.  相似文献   
50.
Incidental cholecystectomy during colorectal surgery.   总被引:1,自引:0,他引:1  
OBJECTIVE: To assess the risks and benefits of incidental cholecystectomy in patients having colorectal surgery. SUMMARY BACKGROUND DATA: Cholelithiasis is found commonly during abdominal surgery. Previous studies used disparate methods to assess the risks and benefits of incidental cholecystectomy and have reached contradictory conclusions. METHODS: All patients in whom asymptomatic cholelithiasis was noted during colorectal surgery between January 1982 and December 1986 were studied. Operative morbidity and long-term outcome were assessed by chart review and questionnaire. RESULTS: Three hundred five patients were identified, of whom 195 (63.9%) had an incidental cholecystectomy and 110 (36.1%) did not. The two groups were similar in terms of age, sex, primary disease, and associated medical conditions, although fewer emergency procedures, abdominoperineal resections, and Hartmann's procedures were needed in the cholecystectomy group. The overall operative morbidity rate was the same in both groups. The long-term risk for developing small bowel obstruction was also similar. After a median follow-up of 6 years after hospital discharge, biliary pain or cholecystitis developed in 16 patients (14.6%) in the "no cholecystectomy" group, 12 of whom have had cholecystectomy. Two additional patients had cholecystectomy for acute postoperative cholecystitis while still in the hospital. Six more patients have had incidental cholecystectomy at subsequent laparotomies. The cumulative probability of needing cholecystectomy at 2 and 5 years after the initial colorectal operation was 12.1% and 21.6%, respectively. CONCLUSIONS: Incidental cholecystectomy was not associated with increased postoperative morbidity, whereas the long-term risk that previously asymptomatic gallstones would become symptomatic was substantial. Unless there are clear contraindications, patients with asymptomatic gallstones who have colorectal surgery should have concomitant cholecystectomy.  相似文献   
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