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51.
C Liu AB Bahnson JT Dunigan SC Watkins JA Barranger 《Canadian Metallurgical Quarterly》1998,76(11):773-781
The majority of studies dealing with DNA analyses are made on fixed cells. In this context, the efficiency as fixatives of ethanol, methanol, acetone, Carnoy, Boehm-Sprenger and aldehydes was determined using two different DNA fluorescent probes, Hoechst 33342 and propidium iodide. The purpose of our study was to find the fixative that would provide the best results with respect to the following parameters: aggregates, cell size and granularity, and DNA staining analysis. Using murine fibroblasts, we found that 68% ethanol, 85% methanol and aldehydes did not increase aggregate formation, whereas Carnoy, acetone or Boehm-Sprenger fixatives did. The results show that aldehydes seem to alter cell size least. All fixatives induce an increase in cell granularity, which is very pronounced with alcohols, but aldehydes alter morphology less than alcohols. We observed that the fixatives giving the best resolution with Hoechst 33342 staining lead to a lower measurement variability than with propidium iodide staining. This study leads us to conclude that 68% ethanol and 85% methanol can be considered as appropriate fixatives for flow cytometry studies of DNA content. 相似文献
52.
BACKGROUND: Auxiliary liver transplantation has several advantages over standard orthotopic liver transplantation. However, functional competition has been reported even in auxiliary partial orthotopic liver transplantation (APOLT). We evaluated herein the interaction in APOLT between the native liver and the graft in terms of portal blood flow and regeneration. The need for diversion of the portal blood flow to the graft was also assessed. METHODS: A total of 15 patients received APOLT from living donors. Portal blood flow to the native liver was preserved in 6 patients, and the portal vein to the native liver was preemptively transected at the time of transplantation in 9 patients. RESULTS: Of the patients with preservation of the portal blood flow to the native liver, two showed inadequate graft portal blood flow just after operation, and in the other three patients the graft portal blood flow decreased or the graft atrophied after deterioration of the graft function. In the patients with preemptive transection of the portal vein to the native liver, optimal graft portal blood flow was obtained, and the native liver, supplied only by arterial inflow, supported a small-for-size graft until the graft regenerated. The damage to the native liver was minimal. CONCLUSIONS: Functional competition may occur in APOLT with preservation of the portal blood flow to the native liver, whereas preemptive transection of the native liver portal vein is a safe procedure and effectively prevents the portal steal phenomenon. 相似文献
53.
OBJECTIVES: Little information is available about the intake of very-long-chain n-3 fatty acids in random samples of populations. We examined if the intake of these fatty acids was associated with gender, social status and lifestyle in a similar way as other indicators for a healthy diet in a nationwide survey. DESIGN AND SUBJECTS: Data were obtained from self-administered quantitative food frequency questionnaires filled in by a representative sample of Norwegian men and women, aged 16-79 y. 3144 (63%) of the invited subjects responded with acceptable questionnaires. RESULTS: Daily intake of very-long-chain n-3 fatty acids was on average 0.9 g/d and 0.4% of total energy was derived from these fatty acids. Energy derived from very-long-chain n-3 fatty acids was slightly higher among men than women, and two-fold higher among subjects aged 60-79 vs 16-29 y. White collar workers had higher intake of very-long-chain n-3 fatty acids than blue collar workers. Men and women in the highest quartile of intake of very-long-chain n-3 fatty acids had 2-3 E% higher fat intake (mostly mono- and polyunsaturated fatty acids), as compared to individuals in the lowest quartile. They also had 3-4 fold higher daily intake of retinol and vitamin D, as well as 20-50% higher intake of fruits and vegetables, dietary fibre and vitamin C. CONCLUSIONS: Intake of very-long-chain n-3 fatty acids was correlated to indicators for healthy dietary habits. However, contrary to many other indicators of a healthy diet, energy derived from very-long-chain n-3 fatty acids was not significantly associated with female gender or non-smoking. 相似文献
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Although thoracoscopic sympathectomy or sympathicotomy is the best treatment for hyperhidrosis palmaris, a new approach of clipping only without transection of T2-sympathetic trunk is just as effective. Aside from the guaranteed cure of hyperhidrosis, this new method has fewer complications and has the advantage of recovery of the sympathetic tone in the hands if the procedure is reversed by the removal of the clips. Between March 18 and September 30 of 1996, 326 patients (190 female and 136 male with a mean age of 20.5 years) underwent thoracoscopic T2-sympathetic block by clipping to treat hyperhidrosis. Good results and few complications were noted during follow up six months to one year postoperatively. Five of the 326 patients, all female, had the operation reversed because of intolerable compensatory sweating. Three recovered from the compensatory sweating within two months and had less palmar sweating than before their sympathetic block; the fourth achieved relief of compensatory sweating after nine months, and the fifth reported no improvement. 相似文献
57.
A neostriatal habit learning system in humans 总被引:1,自引:0,他引:1
Amnesic patients and nondemented patients with Parkinson's disease were given a probabilistic classification task in which they learned which of two outcomes would occur on each trial, given the particular combination of cues that appeared. Amnesic patients exhibited normal learning of the task but had severely impaired declarative memory for the training episode. In contrast, patients with Parkinson's disease failed to learn the probabilistic classification task, despite having intact memory for the training episode. This double dissociation shows that the limbic-diencephalic regions damaged in amnesia and the neostriatum damaged in Parkinson's disease support separate and parallel learning systems. In humans, the neostriatum (caudate nucleus and putamen) is essential for the gradual, incremental learning of associations that is characteristic of habit learning. The neostriatum is important not just for motor behavior and motor learning but also for acquiring nonmotor dispositions and tendencies that depend on new associations. 相似文献
58.
AC Lidral PA Romitti AM Basart T Doetschman NJ Leysens S Daack-Hirsch EV Semina LR Johnson J Machida A Burds TJ Parnell JL Rubenstein JC Murray 《Canadian Metallurgical Quarterly》1998,63(2):557-568
Nonsyndromic cleft lip with or without cleft palate (CL/P) and nonsyndromic cleft palate only (CPO) are common congenital anomalies with significant medical, psychological, social, and economic ramifications. Both CL/P and CPO are examples of complex genetic traits. There exists sufficient evidence to hypothesize that disease loci for CL/P and CPO can be identified by a candidate-gene linkage-disequilibrium (LD) strategy. Candidate genes for clefting, including TGFA, BCL3, DLX2, MSX1, and TGFB3, were screened for LD with either CL/P or CPO in a predominantly Caucasian population, with both case-control- and nuclear-family-based approaches. Previously reported LD for TGFA with both CL/P and CPO could not be confirmed, except in CL/P patients with a positive family history. Also, in contrast to previous studies, no LD was found between BCL3 and either CL/P or CPO. Significant LD was found between CL/P and both MSX1 and TGFB3 and between CPO and MSX1, suggesting that these genes are involved in the pathogenesis of clefting. In addition, a mutation search in the genes DLX2, MSX1, and TGFB3 was performed in 69 CPO patients and in a subset of the CL/P patients. No common mutations were found in the coding regions of these genes; however, several rare variants of MSX1 and TGFB3 were found that may alter the latters' normal function. These results form the basis for future research, including (a) mutation searches in the MSX1 and TGFB3 genes in Caucasian CL/P patients and (b) extension of the search for MSX1 mutations in CPO patients to the noncoding regions. 相似文献
59.
OBJECTIVE: To determine outcome for foals with incomplete ossification of the tarsal bones and to determine whether clinical and radiographic abnormalities at the time of initial examination were associated with outcome. DESIGN: Retrospective study. ANIMALS: 22 foals. PROCEDURE: Information on signalment, history, owner's initial complaint, clinical findings, whether tarsus valgus was evident, and radiographic abnormalities was obtained from medical records. Radiographic lesions were classified as type I (i.e., incomplete ossification with < 30% collapse of the affected bones) or type II (incomplete ossification with > 30% collapse and pinching or fragmentation of the affected bones). Follow-up information was obtained via telephone conversations with owners. RESULTS: Foals were between 1 day and 10 months old when first examined. Eleven were premature (i.e., < 320 days of gestation) or were twins. Sixteen had tarsus valgus. Severity of radiographic lesions was associated with outcome; 4 of 6 foals with type-I incomplete ossification of the tarsal bones performed as intended, but only 3 of 16 foals with type-II incomplete ossification of the tarsal bones performed as intended. CLINICAL IMPLICATIONS: For foals with incomplete ossification of the tarsal bones, severity of the radiographic lesions was associated with outcome. Foals with type-II incomplete ossification of the tarsal bones have a guarded prognosis for athletic soundness. 相似文献
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