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排序方式: 共有388条查询结果,搜索用时 31 毫秒
81.
82.
LD Ormerod JA Larkin CA Margo PR Pavan MM Menosky DO Haight JP Nadler BG Yangco SM Friedman R Schwartz JT Sinnott 《Canadian Metallurgical Quarterly》1998,26(1):34-45; discussion 46-7
Eleven patients with rapidly progressive herpetic retinal necrosis (RPHRN) complicating AIDS were investigated retrospectively to study the disease spectrum, systemic involvement, and therapy. The mean CD4 cell count was 24/microL. There was a characteristic disease pattern with rapid progression, 82% bilaterality, relative resistance to intravenous antiviral therapy, and 70% retinal detachment. Varicella-zoster virus was the probable cause in 10 patients (detected by polymerase chain reaction in two eyes investigated), and herpes simplex virus was the probable cause in one. Cutaneous zoster occurred previously in 73% but was not concurrent. Seventy-three percent had central nervous system disease, possibly virus-related. RPHRN may be a local herpetic recrudescence in an immune-privileged site with transneural spread. Only four of 20 affected eyes retained useful vision. Poor ocular bioavailability, retinal ischemia, acquired drug resistance, and strain pathogenicity may underlie treatment failure. Acyclovir therapy appears relatively ineffective. Combined intravenous and intravitreal therapy with foscarnet and ganciclovir may be the best current management. Research advances are needed urgently. 相似文献
83.
AA Khan SW Shah A Alam AK Butt F Shafqat DO Castell 《Canadian Metallurgical Quarterly》1998,93(7):1064-1067
OBJECTIVE: Duration of Inflation in pneumatic balloon dilatation as treatment of achalasia has been variable ranging from 15 s to 6 min. A 60 s duration appears to be most often used. We compared the efficacy of dilation of achalasia with either 6- or 60-s inflation duration using a Rigiflex dilator of 3.0 cm diameter. METHODS: Eighty-one consecutive patients were prospectively studied in a randomized fashion, 41 in the 60-s group (A) and 40 patients in the 6-s group (B). Mean age of group A was 43 +/- 16.2 yr and of group B was 40 +/- 16.4 yr. Symptoms of dysphagia, chest pain, heartburn, regurgitation, and night cough were evaluated at basal (before dilation), 1- and 6-month intervals after dilation in both groups. Barium swallow was done to assess esophageal emptying 1 wk before dilation and 5 min postdilation in both groups. RESULTS: Significant and sustained improvement was seen for all symptoms in both groups. In addition, the degree of improvement in symptom scores between the two groups was similar. Barium esophagram in both groups at basal and immediately postdilation showed significant improvement in barium emptying but there was no significant difference between the two groups, indicative of equal efficacy in both distention times. Two patients needed repeat dilatation in group A and one in group B, with one drop out from group A, who was lost to follow-up, and was excluded from the analysis. No perforation occurred. CONCLUSION: Short duration of pneumatic balloon dilatation (6-s) is as effective as longer duration (60-s) in treatment of achalasia. 相似文献
84.
The anti-emetic efficiency of orally administered ondansetron and granisetron has been tested in macaques exposed to a mixed y and neutron radiation (6 Gy) with a high neutron/gamma-ray ratio. Our experiments reveal that a single delivery of ondansetron (1 or 2 mg kg(-1)) or of granisetron (0.25 mg kg(-1)) 45-90 min before irradiation or 35-45 min after irradiation was not totally effective. Conversely, the delivery of two doses with the same delay prior to and after exposure led to a complete prevention of vomiting and retching. These observations can be explained by the dual mechanism of radiation-induced emesis: an early peripheral mechanism and a later central mechanism. Two deliveries of 5-HT3 receptor antagonists seem to disrupt serotonergic transmission at the brain stem structures and to affect the peripheral release of serotonin from the gut, thus completely preventing radiation-induced vomiting. This study confirms that the 5-HT3-dependent mechanisms that mediate emesis are similar for both neutron and gamma radiation. 相似文献
85.
JA César G Gomes BL Horta AK de Oliveira AK Saraiva DO Pardo LM Silva CL Rodghiero MR Gross 《Canadian Metallurgical Quarterly》1997,31(6):566-571
To study pancreas enzyme content regulation when the diet was modified in suckling goats, a comparison was made between kids fed a milk replacer and ones fed maternal milk. A total of 25 preruminant Granadina breed goats were bottle-fed a milk replacer ad libitum from postnatal days 3 to 28 (until the age of 3 days kids had been fed colostrum). Body weight, pancreas weight, total protein concentration, and enzyme activities in pancreatic tissue were determined at 3, 7, 14, 21 and 28 days of age, and the results were compared to those previously obtained in kids fed maternal milk for the same period. Lipase activity was significantly lower in the group fed milk replacer, which was poorer in fat. Amylase activity was higher in this group, perhaps due to the starch products present in the milk substitute. However, the postnatal evolution of chymotrypsin activity followed a similar pattern regardless of diet. Our results seem to confirm that in preruminant kids there is a nutritional regulation of pancreatic amylase and lipase activities, depending on the amounts of their respective substrates in the diet, similar to that described in nonruminants. 相似文献
86.
The expression and organization patterns of several myofibrillar proteins were analysed in the putative myofibroblast cell line BHK-21/C13. Although this cell line originates from renal tissue, the majority of the cells express titin. In these cells, titin is, under standard culture conditions, detected in myofibril-like structures (MLSs), where it alternates with non-muscle myosin (NMM). Expression of sarcomeric myosin heavy chain (sMyHC) is observed in a small minority of cells, while other sarcomeric proteins, such as nebulin, myosin binding protein C (MyBP-C), myomesin and M-protein are not expressed at all. By changing the culture conditions in a way equal to conditions that induce differentiation of skeletal muscle cells, a process reminiscent of sarcomerogenesis in vitro is induced. Within one day after the switch to a low-nutrition medium, myofibrillar proteins can be detected in a subset of cells, and after two to five days, all myofibrillar proteins examined are organized in typical sarcomeric patterns. Frequently, cross-striations are visible with phase contrast optics. Transfection of these cells with truncated myomesin fragments showed that a specific part of the myomesin molecule, known to contain a titin-binding site, binds to MLSs, whereas other parts do not. These results demonstrate that this cell line could serve as a powerful model to study the assembly of myofibrils. At the same time, its transfectability offers an invaluable tool for in vivo studies concerning binding properties of sarcomeric proteins. 相似文献
87.
88.
GC López Villalta V Furió-Bacete E Ortiz Oshiro DO López D Vaca Vaticón JA Fdez-Represa 《Canadian Metallurgical Quarterly》1995,80(3):223-226
The effect of maternal hyperglycemia on fetal regional circulation in appropriate for gestational age and small for gestational age fetuses was evaluated. Color Doppler flow imaging and pulsed Doppler ultrasonographic assessments were made on 15 appropriate for gestational age and 19 small for gestational age fetuses, ranging from 33 to 40 weeks' gestation before, 60 minutes, and 120 minutes after a maternal 75 g glucose load. The pulsatility index (PI) was calculated for middle cerebral artery, descending aorta, splenic artery, renal artery, femoral artery, and umbilical artery. Simultaneously, maternal plasma glucose concentration was measured. Baseline PI value (1.50 +/- 0.31) for middle cerebral artery in small for gestational age fetuses was significantly lower than that (1.89 +/- 0.37) in appropriate for gestational age fetuses (p < 0.05); however, there were no significant differences in baseline PI values for other arteries in both groups. In appropriate for gestational age fetuses, the mean PI decreased from 1.89 +/- 0.37 to 1.47 +/- 0.33 at 60 minutes, and to 1.55 +/- 0.32 at 120 minutes (p < 0.05), but no changes were found in the other arteries. In small for gestational age fetuses, there was no significant change in PI value for each artery before and after maternal glucose load. Maternal hyperglycemia induces a significant decrease in cerebrovascular resistance in appropriate for gestational age fetuses but not in small for gestational age fetuses. These results provide a foundation for evaluating the effect of maternal hyperglycemia on fetal regional circulation. 相似文献
89.
90.