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991.
A case of fixed drug eruption due to rifampin in a leprosy patient is described. Fixed drug eruption due to rifampin with the classical residual hyperpigmentation has not been described before.  相似文献   
992.
993.
OBJECTIVE: To surgically create complete portacaval shunts in dogs during temporary arrest of intestinal arterial and portal venous blood flow. DESIGN: Complete portacaval anastomoses were surgically created, and liver function was evaluated for 14 to 18 weeks after surgery. ANIMALS: 32 adult mixed-breed dogs of either sex. PROCEDURE: Administration of deferoxamine and temporary intestinal arterial occlusion were used to minimize the intestinal cellular damage resulting from the complete, temporary arrest of portal venous blood flow during creation of the portacaval anastomosis. Side-to-side, appositional anastomoses ( > 2 cm diameter) were formed between the portal vein and caudal vena cava. Dogs were observed daily for signs of hepatic encephalopathy, and food intake was recorded. Body weight was recorded weekly. Preprandial plasma ammonia, serum urea nitrogen, and glucose concentrations and sulfobromophthalein retention were measured monthly. The dogs were euthanatized, and necropsy was performed 14 to 18 weeks after surgery. RESULTS: 30 of 32 dogs recovered without complications. Complete portosystemic shunting was documented by increased plasma ammonia concentration, decreased serum urea nitrogen and glucose concentrations, prolonged sulfobromophthalein retention (P < 0.01), and inspection at necropsy. CONCLUSION: This method of providing temporary, complete arrest of portal venous blood flow was helpful in allowing accurate, appositional portacaval anastomoses to be created that remained patent for 14 to 18 weeks. CLINICAL RELEVANCE: This method of providing temporary, complete arrest of portal venous blood flow may prove useful in clinical surgery when temporary arrest of portal blood flow is desired.  相似文献   
994.
2,5,6-Trichloro-1-beta-D-ribofuranosyl benzimidazole (TCRB) is a potent and selective inhibitor of human cytomegalovirus (HCMV) replication. TCRB acts via a novel mechanism involving inhibition of viral DNA processing and packaging. Resistance to the 2-bromo analog (BDCRB) has been mapped to the UL89 open reading frame (ORF), and this gene product was proposed as the viral target of the benzimidazole nucleosides. In this study, we report the independent isolation of virus that is 20- to 30-fold resistant to TCRB (isolate C4) and the characterization of the virus. The six ORFs known to be essential for viral DNA cleavage and packaging (UL51, UL52, UL56, UL77, UL89, and UL104) were sequenced from wild-type HCMV, strain Towne, and from isolate C4. Mutations were identified in UL89 (D344E) and in UL56 (Q204R). The mutation in UL89 was identical to that previously reported for virus resistant to BDCRB, but the mutation in UL56 is novel. Marker transfer analysis demonstrated that each of these mutations individually caused approximately 10-fold resistance to the benzimidazoles and that the combination of both mutations caused approximately 30-fold resistance. The rate and extent of replication of the mutants was the same as for wild-type virus, but the viruses were less sensitive to inhibition of DNA cleavage by TCRB. Mapping of resistance to UL56 supports and extends recent work showing that UL56 codes for a packaging motif binding protein which also has specific nuclease activity (E. Bogner et al., J. Virol. 72:2259-2264, 1998). Resistance which maps to two different genes suggests that their putative proteins interact and/or that either or both have a benzimidazole ribonucleoside binding site. The results also suggest that the gene products of UL89 and UL56 may be antiviral drug targets.  相似文献   
995.
BACKGROUND: Atherosclerotic lesions of the carotid and lower extremity arteries may be associated with renal artery stenosis and influence the management of patients with renal artery disease. OBJECTIVE: To document the prevalence and clinical features of carotid and lower extremity arterial disease in patients with renal artery atherosclerosis. METHODS: An analysis of baseline data on 149 patients enrolled in a prospective natural history study of atherosclerotic renal artery stenosis. Patients with at least 1 abnormal renal artery by duplex scanning were eligible. Carotid artery disease was evaluated by duplex scanning, and ankle/brachial indices were used to assess the lower extremity arteries. Disease at each of the 3 arterial sites was classified as mild, moderate, or severe based on the extent of involvement on both sides. Serum urea nitrogen, creatinine, and lipid levels were also measured. RESULTS: Severe renal, carotid, or lower extremity arterial disease was present in 44%, 19%, and 21% of the patients, respectively. There was a trend for patients with increasing degrees of renal artery disease to have increasing degrees of carotid and lower extremity arterial disease. The prevalence of severe carotid artery disease increased from 7% in the mild renal artery group to 28% in the severe renal artery group. Clinical factors that were most predictive of severe disease were elevated apolipoprotein B levels for the renal arteries, high serum urea nitrogen or creatinine levels for the carotid arteries, and smoking for the lower extremity arteries. CONCLUSIONS: There was a strong association between severe renal artery atherosclerosis and severe carotid artery disease. Patients with renal artery disease also had a high prevalence of lower extremity arterial disease. In this patient population, screening for lower extremity arterial disease can be reserved for those with signs or symptoms of peripheral ischemia. Noninvasive carotid screening is justified in patients with renal artery disease to detect asymptomatic lesions that require either immediate surgical treatment or serial follow-up for disease progression.  相似文献   
996.
Caregivers of patients diagnosed with Alzheimer's disease (AD) are often advised to modify their speech to facilitate the patients' sentence comprehension. Three common recommendations are to (a) speak in simple sentences, (b) speak slowly, and (c) repeat one's utterance, using the same words. These three speech modifications were experimentally manipulated in order to investigate their individual and combined effects on sentence comprehension in AD. Fifteen patients with mild to moderate AD and 20 healthy older persons were tested on a sentence comprehension task with sentences varying in terms of (a) degree of grammatical complexity, (b) rate of presentation (normal vs. slow), and (c) form of repetition (verbatim vs. paraphrase). The results indicated a significant decline in sentence comprehension for the AD group. Sentence comprehension improved, however, after the sentence was repeated in either verbatim or paraphrased form. However, the patients' comprehension did not improve for sentences presented at the slow speech rate. This pattern of results is explained vis-à-vis the patients' working memory loss. The findings challenge the appropriateness of several clinical recommendations. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
997.
To improve the blood supply of the pedicled flap we have performed an additional microvascular augmentation to this type of breast reconstruction procedure since 1991. The ipsilateral deep inferior epigastric pedicle is anastomosed to the internal mammary artery and vein (IMAV supercharge). In 19 of 20 patients this technique proved to be feasible. For the venous anastomoses the 3M microvascular anastomosis system facilitated the procedure. In one patient the venous anastomosis failed due to the small calibre of two internal mammary veins. In a majority of the cases rapid improvement of flap perfusion could be observed as the direct result of the supercharging. The IMAV supercharged flap is quite comparable with the free flap as regards to the operative procedure. Disadvantages are a slightly more extensive dissection and less freedom in positioning the flap due to the presence of the superior muscular pedicle. The main advantage is that the supercharge procedure minimises the risk of total flap loss. Further technical improvement may be obtained by the use of a contralateral vascular pedicle dissected with muscle-sparing techniques.  相似文献   
998.
An echocardiographical and clinical pathological investigation of the rapid loss of weight by a yearling thoroughbred filly revealed an atrial septal defect, a ventricular septal defect and hyperfibrinogenaemia. A post mortem examination confirmed the cardiac abnormalities and revealed a severe thoracic aortitis. It is proposed that the idiopathic thoracic aortitis contributed to the horse's compromised cardiovascular homoeostasis.  相似文献   
999.
1000.
EB 1089 is a novel vitamin D analogue which in vitro strongly inhibits the proliferation of U937 histiocytic lymphoma cells and MCF-7 breast cancer cells, with a potency of 50 to 100 times that of 1,25-dihydroxyvitamin D3 [1,25(OH)2D3]. Studies of c-myc and c-fos expression in MCF-7 cells and of differentiation markers in U937 cells show that growth inhibition by EB 1089 is accompanied by induction of differentiation. The ability of EB 1089 to affect calcium metabolism in vivo in rats is decreased, compared to 1,25(OH)2D3. This low calcemic effect combined with the strong biological effect on cancer cells in vitro, makes EB 1089 an interesting candidate for treatment of cancer.  相似文献   
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