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Studies have shown a high correlation between measurements of bone mineral density (BMD) obtained on differentdual-energy X-ray absorptiometry machines. Challenger osteodensitometers (Diagnostic Medical System [DMS],Montpellier, France) are becoming widely used but little is known about their clinical performance. The aim of this study was to compare BMD measurements and the resulting patient classification based on T-scores obtained on a DMS Challenger device to those obtained on Hologic 4500A (Bedford, MA) device. Fifty-three volunteers were studied.The BMD of the spine and of the hip were simultaneously measured on both densitometers. BMD values obtained on the Challenger were significantly higher than those obtained with the Hologic QDR4500 (p<0.001). The correlations coefficients between the Hologic QDR4500 and the DMS Challenger measured BMDs were r=0.70 at the femoral neck, r=0.70 at the trochanter, and r=0.83 at the spine (p<0.001). Among the 35 postmenopausal women, there was discordance in the WHO T-score-based classification in 28 subjects (80%) at the spine, 18 subjects (52%) at the femoral neck, and 14 subjects (42%) at the trochanter. The intermachine agreement was low: The kappa score was -0.10 at the spine, 0.2 at the femoral neck, and 0.3 at the trochanter. In conclusion, this study cautions against the use of non established densitometers that leads to underdiagnosis of patients and, subsequently, to inappropriate treatment strategies.  相似文献   
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BACKGROUND: The deliberate use of ketoconazole to reduce the need for cyclosporine (CsA) is not new, but it is particularly relevant because of the high cost of CsA. Many studies have documented this benefit in renal and cardiac transplants, but this co-administration has not been reported in patients with nephrotic syndrome. METHODS: This retrospective study included 207 nephrotic patients who were steroid resistant, dependent or frequent relapsers and received CsA therapy. Among these patients 153 received daily ketoconazole therapy in a dose of 50 mg with concomitant decrease of one-third of the CsA dose while 54 patients received CsA alone. The majority of our cases were children (179 were below 18 years) and male to female ratio was 1.7:1. RESULTS: The great majority of the study population received the drugs for 1-2 years. Patients who received CsA and ketoconazole were comparable with those who received CsA alone regarding age, sex, duration of renal disease, renal pathology, severity of nephrotic syndrome, renal function, hepatic function and steroid response. Co-administration of ketoconazole significantly reduced mean doses of CsA by 37% after 1 month and 47% at 1 year with overall net cost savings of 37%. Hepatic functions remained within the normal range in both groups. Additionally, co-administration of ketoconazole significantly improved the response to CsA therapy, successful steroid withdrawal and decreased the frequency of renal impairment. CONCLUSIONS: Co-administration of keto with CsA in idiopathic nephrotic patients significantly reduces CsA costs and may improve its response.  相似文献   
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Twenty-five rabbits were used to study the effect of glossopharyngeal nerve transection upon the number, size and cellular constitution of the taste buds. The glossopharyngeal nerve was cut on one side, the other being left undisturbed as a control. The animals were sacrificed in groups of three after 7, 10, 14, 21, and 30 days, and 2 and 4 months after the operation. Seven days after the operation the size and number of intragemmal cells were decreased in the taste buds. The taste pores with hairlets passing through them disappeared. The number of taste buds on circumvallate papillae decreased. After ten days taste buds in both types of papillae showed signs of degeneration. Fourteen days after the operation there was a marked decrease in size and number of taste buds. The circumvallate papillae now possessed no taste buds. After 21 days few taste buds were present in foliate gutters. These consisted of one or two sustentacular cells each. After 30 days there were no taste buds on foliate papillae, and thickness of the epithelium lining the gutters was decreased. Two or four months after denervation, the foliate gutters were shallow and some had become flattened. The importance of the gustatory nerve for development and maintenance of the normal status of the taste buds is discussed.  相似文献   
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Background  

Rosai-Dorfman Disease is an uncommon benign systemic histio-proliferative disease. This is the first time the disease, although more common in people of African descent, is described in association with Sickle cell disease.  相似文献   
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The etiological role of human papillomavirus (HPV) in esophageal carcinoma (EC) in relation to p53, mdm2, p21(waf), c-erbB2 and the overall survival (OS) rate was investigated. Tumor and normal tissues from 50 EC were evaluated by polymerase chain reaction and InnoLiPA for HPV. Single strand conformation polymorphism/sequencing were used to detect p53 gene mutations. Immunohistochemistry was performed to determine p53, mdm2, p21(waf)and c-erbB2 expression. Human papillomavirus was detected in 54% of tumors and in 24% of normal tissues. p53, mdm2 and c-erbB2 overexpression was detected in 68%, 70% and 60% of tumors and in 14%, 16% and 10% of normal samples, whereas loss of p21(waf) was evident in 64% of tumors. p53 mutations were detected in 20% of cases. Exon 8 and 5 showed the highest mutation rate (40% each), followed by exons 6 and 7 (10% each). There was a significant correlation between HPV and p53, mdm2, c-erbB2 overexpression. The OS was significantly associated with overexpression of p53 and loss of p21(waf). Human papillomavirus infection is frequent in Egyptian EC. Both p53-dependent and p53-independent pathways seem to be involved in HPV-associated EC. mdm2 and c-erbB2 are possible targets for HPV in the p53-independent pathway. However, only advanced stage and aberrant expression of p53 and p21(waf) are independent prognostic markers.  相似文献   
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Rapid eye movement (REM) sleep deprivation has previously been shown to interfere with normal learning and memory and to inhibit long-term potentiation (LTP) in vitro. Previous studies on REM sleep deprivation and LTP have relied on in vitro analysis in isolated brain slices taken from animals following several days of sleep deprivation. LTP in the hippocampus in situ may differ from LTP in vitro due to modulatory inputs from other brain regions, which are altered after REM sleep deprivation. Here, we examined LTP in unanesthetized, behaving animals on the first and second recovery days following REM sleep deprivation to determine if similar effects are seen in vivo as previously reported in vitro. We found that LTP was significantly impaired in REM sleep-deprived animals on the second recovery day but not the first recovery day. Our results extend previous findings by showing that REM sleep deprivation continues to affect hippocampal function for more than 24h following the end of deprivation. Our results also suggest the presence of a modulatory process not present in vitro. Our findings are not explained by stress during REM sleep deprivation because equivalent circulating corticosterone levels (an index of stress) were found during both REM sleep deprivation and control treatment.  相似文献   
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3,4-Diphenyl-5-cyanopyridazin-6-one 3 was prepared from the reaction of cyano-acetamide2 with benzilhydrazone in dry pyridine. A series of its derivatives was prepared. Tolyl and benzene sulphonyl derivatives6a and6b are also prepared. 3,4-Diphenyl-5-cyano-pyridazin-6-thione5 was obtained from3 by the action of P2S5 while 3,4-diphenyl-5-cyano-6-chloropyridazine4 was obtained from3 by the action of POCl3. The reaction of4 with hydrazine hydrate directly afforded the pyrazolopyridazine derivative7. Compound4 also reacted with phenylhydrazine, aniline, thiophenol and anthranilic acid to yield pyridazine derivatives8, 9, 10 and11, respectively. On treatment of compound11 with acetic anhydride it cyclised to afford pyridazino pyrimidine derivatives12.  相似文献   
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