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41.
42.
We evaluated the AMPLICOR cytomegalovirus (CMV) PCR kit for the diagnosis of neurologic CMV infections on 43 positive and 112 negative archived cerebrospinal fluid specimens originally tested by an in-house PCR method. The AMPLICOR kit showed sensitivity and specificity of 95 and 100%, respectively, versus the home-grown assay, indicating its utility in this clinical setting.  相似文献   
43.
44.
The role of pertussis toxin-sensitive G proteins on the alpha 2-adrenoceptor and mu-opioid receptor-mediated inhibition of the efferent function of capsaicin-sensitive neurones was investigated in guinea-pig atria pretreated with guanethidine. In the presence of atropine, CGP 20712A (2-hydroxy-5-(2-[hydroxy-3-(4-[(1-methyl- 4-trifluormethyl)1H-imidazol-2-yl]-phenoxy)propyl]aminoethoxyl+ ++)-benzamide) and prazosin, [D-Ala2,NMe-Phe4,Gly5-ol]enkephalin (DAGO, 0.1-3 microM) and 2-amino-6-allyl-5,6,7,8-tetrahydro-4H-thiazolo(4,5-d)azepine (BHT 920, 0.01-1 microM) reduced the positive inotropic effect induced by transmural stimulation of preparations obtained from control and from pertussis toxin-treated animals. These results suggest that pertussis toxin-sensitive G proteins are not involved in the inhibitory regulation of the efferent function of capsaicin-sensitive nerve terminals in cardiac tissue induced by alpha 2 and opioid receptor stimulation.  相似文献   
45.
A 13-year-old boy had complained of an asymptomatic swelling in the anterior maxilla for approximately 4 years. The patient reported no local trauma. The intra-oral examination revealed an exophytic lesion in the incisive papilla between the maxillary central and lateral incisor teeth. The radiographies detected no significant findings. Histopathologically, the lesion showed a dense fibrous tissue above the overlying mucosa. Bone ossification lay beneath a partially hypertrophic cartilage showing occasionally pleomorphic chondrocytes. Because of its microscopic aspects, heterotopic ossification may be mistaken for chondrosarcoma or other conditions involving periosteum, such as parosteal osteosarcoma. A case of heterotopic ossification in the anterior maxilla is presented, and clinicopathologic similarities with other osteochondromatous lesions are discussed.  相似文献   
46.
BACKGROUND: Spironolactone is useful in heart failure, but is not given to dialysis patients for fear of hyperkalaemia. This study evaluated the safety of spironolactone administration in haemodialysis patients. METHODS: Fifteen haemodialysis outpatients with mean serum potassium <5.6 mEq/l over the preceding 4 months were treated with spironolactone 25 mg daily for 28 days. Serum potassium was measured before every haemodialysis during the study. Aldosterone and renin were measured at the beginning and end of the study. Patients were monitored for side effects. Data were examined with a paired t-test, with patients serving as their own controls and P < 0.05 considered significant. A sample size of 14 was required to achieve a power of 0.8 and a P = 0.05 to detect a potassium difference of 0.5 +/- 0.6 mEq/l. All patients were analysed as intention-to-treat. RESULTS: The mean potassium level was 4.6 +/- 0.6 mEq/l at baseline and 4.9 +/- 0.9 mEq/l at study completion (P = 0.14). Thirteen patients completed the trial with no potassium levels >6.0 mEq/l. Four patients had potassium levels between 5.5 and 6.0 mEq/l. One patient was withdrawn at day 20 after developing hyperkalaemia (7.6 mEq/l). Another patient was withdrawn at day 25 after missing a dialysis treatment. There were no differences in either baseline or 28 day aldosterone or renin levels (16.8 +/- 28.8 vs 11.7 +/- 6.1 ng/dl and 3.5 +/- 3.9 vs 3.5 +/- 3.5 ng/ml/h, respectively). Infrequent side effects included dry mouth, nosebleed, pruritis, gynecomastia and diarrhoea. No significant leukopenia or anaemia was noted. CONCLUSIONS: Spironolactone may be considered as a treatment option for selected chronic haemodialysis patients with heart disease.  相似文献   
47.
In vitro human hepatocyte cultures are a key tool in the investigation of xenobiotic toxicity and metabolism. In most in vitro hepatocyte studies, the cells are allowed to adhere to an extracellular matrix, such as collagen. Unfortunately, the ability of freshly isolated hepatocytes to adhere to collagen varies from donor to donor. We used microarray analysis to determine what gene expression differences exist between hepatocytes in suspension and hepatocytes attached to collagen. Results from different donors showed a considerable difference in gene expression patterns between the two hepatocyte populations. In addition, we also compared the gene expression profiles of hepatocytes in culture with liver tissue. The results showed that both hepatocytes in suspension and hepatocytes attached to collagen display significant gene expression differences compared with liver tissue. Finally, we show that both populations of hepatocytes are responsive to dexamethasone and regulate some of the same genes. Overall, our results suggest that either significant gene expression changes occur in isolated hepatocytes or that suspended and attached cells represent different populations of hepatocytes found in intact livers.  相似文献   
48.
Hyperekplexia is a rare, autosomal dominant neurological disorder characterized by hypertonia, especially in infancy, and by an exaggerated startle response. This disorder is caused by mutations in the ?1 subunit of the inhibitory glycine receptor (GLRA1). We previously reported two GLRA1 point mutations detected in 4 unrelated hyperekplexia families; both mutations were at nucleotide 1192 and resulted in the replacement of Arg271 by a glutamine (R271Q) in one case and a leucine (R271L) in the other. Here, 5 additional hyperekplexia families are shown to have the most common G-to-A transition mutation at nucleotide 1192. Haplotype analysis using polymorphisms within and close to the GLRA1 locus suggests that this mutation has arisen at least twice (and possibly four times). In 2 additional families, a third mutation is also presented that changes a tyrosine at amino acid 279 to a cysteine (Y279C). Five patients with atypical clinical features and equivocal or absent family history of hyperekplexia and 1 patient with a classical presentation but no family history are presented in whom a mutation in the GLRA1 gene was not detected. Thus, only clinically typical hyperekplexia appears to be consistently associated with GLRA1 mutations, and these affect a specific extracellular domain of the protein.  相似文献   
49.
To assess the significance of diffuse cardiac activity (DCA) seen on In-111 labeled leukocyte scans, we reviewed 87 studies performed over the last 4 years. Inflammatory cardiac conditions were seen as frequently in patients with DCA (15%) as those without (7%, P=0.3). There was a higher ratio of RBC:WBC in the final WBC preparation in the false-positive DCA group than the true positive DCA and no DCA groups. False-positive studies showing DCA are most likely due to residual blood pool activity.Presented in part, 70th annual meeting, Radiological Society of North America, Washington D.C., 25 November 1984  相似文献   
50.
Sonography of testicular microlithiasis   总被引:1,自引:0,他引:1  
The sonographic appearance of testicular microlithiasis detected in a patient presenting with torsion is described. A "speckled" pattern of multiple, tiny bright echoes is produced by calcific concretions in the seminiferous tubules and seems to be characteristic of microlithiasis. Although this condition is not treatable, it should be recognized because it is often associated with extratesticular abnormalities and can obscure superimposed testicular disease.  相似文献   
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