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1.
Mubin I Syed Najeeb Chaudhry Azim Shaikh Kamal Morar Kumar Mukerjee Earl Damallie 《Journal canadien de gastroenterologie》2007,21(2):117-123
Over the past 10 years, arteriography has become a well-established technique for the diagnosis of acute lower gastrointestinal bleeding, but not particularly for rectal bleeding. However, to the authors' knowledge, the technique of middle hemorrhoidal artery embolization has rarely been reported in the literature. In the present report, three patients with life-threatening rectal bleeding are presented, which was controlled by superselective embolization of the middle hemorrhoidal artery or selective embolization of the internal iliac artery as a last resort. 相似文献
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3.
S. Shaikh D. A. Collier P. Sham L. Pilowsky T. Sharma L. K. Lin M. A. Crocq M. Gill R. Kerwin 《American journal of medical genetics. Part A》1995,60(6):541-545
We have examined the hypothesis that a variable number of tandem repeats in the third cytoplasmic loop of the dopamine D4 receptor influences clinical response to clozapine using a sample of 189 schizophrenic patients. Alleles of the 48-bp repeat, which range from two to ten copies in the normal human population, were analysed by the polymerase chain reaction using genomic DNA as template. Association between these alleles and response to clozapine was tested using the difference in pre-and post-treatment GAS scores as a measure of response. We found no statistically significant variation between genotypic groups and response by analysis of variance. We conclude that the variation of the number of 48-bp repeats alone does not determine response to clozapine. Larger studies are underway to determine if there is a more subtle relationship with sequence variation within the repeats or at other polymorphic sites within the gene that may provide evidence for a component of clozapine's action being at D4 receptors. © 1995 Wiley-Liss, Inc. 相似文献
4.
Linkage studies and mutation analysis of the PDEB gene in 23 families with Leber congenital amaurosis. 总被引:1,自引:0,他引:1
The phenotype in the rd mouse is similar to the clinical presentation of Leber congenital amaurosis (LCA) in humans. Recently a nonsense mutation in the beta subunit of the cGMP phosphodiesterase (Pdeb) gene has been defined as the cause for the rd phenotype in the mouse and has raised the question as to whether mutations in the human PDEB gene might cause LCA. We have previously cloned and characterized the human homologue of the mouse Pdeb gene and have mapped it to chromosome 4p16.3. In this study, a total of 23 LCA families of various ethnic backgrounds have been investigated. Linkage analysis using highly polymorphic (CA)n microsatellites has excluded the PDEB gene as a cause for LCA in 6 families. In the remaining 17 families, we have searched for mutations in the 22 exons of the PDEB gene using single-strand gel electrophoresis (SSGE). Multiple exonic polymorphisms have been determined. However, no DNA changes in the PDEB gene have been identified in our study population which could be causative for the LCA phenotype. 相似文献
5.
The effects of central infusion of naloxone into the midbrain periaqueductal gray (PAG) upon predatory attack behavior in the cat were studied in 12 cats. Initially, quiet biting attack was elicited by electrical stimulation of sites within the lateral hypothalamus using monopolar electrodes. Then cannula-electrodes were implanted into sites within the PAG from which electrical stimulation facilitated or suppressed the attack response. Following identification of modulatory sites within the PAG, naloxone (1.0 micrograms/0.5 microliter) was microinjected into those sites and the effects upon hypothalamically elicited attack were assessed. At nine of twelve sites in the PAG where suppression was obtained, administration of naloxone served to block those effects. Similarly, at six of eight facilitatory sites within the PAG, naloxone also blocked the modulatory effects of PAG stimulation. However, vehicle (isotonic saline) alone did not alter the modulatory effects of PAG stimulation. Administration of DAME (250 ng/0.3 microliter) into PAG modulatory sites in four cats, two which facilitated and two that suppressed the attack response, reversed the effects of naloxone at these sites. These results demonstrate that opioid peptides within the PAG play a complex role in the expression of predatory attack behavior in the cat. 相似文献
6.
W. A. Shaikh 《Allergy》1992,47(4):327-330
Inhaled beclomethasone dipropionate (BDP) has been used with few side effects in the treatment of bronchial asthma for 2 decades. Until now the manifestation of tuberculosis (TB) in patients on inhaled BDP has not been reported. Eight patients with allergic asthma, of a total of 548 asthmatics (1.46%) seen over a 2-year period, developed active TB following the use of inhaled BDP. All were sputum-positive for acid-fast bacilli (AFB) on smear and/or culture, all responded well to a combination of anti-TB drugs, and none showed evidence of immunological or pituitary-adrenal suppression. Two patients agreed to a repeat administration of BDP; both developed TB again within 2 weeks and are again on anti-TB treatment. 相似文献
7.
A patient with rheumatic mitral valve stenosis and regurgitation presented with shortness of breath and a "noise" in her chest. Cardiac auscultation revealed an intermittent late systolic "whoop." An increase in severity of mitral valve insufficiency during the periods of "whoop" was observed by pulsed Doppler, hemodynamic tracings and left ventriculography. 相似文献
8.
Shinkai T De Luca V Zai G Shaikh S Matsumoto C Arnold PD Hwang R King N Trakalo J Potapova N Wong G Hori H Wong AH Ohmori O Nakamura J Kennedy JL 《Psychiatric genetics》2004,14(3):177-180
OBJECTIVE: Oxidative stress such as free radical-mediated neuronal dysfunction may be involved in the pathophysiology of schizophrenia. The human glutathione peroxidase (GPX1) is a selenium-dependent enzyme, which plays an important role in the detoxification of free radicals. We therefore hypothesized that the GPX1 gene, which is located on chromosome 3p21.3, may be involved in the pathophysiology of schizophrenia. The aim of this study is to examine whether a potentially functional polymorphism, a proline (Pro) to leucine (Leu) substitution at codon 197 (Pro197Leu) of the human GPX1 gene, is associated with susceptibility to schizophrenia. METHODS: We genotyped the Pro197Leu polymorphism in a total of 113 nuclear families that had a proband with schizophrenia. Genetic association was tested using the transmission disequilibrium test (TDT), the sib transmission disequilibrium test (STDT), and the family-based association test (FBAT). RESULTS: The minor allele (Leu) frequency was calculated to be 0.282. We could not find significant transmission disequilibrium of the alleles for the Pro197Leu polymorphism in the GPX1 gene in association with the presence of schizophrenia in our family sample (TDT, chi2=0.03, degrees of freedom=1, P=0.86; combined TDT-STDT, Z'=-0.052, P=0.47; FBAT, Z=0.000, P=1.000). CONCLUSION: The results of this study suggest that the GPX1 polymorphism is unlikely to be associated with susceptibility to schizophrenia. 相似文献
9.
S Karmaker D Biswas N M Shaikh S K Chatterjee V K Kataria R Kumar 《Journal of medical microbiology》1991,34(3):149-151
Twenty isolates of Salmonella typhi from cases of typhoid during the 1989-1990 epidemic in Calcutta were examined. Most isolates (84% of all isolates in the epidemic) were resistant to chloramphenicol, ampicillin, tetracycline and streptomycin but were sensitive to nalidixic acid and ciprofloxacin. Plasmids of 120 kb and 14 kb were identified amongst the multi-drug resistant isolates of S. typhi. However, there was no plasmid in the antibiotic-sensitive isolates. The 120-kb plasmid was transferable and transconjugants were resistant to chloramphenicol, ampicillin, tetracycline and streptomycin. Restriction endonuclease analysis patterns after EcoRI digestion of the 120-kb antibiotic-resistance plasmids from the S. typhi isolates and transconjugants were similar. 相似文献
10.
Recombinant avian oncoviruses. II. Alterations in the gag proteins and evidence for intragenic recombination. 总被引:17,自引:0,他引:17
The internal structural (gag) proteins of recombinant avian oncoviruses selected for the env gene of RAV-O (an endogenous chicken virus) and the src gene for PR-RSV-C were examined. Eight of ten clones of such recombinants were found to synthesize altered gag proteins. The gag proteins of one recombinant clone, PR-E-95c, were examined in more detail by gel electrophoresis and tryptic peptide mapping. These methods have allowed us to distinguish between the gag proteins of the two parental viruses and to determine from which virus the proteins of the recombinant virus were derived. PR-E-95c virions were found to contain p270, an electrophoretically distinguishable variant of p27 which is found in isolates of RAV-0. This recombinant virus also contains p12/15, which is electrophoretically indistinguishable from the p12/15 of both of the parental viruses. However, tryptic peptide analysis of p15 indicates that PR-E-95c has inherited PR-RSV-C-specific p15 sequences. These observations suggest that at least one cross-over has occurred between p15 and p27 in PR-E-95c. A striking difference between the proteins of PR-E-95c virus and those of the parental viruses is that the recombinant lacks polypeptides migrating in the position of p19 and contains two novel polypeptides termed p19α (MW 20,000) and p19β (MW 15,000). Both of these polypeptides are phosphorylated and share antigenic determinants and some tryptic peptides with parental p19. As determined by peptide analysis and radioimmunoassay, these p19-related proteins contain information from both parental viruses, suggesting that PR-E-95c has another cross-over within p19. The altered p19 proteins bind to viral RNA specifically and are associated with genomic RNA in the virion. Neither the stability nor the specific infectivity of the recombinant viruses appears to be significantly affected by the altered proteins. 相似文献