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21.
Priapism is an unusual and distressing complication of sickle cell anaemia and its management has been varied and generally unsatisfactory. We report priapism in a Libyan boy with sickle cell anaemia, managed successfully by blood transfusion.  相似文献   
22.
To assess the quality of papers presented at the annual conference of the Indial Society of Gastroenterology, a proforma was completed by selected assessors regarding the time taken to present the paper, the quality of the paper and other aspects of presentation. Forty-six papers were evaluated; fifteen of 38 (39%) papers took more than the prescribed time of 8 minutes; 10% were rated unsatisfactory in quality. The quality and content of slides were rated as unsatisfactory in 17% and 7% respectively. The quality and relevance of the questions asked from the floor were graded as unsatisfactory in 20% and 14% respectively. Of the responses from authors to these questions, 33% were graded as unsatisfactory. In all, 28 (61%) of 46 papers assessed were unsatisfactory on one or more counts. Thus, efforts are needed to improve the quality of papers presented and of their presentation.  相似文献   
23.
24.
We report a case of the heparin-induced thrombocy-topenia and thrombosis syndrome presenting with acute ischemia of a lower limb. The patient was successfully treated by withdrawal of heparin products, intraarterial urokinase, and platelet anti-aggregation therapy consisting of Dextran and aspirin.  相似文献   
25.
In a study of cytokine production ex vivo by Borrelia burgdorferi-stimulated peripheral blood mononuclear cells from 27 patients with culture-positive erythema migrans, production of inflammatory cytokines predominated, particularly gamma interferon and, to a lesser degree, tumor necrosis factor alpha. In contrast, with the exception of interleukin-13, anti-inflammatory cytokine production was negligible. Thus, B. burgdorferi antigens in early Lyme disease often induce a strong inflammatory response.  相似文献   
26.
Pancreatic adenocarcinoma can present with a vast spectrum of rare manifestations. It usually occurs after the age of 50 years, the peak incidence being in sixth and seventh decades. We report a previously asymptomatic subject of pancreatic adenocarcinoma who presented for the first time with massive upper gastrointestinal hemorrhage. Endoscopy revealed ruptured esophageal varices which were secondary to tumour-induced thrombosis of the portal vein. Besides the uncommon mode of presentation, the patient was unusual because of his young age. Further, he was non-icteric at the time of presentation and remained so throughout the clinical course despite having a large lesion in the head of the pancreas.  相似文献   
27.
The cytokine tumor necrosis factor was originally identified as a protein that kills tumor cells. So far, 18 distinct members of this family have been identified. All of them regulate cell survival, proliferation, differentiation, and cell death, also called apoptosis. The apoptosis induced by TNF, and other members of the family, for example, FasL, VEGI, and TRAIL is mediated through death receptors. The apoptotic signals by these cytokines are transduced by eight different death domain- (DD) containing receptors (TNFR1, also called DR1; Fas, also called DR2; DR3, DR4, DR5, DR6, NGFR, and EDAR). The intracellular portion of all these receptors contains a region approximately 80 amino acids long referred to as the death domain. Upon activation by its ligand, the DD recruits various proteins that mediate both death and proliferation of the cells. These proteins in turn recruit other proteins via their DDs or death effector domains. The actual destruction of the cell, however, is accomplished by serial activation of a family of proteases referred to as caspases. Cell death is negatively regulated by a family of proteins that includes decoy receptors, silencer of DD, sentrin, cellular FLICE inhibitory protein, cellular inhibitors of apoptosis, and survivin. This review is an attempt to describe how these negative and positive players of cell death perform a harmonious dance with each other.  相似文献   
28.
The interaction of highly purified recombinant human tumor necrosis factor-alpha (rTNF-alpha) with human polymorphonuclear neutrophils (PMNs) was investigated. Binding of 125I-rTNF-alpha to PMN reached maximum levels in 30 min at 37 degrees C and in 2 h at 4 degrees C. Scatchard analysis of competitive binding data indicated approximately 6000 receptor sites per cell and a Kd of 1.37 nM. Binding data at 37 degrees C indicated a rapid internalization of rTNF-alpha. Following this receptor-mediated interaction, recombinant TNF-alpha was found to inhibit the migration of PMNs under agarose and to enhance PMN production of superoxide anion (O-2) in a dose-dependent manner. Furthermore, rTNF-alpha-activated PMNs caused a marked disruption of human umbilical-vein-derived endothelial cell monolayers and caused inhibition of their proliferative activities. These data substantiate the role of TNF-alpha as an activator of PMN functions and indicate that PMN/TNF-alpha/endothelial cell interactions may play a major role in inflammatory reactions.  相似文献   
29.
Juvenile Xanthogranuloma is a non-langerhans cell histiocytosis characterized by yellowish cutaneous nodules that usually appear in early infancy and childhood. Intramuscular variant is a rare form, with only eight reported cases, and none reported in ala of nose. Sheets of histiocytes, few touton giant cells and infiltrative borders makes it susceptible to misdiagnosis as childhood sarcomas or lymphoproliferative disorders. Awareness of the lesion aided by immunohistochemistry helps in reaching the proper diagnosis.  相似文献   
30.
The aim of this study was to determine which human immunodeficiency virus type 1 (HIV-1) subtypes were circulating in Australia and to correlate the subtypes with risk factors associated with the acquisition of HIV-1 infection. DNA was extracted from peripheral blood mononuclear cells, and HIV-1 env genes were amplified and subtyped using heteroduplex mobility analysis, with selected samples sequenced and phylogenetic analysis performed. The HIV-1 env subtypes were determined for 141 samples, of which 40 were from female patients and 101 were from male patients; 13 samples were from children. Forty-seven patients were infected by homosexual or bisexual contact, 46 were infected through heterosexual contact, 21 were infected from injecting drug use (IDU), 13 were infected by vertical transmission, 8 were infected from nosocomial exposure, and 6 were infected by other modes of transmission, including exposure to blood products, ritualistic practices, and two cases of intrafamilial transmission. Five subtypes were detected; B (n = 104), A (n = 5), C (n = 17), E (CRF01_AE; n = 13), and G (n = 2). Subtype B predominated in HIV-1 acquired homosexually (94% of cases) and by IDU (100%), whereas non-subtype B infections were mostly seen in heterosexually (57%) or vertically (22%) acquired HIV-1 infections and were usually imported from Africa and Asia. Subtype B strains of group M viruses predominate in Australia in HIV-1 transmitted by homosexual or bisexual contact and IDU. However, non-B subtypes have been introduced, mostly acquired via heterosexual contact.  相似文献   
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