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Following its benchmark discovery, nitric oxide (NO) is nowknown to play important functional roles in a variety of physiologicalsystems. Within the vasculature, NO induces vasodilation, inhibitsplatelet aggregation, prevents neutrophil/platelet adhesionto endothelial cells, inhibits smooth muscle cell proliferationand migration, regulates programmed cell death (apoptosis) andmaintains endothelial cell barrier function. NO generated byneurons acts as a neurotransmitter, whereas NO generated bymacrophages in response to invading microbes acts as an antimicrobialagent. Because neurons, blood vessels and cells of the immunesystem are integral parts of the reproductive organs, and inview of the important functional role that NO plays in thosesystems, it is likely that NO is an important regulator of thebiology and physiology of the reproductive system. Indeed, inthe past 10 years, NO has established itself as a polyvalentmolecule which plays a decisive role in regulating multiplefunctions within the female as well as the male reproductivesystem. This review provides an overview of the role of NO invarious reproductive organs under physiological and pathologicalconditions.  相似文献   
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PKD1 is the major locus of the common genetic disorder autosomal dominant polycystic kidney disease (ADPKD). Analysis of the predicted protein sequence of the human PKD1 gene, polycystin, shows a large molecule with a unique arrangement of extracellular domains and multiple putative transmembrane regions. The precise function of polycystin remains unclear with a paucity of mutations to define key structural and functional domains. To refine the structure of this protein we have cloned the genomic region encoding the Fugu PKD1 gene. Fugu PKD1 spans 36 kb of genomic DNA and has greater complexity with 54 exons compared with 46 in man. Comparative analysis of the predicted protein sequences shows a lower level of homology than in similar studies with identity of 40 and 59% similarity. However key structural motifs including leucine rich repeats (LRR), a C-type lectin and LDL-A like domains and 16 PKD repeats are maintained. A region of homology with the sea urchin REJ protein was also confirmed in Fugu but found to extend over 1000 amino acids. Several highly conserved intra- and extra- cellular regions, with no known sequence homologies, that are likely to be of functional importance were detected. The likely structure of the membrane associated region has been refined with similarity to the PKD2 protein and voltage gated Ca2+ and Na+ channels highlighted over part of this area. The overall protein structure has therefore been clarified and this comparative analysis derived structure will form the basis for the functional study of polycystin and its individual domains.   相似文献   
15.
The influence of purified natural colony stimulating factor-1 (CSF-1), purified recombinant granulocyte-macrophage (GM)-CSF, purified recombinant interleukin 3 (IL3) and natural IL3 were assessed in mice that were untreated or pretreated with purified iron-saturated human lactoferrin (LF) in order to first suppress myelopoiesis in the mice. S1/S1d mice responded to recombinant GM-CSF and recombinant IL3 in a manner similar to the response of their +/+ littermates. These 4 factors increased the cycling status of hematopoietic progenitors in vivo. The effects were more noticeable if myelopoiesis was first decreased by LF. The effects do not appear to be due to endotoxin contamination. It cannot be discerned from these studies whether the effects are direct ones on the progenitor cells or indirect ones mediated through growth-factor releasing accessory cells. It is possible that effects can be both direct and indirect.  相似文献   
16.
When plated in semi-solid media, PHA-stimulated human peripheral blood mononuclear cells (PBMC) form discrete T-cell colonies. By contrast, Sephadex G-10 non-adherent (NA) cells (greater than 96% T lymphocytes) show virtually no clonal growth unless cocultured with soluble factors derived from either normal adherent cells or tumour cell lines. Purified IL-1 was able to initiate colony growth of mitogen-stimulated NA cells; cultures containing 20 U of human IL-1 yielded colony counts that were only slightly less than those with PBMC. In addition, recombinant IL-2, free of measurable IL-1, was able to provide the initiating signal required for clonal expansion. Both recombinant and lymphocyte-derived IL-2 were able to enhance the clonal growth of PBMC. Colony growth could be initiated by supernatants derived from short-term cultures of either monocytic (U937, HL60) or B-cell (Raji, Daudi) tumour cell lines. The abilities of these tumour cell lines to promote clonal responses did not correlate with their contents of either IL-1 or IL-2. By contrast, supernatants derived from either K562 (an erythroleukaemic line) or MOLT 4 (a T-cell lymphoma) cells did not provide the initiating signal.  相似文献   
17.
Renal transplant (RT) is now a therapy of choice for end stage renal disease (ESRD). The Nephrology Unit, Asvini started functioning in Dec 90 and to date 1298 sittings of hemodialysis have been given to 45 patients. Of these, 35 were in ESRD and 11 patients underwent renal transplantation at this hospital during the period Jan 91 – Dec 93. One patient expired after 18 months of transplantation due to infection. Early experience in screening patients for RT, use of immunosuppression, management of rejection episodes and protocol are presented with special emphasis on its relevance to the Armed Forces.KEY WORDS: Transplantation, Renal Failure, Immunosuppression, Rejection  相似文献   
18.
Pediatric health screening procedures, both prenatal and postnatal, have a tremendous potential in improving the health status of children and in turn reducing the resource burden on the parents and the State. The existing recommendations, inherent problems and different screening procedures are discussed. The need for suitable mass screening pediatric procedures in the Indian context is stressed.KEY WORDS: Pediatric screening procedures  相似文献   
19.
BACKGROUND: To evaluate the efficacy and toxicity of cisplatin/etoposide continuous infusion chemotherapy for cancer of unknown primary site in Taiwan, a region with a high prevalence of endemic viral infections. METHOD: Between April 1994 and February 1996, 20 patients with a diagnosis of CUPS were treated, including 15 males and five females, of average age 63.3 years (range 41-83 years). Continuous intravenous infusion of etoposide 80 mg/m2 and cisplatin 25 mg/m2 was given for 3 days every 3 weeks. Pretreatment tumor marker and viral serology studies were performed for baseline evaluation. Nearly two-thirds of the patients had poorly differentiated carcinoma. The average number of metastatic sites was 2.65 (range 1-4), with liver and lymph node involvement predominating. RESULTS: The overall response rate was 25% (95% CI 17.7-32.3%); 30.7% for poorly differentiated cancers and 25% for well differentiated cancers. Median survival was 4 months (range 1-12 months), 4.8 months for patients attaining partial response. Toxicity was moderate, grade 3 and 4 neutropenia occurred in 55% and grade 3 and 4 thrombocytopenia in 40%; other toxicities were mild. CA125 and CA199 were elevated in more than 50% of patients. Viral serology studies were not significantly different from those of the indigenous population. CONCLUSION: Etoposide and cisplatin combination chemotherapy has modest activity in patients with extensive CUPS and, at the schedule and dosage given, it is associated with moderate toxicity.   相似文献   
20.
A 54-year-old man was treated with weekly 24-h infusion of high-dose 5-fluorouracil (2600 mg/m2) and leucovorin (100 mg/m2) for metastatic colon cancer. At first, he tolerated the treatment well and no significant toxicity was identified. After a total of eight courses of treatment, a stable disease was observed, but mild shortness of breath was found on occasion. The patient had no previous history of cardiac disease and the heart performance assessed by left ventricular ejection fraction before treatment was normal. Unfortunately, acute pulmonary edema with lethal cardiogenic shock occurred during the ninth course of treatment, in spite of intensive medical treatment. The chest X-ray showed extreme cardiomegaly. Repeated assessment of his heart function by echocardiogram and ventricular ejection fraction revealed a very poor cardiac performance. Toxic cardiogenic shock during weekly 24-h infusion of high-dose 5-fluorouracil and leucovorin is extremely rare. To the best of our knowledge, no case has been reported in the English literature. We report a case and the relevant literature about the incidence, clinical picture and possible pathophysiology on 5-fluorouracil-related cardioxicity is reviewed.   相似文献   
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