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排序方式: 共有745条查询结果,搜索用时 15 毫秒
1.
Needle-localized breast biopsy: why do we fail? 总被引:10,自引:0,他引:10
2.
J. Duteil FA Rambert AM Pointeau P. Mangiameli and E. Assous 《Fundamental & clinical pharmacology》1991,5(8):695-708
The potential antidepressant effect of flerobuterol (dl-(fluoro-2 phenyl)-1 t-butylamino-2 ethanol), a new drug related to beta-adrenoceptor agonists, was evaluated and compared with imipramine and salbutamol using classical psychopharmacological tests in mice. Like imipramine and salbutamol, flerobuterol (0.5-32 mg kg-1, ip) fully prevented apomorphine (16 mg kg-1, sc)- and partly reversed reserpine- and oxotremorine-induced hypothermia. At higher doses (16-32 mg kg-1), flerobuterol enhanced the toxic effects of yohimbine. Unlike imipramine, flerobuterol and salbutamol did not reduce immobility duration in the behavioural despair test. Salbutamol and flerobuterol decreased locomotor activity. Flerobuterol did not induce mydriasis, did not prevent oxotremorine-induced tremors or salivary and lacrimal gland secretion and did not reduce reserpine-induced palpebral ptosis. Propranolol (8 mg kg-1, ip) but not alpha-methyl-paratyrosine (75 mg kg-1, ip) prevented the flerobuterol-induced antagonism of apomorphine-induced hypothermia. Our results suggest that flerobuterol demonstrates potential antidepressant activity, which could be related to beta-adrenoceptor activation in mice. 相似文献
3.
Suppurative corneal ulceration in Bangladesh 总被引:8,自引:0,他引:8
AAS Dunlop MB BS ED Wright MRCPath † SA Howlader‡ I Nazrul‡ R Husain‡ K McClellan FRACO § FA Billson FRACO § 《Clinical & experimental ophthalmology》1994,22(2):105-110
Suppurative keratitis is an important preventable cause of blindness, particularly in the developing world. This study analyses 142 cases of suppurative keratitis referred to Chittagong Eye Infirmary, Bangladesh. Some 53.5% of cases were bacterial and 35.9% were fungal. The five most common pathogens were: Pseudomonas sp. 24%, Streptococcus pneumoniae 17%, Aspergillus sp. 13%, Fusarium sp. 7% and Curvularia sp. 6%. Gram stain and culture results were consistent in 62.6% of cases. Previous antibiotic treatment was a significant factor for failure of culture isolation and less so for Gram stain failure. On Gram stain, 55.9% of pseudomonal cases were missed, but only 2% of fungal cases were missed. Over all, Gram stain had a sensitivity of 62% and positive predictive value of 84% for bacterial cases, and 98% and 94% for fungal cases, respectively. Fungal ulcers were typically filamentous, but an antecedent history of trauma was not common. The most frequent injury was due to rice grains, but the inoculum appeared to be introduced during eye washing with contaminated water. Pseudomonal ulcers occurred most frequently in the monsoon season, and Fusarium cases were seen only in the hot, dry season. 相似文献
4.
科室主任管理职能与基本素质探讨 总被引:11,自引:3,他引:8
人力资源在管理中发挥着重要作用,其中,科室主任作为医院人力资源的重要组成部分,在医院惯性运行和可持续发展中扮演着重要角色。因此,科室主任因其技术和管理双重职责所具备的管理职能、基本素质和领导艺术在日常工作中显得尤为关键。 相似文献
5.
6.
Systemic injection of products of activated neutrophils and H2O2 in myeloperoxidase-immunized rats leads to necrotizing vasculitis in the lungs and gut. 总被引:1,自引:0,他引:1 下载免费PDF全文
P. Heeringa P. Foucher P. A. Klok M. G. Huitema J. W. Tervaert J. J. Weening C. G. Kallenberg 《The American journal of pathology》1997,151(1):131-140
The strong association of anti-neutrophil cytoplasmic antibodies with various forms of systemic vasculitis suggests a role for these autoantibodies in the pathophysiology of systemic vasculitis. In the present study, we tested the hypothesis that release of neutrophil lysosomal enzymes in the presence of an anti-myeloperoxidase (anti-MPO) immune response may underlie the development of systemic vasculitis. Brown Norway rats were immunized with MPO in complete Freund's adjuvant or complete Freund's adjuvant alone. Two weeks after immunization, rats bad developed antibodies to human and rat MPO as measured by enzyme-linked immunosorbent assay. Next, rats were intravenously infused with 400 micrograms of a human neutrophil lysosomal extract containing 200 micrograms of MPO followed by 0.5 ml of a 1 mmol/L solution of H2O2 through a cannula inserted into the right jugular vein. Rats were sacrificed at 4 hours, 24 hours, 7 days, or 14 days, and several organs (lungs, heart, liver, spleen, gut, and kidneys) were examined for vasculitic lesions and inflammatory cell infiltrates. Macroscopically, patchy hemorrhagic spots were observed in the lungs and gut of MPO-immunized rats at days 7 and 14 after systemic infection of the neutrophil lysosomal extract and H2O2. Such changes were not observed at earlier time points or in control immunized rats. Histologically, the lungs of MPO-immunized rats sacrificed at days 7 and 14 showed patchy inflammatory cell infiltrates associated with vasculitis, granuloma formation, giant cells, and foci of hemorrhage. At 14 days, early signs of fibrosis were found with deposition of collagen and proliferation of fibroblasts. Furthermore, a prominent leukocytoclastic vasculitis was found in the small intestine of these rats characterized by fibrinoid necrosis and an extensive neutrophilic infiltrate. No inflammatory changes were found in the other organs studied (heart, liver, spleen, and kidneys). Control immunized rats, sacrificed at days 7 and 14 showed only some small foci of inflammatory infiltrates in the lungs whereas no inflammatory changes were found in the gastrointestinal tract. These studies show that release of products from activated neutrophils in the presence of anti-MPO autoantibodies may be relevant to the pathogenesis of anti-MPO-associated vasculitides. 相似文献
7.
Targeted gene disruption of murine CD7 总被引:2,自引:0,他引:2
CD7 is a 40 kDa type I transmembrane glycoprotein member of the Ig
superfamily. CD7 is a marker of mature human T cells and NK cells, and is
expressed early in their development. Cross-linking CD7 positively
modulates T cell and NK cell activity as measured by calcium fluxes,
expression of adhesion molecules, cytokine secretion and proliferation. CD7
associates directly with phosphoinositol 3'-kinase, and CD7 ligation
induces production of D-3 phosphoinositides and tyrosine phosphorylation.
Severe combined immunodeficiency has been associated with a lack of
lymphocyte surface CD7. The CD7 ligand is unknown. The murine CD7 homolog
is encoded by a single gene on chromosome 11. In order to characterize the
role of CD7 in lymphocyte development and function we have eliminated the
CD7 gene by targeted disruption. CD7- deficient mice display normal
histology of thymus and spleen, normal lymphocyte populations in primary
and secondary lymphoid tissues, and normal serum Ig levels. Specific
antibody responses after immunization with T-dependent and T-independent
antigens are equivalent in wild-type and CD7 knockout mice. CD7-deficient
lymphocytes respond normally to T cell mitogenic and allogeneic stimuli,
and display normal NK cell cytotoxicity.
相似文献
8.
Ghazzawi IM; Sarraf MG; Taher MR; Khalifa FA 《Human reproduction (Oxford, England)》1998,13(2):348-352
A prospective study was carried out to compare the fertilizing capability
and pregnancy outcome following intracytoplasmic sperm injection (ICSI)
using spermatozoa obtained from ejaculates, or surgically from epididymis
or seminiferous tubules. A total of 77 ICSI cycles (one per patient) was
included. In all, 28 patients had severe oligoasthenoteratozoospermia, 19
patients had obstructive azoospermia and 30 patients had non-obstructive
azoospermia. The main outcome measures were fertilization rate per injected
metaphase II oocyte and the clinical pregnancy rate per embryo transferred
back to the female recipients. In patients with severe
oligoasthenoteratozoospermia, the fertilization and pregnancy rates were 79
and 25 %. In patients with obstructive azoospermia, for whom epididymal
spermatozoa were used, these were 75 and 28%, and in the non-obstructive
group for which testicular spermatozoa were used for injection, they were
69 and 21% respectively. These rates were not significantly different in
the three groups (P = 0.85 and P = 0.14 respectively), suggesting that
spermatozoa from the ejaculates and epididymal or testicular biopsies are
able to fertilize equally by using ICSI. Live birth per embryo transfer was
significantly reduced in patients with non-obstructive azoospermia compared
to the other two groups. The high abortion rate (50%) in the group in which
testicular spermatozoa were used raises doubts about the developmental
competence of such embryos.
相似文献
9.
Zandvoort A Lodewijk ME Klok PA Breukels MA Rijkers GT Timens W 《Clinical and experimental immunology》2003,131(1):8-16
Chemotherapy has, besides the beneficial effects, several adverse effects. Suppression of the immune system is one of the most important problems. Infections caused by encapsulated bacteria like Streptococcus pneumoniae are responsible for a major part of infectious problems during and after treatment. The splenic marginal zone is essential in the initiation of an immune response to encapsulated bacteria. In this study, we analysed the effects of three different cytostatic agents on humoral immune responses. We found a reduced, but detectable immune response capacity at two days after treatment although the marginal zone B cell population is severely reduced at this time point. Twenty-four days after cessation of treatment, the immune response capacity was largely restored although lymphoid compartments were still not completely restored at that time point. Apparently, the presence of only few marginal zone B cells is sufficient to evoke a rise in antibody titres and although antibody titre increases are low, even small rises are most likely clinically relevant. 相似文献
10.
The ileoanal J pouch: radiographic evaluation 总被引:1,自引:0,他引:1
Endorectal ileoanal pull-through offers an attractive alternative to proctocolectomy and ileostomy for patients with ulcerative colitis, Gardner syndrome, and familial polyposis. To our knowledge, a careful radiographic analysis of the ileum, ileal pouch, and ileoanal anastomosis after ileoanal pull-through has not been reported. Thirty-two patients with ulcerative colitis, Gardner syndrome, and familial polyposis underwent colectomy, mucosal proctectomy, and endorectal ileoanal pull-through of a 15-cm ileal "J" pouch and loop ileostomy. Twenty-five (78%) of 32 of all the pouches radiographically demonstrated spiral folds extending from the middle of the pouch to the pectinate line. Other radiographic features included a mesenteric mass effect, pseudopolyps, and a central lucency that indicated intrapouch sutures. Radiographs provide useful information in the postoperative management of the ileal pull-through. 相似文献