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排序方式: 共有1138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.
The optimal extent of resection for patients with stages I or II breast cancer treated with conservative surgery and radiotherapy.
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F A Vicini T J Eberlein J L Connolly A Recht A Abner S J Schnitt W Silen J R Harris 《Annals of surgery》1991,214(3):200-205
The optimal extent of breast resection before irradiation for treatment of early breast cancer has not been defined. Increasing the size of the resection may decrease the risk of local recurrence but will also have an adverse impact on the cosmetic outcome. The 5-year likelihood of a recurrence of the tumor was analyzed in relation to the volume of resected breast tissue in 507 patients with infiltrating ductal carcinoma treated with conservative surgery and radiation therapy between 1968 and 1982. Patients were stratified by clinical T-stage and for each T-stage patients were divided into three groups of equal numbers based on the volume of excised tissue. All patients had at least a gross excision of the tumor and the extent of breast resection was determined at the discretion of the surgeon without knowledge of the histologic features of the tumor. The median follow-up time was 100 months. The 5-year actuarial recurrence rates were analyzed in relation to clinical T-stage (T1 or T2) and the presence or absence of an extensive intraductal component (EIC+ or EIC-). For patients with EIC+ tumors, the largest resections were associated with a substantially lower risk of recurrence in the breast than the smallest resections. This effect was seen both for T1 tumors (10% versus 29%, p = 0.07) and for T2 tumors (9% versus 36%, p = 0.04). For patients with EIC-tumors, recurrence rates were significantly lower than for EIC+ tumors and were not influenced by the volume of resection to the same degree as EIC+ tumors. In the absence of an EIC, recurrence rates for the largest and smallest resections were 0% and 9% (p = 0.02) for T1 tumors and 3% and 6% (p = NS) for T2 tumors. It is concluded that a limited breast resection is acceptable for an EIC- tumor but that a more extensive resection is required for an EIC+ tumor. These results stress the importance of assessing the presence or absence of an EIC in determining the optimal extent of breast resection required before radiation therapy. 相似文献
5.
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
6.
7.
Alessia Bacchi Mauro Carcelli Giancarlo Pelizzi Paola Vicini 《Archiv der Pharmazie》1995,328(3):217-221
The amino/imino equilibrium is studied in free bases and hydrochloride salts of amidinobenzisothiazole derivatives by IR and 1H-NMR spectroscopy. The X-ray crystallographic analysis of two of these compounds shows that the free base exists as amino form whereas the hydrochloride as imino form. 相似文献
8.
Kynurenic acid inhibits the activation of kainic and N-methyl-D-aspartic acid-sensitive ionotropic receptors by a different mechanism 总被引:3,自引:0,他引:3
The action of kynurenic acid on currents elicited by the activation of amino acid receptors was investigated in primary cultures of cortical neurons prepared from neonatal rats. Kynurenic acid was tested on currents elicited by both N-methyl-D-aspartic acid (NMDA) and kainate, using patch-clamp recording techniques in "outside-out" and "whole-cell" configurations. The inhibition by kynurenic acid was compared with that elicited by amino-phosphono-valeric acid (APV). Whole-cell currents, elicited by increasing doses of NMDA, were antagonized competitively by APV and non-competitively by kynurenic acid (ID50 70 microM); in contrast, kynurenic acid inhibited competitively the whole-cell currents elicited by kainic acid (ID50 500 microM). The non-competitive inhibition by kynurenic acid of the whole cell currents elicited by NMDA was antagonized competitively by glycine, a specific positive allosteric modulator of NMDA receptors; on the other hand glycine failed to change the inhibition by APV of the NMDA-elicited responses. Thus, kynurenic acid inhibits NMDA receptors allosterically (non-competitively) and kainic acid receptors isosterically (competitively). 相似文献
9.
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
10.
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