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排序方式: 共有817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  
Jackman  RJ; Marzoni  FA  Jr 《Radiology》1997,204(3):677
  相似文献   
2.
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  
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.
We hypothesized that in congestive heart failure (CHF) slow-twitch but not fast-twitch muscles exhibit decreased fatigue resistance in the sense of accelerated reduction of muscle force during activity. Experiments were carried out on anaesthetized rats 6 weeks after induction of myocardial infarction or a sham operation (Sham). Animals with left ventricular end-diastolic pressure (LVEDP) > 15 mmHg under anaesthesia were selected for the CHF group. There was no muscle atrophy in CHF. Force generation by in situ perfused soleus (Sol) or extensor digitorum longus (EDL) muscles was recorded during stimulation (trains at 5 Hz for 6 s (Sol) or 10 Hz for 1.5 s (EDL) at 10 or 2.5 s intervals, respectively) for 1 h in Sol and 10 min in EDL at 37 °C. Initial force was almost the same in Sol from CHF and Sham rats, but relaxation was slower in CHF. Relaxation times (95–5 % of peak force) were 177 ± 55 and 131 ± 44 ms in CHF and Sham, respectively, following the first stimulation train. After 2 min of stimulation the muscles transiently became slower and maximum relaxation times were 264 ± 71 and 220 ± 45 ms in CHF and Sham, respectively (   P < 0.05  ). After 60 min they recovered to 204 ± 60 and 122 ± 55 ms in CHF and Sham, respectively (   P < 0.05  ). In CHF but not in Sham rats the force of contraction of Sol declined from the second to the sixtieth minute to 70 % of peak force. The EDL of both CHF and Sham fatigued to 24–28 % of initial force, but no differences in contractility pattern were detected. Thus, slow-twitch muscle is severely affected in CHF by slower than normal relaxation and significantly reduced fatigue resistance, which may explain the sensation of both muscle stiffness and fatigue in CHF patients.  相似文献   
6.
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.
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.
The ileoanal J pouch: radiographic evaluation   总被引:1,自引:0,他引:1  
Hillard  AE; Mann  FA; Becker  JM; Nelson  JA 《Radiology》1985,155(3):591-594
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   
10.

Objective

To investigate age and sex differences in the utilisation of hospital services for ischaemic heart disease.

Design

Analysis of routine mortality data and hospital activity data.

Setting

South West Thames Regional Health Authority.

Subjects

Residents of the South West Thames Regional Health Authority who in 1991 either died from ischaemic heart disease or were admitted to an NHS hospital in England and Wales with a main diagnosis of ischaemic heart disease.

Main outcome measures

Ratio of consultant episodes to deaths from ischaemic heart disease (as a proxymeasure of the utilisation of hospital care), and the percentages of consultant episodes in which further investigation (angiography or catheterisation) or revascularisation treatment (coronary artery bypass grafting or angioplasty) were carried out.

Results

The ratio of episodes to deaths was similar in men and women (odds ratio for men vs. women 0.96, 95% confidence intervals 0.90 to 1.03). The percentage of episodes in which further investigation was carried out was higher in men than women (odds ratio for men vs. women 1.46, 95% confidence intervals 1.25 to 1.70) as was the percentage of episodes in which revascularisation treatment was carried out (odds ratio for men vs. women 1.46, 95% confidence intervals 1.20 to 1.77). The ratio of episodes to deaths, the percentage of episodes in which further investigation was carried out, and the percentage of episodes in which revascularisation treatment was carried out all declined with age (all p values <0.001).

Conclusions

Women with ischaemic heart disease are as likely as men to be admitted to hospital, but afteradmission are less likely to undergo further investigation and revascularisation treatment. Elderly patients with ischaemic heart disease are less likely than younger patients to be admitted to hospital; after admission, they are also less likely to undergo further investigation and revascularisation treatment. Further research is needed to determine whether these age and sex differences in the use of hospital services are clinically justified.  相似文献   
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