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排序方式: 共有1654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
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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.
4.
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   
5.
BACKGROUND: The effect of mitral valve morphology (MVM) on the long-term results of mitral balloon valvuloplasty (MBV) is not well established. The aim of the study was to evaluate the impact of MVM on long-term outcome of MBV. METHODS: Five hundred and eighteen consecutive patients (mean age, 31+/-11 years) who underwent successful MBV were followed up for 0.5-16.5 (mean, 6+/-4.5) years. Patients were divided into two groups according to their mitral echo score (MES) before MBV: group A (n=340; MES8). RESULTS: We report the immediate and long-term clinical and echocardiographic results of the above-mentioned 518 consecutive patients. The mitral valve area was significantly larger in group A than in group B, both immediately after MBV (2.0+/-0.3 vs. 1.82+/-0.3 cm2, respectively; P<0.0001) and also at the last follow-up (1.8+/-0.33 vs. 1.5+/-0.33 cm2, respectively; P<0.0001). Restenosis occurred in 38/340 (11%) in group A vs. 73/178 (41%) in group B (P<0.0001). Actuarial freedom from restenosis at 5, 10, 15 years were 92+/-2%, 85+/-3%, 65+/-6% for group A vs. 72+/-4%, 44+/-5%, 9+/-6% for group B (P<0.001). Event-free survival rates at 5, 10, 15 years for group A were 93+/-1%, 88+/-2%, 66+/-6% vs. 82+/-3%, 59+/-6%, 8+/-7% for group B (P<0.0001). Stepwise Cox multivariate regression analysis identified MES, preprocedure functional class, and postprocedure mitral valve area相似文献   
6.
Hereditary thrombophilia is caused by various inherited disorders. Most lead to a familial tendency to recurrent venous, not arterial, thrombosis, usually at a young age, and with spontaneous onset. Most of the genetic defects known today affect the function of natural anticoagulant pathways, in particular, the protein C system. In this study, 602 (265 female, 337 male) patients with suspected thrombosis, arterial or venous, were referred to King Hussein Medical Center in Amman, Jordan. The prevalence of hereditary deficiencies of antithrombin (AT), protein S (PS), and protein C (PC) were studied over a seven-year period (1993-2000). Activated protein C (APC-R) resistance subjects were studied over four years (1996-2000). The mean age was 30 years in females and 42 years in males. A diagnosis was established in 22.4% (n = 135) of the subjects (20.3% venous, 2.1% arterial). Protein C deficiency was found in 3.8%, protein S deficiency in 2.3% and antithrombin deficiency in 1.4% of our sample group. An APC-R problem was seen in 23.0% (n = 89) of the surveyed population. Out of the APC-R patients, 75.0% had the DNA analysis of a factor V Leiden mutation present. Of the subjects found to have the mutation 87.0% were heterozygous and 13.0% were homozygous. These results confirm that APC-R, as a result of factor V Leiden mutation, is the most prevalent cause of thrombosis, and thrombophilia is related to venous, not arterial, thrombosis.  相似文献   
7.
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   
8.
Newly hatched White Leghorn male chicks were used in this study. Different doses of T3 (O.1 or 1 ppm) or TRH (1 or 5 ppm) were administered in the feed for an 8-week period. Chicken growth hormone (cGH) (10 μg/kg BW) was injected (i.v.) into a different group of chicks twice daily for 1 week starting at 7 weeks of age. A different group received both T3 (0.1 and 1 ppm) and cGH. Serum concentrations of T4, T3 and GH, antibody production against sheep red blood cells (SRBC) and Brucella Abortus (BA), and in vitro proliferative response of both T- and B-lymphocytes to mitogenic stimulation were measured. Supplementation of T3 (1 ppm) significantly lowered T4 and increased T3 concentrations. No effect of any hormone treatment on antibody production was observed. T3 supplementation and cGH injection alone or with T3 (0.1 ppm) significantly increased blastogenic response of lymphocytes to either Con-A or LPS mitogenic stimulation. It was concluded that T3 and GH are involved in lymphocyte activity of chickens.  相似文献   
9.
OBJECTIVE: To evaluate beta-endorphin secretion in euprolactinemic cases of luteal phase defect (LPD). DESIGN: Serial blood samples from the 18th to the 26th day of the menstrual cycle were assayed for beta-endorphin, progesterone (P), estradiol (E2), and prolactin (PRL) in cases of LPD and controls. Diagnosis of LPD was based on determinations of serum P and premenstrual endometrial biopsy. SETTING: From Cairo University Hospitals. PATIENT, PARTICIPANTS: Twenty-six women with LPD and 8 normal fertile women (controls) were chosen. INTERVENTIONS: None. MAIN OUTCOME MEASURES: beta-Endorphin, P, E2, and PRL concentrations were determined by the corresponding 125I radioimmunoassay. RESULTS: Plasma beta-endorphin level in cases of LPD varied from 2.58 to 9.14 pmol/L, whereas the level of controls varied from 2.41 to 5.57 pmol/L. The mean value of plasma beta-endorphin in cases of LPD was significantly higher than that of controls by 146% (P less than 0.0005). In spite of the significant decrease of serum P in cases of LPD, serum E2 level did not differ significantly from that of controls. CONCLUSION: The possible sources of beta-endorphin rise and its implication in the etiology of LPD are explained.  相似文献   
10.
Heat-shock protein synthesis by human polymorphonuclear cells   总被引:4,自引:0,他引:4  
Mature human neutrophils from peripheral blood are known to be capable of limited protein biosynthetic activity. We now show that these cells are inducible for heat-shock protein synthesis when placed in short-term culture. Synthesis of hsp70 and hsp85 as well as the response to various temperatures and the time course of induction were typical for mammalian cell systems. This heat-shock response was blocked by actinomycin D added before heat exposure. This demonstration that hsp genes can be activated by heat exposure of terminally differentiated neutrophils supports the hypothesis that gene activation can serve a physiological role in these cells and opens up the possibility that synthesis of other gene products is similarly inducible.  相似文献   
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