首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   241篇
  免费   12篇
  国内免费   5篇
儿科学   15篇
妇产科学   3篇
基础医学   27篇
口腔科学   3篇
临床医学   18篇
内科学   55篇
皮肤病学   1篇
神经病学   4篇
特种医学   20篇
外科学   27篇
综合类   11篇
一般理论   1篇
预防医学   28篇
药学   17篇
肿瘤学   28篇
  2022年   7篇
  2021年   8篇
  2020年   2篇
  2019年   3篇
  2018年   3篇
  2017年   6篇
  2016年   3篇
  2015年   2篇
  2014年   8篇
  2013年   9篇
  2012年   11篇
  2011年   22篇
  2010年   11篇
  2009年   19篇
  2008年   9篇
  2007年   9篇
  2006年   5篇
  2005年   5篇
  2004年   7篇
  2003年   11篇
  2002年   7篇
  2001年   13篇
  1999年   3篇
  1998年   6篇
  1997年   8篇
  1996年   4篇
  1995年   3篇
  1994年   3篇
  1993年   2篇
  1992年   3篇
  1989年   4篇
  1988年   6篇
  1987年   2篇
  1986年   4篇
  1985年   2篇
  1984年   1篇
  1983年   1篇
  1982年   2篇
  1981年   1篇
  1980年   2篇
  1979年   1篇
  1977年   1篇
  1976年   3篇
  1975年   4篇
  1974年   2篇
  1973年   1篇
  1971年   1篇
  1969年   1篇
  1936年   1篇
  1935年   2篇
排序方式: 共有258条查询结果,搜索用时 15 毫秒
61.
Kirchhofer  D; Tschopp  TB; Steiner  B; Baumgartner  HR 《Blood》1995,86(10):3815-3822
Activated platelets provide assembly sites for coagulation enzyme complexes and in this way can mediate coagulation during hemostasis and thrombosis. In this study, we examined the procoagulant activity of platelets adhering directly to fibrillar collagen, a main thrombogenic constituent of subendothelium. For this purpose, we used a human ex- vivo thrombosis model in which collagen-coated coverslips were exposed to flowing nonanticoagulated blood (shear rate, 65/s) for 5.5 minutes, which led to the deposition of adherent platelets, platelet thrombi, and fibrin. To examine the procoagulant activity of adherent platelets only, a selective antagonist of the platelet GPIIb-IIIa complex, Ro 44- 9883, was infused via a mixing device, resulting in a complete abrogation of platelet thrombus formation but leaving the collagen- adherent platelet layer intact. This platelet layer generated increased postchamber fibrinopeptide A (FPA) levels (203 +/- 33 ng/mL) as compared with control experiments without infusion of inhibitor (95 +/- 13 ng/mL). Concomitantly, fibrin deposition measured by morphometric analysis of cross-sections was also increased, as was the platelet adhesion to collagen. An immunochemical staining of fibrin fibers further showed that the adherent platelets formed the nuclei for fibrin fiber formation. This increase in fibrin deposition was mediated by the intrinsic factor X (F.X) activation complex on adherent single platelets, because almost complete inhibition of FPA generation (9 ng/mL) and fibrin deposition (0.4% +/- 0.2% coverage) was achieved upon coinfusion of the GP IIb-IIIa antagonist and active site-inhibited F.IXa. The large platelet thrombi that were deposited in control experiments contained no significant amounts of immunodetectable fibrin except at the thrombus base, where adherent platelets anchored the thrombi to the collagen surface. These results suggest that the collagen-adherent platelets are important promoters of coagulation during the initial phase of thrombogenesis by providing assembly sites for the F.X activation complex.  相似文献   
62.
Objective:To investigate the effects of Dracaena arborea(D.arborea) on the sexual behavior parameters in experienced type-1 diabetic rats.Methods:Aqueous and ethanol(100 and 500mg/kg respectively)extracts of dried root barks of D.arborea.sildenafil citrate(1.44 mg/kg),trimethylamine-N-oxide(TMAO,20 mg/kg)and distilled water(110 mL/kg.were orally administered to 4 weeks streptozolocin-induced diabetic rats.Mount latency and frequency(ML.MF),intromission latency and frequency(IL,IF) and post-ejaculatory interval(PEI) were measured by ejaculating series during 90 min once a week for 4 weeks.Glycemia was determined at the beginning and at the end of the treatment Results:D.arborea did not show any major antihvperglycemic effects.Compared to the control group,a significant(P0.05-0.001)increase in MF and IF was noticed in rats treated with sildenafil citrate(89.71% and 90.07% respectively),aqueous(500 mg/kg.88.08%and 88.749;respectively) and ethanol(100 mg/kg;89.53%and 89.17respectively) extracts of D.arborea after two weeks(series 1) of treatment.ML,IL and PEI were significantly(P0.05-0.001) decreased after 4 weeks of daily treatment[sildenafil citrate(96.31.96.31%and 34.98%),and D.arborea aqueous 500 mg/kg(94.33.94.33% and 66.609;i and ethanol extracts 100 mg/kg(96.98.97.089;and 64.26%)].Conclusions:These aphrodisiac potentials of D.arborea in experienced diabetic rats could be due to the antioxidant and androgenic properties of phenols,flavonoids.saponins and sterols revealed in the plant extracts.  相似文献   
63.
Haddy  TB; Keenan  AM; Jaffe  ES; Magrath  IT 《Blood》1988,72(4):1141-1147
Of 95 young non-Hodgkin's lymphoma patients entered consecutively on the National Cancer Institute (NCI) Protocol 7704, 26 (27.4%) had involvement of one or more bones. The mean age of these 26 patients was 16.6 years, and the male to female ratio was 3.3:1. Tumor histology included undifferentiated Burkitt's lymphoma in 12, undifferentiated non-Burkitt's lymphoma in two, undifferentiated, unspecified lymphoma in one, diffuse large cell lymphoma in three, and lymphoblastic lymphoma in eight patients. Most had extensive disease; two patients had isolated bone lesions, one had lesions of two bones without involvement of other tissues, and 23 had either multiple bone lesions or single bone lesions with involvement of other tissues. Eight of the 26 patients had bone marrow involvement. Of a subgroup of 12 patients with jaw disease, 11 had undifferentiated lymphoma and one had diffuse large cell lymphoma. Only one had primary a jaw tumor, with two quadrants of the jaw involved. All 26 patients were treated with chemotherapy; only two received radiotherapy initially for bone lesions. Predicted survival of the 26 patients at 5 years is 53.2%. The 12 patients who remain disease free have a mean survival of 62.1 months (range, 22 to 100 months). Our results call into question the role of radiotherapy in the treatment of bone lesions in non-Hodgkin's lymphoma.  相似文献   
64.
65.
66.
67.
安徽省结核病结核杆菌耐药状况的调查   总被引:1,自引:1,他引:0  
目的为了解安徽省新发涂阳肺结核病人的耐药状况。方法随机选择安徽皖南、皖中和皖北的6个县结核病项目门诊,收集项目门诊的初治涂阳病人的结核杆菌;采用WHO/IUATLD推荐的比例法,对异烟肼(H)、链霉素(S)、利福平(R)、乙胺丁醇(E)等4种抗结核药敏试验。结果449株结核分枝杆菌中对4种抗结核药物全部敏感者248例,占55.23%;201例耐药,总原发耐药率为44.77%,以耐S为最高,占31.4%。结论安徽省结核病耐药水平是较严重省份,对结核病控制工作将是一个大的挑战,耐药结核杆菌的控制将是下一步结核病控制重点之一。  相似文献   
68.

Background  

Cow's milk is the most common food allergen in infants and the diagnosis of cow's milk allergy is difficult, even with the use of several diagnostic tests. Therefore, elimination diets and challenge tests are essential for the diagnosis and treatment of this disorder. The aim of this study is to report the clinical presentation and nutritional status of children evaluated by pediatric gastroenterologists for the assessment of symptoms suggestive of cow's milk allergy.  相似文献   
69.
70.
Objectives  To describe the tolerability of two chemotherapy regimens, gemcitabine and cisplatin (GC) and methotrexate, vinblastine, doxorubicin, and cisplatin (MVAC) for adjuvant treatment of patients with locally advanced urothelial cancer after radical cystectomy. Methods  The USC Department of Urology bladder cancer database was searched for subjects who received adjuvant chemotherapy following cystectomy for transitional cell carcinoma with extravesical and/or lymph node involvement, yielding 187 cases. Clinical details regarding toxicity, number of cycles administered, and cancer outcome were analyzed. Results  The majority of subjects had lymph node involvement (70%). Sixty-eight percent of subjects received MVAC and 32% received GC, the latter regimen was predominant after 2000. Fifty-six percent of subjects received all four planned cycles (51% GC and 58% MVAC). With a median follow-up of 11.2 years (range 1.9–19.6), 96 patients (51%) have suffered a relapse, with no significant difference between chemotherapy regimens. Median time to recurrence for the population was 3.7 years and median overall survival is 4.6 years (3.0–9.3). The median time from recurrence to death was 6.7 months and was not significantly different between MVAC and GC. Conclusions  Both MVAC and GC are tolerated after cystectomy for advanced urothelial carcinoma. A significant proportion of high-risk patients survive, free of disease, beyond 10 years. At recurrence, patients previously treated with adjuvant chemotherapy have a survival that appears much shorter than patients who develop metastases in the absence of this exposure, suggesting resistance to salvage chemotherapy.  相似文献   
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号