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   1653篇
  免费   87篇
  国内免费   4篇
耳鼻咽喉   8篇
儿科学   62篇
妇产科学   31篇
基础医学   117篇
口腔科学   8篇
临床医学   82篇
内科学   362篇
皮肤病学   89篇
神经病学   156篇
特种医学   77篇
外国民族医学   1篇
外科学   292篇
综合类   9篇
预防医学   82篇
眼科学   10篇
药学   78篇
中国医学   3篇
肿瘤学   277篇
  2023年   8篇
  2022年   19篇
  2021年   38篇
  2020年   16篇
  2019年   35篇
  2018年   28篇
  2017年   26篇
  2016年   29篇
  2015年   39篇
  2014年   43篇
  2013年   64篇
  2012年   94篇
  2011年   105篇
  2010年   61篇
  2009年   70篇
  2008年   68篇
  2007年   65篇
  2006年   66篇
  2005年   58篇
  2004年   54篇
  2003年   61篇
  2002年   60篇
  2001年   43篇
  2000年   49篇
  1999年   41篇
  1998年   26篇
  1997年   23篇
  1996年   32篇
  1995年   17篇
  1994年   26篇
  1993年   18篇
  1992年   31篇
  1991年   39篇
  1990年   33篇
  1989年   37篇
  1988年   30篇
  1987年   18篇
  1986年   21篇
  1985年   20篇
  1984年   15篇
  1983年   7篇
  1981年   7篇
  1979年   12篇
  1976年   9篇
  1975年   11篇
  1974年   9篇
  1973年   6篇
  1969年   9篇
  1968年   9篇
  1967年   7篇
排序方式: 共有1744条查询结果,搜索用时 15 毫秒
61.
OBJECTIVE: To assess outcome after a 2-stage hepatectomy procedure (TSHP) combined with portal vein embolization (PVE) in the treatment of patients with unresectable multiple and bilobar colorectal liver metastases (MBCLM). BACKGROUND: Patients with MBCLM are often considered for palliative chemotherapy only, due to too small future remnant liver (FRL). Recently, right hepatectomy with simultaneous left liver wedge resections after previous right PVE has been reported in a curative intent. However, the growth of metastatic nodules in FRL after PVE can be more rapid than that of the nontumoral remnant hepatic parenchyma. Therefore, metastases located in the FRL should be ideally resected before PVE. Then, a right (or extended right) hepatectomy can be safely performed during a second-stage hepatectomy. Therefore, we analyzed our experience with the use of TSHP combined with PVE in treatment of MBCLM. PATIENTS AND METHODS: Between December 1996 and April 2003, 33 patients with unresectable MBCLM were selected for a TSHP. A right or an extended right hepatectomy was planned after treatment of left FRL metastases to achieve a curative resection. The first-stage hepatectomy consisted in a clearance of the left hemiliver by resection or radiofrequency destruction of metastases of the left FRL. Subsequently, a right PVE was performed to induce atrophy of the right hemiliver and hypertrophy of the left hemiliver. Finally, a second-stage hepatectomy was planned to resect the right liver metastases. RESULTS: There was no operative mortality. Post-PVE morbidity was 18.1%; postoperative morbidity was 15.1% and 56.0% after first- and second-stage hepatectomy, respectively. TSHP could be achieved in 25 of 33 patients (75.7%). The 1- and 3-year survival rates were 70.0% and 54.4%, respectively, in the 25 patients in whom the TSHP was completed. CONCLUSIONS: In selected patients with initially unresectable MBCLM, a TSHP combined with PVE can be achieved safely with long-term survival similar to that observed in patients with initially resectable liver metastases.  相似文献   
62.
63.
The expression and function of a new cytokine-induced endothelial cell adhesion protein, vascular cell adhesion molecule-1 (VCAM-1), was characterized in vitro by using a monoclonal antibody, MoAb 4B9, which recognizes a functional epitope on this protein. As determined by enzyme-linked immunosorbent assay and radioimmunoprecipitation of metabolically labeled cells, VCAM-1 was minimally expressed on unstimulated human umbilical vein endothelium (HUVE), but was rapidly induced by recombinant human tumor necrosis factor-alpha (rhTNF-alpha), rh interleukin-1, and lipopolysaccharide. In contrast to intercellular adhesion molecule-1, VCAM-1 was not induced on dermal fibroblasts or arterial smooth muscle cells after stimulation with rhTNF, or on keratinocytes after stimulation with rh interferon-gamma. MoAb 4B9 significantly inhibited the adherence of peripheral blood lymphocytes (PBL) and lymphocytic cell lines, but not neutrophils, to rhTNF-activated HUVE. The inhibitory effect of MoAb 4B9 on PBL adherence to HUVE was additive to that produced by the CD18 MoAb 60.3. These results show that VCAM-1 mediates a CD18-independent pathway of peripheral blood lymphocyte adherence to cytokine-stimulated HUVE. We propose that lymphocyte binding to VCAM-1, induced on endothelium by cytokines, may be an important component of lymphocyte emigration at sites of inflammation or immune reaction.  相似文献   
64.
Tuberculosis (TB) mortality is high among kidney transplant (KT) recipients. Although local epidemiology is an important factor, diagnostic/therapeutic challenges and immunosuppressive therapy (ISS) may influence outcomes. We analyzed the cumulative incidence (CumI) of TB in KT recipients receiving a variety of ISS with long‐term follow‐up. Our retrospective single‐center cohort study included all KT procedures performed between January 1, 1998, and August 31, 2014, with follow‐up until August 31, 2014. Induction therapy was based on perceived immunological risk; maintenance ISS included prednisone and calcineurin inhibitor (CNI) plus azathioprine (AZA), and mycophenolic acid (MPA) or mechanistic target of rapamycin inhibitor (mTORi). Thirty‐four patients received belatacept/MPA. KT was performed on 11 453 patients and followed for 1989 (IQR 932 to 3632) days. Among these, 152 patients were diagnosed with TB (CumI 1.32%). Median time from KT to TB was 18.8 (IQR 7.2 to 60) months, with 59% of patients diagnosed after the first year. Unadjusted analysis revealed an increasing confidence interval (CI) of TB (0.94% CNI/AZA vs 1.6% CNI/MPA [HR = 1.62, 95% CI = 1.13 to 2.34, P = .009] vs 2.85% CNI/mTORi [HR = 2.45, 95% CI = 1.49 to 4.32, P < .001] vs 14.7% belatacept/MPA [HR = 13.14, 95% CI = 5.27 to 32.79, P < .001]). Thirty‐seven (24%) patients died, and 39 (25.6%) patients experienced graft loss. Cytomegalovirus infection (P = .02) and definitive ISS discontinuation (P < .001) were associated with death. Rejection (P = .018) and ISS discontinuation (P = .005) occurred with graft loss. TB occurred at any time after KT and was influenced by ISS.  相似文献   
65.
66.
Acne vulgaris is a common dermatological disorder that predominantly affects teenagers, but can also affect preadolescents and post-teen individuals. Despite the fact that acne vulgaris is the most common skin disorder encountered in ambulatory dermatology practice in the United States, there has been limited research on the epidermal permeability barrier in untreated skin of people with acne vulgaris and also after use of acne therapies. This article reviews the research results and discusses the available literature on this subject area. The importance of proper skin care as a component of the management of acne vulgaris is supported by the information that is currently available.  相似文献   
67.
68.
Endocervical metastases secondary to breast carcinoma. A case report   总被引:1,自引:0,他引:1  
Only 24 cases of breast cancer metastases to the uterine cervix have been reported to date. The present case present secondary cervical involvement in the absence of concomitant extragenital metastases. The patient did not present with abnormal vaginal discharge and the cervical lesion responded to conventional combination chemotherapy for breast cancer.  相似文献   
69.
Between August 1983 and December 1986, 116 previously untreated patients with squamous cell carcinoma of the head and neck were randomized to receive induction chemotherapy followed by radiotherapy given in conventional fractions (55 patients, arm A) or an alternating chemotherapy and radiotherapy (3 courses of 20 Gy, 10 daily fractions each; 61 patients, arm B). The same chemotherapy was used in both arms: 6 mg/m2 vinblastine sulfate, hour 0; 30 mg bleomycin, hour 6; 200 mg methotrexate, hours 24 to 26; 45 mg leucovorin, hour 48. Forty-five patients had stage III disease and 71 had stage IV disease. All patients were evaluated for survival, 112 for toxicity, and 105 for analyses of response and time from the start of treatment until progression of disease. At the end of the combined treatment, we observed an overall response rate of 52% in arm A and an overall response rate of 64.9% in arm B. The incidence of mucositis was more relevant in arm B compared to arm A (P less than .00004). The difference in complete response, progression-free survival, and survival was statistically significant, with an advantage for arm B (P less than .03, P less than .02, and P less than .03, respectively). The analysis at a median follow-up of 36 months (range = 19 to 59) demonstrates a higher effectiveness for the alternating program.  相似文献   
70.
Histochemical and immunohistochemical studies performed in only a few cases of sinus histiocytosis with massive lymphoadenopathy (SHML) indicated that SHML cells belong to themacrophage — histiocyte system, though their exact origin is still uncertain. We analyzed the morphological, antigenic and enzymatic characteristics of the histiocyte-like cells in one paediatric case of SHML (also named Rosai-Dorfman disease). The SHML cells expressed the S-100 protein, lectins concanavalin A, peanut agglutinin andmonocyte-macrophage related antigens CD 11c, CD 14, CD 33, CD 68 and LN 5. Reactivity with other anti-macrophage antibodies (MAC 387, lysozyme, alpha-1 anti-chymotrypsin) was variable. The CD1a antigen was present only in scattered cells, whereas HLA-DR and the HLA-DR associated invariant chain were absent. Cytochemistry demonstrated an intense activity of acid phosphatase and non specific esterase of SHML cells. A large amount of medium sized mononuclear cells were located in the sinuses and intersinusoidal tissue. Our findings suggest that SHML cells have intermediate features between phagocytes and Langerhans cells/interdigitating reticulum cells. The heterogeneity of marker expression on SHML cells might be related to the local content of factors (e.g., cytokines), capable of modulating the phenotype of monocyted and derived cells.  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