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   2175篇
  免费   117篇
  国内免费   10篇
耳鼻咽喉   10篇
儿科学   72篇
妇产科学   8篇
基础医学   315篇
口腔科学   18篇
临床医学   108篇
内科学   535篇
皮肤病学   24篇
神经病学   215篇
特种医学   111篇
外科学   472篇
综合类   9篇
预防医学   51篇
眼科学   42篇
药学   71篇
中国医学   1篇
肿瘤学   240篇
  2023年   14篇
  2022年   34篇
  2021年   56篇
  2020年   32篇
  2019年   45篇
  2018年   59篇
  2017年   38篇
  2016年   47篇
  2015年   45篇
  2014年   67篇
  2013年   86篇
  2012年   95篇
  2011年   114篇
  2010年   94篇
  2009年   79篇
  2008年   130篇
  2007年   122篇
  2006年   144篇
  2005年   148篇
  2004年   143篇
  2003年   132篇
  2002年   137篇
  2001年   43篇
  2000年   29篇
  1999年   41篇
  1998年   39篇
  1997年   28篇
  1996年   18篇
  1995年   20篇
  1994年   19篇
  1993年   13篇
  1992年   22篇
  1991年   19篇
  1990年   19篇
  1989年   10篇
  1988年   9篇
  1987年   11篇
  1986年   6篇
  1985年   11篇
  1984年   4篇
  1983年   8篇
  1982年   8篇
  1981年   8篇
  1980年   5篇
  1978年   6篇
  1976年   4篇
  1974年   3篇
  1972年   8篇
  1970年   4篇
  1967年   3篇
排序方式: 共有2302条查询结果,搜索用时 15 毫秒
91.
Cellular adhesion of sialyl-Lewis-a(SLea)-positive pancreas carcinoma to endothelial cells (EC) is augmented by activation of EC via up-regulated E-selectin expression on EC. Co-cultivation of pancreas-carcinoma cells, PCI-24, with human umbilical-vein endothelial cells (HUVEC) for 5 hr at the PCI-to-HUVEC ratio of 1:10 induced E-selectin expression on the endothelial-cell surface, augmenting SLea-positive pancreas-carcinoma cell attachment with HUVEC. Culture supernatants of 6 tested pancreas-carcinoma cell lines contained soluble, E-selectin-inducing factor(s). The E-selectin-inducing effect by the supernatants was blocked by the protein-kinase-C inhibitor, H7. Antibodies against SLea and E-selectin but not SLex or ICAM-I blocked the increased pancreas-carcinoma-to-endothelial attachment. Paraformaldehyde(PFA)-fixed PCI-24 cells also induced E-selectin on vascular endothelial cells upon direct contact with endothelial cells, indicating the presence of a membrane-bound form. The 6 pancreas-carcinoma lines all produced IL-1α mRNA and protein but not IL-1β or TNF-α protein and/or mRNA Absorption of IL-lα from the supernatants by IL-lα-specific antibody almost completely abolished E-selectin-inducing activity. Anti-IL-lα antibody also abolished the E-selectin-inducing activity of PFA-fixed PCI. IL-1α production by PCI cells was up-regulated by TNF-α. These observations suggest that substance(s) produced by pancreas-carcinoma cells, in this case, IL-1α, may contribute to pancreas-carcinoma-cell colonization in non-inflamed, distant locations in vivo, by activating vascular endothelial cells.  相似文献   
92.
93.
Histologically proven eosinophilic myelitis has rarely been reported except in connection with parasitism. To clarify its clinicopathological features, we conducted a nationwide survey of biopsy-proven eosinophilic myelitis of unknown cause throughout Japan. Six such cases were collected and studied immunologically and pathologically. All were young to middle-aged men. All showed a protracted and fluctuating course with mild disability for 3-25 (mean 12.5) months before biopsy. Magnetic resonance imaging revealed localized lesions of T2-high and T1-iso signal intensity with a partial gadolinium enhancement in all cases. Cerebrospinal fluid (CSF) examinations were completely normal except for modest pleocytosis in two cases. Eosinophilia was present in the peripheral blood in two cases but was absent from the CSF of all cases. In spite of the chronic nature of the disease, spinal cord pathology revealed very active lesions with marked cell infiltration consisting mainly of CD8(+) T cells and varying numbers of eosinophils in the perivascular areas and the parenchyma. Both the myelin and axons were severely disrupted in all cases. Moreover, eosinophil cationic protein (ECP), an activated eosinophil product, was heavily deposited in the tissues. All but one case had hyperIgEemia and mite antigen-specific IgE in the sera, and two had accompanying atopic disorders. The present study thus revealed idiopathic eosinophilic myelitis to be a localized and persistent inflammation of the spinal cord, with distinct clinicopathological features, that has a possible link to atopic diathesis.  相似文献   
94.
We present a case of encrusted cystitis with ammonium acid urate calculi. An 88-year-old man was referred to our hospital to determine the cause of hematopyuria. He was a patient at another hospital for treatment of interstitial pneumonia with predonisolone. After admission to our hospital, kidney, ureter, bladder X-ray, computed togography and cystoscopy revealed calcification of about two-thirds of the mucosa of the bladder, and biopsy of the bladder revealed bacterial colonies with inflammation and calcification. Calculographic analysis revealed ammonium acid urate calculi. After treatment with antibiotics and irrigation with solita T1, an acidic solution of pH 3.5-6.5, inflammation and calcification were significantly reduced.  相似文献   
95.
A cross-sectional questionnaire study was carried out on nursery school (NS) teachers in public nursery schools in N city in Japan to determine the magnitude of associations of probable risk factors with neck, shoulder, and arm pain, adjusting for potential confounders in logistic regression models. Of 1438 subjects, responded to the questionnaire, 959 NS teachers in charge of a separate or mixed group of children were subjected to analyses. Prevalence of neck and/or shoulder pain was 33.6%-35.4% in NS teachers in charge of children aged 0, 0-1, 4, and 5 in contrast to 25.0-29.8% in those in charge of children aged 1,2, and 3. The prevalence of neck/shoulder pain tended to increase with the length of employment in all groups classified according to the age of children under care. In a logistic regression model that simultaneously adjusted demographic and personal variables, length of employment and care for children aged 0 in the workplace were found significantly associated with musculoskeletal pain. In further logistic models, pain in the neck/shoulders and arms had associations with some specific variables: care for children aged 0, holding/lifting a child/material, overwork, and poorly supported job situations. The odds ratios for those variables varied from 1.37 to 2.41. This results suggest that pain in the neck/shoulders and arms is induced by a wide variety of risk factors in NS teachers that include high physical workload, long working hours, job demand-support imbalance, and cumulative influence of workloads.  相似文献   
96.
Improving an unhealthy lifestyle decreases risk of incidence and death of lifestyle-related diseases. Consultation about a healthy lifestyle to recipients of health checkups conducted by public health nurses is one method for such improvement. The objective in the present study was to investigate the difference between consciousness of intervention by (1) the public health nurses who conducted consultations with recipients of health checkups and (2) the recipients who were consulted by the public health nurses. Data on 1,370 male white collar workers who underwent health checks were analyzed. When public health nurses determined that recipients required health consultation regarding lifestyle from the health checkup, they consulted with the recipients regarding improvement of lifestyle. The consultation regarding lifestyle included abstinence from smoking, drinking in moderation, exercise, and eating. The results of the analysis regarding difference in consciousness of the intervention by the public health nurses and the recipients show that (1) most drinkers did not think they were being discouraged to drink despite intervention by the public health nurses and (2) the smokers and the subjects with no habitual physical exercise tend to think that they were being consulted even though the public health nurses did not intervene regarding smoking and exercise.  相似文献   
97.
We treated a lower rectal carcinoma patient with preoperative radiation and chemotherapy, resulting in a downstaging, and the findings are reported herein. The patient is a 55-year-old woman endoscopically diagnosed with advanced rectal carcinoma at a site 3 cm from the dental line. Preoperative radiation and chemotherapy included whole pelvis irradiation (44 Gy in total) and 800 mg/day of 5'-DFUR administered until one day before the operation. On the 20th day after completing irradiation, a low anterior resection of the rectum was conducted. During the operation, we found serositis of the small intestine and retroperitoneal fibrosis thought to be due to the irradiation. Histopathologic findings showed: invasion degree, sm2; stage I with N0; and histologic grading, Grade 2. The patient started drinking water from postoperative day 1, and was discharged on postoperative day 11. At present, in Europe and the USA, large scale studies are being conducted to evaluate preoperative radiation and chemotherapy in patients with lower rectal carcinoma. We think that this therapy is an effective treatment, since a distance (AW) from the lower margin of the tumor and the cut edge of the anal end can be established.  相似文献   
98.
The efficacy and safety of preoperative chemotherapy with carmofur (HCFU) for colorectal cancer were evaluated in a randomized controlled study involving 63 institutes in the Kanto area. Patients aged 75 or younger with Dukes' B or C colorectal cancer were eligible if curative surgery was expected. In the end, 326 were eligible from 405 consecutive colorectal cancer patients. Patients in both the control (n = 162) and the new treatment group (n = 164) were given intravenous mitomycin C (MMC) 6 mg/m2 on day 0 and 7 after surgery and HCFU 300 mg/day orally from day 14 for a year. Patients in the new treatment group were also given oral HCFU for 14 days or more prior to surgery. All 326 patients were followed for 5 years or longer. Five-year overall and disease-free survival rates were not significantly different between the two groups (75.4% and 71.6% for the control, and 71.8% and 71.5% for the study group, respectively). In the subset analysis, neither cancer site nor nodal status affected the differences in overall- and disease-free survival rates between the groups. The present findings show no additional efficacy of preoperative chemotherapy with HCFU in survival from advanced colorectal cancer. Further investigations in terms of patient selection, treatment regimen, combined use of radiotherapy, and other factors would be required to determine the significance of preoperative chemotherapy against advanced colorectal cancer.  相似文献   
99.
100.
Spontaneous regression of diffuse B-cell type lymphoma of the lumbar vertebra is reported. A 61-year-old woman experienced spontaneous disappearance of a large psoas mass associated with an infiltrating process of the lumbar vertebrae. The biopsy of the residual change after spontaneous regression revealed reactive foamy histiocytes and small lymphocytes with no atypia. The lesion recurred 7 months later with no systemic treatment in the interim, when the diagnosis of lymphoma was finally made. Spontaneous regression may be related to potentiation of the host immune response, which affects tumor growth.  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