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   1513篇
  免费   94篇
  国内免费   21篇
耳鼻咽喉   14篇
儿科学   28篇
妇产科学   24篇
基础医学   218篇
口腔科学   51篇
临床医学   126篇
内科学   406篇
皮肤病学   8篇
神经病学   130篇
特种医学   31篇
外科学   225篇
综合类   3篇
预防医学   43篇
眼科学   4篇
药学   112篇
肿瘤学   205篇
  2024年   4篇
  2023年   32篇
  2022年   57篇
  2021年   88篇
  2020年   38篇
  2019年   64篇
  2018年   67篇
  2017年   38篇
  2016年   55篇
  2015年   52篇
  2014年   43篇
  2013年   61篇
  2012年   96篇
  2011年   110篇
  2010年   50篇
  2009年   33篇
  2008年   89篇
  2007年   90篇
  2006年   60篇
  2005年   70篇
  2004年   48篇
  2003年   47篇
  2002年   62篇
  2001年   19篇
  2000年   19篇
  1999年   22篇
  1998年   16篇
  1997年   7篇
  1996年   15篇
  1995年   12篇
  1994年   5篇
  1993年   7篇
  1992年   10篇
  1991年   10篇
  1990年   17篇
  1989年   7篇
  1988年   9篇
  1987年   9篇
  1986年   5篇
  1985年   8篇
  1984年   4篇
  1983年   4篇
  1981年   4篇
  1980年   5篇
  1977年   9篇
  1976年   4篇
  1972年   5篇
  1969年   10篇
  1968年   4篇
  1966年   7篇
排序方式: 共有1628条查询结果,搜索用时 0 毫秒
21.
Monocyte chemoattractant protein-1 (MCP-1) is a chemokine that is produced mainly by tubular epithelial cells in kidney and contributes to renal interstitial inflammation and fibrosis. More recently, we have demonstrated that urinary MCP-1 excretion is increased in proportion to the degree of albuminuria (proteinuria) and positively correlated with urinary N-acetylglucosaminidase (NAG) levels in type 2 diabetic patients. Based on these findings, we have suggested that heavy proteinuria, itself, probably aggravates renal tubular damage and accelerates the disease progression in diabetic nephropathy by increasing the MCP-1 expression in renal tubuli. In the present study, to evaluate whether urinary MCP-1 excretion is increased in the proteinuric states not only in diabetic nephropathy but also in other renal diseases, we examined urinary MCP-1 levels in IgA nephropathy patients with macroalbuminuria (IgAN group; n = 6), and compared the results with the data obtained from type 2 diabetic patients with overt diabetic nephropathy (DN group; n = 23) and those without diabetic nephropathy (non-DN group; n = 27). Urinary MCP-1 excretion levels in non-DN, DN, IgAN groups were 157.2 (52.8-378.5), 346.1 (147.0-1276.7), and 274.4 (162.2-994.5) ng/g creatinine, median (range), respectively. Expectedly, urinary MCP-1 and NAG excretion levels in DN and IgAN groups were significantly elevated as compared with non-DN group. Therefore, we suggest that MCP-1 expression in renal tubuli is enhanced in proteinuric states,irrespective of the types of renal disease, and that increased MCP-1 expression probably contributes to renal tubular damage in proteinuric states.  相似文献   
22.

Background

IgA nephropathy (IgAN) is a chronic glomerular disease that causes end-stage renal disease in 20–40 % of patients within 20 years. The efficacy of tonsillectomy combined with steroid pulse (SP) administration (TSP) for clinical remission of IgAN has been reported. Particularly in Japan, TSP has been performed widely. However, the optimum method for steroid administration in TSP has not been established.

Methods

We retrospectively compared clinical remission in IgAN patients treated with tonsillectomy combined with two different steroid administration methods: (1) three courses of SP therapy and oral prednisolone administered on alternate days (group 3A; n = 25); and (2) one course of SP therapy and oral prednisolone administered on consecutive days (group 1C; n = 22).

Results

There was no significant difference in the clinical remission rates between the two groups at 12 (48.0 vs. 40.9 %, P = 0.77) and 24 months after starting treatment (68.0 vs. 72.7 %, P = 0.76) and at the final observation (76.0 vs. 81.8 %, P = 0.73). The mean period from starting treatment to remission of hematuria in group 3A was significantly shorter than that in group 1C (5.7 ± 4.4 vs. 9.9 ± 5.9 months, P = 0.03). Dyslipidemic patients treated for the first time with statin after the SP therapy were more present in group 3A at 24 months (P = 0.02).

Conclusions

In IgAN patients, treatment of group 3A may be effective for inducing rapid remission of hematuria. Further studies are needed to establish an appropriate protocol for TSP.
  相似文献   
23.
Background The purpose of this study was to investigate the natural course of the minimally symptomatic nonoperated hip in patients with preosteoarthritis or early osteoarthritis in bilaterally dysplastic hips. Methods The material consisted of 61 patients with bilaterally dysplastic hips who underwent rotational acetabular osteotomy in their symptomatic hip and nonoperative treatment in their asymptomatic or minimally symptomatic hip. The average follow-up was 10.1 years (range 7.0–15.6 years), and the average age at the time of surgery was 38.2 years (range 20–58 years). All patients were divided into two groups by joint congruity of the nonoperated hip at surgery with rotational acetabular osteotomy. Results On radiographic assessment, 1 of the 35 preosteoarthritis hips had developed early osteoarthritis, and 6 of the 26 early osteoarthritis hips had progressed to advanced osteoarthritis. The Kaplan-Meier survivorship analysis for the whole group of nonoperated hips, with radiographic progression of osteoarthritis as the endpoint, predicted a 10-year survival rate of 83.7% (95% confidence interval 70%–98%). Significant differences were observed in the radiographic stage (pre- and early osteoarthritis group, P = 0.015) and joint congruity (good and fair group, P = 0.005). Conclusions If the contralateral nonoperated hip has good joint congruity, minimal symptoms, and no or little radiographic change in patients with pre- or early osteoarthritis and bilateral acetabular dysplasia, the probability of radiographic progression is low.  相似文献   
24.
Abstract:   A 61-year-old woman presented with chest pain. Chest CT revealed a mass of 6 cm diameter in the right lower lobe. Bronchoscopic biopsy showed squamous cell carcinoma. Video-assisted thoracotomy revealed that the main tumour was directly invading the liver through the diaphragm. To alleviate local symptoms and for possible cure with adjuvant chemotherapy and radiotherapy, standard right lower lobectomy and mediastinal dissection were carried out, followed by combined resection of the diaphragm and posterior superior segmentectomy of the liver. Eleven months postoperatively, the patient was alive but had a metastatic lesion in the other lobe of the liver which reduced in size following chemotherapy.  相似文献   
25.
BACKGROUND: In Japan, the inoculation dosage of inactivated influenza vaccine for children under 1 year old is 0.1 mL per dose. The dosage is not half as much as that in Europe and the U.S.A. We considered that low efficacy fate of influenza vaccine in children under 1 year old results from its less dosage. So we designed this study to verify this hypothesis. MATERIALS AND METHODS: This study was prospective in design. Subjects were divided into two groups by age: 8 to 11 months old (n = 26) and 12 to 16 months old (n = 22). Infants received 0.1 mL of inactivated influenza vaccine and over 1 year, 0.2 mL. Forty-eight children were inoculated twice at intervals of over 4 weeks. Serum samples were drawn before the first inoculation and 1 month after the second vaccination. Pre- and post-immunization antibody titers were measured. The titers of hemaglutinatinin inhibiting antibodies to the 3 viral strains were assayed. Antibody titers were determined using HAI. RESULTS: The post-vaccination proportions of children with protective HAI antibody titers were significantly smaller in infants than those in children over 1 year old (A/H1N1; 23% vs. 77%, A/H3N2; 39% vs. 73%, B; 0% vs. 32%). The number of children with >four-fold increased antibodies were significantly smaller in infants than that in 1 year old (A/H1N1; 74% vs. 91%, B; 0% vs. 39%). In the mean antibody titer, there were signficant differences between infants and children over 1 year old (A/H1N1; 19 times vs. 56 times, B; 8 times vs. 14 times). CONCLUSION: We consider that significant differences in antibody titers between infants and children over 1 year old were caused by the difference of dosage in influenza vaccines. To obtain protective levels of antibodies by influenza vaccines in infants, they must be inoculated with enough dosage.  相似文献   
26.
Esteroprotease, an androgen-dependent enzyme of the mouse submandibular gland, was increased by injection of tri-iodothyronine (T3) in mice with testicular feminization (Tfm) which are genetically deficient in androgen receptors. Histochemical and electron microscopic studies also demonstrated increases of RNA and serous-like granules in cells of the convoluted tubules of the gland. These findings suggest that the esteroprotease gene in Tfm mice is normal and that T3 can induced both esteroprotease and serous-like granules independently of androgen.  相似文献   
27.
28.
29.
30.
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