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   1334篇
  免费   44篇
  国内免费   17篇
耳鼻咽喉   15篇
儿科学   8篇
妇产科学   4篇
基础医学   138篇
口腔科学   15篇
临床医学   142篇
内科学   445篇
神经病学   88篇
特种医学   29篇
外科学   201篇
综合类   5篇
预防医学   70篇
眼科学   10篇
药学   86篇
中国医学   3篇
肿瘤学   136篇
  2023年   13篇
  2022年   37篇
  2021年   47篇
  2020年   36篇
  2019年   35篇
  2018年   42篇
  2017年   24篇
  2016年   31篇
  2015年   22篇
  2014年   43篇
  2013年   39篇
  2012年   86篇
  2011年   78篇
  2010年   62篇
  2009年   32篇
  2008年   63篇
  2007年   68篇
  2006年   74篇
  2005年   64篇
  2004年   76篇
  2003年   56篇
  2002年   55篇
  2001年   35篇
  2000年   28篇
  1999年   16篇
  1998年   20篇
  1997年   11篇
  1996年   9篇
  1995年   8篇
  1994年   7篇
  1993年   6篇
  1992年   17篇
  1991年   16篇
  1990年   16篇
  1989年   12篇
  1988年   9篇
  1987年   9篇
  1986年   8篇
  1985年   6篇
  1984年   4篇
  1979年   7篇
  1978年   7篇
  1977年   5篇
  1973年   4篇
  1972年   5篇
  1971年   8篇
  1970年   8篇
  1969年   7篇
  1968年   6篇
  1967年   4篇
排序方式: 共有1395条查询结果,搜索用时 15 毫秒
1.
Aliskiren is a novel orally active renin inhibitor for the treatment of hypertension. This study evaluated the antihypertensive efficacy, safety and tolerability of aliskiren in Japanese patients with hypertension. Forty hundred and fifty-five Japanese men and women with a mean sitting diastolic blood pressure of 95-110 mmHg were randomized to receive once-daily double-blind treatment for 8 weeks with aliskiren 75, 150 or 300 mg or placebo. Aliskiren produced significant, dose-dependent reductions in mean sitting diastolic blood pressure (p<0.0005 vs. placebo for each dose) and mean sitting systolic blood pressure (p<0.001 vs. placebo for each dose). The placebo-corrected reductions in mean sitting systolic/diastolic blood pressure were 5.7/4.0, 5.9/4.5 and 11.2/7.5 mmHg in the aliskiren 75, 150 and 300 mg groups, respectively. After 8 weeks' treatment, 27.8%, 47.8%, 48.2% and 63.7% of patients in the placebo and aliskiren 75, 150 and 300 mg groups, respectively, achieved a successful treatment response (diastolic blood pressure <90 mmHg and/or reduced by > or =10 mmHg from baseline; p<0.005 vs. placebo for each dose). Aliskiren treatment was well tolerated, with the incidence of adverse events reported in the active treatment groups (53-55%) being similar to that in the placebo group (50%). This study, which is the first to assess the antihypertensive efficacy and safety of aliskiren in Japanese patients with hypertension, demonstrates that the once-daily oral renin inhibitor aliskiren provides significant, dose-dependent reductions in blood pressure with placebo-like tolerability.  相似文献   
2.
Hyperlipidemia, hypertension, and diabetes mellitus (DM) are well-established risk factors for cardiovascular disease. We analyzed the cardiovascular events in hyperlipidemic patients with or without DM who were administered open-labeled simvastatin in groups stratified by blood pressure level using data from the Japan Lipid Intervention Trial (J-LIT). Hyperlipidemic patients with DM (n=6,288) had significantly more cardiovascular events than those without DM (n=33,933). The incidence rates of total cardiovascular events in the Non-DM and DM groups were 15.40 and 25.76 per 1,000 patients for the 6-year period, respectively. The relative risk of total cardiovascular events in the DM vs. the Non-DM group was 1.68, and the relative risk was significantly higher in the DM than in the Non-DM group. The relative risks of total cardiovascular events were significantly higher in DM and Non-DM patients whose systolic blood pressure (SBP) was greater than or equal to 130 mmHg compared to that of Non-DM patients whose SBP was less than 130 mmHg, and in DM and Non-DM patients whose diastolic blood pressure (DBP) was greater than or equal to 80 mmHg compared to that of Non-DM patients whose DBP was less than 80 mmHg. In all groups stratified by SBP and DBP, relative risks of total cardiovascular events were higher in DM patients than in Non-DM patients. For patients with hypercholesterolemia and DM, blood pressure should be strictly controlled in order to prevent both coronary events and stroke. These results are in good agreement with the JNC 7 and the ESH/ESC guidelines for DM patients, which recommended that the SBP and DBP be less than 130 and 80 mmHg, respectively.  相似文献   
3.
The effect of ethylene glycol on rat hepatic microsomal cytochrome P-450 was studied in vitro and in vivo. The destruction of cytochrome P-450 was not seen in vitro. The addition of 1 mM NADPH also did not change. When ethylene glycol was added to drinking water at a concentration of 1.0% for 7 days, there was no change in the contents of microsomal protein, cytochrome P-450, b5 and heme. While NADPH-cytochrome C reductase activity of the exposed group did not change, NADH-ferricyanide reductase activity increased significantly.  相似文献   
4.
Endoscopic resection has been accepted as the standard treatment for intramucosal gastric tumors of differentiated type. However, the indication was limited to small tumors to achieve en bloc resection and prevent local recurrence in cases of conventional endoscopic mucosal resection (EMR) such as the strip biopsy and the cap technique. To avoid multi‐fragmental resection, we have developed endoscopic submucosal dissection (ESD) as a new endoscopic resection technique. ESD is a remarkable technique, because we make it possible to remove the lesions en bloc regardless of size, shape, coexisting ulcer, and location. However, it is difficult or impossible to resect recurrent tumors en bloc in conventional EMR owing to hard fibrosis, and some patients need laparotomy. Using ESD, we can dissect the submucosal layer as we directly look at the submucosa, and remove the lesion safely and reliably even in cases of hard fibrosis. The key to treatment of recurrent tumors in ESD are as follows: (i) using enough submucosal injection solution (we use a mixture of Glyceol and 1% 1900 kDa hyaluronic acid preparation); (ii) incising the mucosa without fibrosis; (iii) understanding characteristics of various cutting devices, and changing other devices in difficult situations. In these ways we can remove the majority of the recurrent tumors en bloc. Hence, we consider that ESD is a very effective treatment which achieves excellent en bloc and complete resection rates and enables patients with intramucosal gastric tumors to a recurrent‐free survival even in recurrent tumors.  相似文献   
5.
Optical technological innovations enable us to visualize cellular nuclei endoscopically. Herein is described a protocol design for a multicenter study for the ex vivo evaluation of endocytoscopy. The present study was performed by the Endoscopy Forum Japan study group.  相似文献   
6.
A 60-year-old Japanese man was hospitalized because of urinary leakage from the anus on October 3, 1994. Retrograde urethrography detected a fistula between the bulbous urethra and the rectum. Urethrocystoscopy revealed a tumor on the urethrorectal fistula. Tumor biopsy showed a well differentiated adenocarcinoma. Cystourethrectomy with fistulectomy, and ileal conduit urinary diversion were performed. Pathological examination revealed primary adenocarcinoma in the fistula with invasion to the prostatic urethra and bladder wall. The patient showed no evidence of a recurrence as of August, 1996.  相似文献   
7.
Protodioscin (PD) was purified from fenugreek (Trigonella foenumgraecum L.) and identified by Mass, and 1H- and 13C-NMR. The effects of PD on cell viability in human leukemia HL-60 and human stomach cancer KATO III cells were investigated. PD displayed strong growth inhibitory effect against HL-60 cells, but weak growth inhibitory effect on KATO III cells. Morphological change showing apoptotic bodies was observed in the HL-60 cells treated with PD, but not in KATO III cells treated with PD. Flow cytometric analysis showed that the hypodiploid nuclei of HL-60 cells were increased to 75.2, 96.3, and 100% after a 3-day treatment with 2.5, 5, and 10 microM PD, respectively. The fragmentation by PD of DNA to oligonucleosomal-sized fragments, that is a characteristic of apoptosis, was observed to be both concentration- and time-dependent in the HL-60 cells. These findings suggest that growth inhibition by PD of HL-60 cells results from the induction of apoptosis by this compound in HL-60 cells.  相似文献   
8.
There is disagreement among researchers concerning whether glutamatergic N-methyl-D-aspartate (NMDA) receptors play a role in constructing spatial representations. Therefore, the authors reexamined the effects of the NMDA antagonist on a spatial discrimination task using rats in a water pool. The authors confirmed that MK-801 impaired acquisition of the spatial discrimination task (Experiment 1). When rats were pretrained before drug treatment, MK-801 induced learning deficits in the novel environment but not in the familiar environment (Experiment 2). Moreover, in a familiar environment, MK-801 did not impair spatial learning, even when the task was completely novel for the rats (Experiment 3). These results suggest that NMDA receptors play an important role in the construction of spatial representations but not in the use of them.  相似文献   
9.
Human T-cell leukemia virus type I (HTLV-I) transmission during blood transfusion can be prevented by screening for and eliminating blood containing anti-HTLV-I antibodies. For this purpose, we evaluated two commercial test kits for HTLV-I antibodies, Serodia-ATLA (particle agglutination assay [PA]) and Eitest-ATL (enzyme-linked immunosorbent assay [ELISA]), by using serum samples from Japanese blood donors. Of 2,316 serum samples, 39 (1.7%), 34 (1.5%), and 28 (1.2%) were positive for the antibody by PA, ELISA, and immunofluorescence (IF), respectively. The coincidence rate for antibody-positive and antibody-negative results was 99.5% between PA and IF, whereas it was 99.6% between ELISA and IF. The serum samples which were positive by IF were also positive by PA, whereas 2 of 26 IF-positive samples were negative by ELISA. All the samples positive by both PA and ELISA were shown to be positive by IF unequivocally. The samples positive by only one of the two methods (PA or ELISA) were different. Eleven and eight serum samples that were negative by IF but positive by PA and ELISA, respectively, were further studied for HTLV-I antibody by radioimmunoprecipitation. Three of the former but none of the latter were found to be positive for antibody. Moreover, a PA-positive but IF-negative serum sample was shown to have significantly decreased PA titers after 2-mercaptoethanol treatment. The PA was further shown to detect not only IgG antibody but also IgM antibody to HTLV-I after separation of this serum sample by high-performance liquid chromatography.  相似文献   
10.
The efficacy, safety, and pharmacokinetics of bisoprolol were investigated following oral administration once daily for 12 weeks in hyperreninemic patients with dialysis-refractory hypertension. Mean blood pressure rapidly fell from 132 to 112 mmHg in the 5.0-mg/day (n = 6) and from 142 to 128 mmHg in the 2.5-mg/day patients (n = 5), which were accompanied by a fall in plasma renin activity. On nondialysis days, Cmax and T1/2 were significantly higher in patients than in healthy control subjects. However, Cmax in the 2.5-mg/day patients was almost equal to that in healthy control subjects receiving 5.0 mg/day of bisoprolol. Plasma bisoprolol was dialyzable. During the course of the study, dialysis hypotension and bradycardia occurred in two patients receiving 5.0 mg/day of bisoprolol. In conclusion, a daily dose of 2.5 mg bisoprolol seems to be an adequate and relatively effective dose in our patients with dialysis-refractory hypertension.  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