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   1276420篇
  免费   97675篇
  国内免费   1599篇
耳鼻咽喉   16463篇
儿科学   41553篇
妇产科学   35435篇
基础医学   191329篇
口腔科学   34914篇
临床医学   119743篇
内科学   250048篇
皮肤病学   27514篇
神经病学   103598篇
特种医学   47040篇
外国民族医学   265篇
外科学   179951篇
综合类   25893篇
现状与发展   4篇
一般理论   588篇
预防医学   106771篇
眼科学   28163篇
药学   93508篇
  7篇
中国医学   2031篇
肿瘤学   70876篇
  2019年   10535篇
  2018年   14159篇
  2017年   10856篇
  2016年   11845篇
  2015年   13586篇
  2014年   18607篇
  2013年   28495篇
  2012年   38931篇
  2011年   41331篇
  2010年   23750篇
  2009年   22859篇
  2008年   38688篇
  2007年   41392篇
  2006年   40835篇
  2005年   39884篇
  2004年   38298篇
  2003年   36597篇
  2002年   35482篇
  2001年   56110篇
  2000年   57102篇
  1999年   48176篇
  1998年   13503篇
  1997年   12308篇
  1996年   12703篇
  1995年   11975篇
  1994年   11152篇
  1993年   10441篇
  1992年   38235篇
  1991年   37693篇
  1990年   36462篇
  1989年   35285篇
  1988年   32714篇
  1987年   32054篇
  1986年   30551篇
  1985年   28801篇
  1984年   21976篇
  1983年   19204篇
  1982年   11399篇
  1979年   20956篇
  1978年   15405篇
  1977年   12795篇
  1976年   11856篇
  1975年   12829篇
  1974年   15591篇
  1973年   15366篇
  1972年   14513篇
  1971年   13554篇
  1970年   12789篇
  1969年   12066篇
  1968年   11230篇
排序方式: 共有10000条查询结果,搜索用时 234 毫秒
921.
Study DesignSystematic review.IntroductionContrast baths are used as an intervention in hand therapy, yet it is unclear which patients, if any, benefit from this intervention.Purpose of the StudyTo examine the nature and quality of the evidence regarding the use of contrast baths using a systematic review process.MethodsOf a total of 28 clinical research articles on contrast baths, from 1938 forward, ten met the inclusion criteria set by the authors.ResultsThese studies addressed the physiological changes of hot and cold on blood flow, intramuscular temperature, subcutaneous temperature, and the influence of room temperature and age. The subjects included normal/healthy volunteers and patients with a diagnosis of rheumatoid arthritis, diabetes, or foot/ankle injuries. The diversity of conditions, protocols, and outcomes limited the ability to make definitive conclusions on efficacy.ConclusionsThe contrast bath procedure may increase superficial blood flow and skin temperature, though the evidence on the impact on edema is conflicting. No relationship between physiologic effects and functional outcomes has been established.Level of Evidence: 2A  相似文献   
922.
AimsLocal coronary and systemic inflammation is pronounced in patients with diabetes mellitus (DM). Intracoronary thermography detects local inflammation and C-reactive protein (CRP) is a marker of systemic inflammation. We investigated whether or not, in patients with DM, thermal heterogeneity of culprit lesions (CLs) correlates with that of non-culprit lesions (NCLs) and with systemic inflammation.MethodsWe included DM patients who had two angiographically significant lesions and were undergoing percutaneous coronary intervention. We measured the temperature difference (ΔT) between the lesion and proximal vessel wall.ResultsWe included 104 (n = 208 lesions) patients: 32 (n = 64 lesions) had DM and 72 (n = 144 lesions) were non-DM (control group). ΔT was increased in DM in both CLs and NCLs (CLs: DM = 0.12 ± 0.06 °C; no DM = 0.06 ± 0.04 °C; P < 0.01 versus NCLs: DM = 0.13 ± 0.08 °C versus no DM = 0.06 ± 0.05 °C; P < 0.01). Patients with DM had similar ΔT in CLs and NCLs (P = 0.49). A linear correlation was detected between heat production in all lesions and CRP (R = 0.45; P < 0.01), which was attributed to the correlation of ΔT in lesions of patients with DM and CRP (R = 0.32; P < 0.01). In lesions of patients with low CRP, a greater rate of discrepancy was found, as 100% of lesions in patients with DM versus 66.1% of lesions of patients without DM had a high ΔT in one or both lesions (P < 0.01).ConclusionIn patients with DM, local inflammatory activation is diffuse and correlates with systemic inflammation. However, low systemic inflammatory activation does not always predict an increase in local thermal heterogeneity.  相似文献   
923.
924.
Renal transplantation has provided women of childbearing age with increased fertility and the possibility of successful pregnancy outcomes. Approximately 14,000 births among women with transplanted organs have been reported worldwide, but pregnancy complications have been frequent: spontaneous or therapeutic abortion, preterm birth, low birth weight, and intrauterine growth restriction. Herein we have described a case of an acute rejection episode in a renal transplant recipient, occurring 6 months after successful delivery, despite the fulfillment of all European best practice guidelines criteria and the maintenance of adequate immunosuppression. Our case demonstrated that even a presumably low-risk patient can face worsening of renal function during or after pregnancy. Acute immune activation is uncommon but may occur in late-onset fashion. Despite adequate levels of maintenance immunosuppression, there is a risk of developing antibodies against the partner or the donor, causing acute renal immune damage.  相似文献   
925.
When studying histological characteristics of human and porcine pancreata in relation to islet isolation, we encountered a remarkably high number of hyperemic islets. The abnormalities observed in these islets ranged from a single dilated vessel through multiple widely dilated vessels to hemorrhages extending into the surrounding exocrine tissue. We determined their possible relevance for outcomes of islet isolation. This study involved a histological examination of 143 porcine pancreata (72 juvenile and 71 adult) and islet isolation from 48 adult pancreata. Human pancreata obtained from 71 multiple organ donors yielded islet isolation in 24 cases. To determine their endocrine content, tissue samples were stained with Aldehyde Fuchsin. The presence of hyperemic islets was scored semiquantitatively with pancreata allotted to categories based on the severity. In humans and pigs we observed hyperemic islets in 48% of pancreata, but only 4.0 ± 2.4% of the islets were hyperemic. In both humans and pigs, significantly higher endocrine content was found in the most severely affected pancreata. When the higher endocrine content was taken into account and isolation results were expressed as ratios of yield and content, we observed significantly lower yields in the most affected pancreata in pigs with a trend toward lower yields in humans. A substantial proportion of human and porcine pancreata contain hyperemic islets. Although the results in humans are preliminary, our data suggest that this phenomenon may contribute to the unpredictable, highly variable islet yields in pigs and humans.  相似文献   
926.
927.
Aims: To explore the quality of life in patients treated medically during the acute phase of pancreatitis as well as at 2 and 12 months after discharge from the hospital. Patients: 40 patients were studied. The etiology of the pancreatitis was biliary causes in 31 patients and non-biliary causes in 9; mild disease was present in 29 patients and severe disease in 11. 30 patients completed the two surveys at 2 and 12 months after hospital discharge. Methods: The SF-12 and EORTC QLQ-C30 questionnaires were used for the purpose of the study. Results: The two physical and mental component summaries of SF-12, all the domains of EORTC QLQ-C30 (except for physical functioning and cognitive functioning) and some symptom scales of EORTC QLQ-C30 (fatigue, nausea/ vomiting, pain, and constipation) were significantly impaired during the acute phase of pancreatitis. There was a significant improvement in the SF-12 physical component summary, and global health, role functioning, social functioning, nausea/vomiting, pain, dyspnea, and financial difficulties (EORTC QLQ-C30) at 2 months after discharge as compared to the basal evaluation. Similar results were found after 12 months except for the mental component score at 12-month evaluation, which was significantly impaired in acute pancreatitis patients in comparison to the norms. The physical functioning of the EORTC QLQ-C30 at basal evaluation was significantly impaired in patients with severe pancreatitis in comparison to patients with mild pancreatitis. Conclusions: Two different patterns can be recognized in the quality of life of patients with acute pancreatitis: physical impairment is immediately present followed by mental impairment which appears progressively in the follow-up period.  相似文献   
928.
929.
930.
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