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   126608篇
  免费   6725篇
  国内免费   587篇
耳鼻咽喉   1221篇
儿科学   3134篇
妇产科学   2244篇
基础医学   16696篇
口腔科学   2825篇
临床医学   12149篇
内科学   26890篇
皮肤病学   2375篇
神经病学   12075篇
特种医学   5070篇
外国民族医学   5篇
外科学   18842篇
综合类   1541篇
现状与发展   1篇
一般理论   114篇
预防医学   8948篇
眼科学   2587篇
药学   8594篇
  13篇
中国医学   190篇
肿瘤学   8406篇
  2024年   317篇
  2023年   725篇
  2022年   1021篇
  2021年   2326篇
  2020年   1673篇
  2019年   2379篇
  2018年   2795篇
  2017年   2140篇
  2016年   2438篇
  2015年   2837篇
  2014年   4131篇
  2013年   5513篇
  2012年   8485篇
  2011年   9032篇
  2010年   5157篇
  2009年   4881篇
  2008年   8301篇
  2007年   8787篇
  2006年   8355篇
  2005年   8447篇
  2004年   8046篇
  2003年   7679篇
  2002年   7230篇
  2001年   1270篇
  2000年   988篇
  1999年   1382篇
  1998年   1712篇
  1997年   1323篇
  1996年   1162篇
  1995年   1051篇
  1994年   924篇
  1993年   916篇
  1992年   654篇
  1991年   644篇
  1990年   521篇
  1989年   521篇
  1988年   491篇
  1987年   480篇
  1986年   434篇
  1985年   452篇
  1984年   534篇
  1983年   480篇
  1982年   605篇
  1981年   577篇
  1980年   487篇
  1979年   312篇
  1978年   302篇
  1977年   353篇
  1976年   289篇
  1975年   262篇
排序方式: 共有10000条查询结果,搜索用时 218 毫秒
11.

Background

Physicians treating nonvalvular atrial fibrillation (AF) assess stroke and bleeding risks when deciding on anticoagulation. The agreement between empirical and physician-estimated risks is unclear. Furthermore, the association between patient and physician sex and anticoagulation decision-making is uncertain.

Methods

We pooled data from 2 national primary care physician chart audit databases of patients with AF (Facilitating Review and Education to Optimize Stroke Prevention in Atrial Fibrillation and Coordinated National Network to Engage Physicians in the Care and Treatment of Patients with Atrial Fibrillation Chart Audit) with a combined 1035 physicians (133 female, 902 male) and 10,927 patients (4567 female and 6360 male).

Results

Male physicians underestimated stroke risk in female patients and overestimated risk in male patients. Female physicians estimated stroke risk well in female patients but underestimated the risk in male patients. Risk of bleeding was underestimated in all. Despite differences in risk assessment by physician and patient sex, > 90% of patients received anticoagulation across all subgroups. There was modest agreement between physician estimated and calculated (ie, CHADS2 score) stroke risk: Kappa scores were 0.41 (0.35-0.47) for female physicians and 0.34 (0.32-0.36) for male physicians.

Conclusions

Our study is the first to examine the association between patient and physician sex influences and stroke and bleeding risk estimation in AF. Although there were differences in agreement between physician estimated stroke risk and calculated CHADS2 scores, these differences were small and unlikely to affect clinical practice; further, despite any perceived differences in the accuracy of risk assessment by sex, most patients received anticoagulation.  相似文献   
12.
Increasing costs of research and development in the pharmaceutical industry has necessitated a growing interest in the early prediction of human pharmacokinetics of drug candidates. Of growing interest is the need to understand oral absorption, the most common route of small molecule drug administration. The fraction of dose absorbed (%Fa) is considered a critical yet challenging parameter to predict. A kinetic model has been developed and tested to provide an early prediction of the fraction dose absorbed in humans. Unlike the traditional plug-flow model, this model assumes first-order kinetics to estimate the amount of drug present in the stomach and small intestine as a function of time and calculates the amount of drug released and absorbed during the transit. Other variables can be included in calculation as a function of time to better mimic the physiological condition with this approach. Absorption efficiency is assigned along with %Fa to give a quantitative estimate of the limiting factor for oral absorption. The model was tested with literature and in-house compounds. It was found that this model gives a good prediction of human %Fa with a correction coefficient (R2) of 0.8 and greater between predicted and reported %Fa for all compounds.  相似文献   
13.
14.
The aim of this study was to determine whether loratadine, a selective inverse agonist of peripheral histamine H1 receptors, would reduce emotional blushing. Loratadine (10?mg) or placebo was administered orally one hour before 31 healthy participants sang a children's nursery rhyme to evoke embarrassment and blushing. Skin blood flow was monitored via a laser Doppler probe attached to the cheek. Increases in facial blood flow while participants sang were greater in the loratadine than the placebo group (mean increase?±?standard deviation 71?±?52% in the loratadine group versus 35?±?37%, p?=?.036). However, perceptions of blushing were similar in both groups. These findings suggest that loratadine augmented blushing rather than inhibiting it. Thus, histamine released during blushing may inhibit acute increases in facial blood flow by evoking H1 receptor-mediated vasoconstriction.  相似文献   
15.
The list of motives by Kanin (1994) is the most cited list of motives to file a false allegation of rape. Kanin posited that complainants file a false allegation out of revenge, to produce an alibi or to get sympathy. A new list of motives is proposed in which gain is the predominant factor. In the proposed list, complainants file a false allegation out of material gain, emotional gain, or a disturbed mental state. The list can be subdivided into eight different categories: material gain, alibi, revenge, sympathy, attention, a disturbed mental state, relabeling, or regret. To test the validity of the list, a sample of 57 proven false allegations were studied at and provided by the National Unit of the Dutch National Police (NU). The complete files were studied to ensure correct classification by the NU and to identify the motives of the complainants. The results support the overall validity of the list. Complainants were primarily motivated by emotional gain. Most false allegations were used to cover up other behavior such as adultery or skipping school. Some complainants, however, reported more than one motive. A large proportion, 20% of complainants, said that they did not know why they filed a false allegation. The results confirm the complexity of motivations for filing false allegations and the difficulties associated with archival studies. In conclusion, the list of Kanin is, based on the current results, valid but insufficient to explain all the different motives of complainants to file a false allegation.  相似文献   
16.
17.

Background

Pharmacist participation in school medication management (MM) is minimal. School nurses are responsible for increasingly complex medication administration and management in schools.

Objectives

The purpose of this study was to 1) assess the MM needs of school nurses in Minnesota, and 2) determine if and how interprofessional partnerships between nurses and pharmacists might optimize MM for students.

Methods

Researchers from the University of Minnesota College of Pharmacy, School Nurse Organization of Minnesota, and Minnesota Department of Health conducted a 32-item online survey of school nurses.

Results

Nurses administered the majority of medications at their school (69.9%) compared with unlicensed assistive personnel (29%). Stimulants (37.7%), asthma medications (25.7%), over-the-counter analgesics (17.8%), and insulin (6.6%) were the most commonly administered drug therapies. A clear majority of school nurses were interested in partnering with pharmacists: 90.3% thought that a pharmacist could assist with MM, 80% would consult with a pharmacist, and 12.3% reported that they already have informal access to a pharmacist. Topics that nurses would discuss with a pharmacist included new medications (71.6%), drug–drug interactions (67.1%), proper administration (52%), and storage (39.4%). The top MM concerns included 1) availability of students' medications and required documentation, 2) health literacy, 3) pharmacist consultations, 4) lack of time available for nurses to follow up with and evaluate students, 5) family-centered care, 6) delegation, 7) communication, and 8) professional development.

Conclusion

Although the majority of school nurses surveyed indicated that partnerships with pharmacists would improve school MM, few had a formal relationship. Interprofessional partnerships focused on MM and education are high on the list of services that school nurses would request of a consultant pharmacist. Study results suggest that there are opportunities for pharmacists to collaborate with school nurses; further study is necessary to advance high-quality MM for students in Minnesota schools.  相似文献   
18.

Background

Poor medication adherence is an ongoing issue, and contributes to increased hospitalizations and healthcare costs. Although most adverse effects are rare, the perceived risk of adverse effects may contribute to low adherence rates.

Objectives

The objective of this study was to determine how adverse effect likelihood and pharmacist counseling on adverse effect prevention affects individuals': (1) willingness to use a hypothetical medication and (2) perceptions of medication safety.

Methods

This study used a 3 × 3 experimental design. Participants (n = 601) viewed a hypothetical scenario asking them to imagine being prescribed an anti-asthma medication that could cause fungal infections of the throat. Participants were randomized to 1 of 9 scenarios that differed on: probability of developing an infection (5%, 20%, no probability mentioned) and whether they were told how to reduce the risk of infection (no prevention strategy discussed, prevention strategy discussed, prevention strategy discussed with explanation for how it works). Participants were recruited through Amazon Mechanical Turk.

Results

Participants were less willing to take the medication (F = 12.86, p < 0.0001) and considered it less safe (F = 13.11, p < 0.0001) when the probability of fungal infection was presented as 20% compared to 5% or when no probability information was given. Participants were more willing to take the medication (F = 11.78, p < 0.0001) and considered it safer (F = 11.17, p < 0.0001) when a prevention strategy was given. Finally, there was a non-statistically significant interaction between the probability and prevention strategy information such that provision of prevention information reduced the effect of variation in the probability of infection on both willingness to use the medication and perceived medication safety.

Conclusions

Optimal risk communication involves more than informing patients about possible adverse effects. Pharmacists could potentially improve patient acceptance of therapeutic recommendations, and allay medication safety concerns, by counseling about strategies patients can implement to reduce the perceived risk of adverse effects.  相似文献   
19.
20.
Myasthenia gravis (MG) is an autoimmune disease of the neuromuscular junction. Most patients have pathogenic autoantibodies against the acetylcholine receptor (AChR). In the last years a novel subpopulation of MG patients has been described that harbors antibodies against low-density lipoprotein receptor-related protein 4 (Lrp4), another postsynaptic neuromuscular antigen. In early-onset AChR MG (EOMG), the thymus plays an important role in immunopathogenesis, and early thymectomy is beneficial. It is still unknown if the thymus plays any role in Lrp4-MG. In this pilot study, we compared thymus samples from four patients with Lrp4-MG (one pre-treated with immunosuppressive drugs), four non-MG controls and five EOMG patients (not pretreated with immunosuppressive drugs). Immunohistochemistry of the Lrp4-MG thymi revealed normal architecture, with normal numbers and distribution of B-cells, lymphoid follicles and Hassall's corpuscles. Primary CD23+ lymphoid follicles were similarly infrequent in Lrp4-MG and control thymic sections. In none of the control or Lrp4-MG thymi did we find secondary follicles with CD10+ germinal centers. These were evident in 2 of the 5 EOMG thymi, where primary lymphoid follicles were also more frequent on average, thus showing considerable heterogeneity between patients. Even if characteristic pathological thymic changes were not observed in the Lrp4 subgroup, we cannot exclude a role for the thymus in Lrp4-MG pathogenesis, since one Lrp4-MG patient went into clinical remission after thymectomy alone (at one year follow-up) and one more improved after thymectomy in combination with immunosuppressive therapy.  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