全文获取类型
收费全文 | 768篇 |
免费 | 37篇 |
国内免费 | 28篇 |
专业分类
儿科学 | 31篇 |
妇产科学 | 18篇 |
基础医学 | 71篇 |
口腔科学 | 14篇 |
临床医学 | 62篇 |
内科学 | 121篇 |
皮肤病学 | 16篇 |
神经病学 | 14篇 |
特种医学 | 158篇 |
外科学 | 54篇 |
综合类 | 127篇 |
预防医学 | 41篇 |
眼科学 | 7篇 |
药学 | 61篇 |
1篇 | |
中国医学 | 1篇 |
肿瘤学 | 36篇 |
出版年
2023年 | 7篇 |
2022年 | 8篇 |
2021年 | 16篇 |
2020年 | 6篇 |
2019年 | 11篇 |
2018年 | 16篇 |
2017年 | 11篇 |
2016年 | 10篇 |
2015年 | 11篇 |
2014年 | 14篇 |
2013年 | 28篇 |
2012年 | 24篇 |
2011年 | 20篇 |
2010年 | 29篇 |
2009年 | 35篇 |
2008年 | 26篇 |
2007年 | 36篇 |
2006年 | 24篇 |
2005年 | 15篇 |
2004年 | 18篇 |
2003年 | 10篇 |
2002年 | 12篇 |
2001年 | 15篇 |
2000年 | 12篇 |
1999年 | 12篇 |
1998年 | 40篇 |
1997年 | 38篇 |
1996年 | 40篇 |
1995年 | 24篇 |
1994年 | 21篇 |
1993年 | 21篇 |
1992年 | 9篇 |
1991年 | 9篇 |
1990年 | 9篇 |
1989年 | 27篇 |
1988年 | 20篇 |
1987年 | 16篇 |
1986年 | 21篇 |
1985年 | 18篇 |
1984年 | 5篇 |
1983年 | 5篇 |
1982年 | 17篇 |
1981年 | 9篇 |
1980年 | 13篇 |
1978年 | 6篇 |
1977年 | 9篇 |
1976年 | 9篇 |
1975年 | 7篇 |
1955年 | 2篇 |
1953年 | 2篇 |
排序方式: 共有833条查询结果,搜索用时 46 毫秒
21.
Liu SC; Palek J; Yi SJ; Nichols PE; Derick LH; Chiou SS; Amato D; Corbett JD; Cho MR; Golan DE 《Blood》1995,86(1):349-358
Southeast Asian ovalocytosis (SAO) is an asymptomatic trait characterized by rigid, poorly deformable red cells that resist invasion by several strains of malaria parasites. The underlying molecular genetic defect involves simple heterozygous state for a mutant band 3 protein, which contains a deletion of amino acids 400 through 408, linked with a Lys 56-to-Glu substitution (band 3-Memphis polymorphism). To elucidate the contribution of the mutant SAO band 3 protein to increased SAO red blood cell (RBC) rigidity, we examined the participation of the mutant SAO band 3 protein in increased band 3 attachment to the skeleton and band 3 oligomerization. We found first that SAO RBC skeletons retained more band 3 than normal cells and that this increased retention preferentially involved the mutant SAO band 3 protein. Second, SAO RBCs contained a higher percentage of band 3 oligomer-ankyrin complexes than normal cells, and these oligomers were preferentially enriched by the mutant SAO protein. At the ultrastructural level, the increased oligomer formation of SAO RBCs was reflected by stacking of band 3-containing intramembrane particles (IMP) into longitudinal strands. The IMP stacking was not reversed by treating SAO RBCs in alkaline pH (pH 11), which is known to weaken ankyrin-band 3 interactions, or by removing the cytoplasmic domain of band 3 from SAO membranes with trypsin. Finally, we found that band 3 protein in intact SAO RBCs exhibited a markedly decreased rotational mobility, presumably reflecting the increased oligomerization and the membrane skeletal association of the SAO band 3 protein. We propose that the mutant SAO band 3 has an increased propensity to form oligomers, which appear as longitudinal strands of IMP and exhibit increased association with membrane skeleton. This band 3 oligomerization underlies the increase in membrane rigidity by precluding membrane skeletal extension, which is necessary for membrane deformation. 相似文献
22.
Fred Stephen Sarfo Albert Akpalu Ansumana Bockarie Lambert Appiah Samuel Blay Nguah Nana Kwame Ayisi-Boateng Sheila Adamu Christiana Neizer Agnes Arthur Richard Nyamekye Kwabena Agyenim-Boateng Raelle Tagge Nathaniel Adusei-Mensah Michael Ampofo Ruth Laryea Arti Singh John Humphry Amuasi Bruce Ovbiagele 《Journal of stroke and cerebrovascular diseases》2021,30(8):105888
ObjectivesThe Sub-Saharan African (SSA) region now has the highest estimated effect size of hypertension for stroke causation worldwide. An urgent priority for countries in SSA is to develop and test self-management interventions to control hypertension among those at highest risk of adverse outcomes. Thus the overall objective of the Phone-based Intervention under Nurse Guidance after Stroke II study (PINGS-2) is to deploy a hybrid study design to assess the efficacy of a theoretical-model-based, mHealth technology-centered, nurse-led, multi-level integrated approach to improve longer term blood pressure (BP) control among stroke survivors.Materials and methodsA phase III randomized controlled trial involving 500 recent stroke survivors to be enrolled across 10 Ghanaian hospitals. Using a computer-generated sequence, patients will be randomly assigned 1:1 into the intervention or usual care arms. The intervention comprises of (i) home BP monitoring at least once weekly with nurse navigation for high domiciliary BP readings; (2) medication reminders using mobile phone alerts and (3) education on hypertension and stroke delivered once weekly via audio messages in preferred local dialects. The intervention will last for 12 months. The control group will receive usual care as determined by local guidelines. The primary outcome is the proportion of patients with systolic BP <140 mm Hg at 12 months. Secondary outcomes will include medication adherence, self-management of hypertension, major adverse cardiovascular events, health related quality of life and implementation outcomes.ConclusionAn effective PINGS intervention can potentially be scaled up and disseminated across healthcare systems in low-and-middle income countries challenged with resource constraints to reduce poor outcomes among stroke survivors. 相似文献
23.
JV Lodhia S Appiah P Tcherveniakov P Krysiak 《Annals of the Royal College of Surgeons of England》2015,97(2):e27-e29
Iatrogenic injury accounts for the second most common cause of acquired diaphragmatic hernias after penetrating trauma. An increased incidence of these hernias has been observed with the widespread use of laparoscopic surgery. We present the case of a 65-year-old woman who initially underwent sigmoid resection for an adenocarcinoma and a subsequent liver resection for metastasis. She was noted to have a left lower lobe pulmonary nodule on surveillance computed tomography, for which she underwent a mini-thoracotomy for a planned resection. At the time of surgery, the pulmonary nodule was discovered to be a diaphragmatic hernia, most probably of iatrogenic origin. We discuss the difficulty in diagnosis given her history and the location of such a lesion. 相似文献
24.
25.
26.
Background
The ethnic usage of exotics and indigenous problem plants is a highly debated topic, as legislative requirements over-shadow their potential medicinal value, particularly to treat sexually transmitted infections (STIs). Limited information exists regarding their medicinal value among the Bapedi.Objectives
To ascertain the importance of exotics and indigenous problem plants in the treatment of STIs, a major global primary health care challenge.Methods
A field observation and semi-structured questionnaire focussing on species diversity, types of STIs treated and medicinal preparation as well as application was used to collect data from 34 traditional healers.Results
Seven exotics and three indigenous problem species were identified. These species were used to treat four STIs; with Catharanthus roseus illustrating its dominance in the treatment of gonorrhoea. Some medicinal species used by Bapedi traditional healers have been validated through scientific research or through their extensive use by various cultures in South Africa and other parts of Africa. To the best of our knowledge Alternanthera pungens, Caesalpinia decapetala, Cinnamomum verum, and Citrullus lanatus are reported for the first time in the treatment of the investigated STIs.Conclusions
Exotic and indigenous problem species constitute an important component of the STIs treatment protocol. Their utilization by Bapedi cautions against the narrow-minded approach of indiscriminate eradication, as these species can play a significant role in the primary health care needs of socio-economic vulnerable people. 相似文献27.
MJ Hwang A Bhangu CE Webster DM Bowley MX Gannon SS Karandikar 《Annals of the Royal College of Surgeons of England》2014,96(5):343-347
Introduction
In 2009 the Department of Health instructed McKinsey & Company to provide advice on how commissioners might achieve world class National Health Service productivity. Asymptomatic inguinal hernia repair was identified as a potentially cosmetic procedure, with limited clinical benefit. The Birmingham and Solihull primary care trust cluster introduced a policy of watchful waiting for asymptomatic inguinal hernia, which was implemented across the health economy in December 2010. This retrospective cohort study aimed to examine the effect of a change in clinical commissioning policy concerning elective surgical repair of asymptomatic inguinal hernias.Methods
A total of 1,032 patients undergoing inguinal hernia repair in the 16 months after the policy change were compared with 978 patients in the 16 months before. The main outcome measure was relative proportion of emergency repair in groups before and after the policy change. Multivariate binary logistic regression was used to adjust the main outcome for age, sex and hernia type.Results
The period after the policy change was associated with 59% higher odds of emergency repair (3.6% vs 5.5%, adjusted odds ratio [OR]: 1.59, 95% confidence interval [CI]: 1.03–2.47). In turn, emergency repair was associated with higher odds of adverse events (4.7% vs 18.5%, adjusted OR: 3.68, 95% CI: 2.04–6.63) and mortality (0.1% vs 5.4%, p<0.001, Fisher’s exact test).Conclusions
Introduction of a watchful waiting policy for asymptomatic inguinal hernias was associated with a significant increase in need for emergency repair, which was in turn associated with an increased risk of adverse events. Current policies may be placing patients at risk. 相似文献28.
29.
Mahmoud Salama M. Lambertini MS Christianson Y. Jayasinghe A. Anazodo M. De Vos F. Amant C. Stern L. Appiah T. L. Woodard R. A. Anderson L. M. Westphal R. E. Leach K. A. Rodriguez-Wallberg P. Patrizio Teresa K. Woodruff 《Journal of assisted reproduction and genetics》2022,39(2):505
PurposeAs a further step to elucidate the actual diverse spectrum of oncofertility practices for breast cancer around the globe, we present and discuss the comparisons of oncofertility practices for breast cancer in limited versus optimum resource settings based on data collected in the Repro-Can-OPEN Study Part I & II.MethodsWe surveyed 39 oncofertility centers including 14 in limited resource settings from Africa, Asia & Latin America (Repro-Can-OPEN Study Part I), and 25 in optimum resource settings from the United States, Europe, Australia and Japan (Repro-Can-OPEN Study Part II). Survey questions covered the availability of fertility preservation and restoration options offered to young female patients with breast cancer as well as the degree of utilization.ResultsIn the Repro-Can-OPEN Study Part I & II, responses for breast cancer and calculated oncofertility scores showed the following characteristics: (1) higher oncofertility scores in optimum resource settings than in limited resource settings especially for established options, (2) frequent utilization of egg freezing, embryo freezing, ovarian tissue freezing, GnRH analogs, and fractionation of chemo- and radiotherapy, (3) promising utilization of oocyte in vitro maturation (IVM), (4) rare utilization of neoadjuvant cytoprotective pharmacotherapy, artificial ovary, and stem cells reproductive technology as they are still in preclinical or early clinical research settings, (5) recognition that technical and ethical concerns should be considered when offering advanced and innovative oncofertility options.ConclusionsWe presented a plausible oncofertility best practice model to guide oncofertility teams in optimizing care for breast cancer patients in various resource settings. 相似文献
30.