全文获取类型
收费全文 | 1128篇 |
免费 | 81篇 |
国内免费 | 2篇 |
专业分类
耳鼻咽喉 | 12篇 |
儿科学 | 46篇 |
妇产科学 | 8篇 |
基础医学 | 110篇 |
口腔科学 | 32篇 |
临床医学 | 134篇 |
内科学 | 310篇 |
皮肤病学 | 39篇 |
神经病学 | 66篇 |
特种医学 | 86篇 |
外科学 | 185篇 |
综合类 | 12篇 |
预防医学 | 56篇 |
眼科学 | 30篇 |
药学 | 48篇 |
中国医学 | 6篇 |
肿瘤学 | 31篇 |
出版年
2023年 | 7篇 |
2022年 | 27篇 |
2021年 | 59篇 |
2020年 | 36篇 |
2019年 | 51篇 |
2018年 | 51篇 |
2017年 | 30篇 |
2016年 | 36篇 |
2015年 | 41篇 |
2014年 | 65篇 |
2013年 | 70篇 |
2012年 | 113篇 |
2011年 | 101篇 |
2010年 | 48篇 |
2009年 | 40篇 |
2008年 | 57篇 |
2007年 | 53篇 |
2006年 | 48篇 |
2005年 | 40篇 |
2004年 | 25篇 |
2003年 | 30篇 |
2002年 | 24篇 |
2001年 | 7篇 |
2000年 | 10篇 |
1999年 | 16篇 |
1998年 | 6篇 |
1997年 | 8篇 |
1996年 | 9篇 |
1995年 | 9篇 |
1994年 | 7篇 |
1993年 | 5篇 |
1992年 | 9篇 |
1991年 | 2篇 |
1990年 | 7篇 |
1989年 | 3篇 |
1988年 | 4篇 |
1987年 | 8篇 |
1986年 | 3篇 |
1985年 | 5篇 |
1984年 | 2篇 |
1983年 | 2篇 |
1982年 | 3篇 |
1980年 | 3篇 |
1979年 | 7篇 |
1978年 | 5篇 |
1976年 | 2篇 |
1974年 | 3篇 |
1972年 | 2篇 |
1971年 | 5篇 |
1967年 | 2篇 |
排序方式: 共有1211条查询结果,搜索用时 140 毫秒
1.
Behzad Emadi Mojtaba Ghahraman Rezaieh Mansour Sedighi 《Transfusion and apheresis science》2021,60(3):103132
Transfusion transmissible infections (TTIs) have been a public health challenge for the accessibility, quality and safety of blood transfusion. The present study aimed to consider the prevalence and the trends of hepatitis B virus (HBV), hepatitis C virus (HCV), Human T-cell leukemia virus type 1 (HTLV-1), human immunodeficiency virus (HIV) and syphilis across the ten years among retrospective blood donors. A retrospective investigation of blood donors’ data covering the period from 22 May 2009 to 22 May 2019 was done. Data was accumulated and analyzed from Blood Transfusion Center records, pertaining to all donors who were screened for various TTIs using respective immunological techniques. Out of the 682,171 screened donors in the 2009–2019 study period, 2470 (0.36 %) were infected with at least one infectious agent. The overall prevalence of HBV, HCV, HTLV-1, HIV and syphilis were 1700 (0.25 %), 184 (0.027 %), 335 (0.05 %), 4 (0.0.05 %) and 247 (0.036 %), respectively. The study showed male dominated donor pool (96.79 %) with higher prevalence (0.34 %) of TTIs compared to female donors (0.02 %) with 3.21 % population. Despite the low prevalence of TTIs in our study, HBV, HCV, syphilis and HIV have remained a big threat to safe blood transfusion in Iran. Strict adherence to selection criteria, algorithm of donor screening, use of highly sensitive and specific methods for detection of TTIs, regular consultation and health education programs, prevention and sanitization strategies to reduce the risk of TTIs are recommended to reduce the risk of TTIs and ensure the safety of blood transfusion for recipient. 相似文献
2.
3.
4.
5.
6.
Yaotang Wu Guangping Dai Jerome L Ackerman Mirko I Hrovat Melvin J Glimcher Brian D Snyder Ara Nazarian David A Chesler 《Magnetic resonance in medicine》2007,57(3):554-567
Investigators often study rats by microCT to investigate the pathogenesis and treatment of skeletal disorders in humans. However, microCT measurements provide information only on bone mineral content and not the solid matrix. CT scans are often carried out on cancellous bone, which contains a significant volume of marrow cells, stroma, water, and fat, and thus the apparent bone mineral density (BMD) does not reflect the mineral density within the matrix, where the mineral crystals are localized. Water- and fat-suppressed solid-state proton projection imaging (WASPI) was utilized in this study to image the solid matrix content (collagen, tightly bound water, and other immobile molecules) of rat femur specimens, and meet the challenges of small sample size and demanding submillimeter resolution. A method is introduced to recover the central region of k-space, which is always lost in the receiver dead time when free induction decays (FIDs) are acquired. With this approach, points near the k-space origin are sampled under a small number of radial projections at reduced gradient strength. The typical scan time for the current WASPI experiments was 2 hr. Proton solid-matrix images of rat femurs with 0.4-mm resolution and 12-mm field of view (FOV) were obtained. This method provides a noninvasive means of studying bone matrix in small animals. 相似文献
7.
8.
9.
kappa-Opioid receptor agonists (e.g., enadoline or U-50,488) increase the locomotor activity of preweanling rats, while the same drugs depress the locomotor activity of adults. Curiously, direct stimulation of dopamine (DA) D2-like receptors fully attenuates the U-50,488-induced locomotor activity of preweanling rats. The purpose of the present study was to determine whether indirect DA agonists (i.e., cocaine, methylphenidate, and amphetamine) would also attenuate U-50,488's behavioral effects. In two experiments, 17-day-old rats were injected with saline or U-50,488 (5 mg/kg, sc) and locomotor activity and stereotyped sniffing were assessed. After 20 min, the saline- and U-50,488-pretreated rats were injected with saline, cocaine (5, 10, or 20 mg/kg, i.p.), methylphenidate (10 or 20 mg/kg, i.p.), amphetamine (2.5 or 5 mg/kg, i.p.), or the direct D2-like receptor agonist NPA (1 mg/kg, i.p.). As expected, U-50,488 dramatically enhanced the locomotor activity of 17-day-old rats, while attenuating the stereotyped sniffing caused by indirect and direct DA agonists. All three indirect DA agonists augmented U-50,488's locomotor activating effects across the initial 10 min of testing and then activity declined to U-50,488 control values. Direct stimulation of DA receptors produced nearly opposite effects because NPA attenuated U-50,488-induced locomotor activity across the entire testing session. It is uncertain why direct and indirect DA agonists affected U-50,488-induced locomotor activity differently, but the relative amount of DA D1-like receptor activation is probably not responsible. 相似文献
10.
Carrie Minnelli Maziar Riazy Ryuji Ohashi Jolanta Kowalewska Nicolae Leca Behzad Najafian Kelly D. Smith Roberto F. Nicosia Charles E. Alpers Shreeram Akilesh 《Transplantation proceedings》2021,53(5):1554-1561
BackgroundEarly dysfunction of renal allografts may be associated with vascular injury, which raises the specter of active rejection processes that require medical intervention. In our practice, we have encountered patients who present with delayed graft function and demonstrate a unique pattern of endothelial cell injury that raises concern for rejection in their biopsy. Therefore, we sought to systematically determine the biopsy characteristics and outcome of these patients.MethodsDuring a 17-year period at the University of Washington in Seattle, United States, we identified 24 cases of a distinct arterial vasculopathy presenting in the first year posttransplantation. This early transplant arteriopathy (ETA) is characterized by endothelial cell swelling and intimal edema but without the intimal arteritis that defines vascular rejection.ResultsApproximately 1% of transplant biopsies during the study period showed ETA, almost all of which were in deceased donor organs (96%), and most presented with delayed graft function (54%) or increased serum creatinine (38%) soon after transplantation (median 13 days; range, 5-139). In this study, 77% of patients were managed expectantly, with only 2 patients (7.6%) subsequently developing acute vascular rejection. Except for 1 patient who died, all patients had functioning allografts at 1 year follow-up.ConclusionRecognizing ETA and distinguishing it from vascular rejection is important to prevent over-treatment because most patients appear to recover allograft function rapidly with expectant management. 相似文献