全文获取类型
收费全文 | 24365篇 |
免费 | 1980篇 |
国内免费 | 79篇 |
专业分类
耳鼻咽喉 | 130篇 |
儿科学 | 932篇 |
妇产科学 | 754篇 |
基础医学 | 3372篇 |
口腔科学 | 363篇 |
临床医学 | 3276篇 |
内科学 | 4481篇 |
皮肤病学 | 363篇 |
神经病学 | 2952篇 |
特种医学 | 388篇 |
外科学 | 2137篇 |
综合类 | 372篇 |
一般理论 | 47篇 |
预防医学 | 3192篇 |
眼科学 | 448篇 |
药学 | 1608篇 |
中国医学 | 34篇 |
肿瘤学 | 1575篇 |
出版年
2023年 | 227篇 |
2022年 | 269篇 |
2021年 | 538篇 |
2020年 | 388篇 |
2019年 | 586篇 |
2018年 | 650篇 |
2017年 | 504篇 |
2016年 | 512篇 |
2015年 | 599篇 |
2014年 | 846篇 |
2013年 | 1204篇 |
2012年 | 1756篇 |
2011年 | 1795篇 |
2010年 | 977篇 |
2009年 | 931篇 |
2008年 | 1472篇 |
2007年 | 1610篇 |
2006年 | 1622篇 |
2005年 | 1491篇 |
2004年 | 1477篇 |
2003年 | 1363篇 |
2002年 | 1264篇 |
2001年 | 300篇 |
2000年 | 236篇 |
1999年 | 246篇 |
1998年 | 268篇 |
1997年 | 225篇 |
1996年 | 174篇 |
1995年 | 167篇 |
1994年 | 128篇 |
1993年 | 153篇 |
1992年 | 146篇 |
1991年 | 143篇 |
1990年 | 134篇 |
1989年 | 116篇 |
1988年 | 112篇 |
1987年 | 103篇 |
1986年 | 99篇 |
1985年 | 103篇 |
1984年 | 101篇 |
1983年 | 93篇 |
1982年 | 95篇 |
1981年 | 82篇 |
1980年 | 92篇 |
1979年 | 61篇 |
1978年 | 57篇 |
1977年 | 58篇 |
1976年 | 65篇 |
1975年 | 56篇 |
1974年 | 57篇 |
排序方式: 共有10000条查询结果,搜索用时 0 毫秒
101.
Johnson Bryan A. Lindgren Bruce R. Blaes Anne H. Parsons Helen M. LaRocca Christopher J. Farah Ronda Hui Jane Yuet Ching 《Annals of surgical oncology》2021,28(10):5668-5676
Annals of Surgical Oncology - Telemedicine was adopted to minimize exposure risks for patients and staff during the coronavirus disease 2019 pandemic. This study measured patient satisfaction and... 相似文献
102.
Woodson W. Smelser Joseph Hogan Randall Joshua Caldwell Katherine Glavin Eugene K. Lee Ajay Nangia Jeffrey M. Holzbeierlein 《Urologic oncology》2021,39(7):435.e23-435.e31
BackgroundPrior studies have demonstrated declines in androgen levels in men with cancer and patients undergoing anesthesia and surgery. In this study, we hypothesized that decreased serum androgen levels are prevalent in male patients undergoing radical cystectomy (RC) for bladder cancer and that it persists in the postoperative period. We characterized perioperative androgen hormonal profiles and examined for associated changes indicative of sarcopenia on computed tomography scans in men undergoing RC.MethodsWe implemented a prospective observational trial in men with newly diagnosed non-metastatic bladder cancer undergoing RC. Baseline pre-operative total testosterone (TT), free testosterone (FT), and luteinizing hormone (LH) were obtained on morning lab draws with 30 days of surgery. TT and FT were then repeated on postoperative days (POD) 2, 3, 30, and 90. The threshold for normal TT was defined as >300 ng/dl, consistent with the AUA Guidelines for Evaluation and Management of Testosterone Deficiency. We evaluated postoperative changes in weight and psoas muscle cross-sectional area using computed tomography scans to assess for sarcopenic changes.ResultsUnivariable statistical analysis was performed. 25 patients were enrolled. The mean patient age was 68.9 years. The mean pre-operative TT was 308 ng/dl, and 12/23 (52.5%) patients had low testosterone. Mean TT onPOD 2 and 3 were 166 ng/dl and 161 ng/dl, respectively (range 24–345). 19/20 (95%) of men who had morning lab draws had decreased TT. The mean TT at 30 days was 253 ng/dl with 37.5% of men having low TT. Mean TT at 90 days was 306 ng/dl. The mean FT levels were 43 ng/dl, 29.25 ng/dl, 28.2 ng/dl, 40.89 ng/dl, and 42.62 ng/dl at baseline, POD 2, POD 3, POD 30, and POD 90, respectively. Mean LH at baseline was 9.9 IU/L. Average weight loss at 30- and 90- days postop was -4.29 and -4.38 kilograms, respectively. Weight loss was persistent with only 3/23 (13%) returning to their presurgery weight by 90 days. Despite significant declines in weight and perioperative TT, no significant differences in psoas muscle cross-sectional area were observed (net change -92 mm2, P= 0.13)ConclusionsPerioperative disruption of androgen levels is prevalent in men undergoing RC. Our trial demonstrates a pre-op, immediate postop, 30- and 90-day postoperative prevalence of low TT of 52%, 95%, 63%, and 37.5%, respectively. Significant changes in baseline weight were noted, although no significant changes in psoas muscle cross-sectional area were observed, limiting conclusions regarding a link between changes in androgens and sarcopenia in this setting. 相似文献
103.
104.
105.
Recent work points to the importance of changes in gene expression patterns in species-specific differences. Here, we investigate the evolution of the nematode lin-48 ovo gene. lin-48 is expressed in several cells in both Caenorhabditis elegans and Caenorhabditis briggsae, but acts in the excretory duct cell only in C. elegans. We find the differences result both from alterations in the cis-regulatory sequences and in proteins that mediate lin-48 expression. One factor that contributes to the species differences is the bZip protein CES-2. Our results indicate the accumulation of several regulatory changes affecting one gene can contribute to evolutionary change. 相似文献
106.
Willismd P Hogan K Spinks M Moody J Garrish N 《The Health service journal》1994,104(5397):suppl 1-suppl 7
107.
Familial endometriosis 总被引:11,自引:0,他引:11
Stephen Kennedy Helen Mardon David Barlow 《Journal of assisted reproduction and genetics》1995,12(1):32-34
Purpose
The study aimed to identify families with endometriosis and to document disease seventy within the families and the clinical characteristics of the affected women.Results
Two hundred and thirty women with surgically confirmed endometriosis in 100 families were identified. The families consisted of 19 mother-daughter pairs, 1 set of cousins and 56 sister pairs. There were 5 families with 3 affected sisters, 1 family with 5 affected sisters, and 18 families with 3 affected members in more than one generation. The mean age at the onset of symptoms and the mean age at surgical diagnosis was 22.1±8.8 SD (range 10–46) and 31.8±7.9 SD (range 15–56) years respectively. Seventy-nine women (34.3%) had revised AFS Stage I–II disease, and 151 (65.7%) had revised AFS Stage III–IV disease.Conclusion
The study confirms a familial tendency for endometriosis and supports the hypothesis that endometriosis has a genetic basis.Presented at the 50th Annual Meeting of the American Fertility Society, San Antonio, Texas, November 5–10, 1994. 相似文献
108.
Kulier AH Novalija E Hogan Q Vicenzi MN Woehlck HJ Bajic J Atlee JL Bosnjak ZJ 《Anesthesia and analgesia》1999,89(6):1393-1399
Perioperative malignant ventricular tachyarrhythmias pose an imminent clinical danger by potentially precipitating myocardial ischemia and severely compromising hemodynamics. Thus, immediate and effective therapy is required, which is not always provided by currently recommended IV drug regimens, indicating a need for more effective drugs. We examined antiarrhythmic effects of the new benzofurane compound E 047/1 on spontaneous ventricular tachyarrhythmia in a conscious dog model. One day after experimental myocardial infarction, 40 dogs exhibiting tachyarrhythmia randomly received (bolus plus 1-h infusion) E 047/1 6 mg/kg plus 6 mg x kg(-1) x h(-1), lidocaine 1 mg/kg plus 4.8 mg x kg(-1) x h(-1), flecainide 1 mg/kg plus 0.05 mg x kg(-1) x h(-1), amiodarone 10 mg/kg plus 1.8 mg x kg(-1) x h(-1), or bretylium 10 mg/kg plus 20 mg x kg(-1) x h(-1). Electrocardiogram was evaluated for number of premature ventricular contractions (PVC), normally conducted beats originating from the sinoatrial node, and episodes of ventricular tachycardia. Immediately after the bolus, E 047/1 reduced PVCs by 46% and increased sinoatrial beats from 4 to 61 bpm. The ratio of PVCs to total beats decreased from 98% to 58%. Amiodarone and flecainide exhibited antiarrhythmic effects with delayed onset. Lidocaine did not suppress PVCs significantly, and bretylium was proarrhythmic. The antiarrhythmic E 047/1 has desirable features, suppressing ischemia-induced ventricular tachyarrhythmia quickly and efficiently, and may be a useful addition to current therapeutic regimens. IMPLICATIONS: Life-threatening arrhythmias of the heart after myocardial infarction or ischemia may be treated quickly and efficiently by the new drug E 047/1. 相似文献
109.
Robot training enhanced motor outcome in patients with stroke maintained over 3 years 总被引:4,自引:0,他引:4
In an attempt to improve motor recovery of the upper limb after stroke, we added a robot (MIT-Manus) experience that provided additional goal-directed sensorimotor activity to standard rehabilitation treatments. The first trial produced a significant decrease in motor impairment in the upper limb for the treated group. In re-evaluating 12 of those 20 patients, nearly 3 years later, robot-trained patients showed further significant decreases in impairment measures of the affected limb. The groups were comparable at the start of the study. 相似文献
110.
Hogan P 《Australian family physician》1999,28(2):169-170