全文获取类型
收费全文 | 20378篇 |
免费 | 1398篇 |
国内免费 | 80篇 |
专业分类
耳鼻咽喉 | 282篇 |
儿科学 | 562篇 |
妇产科学 | 361篇 |
基础医学 | 2564篇 |
口腔科学 | 434篇 |
临床医学 | 2031篇 |
内科学 | 4783篇 |
皮肤病学 | 454篇 |
神经病学 | 1841篇 |
特种医学 | 860篇 |
外科学 | 3179篇 |
综合类 | 166篇 |
一般理论 | 6篇 |
预防医学 | 1553篇 |
眼科学 | 442篇 |
药学 | 1124篇 |
中国医学 | 48篇 |
肿瘤学 | 1166篇 |
出版年
2023年 | 128篇 |
2022年 | 275篇 |
2021年 | 549篇 |
2020年 | 303篇 |
2019年 | 520篇 |
2018年 | 627篇 |
2017年 | 420篇 |
2016年 | 509篇 |
2015年 | 590篇 |
2014年 | 753篇 |
2013年 | 955篇 |
2012年 | 1455篇 |
2011年 | 1456篇 |
2010年 | 881篇 |
2009年 | 776篇 |
2008年 | 1280篇 |
2007年 | 1269篇 |
2006年 | 1229篇 |
2005年 | 1161篇 |
2004年 | 937篇 |
2003年 | 939篇 |
2002年 | 772篇 |
2001年 | 323篇 |
2000年 | 341篇 |
1999年 | 372篇 |
1998年 | 165篇 |
1997年 | 164篇 |
1996年 | 121篇 |
1995年 | 97篇 |
1994年 | 90篇 |
1993年 | 80篇 |
1992年 | 171篇 |
1991年 | 165篇 |
1990年 | 167篇 |
1989年 | 158篇 |
1988年 | 129篇 |
1987年 | 131篇 |
1986年 | 120篇 |
1985年 | 138篇 |
1984年 | 113篇 |
1983年 | 74篇 |
1982年 | 71篇 |
1981年 | 56篇 |
1980年 | 69篇 |
1979年 | 83篇 |
1978年 | 62篇 |
1977年 | 45篇 |
1976年 | 48篇 |
1975年 | 49篇 |
1971年 | 51篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
991.
992.
White matter hyperintensities on magnetic resonance imaging of the brain in children with psychiatric disorders 总被引:4,自引:0,他引:4
The current study sought to determine the prevalence, severity, and location of white matter signal hyperintensities (WMH) on brain magnetic resonance imaging assessments of children and adolescents with psychiatric disorders. Seventy-one percent (N = 934) of children admitted to the McLean Hospital Child and Adolescent inpatient treatment unit were evaluated with the Diagnostic Interview Schedule for Children (DISC) within 7 days of admission during the period 1988 to 1993 (total, 1,308 admissions). Four hundred eight of these subjects (43.7%) were referred for brain magnetic resonance imaging (MRI) scans and became our study subjects (mean age, 12.4 years [SD = 2.7]; male/female, 230/178). Study subjects were grouped according to a hierarchical diagnostic system as follows: schizophrenia (n = 42), bipolar disorder (n = 56), unipolar depression (n = 94), conduct disorder/attention deficit disorder (n = 103), and other neurotic disorders (n = 30). Subjects without any level 2 diagnosis on DISC (n = 83) constituted the comparison group. Bipolar disorder, unipolar depression, and conduct disorder/attention deficit disorder groups were significantly more likely to have severe levels of WMH than the comparison group (prevalence rates: 17.9%, 13.8%, 13.6% v 1.2%). In addition, the bipolar disorder group was significantly more likely to have severe levels of WMH than the schizophrenia group (prevalence rates: 17.9% v 2.4%). The frontal lobes were the predominant locations of WMH in the bipolar disorder and unipolar depression groups (76.9% and 60.0%, respectively) and also the most frequent location for the conduct disorder/attention deficit disorder group (35.7%). The current study reports an increased prevalence and severity of WMH in children with bipolar disorder, unipolar depression, and conduct disorder/attention deficit disorder relative to the comparison group and in children with bipolar disorder compared to those with schizophrenia. The development of brain WMH, especially in the frontal lobes, may play a role in the pathophysiology of affective disorders in children and adolescents. 相似文献
993.
Wolfe GI Barohn RJ Foster BM Jackson CE Kissel JT Day JW Thornton CA Nations SP Bryan WW Amato AA Freimer ML Parry GJ;Myasthenia Gravis-IVIG Study Group 《Muscle & nerve》2002,26(4):549-552
We initiated a randomized, double-blinded, placebo-controlled trial of intravenous immunoglobulin (IVIG) treatment in myasthenia gravis (MG). Patients received IVIG 2 gm/kg at induction and 1 gm/kg after 3 weeks vs. 5% albumin placebo. The primary efficacy measurement was the change in the quantitative MG Score (QMG) at day 42. Fifteen patients were enrolled (6 to IVIG; 9 to placebo) before the study was terminated because of insufficient IVIG inventories. At day 42, there was no significant difference in primary or secondary outcome measurements between the two groups. In a subsequent 6-week open-label study of IVIG, positive trends were observed. 相似文献
994.
Gothelf D Falk B Singer P Kairi M Phillip M Zigel L Poraz I Frishman S Constantini N Zalsman G Weizman A Apter A 《The American journal of psychiatry》2002,159(6):1055-1057
OBJECTIVE: The authors studied weight gain mechanisms and energy balance in patients treated with olanzapine. METHOD: The body mass index of male schizophrenic adolescent inpatients treated with olanzapine (N=10) and of 10 matched patients treated with haloperidol (N=10) were measured at baseline and after 4 weeks of treatment. For the patients treated with olanzapine, caloric intake, resting energy expenditure, and physical activity (determined through accelerometry and heart rate monitoring) were assessed at baseline and after 4 weeks of treatment. RESULTS: Body mass index significantly increased in those treated with olanzapine but not in those given haloperidol. The increase in body mass index was due to an increase in caloric intake without change in diet composition. Olanzapine had no significant effect on resting energy expenditure. Daily energy expenditure was very low before and after treatment. CONCLUSIONS: Olanzapine-induced weight gain is associated with a general increase in caloric intake. 相似文献
995.
Targeting the Mycobacterium tuberculosis 30/32-kDa mycolyl transferase complex as a therapeutic strategy against tuberculosis: Proof of principle by using antisense technology 下载免费PDF全文
996.
997.
998.
Targeting and tailoring physical activity information using print and information technologies 总被引:5,自引:0,他引:5
With the large numbers of physically inactive individuals, it is important that interventions reach a broad spectrum of the population. This paper focuses on targeting and tailoring physical activity information, and the use of mediated interventions, specifically those using print, and other information technologies for promoting physical activity. 相似文献
999.
The effectiveness of two basic cerebral protection devices designed for carotid angioplasty with and without additional aspiration techniques was compared in an in vitro model. During carotid angioplasty, embolization was simulated by injecting polyvinyl alcohol particles of different sizes into the model system. None of the tested devices, all of which were positioned in the internal carotid artery, was able to completely prevent embolization. In the internal carotid artery, the rate of particle capture did not vary among protection devices. However, embolization into the external carotid artery was more frequent with use of the GuideWire, as compared with that with use of the Angioguard. 相似文献
1000.
A person's right to control his or her own body, expressed through the concept of informed consent to medical treatment, has gained worldwide acceptance. Nevertheless, this right may conflict with the state's interest in preserving life in cases where patients refuse treatment in medical emergencies. This paper examines the management of treating acute anaemia in a Jehovah's Witness in Israel who refused blood transfusion on religious grounds. The medical and legal ramifications are discussed in light of the Israeli Patients' Rights Law of 1996. This law established statutory ethics committees which may, under defined conditions of emergency or threat to life, approve treatment against the patient's will. This power, previously vested in the courts, should be used only in extreme circumstances while, in general, patients' wishes and beliefs must be respected. Sensitivity to the legal and ethical aspects involved deserves greater emphasis in medical school curricula. 相似文献