全文获取类型
收费全文 | 1030篇 |
免费 | 81篇 |
国内免费 | 107篇 |
专业分类
耳鼻咽喉 | 1篇 |
儿科学 | 38篇 |
妇产科学 | 37篇 |
基础医学 | 139篇 |
口腔科学 | 32篇 |
临床医学 | 164篇 |
内科学 | 219篇 |
皮肤病学 | 11篇 |
神经病学 | 108篇 |
特种医学 | 88篇 |
外科学 | 79篇 |
综合类 | 44篇 |
预防医学 | 67篇 |
眼科学 | 6篇 |
药学 | 146篇 |
中国医学 | 5篇 |
肿瘤学 | 34篇 |
出版年
2021年 | 8篇 |
2020年 | 6篇 |
2019年 | 11篇 |
2018年 | 10篇 |
2017年 | 12篇 |
2016年 | 17篇 |
2015年 | 23篇 |
2014年 | 20篇 |
2013年 | 31篇 |
2012年 | 46篇 |
2011年 | 43篇 |
2010年 | 36篇 |
2009年 | 38篇 |
2008年 | 36篇 |
2007年 | 93篇 |
2006年 | 40篇 |
2005年 | 45篇 |
2004年 | 43篇 |
2003年 | 36篇 |
2002年 | 32篇 |
2001年 | 34篇 |
2000年 | 31篇 |
1999年 | 20篇 |
1998年 | 50篇 |
1997年 | 39篇 |
1996年 | 43篇 |
1995年 | 20篇 |
1994年 | 26篇 |
1993年 | 15篇 |
1992年 | 17篇 |
1991年 | 18篇 |
1990年 | 24篇 |
1989年 | 25篇 |
1988年 | 22篇 |
1987年 | 34篇 |
1986年 | 20篇 |
1985年 | 17篇 |
1984年 | 16篇 |
1983年 | 11篇 |
1982年 | 7篇 |
1981年 | 10篇 |
1980年 | 8篇 |
1979年 | 15篇 |
1978年 | 7篇 |
1977年 | 8篇 |
1976年 | 8篇 |
1975年 | 6篇 |
1974年 | 10篇 |
1969年 | 6篇 |
1967年 | 5篇 |
排序方式: 共有1218条查询结果,搜索用时 15 毫秒
1.
CM Reid M. Nelson P. Beckinsale P. Ryan LMH Wing LJ Beilin MA Brown GLR Jennings CI Johnston J. Marley JJ McNeil TO Morgan J. Shaw ID Steven MJ West 《Clinical and experimental pharmacology & physiology》1997,24(5):370-373
1. The present study aimed to determine the feasibility of conducting a 5 year cardiovascular outcome trial of the treatment of 6000 elderly hypertensive patients in Australian general practices. 2. General practitioners (GPs) were invited to participate by mail and personal follow-up. Patient records were reviewed to identify subjects for a blood pressure (BP) screening programme. Blood pressure was measured on three occasions and eligible subjects were included if the average BP was 160 mmHg systolic or 90 mmHg diastolic if systolic BP was 140 mmHg. 3. Seven hundred and forty-one GPs were approached and 89 were enrolled in the study (12% of mail invites and 75% of those receiving a personal contact). In 16 practices where screening was completed, 82 000 records were reviewed to identify 4% patients eligible for screening. Twenty-two per cent of eligible subjects attended screening. Of 1938 subjects screened, 180 (9%) had BP 5=160/90 mmHg. Forty-seven percent of subjects (n = 916) were receiving antihypertensive therapy and 184 (20%) were withdrawn from therapy. One hundred and sixteen (63%) of these subjects had BP return to study entry levels within 6 weeks. Fifty-seven newly diagnosed and 81 previously treated subjects were randomized (7% of the screened population). 4. Based on the high participation rate of GPs, the response rate of patients to attend a BP screening programme and the 7% randomization to screening ratio for entry into the study, the ANBP2 pilot study has demonstrated that it is feasible to recruit subjects from Australian general practices to a cardiovascular outcome trial. 相似文献
2.
The AMPA receptor potentiator LY404187 increases cerebral glucose utilization and c-fos expression in the rat. 总被引:3,自引:0,他引:3
Jill H Fowler Katherine Whalley Tracey Murray Michael J O'neill James McCulloch 《Journal of cerebral blood flow and metabolism》2004,24(10):1098-1109
AMPA receptor potentiators enhance AMPA receptor-mediated glutamatergic neurotransmission and may have therapeutic potential as cognitive enhancers or antidepressants. The anatomical basis for the action of AMPA receptor potentiators is unknown. The aim of this study was to determine the effects of the biarylpropylsulfonamide AMPA receptor potentiator, LY404187 (0.05 to 5 mg/kg subcutaneously), upon cerebral glucose utilization and c-fos expression using 14C-2-deoxglucose autoradiography and c-fos immunocytochemistry. LY404187 (0.5 mg/kg) produced significant elevations in glucose utilization in 28 of the 52 anatomical regions analyzed, which included rostral neocortical areas and the hippocampus, as well the dorsal raphe nucleus, lateral habenula, and locus coeruleus. No significant decreases in glucose utilization were observed in any region after LY404187 administration. The increases in glucose utilization with LY404187 (0.5 mg/kg) were blocked by pretreatment with the AMPA receptor antagonist LY293558 (25 mg/kg), indicating that LY404187 acts through AMPA receptor-mediated mechanisms. LY404187 (0.5 mg/kg) also produced increases in c-fos immunoreactivity in the cortex, locus coeruleus, and the dorsal raphe nucleus. These studies demonstrate neuronal activation in key brain areas that are associated with memory processes and thus provide an anatomical basis for the cognitive enhancing effects of AMPA receptor potentiators. 相似文献
3.
4.
5.
The hypothesis that the release of vasopressin-associated neurophysin (hNpI) or oxytocin-associated neurophysin (hNpII) is modified by a course of electroconvulsive therapy (ECT) was tested by the measurement of serum neurophysins before and after the first and last ECTs given to 17 unipolar depressed patients. Neither basal nor ECT-induced neurophysin release changed between the first and last ECTs. Data from the present study were combined with data from a previous published study to provide a sample of 29 unipolar depressed patients. In this extended sample, the release of hNpII after the first ECT was significantly correlated with improvement in symptoms of depression over a course of ECT as measured by the Hamilton Rating Scale for Depression and the Montgomery-Asberg Depression Rating Scale. 相似文献
6.
We assessed the feasibility and psychometric properties of two commonly used health status questionnaires in Parkinson's disease (PD): the generic Nottingham Health Profile (NHP) and the disease-specific 39-item Parkinson's disease Questionnaire (PDQ-39), from a cross-sectional postal survey of PD patients (N = 81), using traditional and Rasch measurement methodologies. Overall response rate was 88%. Both questionnaires were found feasible, although the NHP performed less well. The PDQ-39 had fewer floor effects and was better able to separate respondents into distinct groups than the NHP, whereas the latter exhibited less ambiguous dimensionality and better targeting of respondents with non-extreme scores. Reliability and validity indices were similar, and potential differential item functioning by age and gender groups was found for both questionnaires. PDQ-39 response alternatives indicated ambiguity. With few exceptions, questionnaire scales were unable to meet recommended standards fully. While preliminary, this study illustrates the need for thorough evaluation of outcome measures and has implications beyond the questionnaires used here. Although promising, both questionnaires warrant further developmental work and stronger support of measurement validity before they could be considered fully suitable for valid use in PD, in particular in earlier stages of the disease. 相似文献
7.
8.
BACKGROUND: The recent introduction of urea sensors for dialysis monitoring
has made possible new approaches to urea kinetic modelling. In this study
we show how the equilibrated postdialysis urea concentration (Ceq) and Kt/V
corrected for double-pool urea kinetics (Kt/Vdp) can be accurately
determined using an on-line sensor providing a continuous measure of blood
water urea. A modification of the Smye constant volume double-pool theory
led to the following equations for Ceq and Kt/Vdp [formula: see text] where
Cpre is the blood concentration measured at the start of dialysis, t is the
length of the dialysis session (in min) and S(ex) is the constant slope of
the blood urea logarithm concentration decline following development of the
intercompartmental urea concentration gradient in the first 30-60 min of
dialysis. METHODS: These equations were tested in 11 patients undergoing
165-240 min of paired filtration dialysis with continuous monitoring of
blood urea concentration. Cpre was determined as the plateau concentration
during a preliminary period of 15-20 min of slow isolated ultrafiltration.
S(ex) was accurately determined from linear regression applied to the urea
sensor data from the 80-min point to the end of dialysis. RESULTS: Ceq and
Kt/Vdp determined from the above equations compared closely to values
determined from 25-40 min of urea rebound monitoring with the urea sensor:
10.6 +/- 3.0 versus 10.8 +/- 2.7 mmol/l (mean +/- SD) for Ceq and 1.21 +/-
0.24 versus 1.18 +/- 0.20 for Kt/Vdp, compared to single-pool values of
Kt/V = 1.34 +/- 0.23. CONCLUSION: This technique may be readily programmed
into on-line urea monitors to provide current and extrapolated values of
Ceq and Kt/Vdp from about the first hour of dialysis.
相似文献
9.
10.