全文获取类型
收费全文 | 1562篇 |
免费 | 98篇 |
国内免费 | 49篇 |
专业分类
耳鼻咽喉 | 27篇 |
儿科学 | 55篇 |
妇产科学 | 4篇 |
基础医学 | 164篇 |
口腔科学 | 12篇 |
临床医学 | 213篇 |
内科学 | 359篇 |
皮肤病学 | 26篇 |
神经病学 | 134篇 |
特种医学 | 179篇 |
外科学 | 120篇 |
综合类 | 29篇 |
预防医学 | 184篇 |
眼科学 | 12篇 |
药学 | 116篇 |
中国医学 | 7篇 |
肿瘤学 | 68篇 |
出版年
2022年 | 6篇 |
2021年 | 18篇 |
2020年 | 13篇 |
2019年 | 17篇 |
2018年 | 23篇 |
2017年 | 28篇 |
2016年 | 20篇 |
2015年 | 29篇 |
2014年 | 37篇 |
2013年 | 54篇 |
2012年 | 56篇 |
2011年 | 50篇 |
2010年 | 58篇 |
2009年 | 61篇 |
2008年 | 41篇 |
2007年 | 80篇 |
2006年 | 45篇 |
2005年 | 49篇 |
2004年 | 39篇 |
2003年 | 48篇 |
2002年 | 53篇 |
2001年 | 39篇 |
2000年 | 35篇 |
1999年 | 32篇 |
1998年 | 55篇 |
1997年 | 50篇 |
1996年 | 58篇 |
1995年 | 38篇 |
1994年 | 37篇 |
1993年 | 24篇 |
1992年 | 29篇 |
1991年 | 27篇 |
1990年 | 21篇 |
1989年 | 52篇 |
1988年 | 48篇 |
1987年 | 48篇 |
1986年 | 46篇 |
1985年 | 30篇 |
1984年 | 28篇 |
1983年 | 20篇 |
1982年 | 27篇 |
1981年 | 19篇 |
1980年 | 16篇 |
1979年 | 11篇 |
1978年 | 10篇 |
1977年 | 10篇 |
1976年 | 13篇 |
1975年 | 16篇 |
1971年 | 4篇 |
1969年 | 5篇 |
排序方式: 共有1709条查询结果,搜索用时 198 毫秒
1.
Sexuality and Disability - 相似文献
2.
Sexuality and Disability - 相似文献
3.
HJ Aubin S Tilikete C Laureaux HT Nguyen Hac MC Roullet-Volmi S Troupel D Barrucand 《European psychiatry》1995,10(8)
The aim of this study was to assess alcoholic inpatients' smoking and coffee intake variation following withdrawal. Only moderate smokers (less than 30 cigarettes/day) showed a significant increase of cigarette consumption after alcohol withdrawal. However, their urinary cotinine level did not vary, suggesting a behavioral, and not biological, compensation through smoking following alcohol withdrawal. Heavy smokers (30 cigarettes/day or more) showed no significant clinical or biological variation of smoking behavior. Coffee consumption increased after alcohol withdrawal in all patients, irrespective of smoking habits. 相似文献
4.
Previous studies from this Laboratory have revealed few significant age-related changes in either hepatic microsomal cytochrome
P450 content or NADPH-cytochrome P450 reductase activity, prompting the suggestion that the nearly ubiquitous age-associated decline in the hepatic metabolism
of xenobiotics by the mixed-function oxidases is a result of alterations in the lipid matrix in which the macromolecular components
are organized. In order to examine this postulate, the membrane microenvironment surrounding hepatic microsomal cytochrome
P450 was enzymatically digested with snake venom phospholipase A2, and the kinetics of conversion of cytochrome P450 to cytochrome P420 determined for preparations obtained from rats of varying age. There were no significant differences in the kinetics of conversion
of cytochrome P450 to cytochrome P420, suggesting that there are no significant age-related changes in the lipid microenvironment immediately adjacent to cytochrome
P450. However, there was a slight difference, independent of age, in the rate of conversion of cytochrome P450 to cytochrome P420 between smooth and rough microsomes. The results are discussed in terms of general experimental approaches toward understanding
drug metabolism in senescent organisms. 相似文献
5.
BACKGROUND: A simple, rapid, inexpensive method for measuring the flow in a
patient's vascular access would permit routine monitoring during
haemodialysis, and hence provide information of access graft deterioration
sufficiently early to increase the success of minimally invasive remedial
procedures. This paper reports the validation of such a method in animals.
METHODS: A PTFE graft was implanted in sheep between the carotid artery and
the jugular vein. While the sheep was under general anaesthesia and on an
haemodialysis circuit, ultrasound velocity in its blood was perturbed by
the injection of a 5-10 ml bolus of isotonic NaCl. The pump tubing flow was
measured by a transit-time blood flow meter. This flow was combined with
the areas of perturbation generated by the injection before and after
mixing in the access flow to estimate graft flow. The calculated graft flow
was compared to flow measured directly by a transit-time probe on the same
carotid artery. RESULTS: Over a 10-fold range, 120-1260 ml/min, graft flow
measured by ultrasound velocity dilution agreed well with graft flow
measured directly with a scatter of 76 ml/min about the regression line.
CONCLUSION: Ultrasound velocity dilution provides a method for measuring
flow in the graft accurate enough for clinical evaluation of patients on
dialysis.
相似文献
6.
Robert M. Post Andrew M. Speer Christopher J. Hough Guoqiang Xing 《Annals of clinical psychiatry》2003,15(2):85-94
Many findings implicating prefrontal cortical and limbic areas of the brain and endocrine systems in the neuropathology and pathophysiology of bipolar illness have greatly increased our understanding of the neurobiology of the illness. New imaging techniques such as PET, MRI, SPECT, and MRS have detailed more evidence of specific regional alterations in the brains of bipolar patients than was thought possible just 20 years ago. These methods are beginning to be used to help predict response to treatment. Examining the mechanisms of action of mood stabilizers (such as lithium, carbamazepine, and valproate) has provided clues to potential underlying neurobiological abnormalities in the illness. Recent studies of postmortem brain tissue have begun to confirm prefrontal cortical and limbic neurochemical and microstructural alterations in patients with bipolar illness compared with controls. It is postulated that it is the balance between primary pathological versus secondary adaptive alterations in gene expression in the illness and their enhancement or dampening by pharmacotherapy, that may determine the episodic course of mood fluctuations and remissions. Further examination of the pathophysiology and neurobiology of bipolar illness should lead to both more effective treatments and, potentially, secondary and even primary episode prevention. 相似文献
7.
T L Yarboro B Harry E Hough K Moyers T Muscarella 《Journal of the National Medical Association》1991,83(5):409-414
Perhaps the most significant link in achieving the nation's immunization objectives is the extent of parental knowledge. Admittedly, this is a weak link. The 1990 federal objectives calling for an official format using common guidelines for completion of immunizations, though well-conceived, has not been used exclusively by health care givers. The lack of accord has permitted the proliferation of many different immunization records that are not only confusing to parents, but also to health care providers at times. A standard national immunization record could be an essential element in strengthening the weak link of parental knowledge of immunizations and stressing the importance of preserving such a record for a lifetime. 相似文献
8.
Antagonism of the histamine (H2) receptor reduces antinociception induced by naloxone-resistant foot-shock, naloxone-sensitive foot-shock, and morphine with a rank-order potency similar to their H2 antagonism. The antimetabolic glucose analog 2-deoxy-D-glucose (2DG) produces antinociceptive and hyperphagic responses that dissociate from each other and are in part mediated by opioid systems. The present study determined the effects of the brain-penetrating H2 receptor antagonist zolantidine (ZOL) on 2DG antinociception on the tail-flick and jump tests, as well as on 2DG hyperphagia, in rats. ZOL (0.01-1 mg/kg) potentiated the antinociceptive responses induced by a moderate (450 mg/kg) dose of 2DG, but had lesser effects upon antinociception induced by a lower (100 mg/kg) 2DG dose. ZOL itself slightly increased jump thresholds, but not tail-flick latencies. Combinations of ZOL and 2DG produced supraadditive antinociception, even though ZOL failed to significantly shift the 2DG dose-response curve to the left. In contrast, ZOL failed to alter basal intake or 2DG hyperphagia, supporting previous evidence implicating the H1 but not the H2 receptor in these effects. These results further dissociate the antinociceptive and hyperphagic effects of 2DG, and also support previous results indicating both pro- and antinociceptive roles for H2 receptors. 相似文献
9.
M Kaplan HJ Vreman C Hammerman C Leiter B Rudensky MG MacDonald DK Stevenson 《Acta paediatrica (Oslo, Norway : 1992)》1998,87(4):455-457
The incidence (%) of hyperbilirubinemia (serum bilirubin ≥257 μmol/l) was similar in neonates with a combination of ABO incompatibility and glucose-6-phosphate dehydrogenase (G-6-PD) deficiency (45%), with ABO incompatibility (54%) or G-6-PD deficiency (37%), alone (ns). Carboxyhemoglobin values, corrected for inspired CO, were similarly elevated in all three groups (0.87 ± 0.32%, 0.82 ± 0.29%, 0.76 ± 0.18%, respectively, ns), but correlated with bilirubin only in those with ABO incompatibility alone. ABO-incompatible/G-6-PD-deficient neonates, compared with those with either condition alone, are not at increased risk for hemolysis or hyperbilirubinemia. 相似文献
10.
Acculturation and the probability of use of health services by Mexican Americans. 总被引:11,自引:1,他引:10 下载免费PDF全文
How does level of acculturation affect the probability that Mexican Americans use general health, mental health, and human social services? We studied this question using data from a general population sample of Mexican Americans (N = 1,055). Data were elicited in face-to-face interviews. After controlling for sociodemographic and economic factors, health status, and insurance coverage, Mexican Americans who were less acculturated had significantly lower probabilities of an outpatient medical visit for physical health problems and of a visit to a mental health specialist or human service provider for emotional problems. The less acculturated with good perceived general health were especially unlikely to receive outpatient medical care. Having Medicaid coverage was associated with a larger increase in the probability of an inpatient medical admission for the more acculturated than for the less acculturated. Other individual characteristics had generally similar effects on use of medical and mental health services for both the more and the less acculturated Mexican Americans. 相似文献