全文获取类型
收费全文 | 1355篇 |
免费 | 98篇 |
专业分类
耳鼻咽喉 | 8篇 |
儿科学 | 42篇 |
妇产科学 | 46篇 |
基础医学 | 276篇 |
口腔科学 | 13篇 |
临床医学 | 165篇 |
内科学 | 234篇 |
皮肤病学 | 23篇 |
神经病学 | 132篇 |
特种医学 | 56篇 |
外科学 | 155篇 |
综合类 | 12篇 |
一般理论 | 2篇 |
预防医学 | 137篇 |
眼科学 | 6篇 |
药学 | 43篇 |
中国医学 | 1篇 |
肿瘤学 | 102篇 |
出版年
2023年 | 10篇 |
2021年 | 17篇 |
2020年 | 19篇 |
2019年 | 30篇 |
2018年 | 25篇 |
2017年 | 30篇 |
2016年 | 21篇 |
2015年 | 28篇 |
2014年 | 36篇 |
2013年 | 46篇 |
2012年 | 93篇 |
2011年 | 79篇 |
2010年 | 36篇 |
2009年 | 40篇 |
2008年 | 62篇 |
2007年 | 77篇 |
2006年 | 77篇 |
2005年 | 97篇 |
2004年 | 65篇 |
2003年 | 56篇 |
2002年 | 63篇 |
2001年 | 32篇 |
2000年 | 35篇 |
1999年 | 25篇 |
1998年 | 24篇 |
1997年 | 11篇 |
1996年 | 8篇 |
1995年 | 14篇 |
1994年 | 7篇 |
1993年 | 9篇 |
1992年 | 18篇 |
1991年 | 12篇 |
1990年 | 18篇 |
1989年 | 16篇 |
1988年 | 16篇 |
1987年 | 20篇 |
1986年 | 17篇 |
1985年 | 12篇 |
1984年 | 18篇 |
1983年 | 12篇 |
1982年 | 10篇 |
1981年 | 5篇 |
1977年 | 6篇 |
1976年 | 6篇 |
1975年 | 9篇 |
1973年 | 10篇 |
1971年 | 7篇 |
1970年 | 10篇 |
1969年 | 7篇 |
1968年 | 5篇 |
排序方式: 共有1453条查询结果,搜索用时 15 毫秒
1.
Bernd Huber Ines Hauser Verena Horstmann Gabi Jokeit Sylvia Liem Theodor May Thomas Meinert Enrique Robertson Heide Schorlemmer Wolfgang Wagner Michael Seidel 《Seizure》2007,16(1):35-42
This study was designed to describe the course of epilepsy (in terms of seizure frequency) and to assess the variables (antiepileptic therapy regimens and others) correlated to improvement. Seizure frequency (categories: seizure free, more than one seizure/year, monthly seizures, weekly seizures and daily seizures) and antiepileptic medication were retrospectively compared between 1992 and 2002 in a large cohort of 550 inpatients with chronic epilepsy and different degrees of intellectual disability or multiple handicaps. RESULTS: Seizure frequency decreased significantly (p<0.001). 218 of the 394 patients (55.3%) not seizure free in 1992 improved (changed into a better frequency category). The improvement rate was marginally higher in patients who had undergone a medication change (p=0.08). A high seizure frequency in 1992 (p=0.016) and older age (p=0.006), but not epilepsy syndrome or degree of intellectual disability, were predictors for improvement (stepwise logistic regression analysis). 56.4% of the improved patients were on combinations of two AEDs (17.4%, monotherapy; 20.2%, triple therapy). The most frequent therapy regimens in the improved patients were lamotrigine/valproate (48 patients), carbamazepine/phenobarbital (21) and carbamazepine only (19). Lamotrigine/valproate was effective in all kinds of epileptic syndromes. Most patients on lamotrigine had serum concentrations above 10microg/ml, approximately one half had dosages above 200mg/day. The rate of seizure freedom increased from 28.4 to 37.6%. The 84% of the patients seizure free in 1992 remained seizure free. Predictors for seizure freedom in 2002 were higher age (stepwise logistic regression, p<0.0005) and seizure freedom in 1992 (p<0.0005). CONCLUSIONS: Substantial improvement can be achieved even in intellectually disabled patients with chronic epilepsy. Although the rate of seizure freedom is reduced in comparison with a non-ID population, once seizure freedom has been achieved it is most likely to continue. For a majority of this patient population, monotherapy may not be sufficient. Lamotrigine/valproate appears to be a major therapeutic innovation. 相似文献
2.
R. J. Bosma A. J. Kwakernaak J. J. Homan van der Heide P. E. de Jong G. J. Navis 《American journal of transplantation》2007,7(3):645-652
Obesity is a risk factor for renal graft loss. Higher body mass index (BMI) in native kidneys is associated with glomerular hyperfiltration. Whether higher BMI in renal transplants is associated with hyperfiltration is unknown. We investigated the impact of BMI on renal hemodynamics 1 year post-transplant. We analyzed glomerular filtration rate (GFR, (125)I-iothalamate) and effective renal plasma flow (ERPF, (131)I-hippurate) in 838 kidney transplants. Data were analyzed for all patients and for the subpopulation without diabetes. Long-term impact of BMI and renal hemodynamics were explored by Cox-regression. With higher BMI GFR and filtration fraction (FF) increased significantly. Multivariate analysis supported impact of BMI on GFR (adjusted r(2) of the model 0.275) and FF (adjusted r(2) of the model 0.158). This association was not explained by diabetes mellitus. On Cox-regression analysis, lower GFR and higher FF were independent determinants of overall graft loss and graft loss by patient mortality. Lower GFR and higher BMI were determinants of death-censored graft loss, with borderline contribution of higher FF. In renal transplants higher BMI is independently associated with higher GFR and FF one year posttransplant, suggesting glomerular hyperfiltration with altered afferent-efferent balance. Mechanisms underlying the long-term prognostic impact of hyperfiltration deserve further exploration. 相似文献
3.
4.
5.
Hilmar H. Bijma Agnes van der Heide Hajo I. J. Wildschut 《European Clinics in Obstetrics and Gynaecology》2007,3(2):89-95
During the last few decades, the use of ultrasonography for the detection of fetal abnormalities has become widespread in
many industrialised countries. This resulted in a shift in timing of the diagnosis of congenital abnormalities in infants
from the neonatal period to the prenatal period. This has major implications for both clinicians and the couples involved.
In case of ultrasound diagnosis of fetal anomaly, there are several options for the obstetric management, ranging from standard
care to non-aggressive care and termination of pregnancy. This essay explores the context of both clinical and parental decision
making after ultrasound diagnosis of fetal abnormality, with emphasis on the Dutch situation. While normal findings at ultrasound
examination have strong beneficial psychological effects on the pregnant woman and her partner, the couple is often ill prepared
for bad news about the health of their unborn child in the case of abnormal findings. This is, in particular, true in settings
where ultrasonography for the detection of fetal abnormalities is offered as an integral part of antenatal care without appropriate
counselling. An important question is to what extent the couple should be supported in decision making when a fetal abnormality
is diagnosed. In this context, the parental perception of having a choice varies markedly. When parents consider end-of-life
decisions, they experience both ambivalent and emotional feelings. On the one hand, they are committed to their pregnancy,
while on the other hand, they want to protect their child, themselves and the family from the burden of severe disability.
These complex parental reactions have implications for the counselling strategy.
相似文献
Hajo I. J. WildschutEmail: |
6.
Microorganisms isolated from the soil and the rhizosphere of wheat plants produce growth regulating substances with effects similar to gibberellins when grown in submerse cultures. Bioassays and thin layer chromatography were used for characterization. Different plant growth regulating substances and variations in their quantity were observed among microorganisms. The amounts of gibberellin-like substances found in culture filtrates varied, in a range from 0.01 to 1.0 mg GA3 equivalents per liter. 相似文献
7.
In modern clinical practice different options for induction of labor such as oxytocin and a number of different prostaglandin preparations are available. The present contribution elucidates the different possibilities and provides information about indication, doses and potential complications of induction of labor. As with any other medical intervention, a critical risk-benefit analysis and a thorough explanation of the induction procedure should be provided to the pregnant woman. 相似文献
8.
Johannes W. G. Jacobs MD PhD Agnes van der Heide MD Johannes J. Rasker MD PhD Johannes W. J. Bijlsma MD PhD 《Patient education and counseling》1993,20(2-3):121-132
Chronic arthritis may have great impact on the patient but also on his or her family, relatives and friends. The assessment of the consequences of chronic arthritis and the effect of therapy not only in terms of physical, but also psychological and social dimensions deserves more attention. Functional ability and health status can be measured using a questionnaire or ‘instrument’, high-lighting important aspects not quantified with more traditional measurements. In this paper, arguments to apply such instruments more frequently are given. Health status instruments can be used not only to assess beneficial but also deleterious (side-)effects of therapeutic interventions. The properties are summarized of the most frequently used instruments assessing functional ability and health status. Many of these instruments have been evaluated sufficiently for validity and reliability; their sensitivity to detect change seems to be satisfactory. Therefore it is advisable to choose an internationally accepted, frequently used instrument, reflecting the area of interest. 相似文献
9.
Immunocytochemical analysis of cellular responses to BCG. 总被引:2,自引:0,他引:2
P H Nibbering G A van der Heide R van Furth 《Clinical and experimental immunology》1989,75(1):147-154
The study reported here was performed to find out whether changes in the number of mycobacteria in various organs of BCG-infected mice can be related to changes in the phenotype of monocytes, macrophages and lymphocytes in the blood, various tissues, and peritoneal cavity and to the formation of granulomas in the spleen, liver and lungs. The relative amounts of various antigens on the leukocytes were assessed semi-quantitatively after immunocytochemical detection of the binding of monoclonal antibodies. Granuloma formation was determined after immunocytochemical staining of cells in sections of liver and lung tissue with a monoclonal antibody against the common leukocyte antigen and in sections of the spleen with a monoclonal antibody against the Mac-2 antigen. The results showed that during the first week of infection the number of BCG in spleen, liver and lungs declined considerably. Multiplication of mycobacteria during the second week of infection was associated with decreased expression of antigen F4/80 and increased expression of Ia antigen and Mac-2 antigen by blood monocytes and macrophages. Reduction of the numbers of BCG in the spleen and liver during the third week after i.v. injection of BCG and in lungs during the fourth week of the infection was found to be correlated with the degree of granuloma formation in these organs. After intravenous injection of killed BCG no changes were observed in the phenotype of monocytes and the macrophages in spleen, liver, lungs and peritoneal cavity. These mice showed considerably less granuloma formation than BCG-infected mice. The present results indicate that live but not killed mycobacteria induce macrophage activation. 相似文献
10.
Heide Hörtnagl 《Neuroscience》1976,1(1):9-IN3
The protein and lipid composition of the membrane of the chromaffin granule has been compared with that of an endoplasmic reticulum fraction isolated from bovine adrenal medulla. The endoplasmic reticulum was purified by centrifugation of a microsomal fraction in sucrose and Ficoll density gradients. Only insignificant amounts of chromomembrin B, dopamine β-hydroxylase and cytochrome b559, which are characteristic protein components of the chromaffin granule membrane, were present in the endoplasmic reticulum fraction; whereas glucose-6-phosphatase and galactosyltransferase, marker enzymes of membranes of endoplasmic reticulum and Golgi complex respectively, were absent from the membranes of chromaffin granules. The lipid composition of the two types of membranes varies in the relative amounts of lysolecithin, lecithin and sphingomyelin and in the molar ratio of cholesterol to phospholipid. Lysolecithin, which is a major phospholipid of the chromaffin granule membrane, is virtually absent from membranes of the endoplasmic reticulum. Different protein patterns were obtained when these two membrane fractions were solubilized with detergent and subjected to polyacrylamide gel electrophoresis.It is concluded that membranes of the endoplasmic reticulum and those of the chromaffin granules are basically different and therefore that the transport of secretory proteins from their site of synthesis to their site of storage occurs, in the chromaffin cell, by a mechanism that does not involve a mixing of the participating membranes. 相似文献