全文获取类型
收费全文 | 781篇 |
免费 | 67篇 |
国内免费 | 16篇 |
专业分类
耳鼻咽喉 | 4篇 |
儿科学 | 38篇 |
妇产科学 | 16篇 |
基础医学 | 171篇 |
口腔科学 | 8篇 |
临床医学 | 66篇 |
内科学 | 138篇 |
皮肤病学 | 19篇 |
神经病学 | 39篇 |
特种医学 | 43篇 |
外科学 | 78篇 |
综合类 | 37篇 |
预防医学 | 67篇 |
眼科学 | 6篇 |
药学 | 100篇 |
中国医学 | 1篇 |
肿瘤学 | 33篇 |
出版年
2021年 | 5篇 |
2019年 | 6篇 |
2018年 | 11篇 |
2017年 | 11篇 |
2016年 | 11篇 |
2015年 | 12篇 |
2014年 | 18篇 |
2013年 | 30篇 |
2012年 | 26篇 |
2011年 | 27篇 |
2010年 | 28篇 |
2009年 | 30篇 |
2008年 | 24篇 |
2007年 | 27篇 |
2006年 | 26篇 |
2005年 | 28篇 |
2004年 | 17篇 |
2003年 | 18篇 |
2002年 | 25篇 |
2001年 | 26篇 |
2000年 | 21篇 |
1999年 | 28篇 |
1998年 | 41篇 |
1997年 | 30篇 |
1996年 | 19篇 |
1995年 | 18篇 |
1994年 | 19篇 |
1993年 | 18篇 |
1992年 | 15篇 |
1991年 | 21篇 |
1990年 | 23篇 |
1989年 | 20篇 |
1988年 | 17篇 |
1987年 | 17篇 |
1986年 | 12篇 |
1985年 | 17篇 |
1984年 | 8篇 |
1983年 | 11篇 |
1982年 | 9篇 |
1981年 | 12篇 |
1980年 | 7篇 |
1979年 | 9篇 |
1978年 | 9篇 |
1977年 | 7篇 |
1976年 | 7篇 |
1975年 | 7篇 |
1974年 | 4篇 |
1973年 | 6篇 |
1971年 | 5篇 |
1970年 | 4篇 |
排序方式: 共有864条查询结果,搜索用时 15 毫秒
1.
2.
3.
B. J. M. Vlaminckx W. van Pelt J. F. P. Schellekens 《Clinical microbiology and infection》2005,11(7):564-568
A nationwide laboratory-based surveillance system for invasive group A streptococcal (GAS) infections was conducted in The Netherlands from March 1992 until December 2003. Until 1996, all isolates submitted were evaluated clinically and demographically. During this period there was a transition from passive to active surveillance for some of the participating laboratories, corresponding to a national coverage of 50%. During active surveillance, participating laboratories submitted twice as many isolates from invasive GAS disease, whereas the relative submission of isolates representing very severe manifestations (toxic shock-like syndrome, fatality) did not increase. From 1997 onwards, invasiveness was defined solely on the basis of source of isolation (without clinical evaluation). During the period of microbiological and clinical evaluation, microbiological evaluation alone was found to be specific (> 99%), but had limited sensitivity (66%). Estimation of the true rate of invasive GAS disease should be based on an active surveillance system with inclusion of both microbiological and clinical data. 相似文献
4.
The Effect of Antiepileptic Drugs on Cognition: Patient Perceived Cognitive Problems of Topiramate versus Levetiracetam in Clinical Practice 总被引:1,自引:0,他引:1
Hans-Peter R. Bootsma †Albert P. Aldenkamp Leonie Diepman Jacques Hulsman Danielle Lambrechts Loes Leenen Marian Majoie Ad Schellekens †Marc de Krom 《Epilepsia》2006,47(S2):24-27
Summary: Introduction: Neurocognitive complaints may interfere with long-term antiepileptic drug (AED) treatment and are an important issue in clinical practice. Most data about drug-induced cognitive problems are derived from highly controlled short-term clinical trials. We analyzed such cognitive complaints for the two most commonly used AEDs in a clinical setting using patient perceived problems as primary outcome measure.
Method: All patients of the epilepsy center Kempenhaeghe that received topiramate (TPM) or levetiracetam (LEV) from the introduction to mid 2004 were analyzed using a medical information system, an automated medical file. Patients were analyzed after 6, 12, and 18 months of treatment.
Results: Four hundred and two patients used either TPM (n = 260) or LEV (n = 142); 18 months retention showed a statistically significant difference, revealing 15% more patients that continued LEV compared to TPM: 18 months retention 46% for TPM and 61% for LEV [F (1.400) = 3.313, p = 0.043]. Neurocognitive complaints accounted for a significant number of drug discontinuations and especially the high frequency of neurocognitive complaints in the first period of TPM treatment appeared to be significant different from LEV [F(2,547) = 3.192, p = 0.042]. In the remaining patients, the difference in neurocognitive complaints was not statistically significant.
Conclusion: cognitive complaints are common in TPM treatment and frequently lead to drug withdrawal. The impact of LEV on cognitive function is only mild. This leads to a much higher (15%) drug discontinuation rate for TPM compared to LEV. 相似文献
Method: All patients of the epilepsy center Kempenhaeghe that received topiramate (TPM) or levetiracetam (LEV) from the introduction to mid 2004 were analyzed using a medical information system, an automated medical file. Patients were analyzed after 6, 12, and 18 months of treatment.
Results: Four hundred and two patients used either TPM (n = 260) or LEV (n = 142); 18 months retention showed a statistically significant difference, revealing 15% more patients that continued LEV compared to TPM: 18 months retention 46% for TPM and 61% for LEV [F (1.400) = 3.313, p = 0.043]. Neurocognitive complaints accounted for a significant number of drug discontinuations and especially the high frequency of neurocognitive complaints in the first period of TPM treatment appeared to be significant different from LEV [F(2,547) = 3.192, p = 0.042]. In the remaining patients, the difference in neurocognitive complaints was not statistically significant.
Conclusion: cognitive complaints are common in TPM treatment and frequently lead to drug withdrawal. The impact of LEV on cognitive function is only mild. This leads to a much higher (15%) drug discontinuation rate for TPM compared to LEV. 相似文献
5.
AP de Moraes† ÉÂG de Arruda† MAV Vitoriano† MO de Moraes Filho‡ FÂF Bezerra‡ E de Magalhães Holanda§ MEA de Moraes‡ 《Journal of the European Academy of Dermatology and Venereology》2007,21(5):596-601
BACKGROUND: Seborrhoeic dermatitis (SD) is a common dermatosis in human immunodeficiency virus (HIV)-positive patients, many of whom do not respond satisfactorily to conventional topical treatments such as corticosteroids and antifungals. OBJECTIVE: A pilot study to investigate the efficacy and tolerability of pimecrolimus cream 1% in HIV-positive patients with facial SD. METHODS: In a single-centre study, 21 HIV-infected patients with mild to severe SD were treated twice daily with pimecrolimus cream 1% for 14 days. Thereafter, treatment was discontinued and patients followed up for 5 weeks. Skin involvement at baseline and on days 7, 14, 21, 35 and 49 was assessed using a four-point clinical score and digital photography. MAIN OUTCOME MEASURES: Efficacy and safety of pimecrolimus cream 1% treatment and incidence of relapse in the follow-up phase. Results Marked improvement was seen in clinical parameters at day 7, with >or= 90% patients clear of symptoms at day 14. Relapse was observed at day 35 but signs were milder than at baseline. All patients responded to therapy, despite their immunological status. Pimecrolimus did not alter CD4(+) and CD8(+) T-cell counts or viral load during the treatment period. CONCLUSION: Pimecrolimus cream represents a new, effective therapeutic option for facial SD in HIV patients. 相似文献
6.
7.
Evaluation of the immunosuppressive effects of cyclophosphamide in patients with multiple sclerosis.
下载免费PDF全文
![点击此处可从《Clinical and experimental immunology》网站下载免费的PDF全文](/ch/ext_images/free.gif)
R J ten Berge H K van Walbeek P T Schellekens 《Clinical and experimental immunology》1982,50(3):495-502
In a group of eight patients suffering from clinically definite multiple sclerosis, we studied the effects of treatment with cyclophosphamide on the immune reactivity in vitro and in vivo. The results are compared with those obtained in a control group consisting of eight patients who received no drug therapy and who were matched with the former group for age, sex and severity of disease. The results indicate that therapy with cyclophosphamide at a mean dose of 100 mg/day induces a profound lymphocytopenia in peripheral blood involving both T and B cells. Serum levels of immunoglobulins as well as primary and secondary antibody responses were depressed. In tests with standardized cell numbers, proliferative responses of lymphocytes in vitro and cytotoxic T cell function remained normal, whereas K and NK cell activities were diminished. Secondary cellular immune responses in vivo remained intact; however, the primary cellular immune response in vivo was markedly depressed. From these data, it is concluded that therapy with cyclophosphamide in man mainly affects humoral immune functions, but also cellular immunity, although to a lesser extent. 相似文献
8.
In-vitro maturation of human germinal vesicle stage oocytes: role of cumulus cells and epidermal growth factor in the culture medium 总被引:21,自引:6,他引:21
Goud PT; Goud AP; Qian C; Laverge H; Van der Elst J; De Sutter P; Dhont M 《Human reproduction (Oxford, England)》1998,13(6):1638-1644
In-vitro maturation (IVM) of oocytes is a promising technique to reduce the
costs and avert the side-effects of gonadotrophin stimulation for in-vitro
fertilization (IVF). The pregnancy rates from oocytes matured in vitro are
much lower than those of in-vivo stimulation cycles indicating that
optimization of IVM remains a challenge. Therefore, we investigated the
effect of supplementation of the medium with gonadotrophins, oestradiol and
epidermal growth factor (EGF) and the effect of retaining or removing the
cumulus cells on nuclear and cytoplasmic maturation of immature oocytes.
Human germinal vesicle (GV) oocytes obtained after gonadotrophin
stimulation for intracytoplasmic sperm injection (ICSI) were cultured in a
complex defined medium either supplemented with gonadotrophins, oestradiol
and physiological concentrations of EGF (2 ng/ml) or gonadotrophins and
oestradiol alone. The cumulus cells were either removed or kept intact. In
GV stage oocytes cultured without cumulus (group I) significantly more
oocytes reached the metaphase II (MII) stage at 30 h in media supplemented
with EGF (64.3 versus 33.9%, P < 0.003). For oocytes cultured with
intact cumulus (group II), more oocytes reached MII at 30 h than in group
I, but there was no difference in medium with or without EGF
supplementation (81.8 and 79.8% respectively). Cytoplasmic maturation of
MII oocytes was judged from their capability to activate and fertilize
after ICSI. In group I, the rates of activation and normal fertilization
were similar. However, in group II, significantly more oocytes underwent
normal fertilization in the EGF-supplemented than the unsupplemented group
(71.7 versus 45.6%, P < 0.05). The cleavage rates of the fertilized
oocytes were similar in the sibling oocyte subgroups cultured with or
without EGF supplementation, but the overall cleavage rates were higher in
cumulus-intact compared to cumulus-denuded oocytes (88.9 versus 47.8%, P
< 0.001). Thus, supplementation of the maturation medium with EGF and
maintenance of the cumulus during culture improve the nuclear and
cytoplasmic maturation of human oocytes in vitro.
相似文献
9.
The effects of co-culture with human fibroblasts on human embryo development in vitro and implantation 总被引:5,自引:0,他引:5
Wetzels AM; Bastiaans BA; Hendriks JC; Goverde HJ; Punt-van der Zalm AP; Verbeet JG; Braat DD 《Human reproduction (Oxford, England)》1998,13(5):1325-1330
In a human in-vitro fertilization (IVF) programme, the effect of co-
culture of embryos with human fibroblasts was evaluated with respect to
pregnancy rate and embryo development. Patients were included in the study
after giving informed written consent. The IVF treatments were randomly
assigned by stratification of both age (<36 versus > or =36 years)
and previous IVF attempts (yes versus no). After fertilization was
established, the zygotes were transferred to a 4-well dish with or without
fibroblasts and cultured for 2 days. On the third day after ovum pick-up
(OPU), cell number and quality [5 (good) to 1 (poor)] of the embryos were
scored and a maximum of three embryos was transferred. Supernumerary
embryos of good quality were cryopreserved. The design of this study was a
group sequential trial with the objective of detecting differences between
pregnancy rates following IVF with conventional incubation or incubation in
co-culture with fibroblasts. This design included one evaluation at
half-way data collection. In the study, 148 patients had an OPU, of whom 77
were allocated to the co-culture group. There was no statistically
significant difference in pregnancy rate, cell number and embryo quality
between the two groups. The ongoing pregnancy rate per embryo transfer was
27% in co-culture and 30% in the conventional culture group. The
implantation rates per transferred embryo were 17 and 18% respectively.
Using a multivariate logistic regression model for the probability of
ongoing pregnancies, the odds ratio of co-culture, adjusted for age and
previous IVF attempts, was not statistically significant. In conclusion,
co-culture with human fibroblasts does not contribute to an improvement of
embryo quality nor to a higher pregnancy rate after IVF in an unselected
group of patients.
相似文献
10.
The UTX gene escapes X inactivation in mice and humans 总被引:7,自引:3,他引:7
Greenfield A; Carrel L; Pennisi D; Philippe C; Quaderi N; Siggers P; Steiner K; Tam PP; Monaco AP; Willard HF; Koopman P 《Human molecular genetics》1998,7(4):737-742
We recently have identified a ubiquitously transcribed mouse Y chromosome
gene, Uty , which encodes a tetratricopeptide repeat (TPR) protein. A
peptide derived from the UTY protein confers H-Y antigenicity on male
cells. Here we report the characterization of a widely transcribed X-linked
homologue of Uty , called Utx , which maps to the proximal region of the
mouse X chromosome and which detects a human X-linked homologue at Xp11.2.
Given that Uty is ubiquitously transcribed, we assayed for Utx expression
from the inactive X chromosome (Xi) in mice and found that Utx escapes X
chromosome inactivation. Only Smcx and the pseudoautosomal Sts gene on the
mouse X chromosome have been reported previously to escape inactivation.
The human UTX gene was also found to be expressed from Xi. We discuss the
significance of these data for our understanding of dosage compensation of
X-Y homologous genes in humans and mice.
相似文献