全文获取类型
收费全文 | 1358篇 |
免费 | 104篇 |
国内免费 | 4篇 |
专业分类
耳鼻咽喉 | 10篇 |
儿科学 | 47篇 |
妇产科学 | 28篇 |
基础医学 | 152篇 |
口腔科学 | 17篇 |
临床医学 | 156篇 |
内科学 | 256篇 |
皮肤病学 | 13篇 |
神经病学 | 146篇 |
特种医学 | 57篇 |
外科学 | 112篇 |
综合类 | 17篇 |
一般理论 | 1篇 |
预防医学 | 204篇 |
眼科学 | 20篇 |
药学 | 69篇 |
肿瘤学 | 161篇 |
出版年
2023年 | 20篇 |
2022年 | 40篇 |
2021年 | 65篇 |
2020年 | 33篇 |
2019年 | 50篇 |
2018年 | 57篇 |
2017年 | 33篇 |
2016年 | 40篇 |
2015年 | 35篇 |
2014年 | 59篇 |
2013年 | 52篇 |
2012年 | 108篇 |
2011年 | 107篇 |
2010年 | 58篇 |
2009年 | 44篇 |
2008年 | 83篇 |
2007年 | 60篇 |
2006年 | 73篇 |
2005年 | 55篇 |
2004年 | 56篇 |
2003年 | 50篇 |
2002年 | 36篇 |
2001年 | 23篇 |
2000年 | 20篇 |
1999年 | 16篇 |
1998年 | 13篇 |
1997年 | 10篇 |
1996年 | 12篇 |
1995年 | 12篇 |
1994年 | 9篇 |
1993年 | 10篇 |
1992年 | 12篇 |
1991年 | 4篇 |
1990年 | 9篇 |
1989年 | 7篇 |
1988年 | 10篇 |
1983年 | 5篇 |
1982年 | 5篇 |
1979年 | 4篇 |
1978年 | 10篇 |
1972年 | 3篇 |
1969年 | 5篇 |
1968年 | 4篇 |
1967年 | 2篇 |
1966年 | 6篇 |
1965年 | 2篇 |
1964年 | 2篇 |
1959年 | 2篇 |
1940年 | 2篇 |
1938年 | 2篇 |
排序方式: 共有1466条查询结果,搜索用时 15 毫秒
201.
The effect of increased tonicity on procaine-induced vacuolation in the H.Ep.2 cell has been investigated. An increase in tonicity equivalent to about 1·3% NaCl was found to reduce the formation of the drug-induced vacuoles and also to reduce established vacuolation. There appeared to be no difference in the effectiveness of the osmotic adjusting substances used (sodium chloride, sodium sulphate, glucose, fructose and sucrose) when employed in osmotically equivalent amounts. 相似文献
202.
203.
204.
Colorectal adenoma risk is modified by the interplay between polymorphisms in arachidonic acid pathway genes and fish consumption 总被引:4,自引:0,他引:4
Siezen CL van Leeuwen AI Kram NR Luken ME van Kranen HJ Kampman E 《Carcinogenesis》2005,26(2):449-457
Associations between polymorphisms in genes (SNPs) involved in the arachidonic acid (AA) pathway and colorectal adenomas have been investigated in a Dutch case control study including 384 cases and 403 polyp-free controls. Twenty-one polymorphisms in seven candidate genes were studied and a potential modifying effect of fish consumption was considered. A protective effect on colorectal adenomas was found for the CT genotype of SNP H477H in PPARgamma and the GC genotype of SNP V102V in COX-2 (OR 0.63, 95% CI 0.45-0.89 and OR 0.65, 95% CI 0.46-0.92, respectively) compared with the homozygous major genotypes. An increase in adenoma risk was observed for the TC genotype of SNP c.2242T-->C in COX-2 (OR 1.47, 95% CI 1.07-2.00) compared with the TT genotype. Analysis with estimated haplotypes confirmed these associations and revealed three additional associations with COX-2, sPLA(2) and 15LOX haplotypes. Fish consumption modified the associations with COX-2 and PPARdelta genotypes. For SNP c.-789C-->T in PPARdelta the major genotype showed a decrease in adenoma risk for those in the highest tertile of fish consumption (T3), as compared with the lowest tertile (T1) (OR 0.65, 95% CI 0.41-1.02). Protective effects were also observed for SNPs V102V and c.2242T-->C in COX-2 and high fish intake. The interaction between fish consumption and c.2242T-->C was statistically significant, with an OR for the TT genotype and high fish consumption of 0.52 (95% CI 0.27-1.01) as compared with low fish intake. These results indicate that SNPs in genes involved in the AA pathway are associated with colorectal adenoma risk. Some of these associations are modified by fish consumption. 相似文献
205.
OBJECTIVE: The socioeconomic variables of income, race and employment status have been shown to influence health-related quality of life (HRQL) scores in persons with asthma. However, little is known about the impact of other psychological factors or perceptions of economic hardship on HRQL in asthma, despite the known influence these have on general activity levels and emotional perceptions. The aim of the present study was to assess the relationships between psychological and socioeconomic factors and HRQL and on subsequent changes to HRQL over 12 months. METHODOLOGY: Consecutive adult patients with moderate or severe asthma attending outpatient clinics, emergency departments or who were inpatients at two teaching hospitals, completed surveys of clinical status, psychological and socioeconomic variables, and HRQL instruments (SF-36 and Modified Marks Asthma Quality of Life Questionnaire [MAQLQ-M]), at baseline and over 12-months follow-up. RESULTS: Of 343 eligible subjects, survey responses were received from 293 at baseline and 232 at 12-months. Mean age was 42 years (SD 18), 67% were female, 42% had moderate, and 58% severe current asthma clinical status according to the National Asthma Education and Prevention Program guidelines criteria. In random-effects multiple regression models, after adjusting for age, gender, education, income and hospital, significant independent variables associated with each of total MAQLQ-M, SF-36 Physical Component Summary (PCS) and SF-36 Mental Component Summary (MCS) scores were avoidance coping, perceived recent financial difficulties and clinical asthma status. Additional independent associations were, for total MAQLQ-M, patient concerns about costs delaying them from seeking care (overall model r(2) = 0.69); for PCS, active coping (r(2) = 0.69) and for MCS, positive evaluations/satisfaction with illness (r(2) = 0.54). CONCLUSION: Psychological factors, particularly coping styles, need to be taken into account when considering HRQL scores as outcome measures in asthma. Interventions to improve the coping capabilities of individuals with moderate-to-severe asthma may be potentially important areas for improvement of asthma-related HRQL. 相似文献
206.
207.
208.
Raimbault M Lavoué V Morcel K Hornung I Ninet I Mesbah H Porée P Descamps P Body G Levêque J 《Breast (Edinburgh, Scotland)》2011,20(4):380-384
Aims
The authors analyzed the outcome of patients with Isolated Skin Recurrence After Salvage Mastectomy (ISRASM) performed after conservative treatment for breast carcinoma, taking into account initial tumor characteristics, intramammary recurrence (first recurrence) characteristics, local skin recurrence (second recurrence) characteristics, and the type of treatment at each stage of the breast cancer continuum.Methods
Forty-two patients who had ISRASM between 1976 and 2007 were included in this retrospective study. Twenty-six factors were studied in univariate and multivariate analyses.Results
Mean Overall Survival (OS) was 70.3 (±4.1) months. The 5-year OS rate was 66.6%. 31% of patients did not present any recurrence, 52% had locoregional recurrence and 14% metastatic recurrence following ISRASM. Univariate analysis showed that 4 prognostic factors were significantly related to OS and/or Disease-Free Survival (DFS): (1) initial chemotherapy after primary breast cancer (P = 0.09 and 0.01 respectively), (2) presence of emboli at the site of intramammary recurrence (first recurrence) (P = 0.02 and 0.03), (3) interval between first and second surgery of less than 3 years (P = 0.09 and 0.0003), and (4) inflammatory skin involvement at ISRASM (P = 0.005 and 0.17). Multivariate analysis showed that presence of emboli at the site of intramammary recurrence was significantly related to OS and that an interval between first and second recurrence of less than 3 years was significantly related to DFS.Conclusion
Our results show that ISRASM affects a group of breast cancer patients with predominantly local rather than metastatic disease. Prognostic factors depend on characteristics at initial breast cancer, first recurrence and second recurrence. Evidence-based guidelines are still required for ISRASM management. 相似文献209.
Joepe J. Kaandorp Manon J.N.L. Benders Jan B. Derks Frank van Bel 《Paediatrics & Child Health》2010,20(8):356-361
Hypoxic-ischaemic encephalopathy is directly associated with the development of cerebral palsy and cognitive disabilities later in life, therefore remaining an important problem in perinatal medicine. Postnatal neuroprotective strategies have been investigated elaborately, but up to now, only moderate hypothermia proved to be beneficial in reducing post hypoxic-ischaemic encephalopathy in a selected group of asphyxiated neonates. Since the vast amount of toxic free radicals is produced in the reperfusion and reoxygenation period upon and immediately (30–60 min) after birth, we postulate that antenatal (i.e. maternal) pharmacologic neuroprotection of the foetus, combined with postnatal hypothermia, might be a more optimal approach to prevent this free radical induced brain damage. This review summarizes the molecular mechanisms underlying early reperfusion–reoxygenation damage and focuses on the most promising pharmacologic agents (phenobarbital, vitamin C and E, allopurinol, melatonin and xenon) to be given antenatally to the mother to neuroprotect the hypoxic foetus. 相似文献
210.
van Hensbergen Y Schipper LF Brand A Slot MC Welling M Nauta AJ Fibbe WE 《Experimental hematology》2006,34(7):943-950
OBJECTIVES: Hematopoietic recovery, in particular platelet reconstitution, can be severely delayed after transplantation with cord blood (CB) stem cells (SC). Expansion of CB SC may be one way to improve the recovery, but there is concern that ex vivo expansion compromises the repopulating ability of SC. METHODS: We used a short-term expansion protocol with TPO as single growth factor. The expanded cells were tested in the NOD/SCID mouse model and both platelet recovery and repopulation capacity were examined and compared with unexpanded CD34+ CB cells of the same CB donor. RESULTS: Platelet recovery started 1 week earlier in mice transplanted with TPO-expanded CD34+ cells and at days 5 and 8 after transplantation, 6.2 +/- 2.6 and 13.9 +/- 6.7 plt/microL were observed, respectively. At similar time intervals 0.0 and 1.5 +/- 0.2 plt/microL respectively were detected in mice receiving the unmanipulated CD34+ grafts. This was accompanied by a higher number of CFU-Mk in the bone marrow (BM) 7 days after transplantation. Moreover, the BM engraftment and the lineage differentiation of human cells at 6 weeks after transplantation was similar, suggesting that long-term engraftment was not compromised by the expansion procedure. CONCLUSION: Ex vivo expansion with TPO as single growth factor results in an accelerated platelet recovery in NOD/SCID mice and appears not to affect the long-term repopulation capacity. 相似文献