全文获取类型
收费全文 | 1830篇 |
免费 | 126篇 |
国内免费 | 13篇 |
专业分类
耳鼻咽喉 | 3篇 |
儿科学 | 39篇 |
妇产科学 | 7篇 |
基础医学 | 204篇 |
口腔科学 | 38篇 |
临床医学 | 200篇 |
内科学 | 830篇 |
皮肤病学 | 33篇 |
神经病学 | 49篇 |
特种医学 | 140篇 |
外科学 | 158篇 |
综合类 | 44篇 |
预防医学 | 60篇 |
眼科学 | 35篇 |
药学 | 66篇 |
1篇 | |
中国医学 | 1篇 |
肿瘤学 | 61篇 |
出版年
2023年 | 4篇 |
2022年 | 5篇 |
2021年 | 15篇 |
2020年 | 14篇 |
2019年 | 27篇 |
2018年 | 38篇 |
2017年 | 15篇 |
2016年 | 22篇 |
2015年 | 30篇 |
2014年 | 53篇 |
2013年 | 73篇 |
2012年 | 73篇 |
2011年 | 93篇 |
2010年 | 72篇 |
2009年 | 61篇 |
2008年 | 82篇 |
2007年 | 92篇 |
2006年 | 95篇 |
2005年 | 93篇 |
2004年 | 83篇 |
2003年 | 83篇 |
2002年 | 75篇 |
2001年 | 71篇 |
2000年 | 61篇 |
1999年 | 69篇 |
1998年 | 54篇 |
1997年 | 62篇 |
1996年 | 52篇 |
1995年 | 28篇 |
1994年 | 39篇 |
1993年 | 30篇 |
1992年 | 22篇 |
1991年 | 23篇 |
1990年 | 31篇 |
1989年 | 31篇 |
1988年 | 37篇 |
1987年 | 27篇 |
1986年 | 17篇 |
1985年 | 12篇 |
1984年 | 16篇 |
1983年 | 17篇 |
1982年 | 13篇 |
1981年 | 13篇 |
1980年 | 12篇 |
1979年 | 4篇 |
1978年 | 4篇 |
1976年 | 7篇 |
1975年 | 3篇 |
1969年 | 4篇 |
1967年 | 3篇 |
排序方式: 共有1969条查询结果,搜索用时 15 毫秒
91.
Karsten Wursthorn Jerzy Jaroszewicz Behrend J. Zacher Martina Darnedde Regina Raupach Ingmar Mederacke Markus Cornberg Michael P. Manns Heiner Wedemeyer 《Journal of clinical virology》2011,50(4):292-296
BackgroundHepatitis B surface antigen (HBsAg) clearance during chronic hepatitis B (CHB) infection is associated with improved long-term clinical outcome, so is considered an important therapeutic goal in CHB. Studies have shown that serum HBsAg quantification during, and at end of, treatment may predict long-term HBsAg loss.ObjectivesPerformance comparison of the qualitative Elecsys HBsAg II assay using a quantitative research protocol and an established quantitative HBsAg assay.Study designA dilution algorithm was developed for the Elecsys HBsAg II assay to allow quantification of HBsAg levels; this was used to measure HBsAg levels in a range of samples including sera from patients infected with different HBV genotypes, HBV mutants, and longitudinal samples from patients undergoing antiviral treatment. Results were compared with those from the quantitative Architect HBsAg assay.ResultsThere was significant overall correlation between Elecsys and Architect assays (correlation coefficient [r] = 0.97; p < 0.001). HBsAg levels measured with both assays correlated well in all phases of infection (r = 0.80–0.96), across all genotypes tested (HBV genotype A, r = 0.89; HBV genotype D, r = 0.97), and in samples with lamivudine-resistant mutations (r = 0.94). Bland–Altman analysis showed only minor discordance between assays in different phases of chronic HBV-infection (3.8–5.1%). This strong correlation was also present for sera with lower HBsAg concentrations. On-treatment HBsAg levels were similar when measured with either assay.ConclusionsUsing a simple dilution algorithm, the quantitative Elecsys HBsAg II assay reliably determined serum HBsAg levels in a wide range of samples, and showed very high correlation with the Architect HBsAg assay. 相似文献
92.
93.
94.
Ingmar Mederacke Heiner Wedemeyer Sandra Ciesek Eike Steinmann Regina Raupach Karsten Wursthorn Michael P. Manns Hans Ludger Tillmann 《Journal of clinical virology》2009,46(3):210-215
BackgroundRecently, a novel quantitative HCVcoreAg immunoassay developed for commercialisation by Abbott has become available in Europe and Asia.ObjectivesWe evaluated the correlation of HCV-RNA and HCVcoreAg and investigated the stability of HCVcoreAg and HCV-RNA.Study designHCVcoreAg was quantified by a novel fully automated immunoassay (Architect HCVAg, Abbott, Germany). HCV-RNA quantification was performed either using the Cobas-TaqMan assay or Amplicor-HCV-Monitor (Roche-Diagnostics, Germany). Correlation of HCVcoreAg with HCV-RNA was studied cross-sectionally and longitudinally in untreated patients followed for up to 8 years. Stability of HCVcoreAg and HCV-RNA was evaluated in plasma and whole blood stored for up to 96 h at different conditions.ResultsHCVcoreAg showed good correlation with HCV-RNA in all 118 cross-sectional tested samples irrespective of the HCV genotype (r = 0.75). In the majority but not all of the 10 longitudinally studied patients HCVcoreAg also demonstrated a good correlation with HCV-RNA. HCVcoreAg was stable in plasma at 4, 20, and 37 °C for up to 96 h, whereas HCV-RNA significantly declined at 37 °C. In whole blood, HCVcoreAg and HCV-RNA levels declined at all conditions with exception of HCVcoreAg at 37 °C. HCVcoreAg was stable after 1–5 freezing/thawing cycles and not light-sensitive.ConclusionsHCVcoreAg represents a stable and reliable marker of viral replication showing a good correlation with HCV-RNA irrespective of the HCV genotype. HCVcoreAg determination can be used to confirm viral replication and monitor viral load or acquisition of HCV over time. 相似文献
95.
Bhattacharya S; MacLennan F; Hamilton MP; Templeton A 《Human reproduction (Oxford, England)》1997,12(7):1440-1442
Although the conventional method of pain relief during outpatient oocyte
recovery involves physician-administered drugs, patient- controlled
analgesia (PCA) offers an alternative technique with the potential to give
women more control over peroperative analgesia. We conducted a prospective
randomized study to compare the effect of fentanyl administered either
through a PCA delivery system or by a physician. Thirty-nine women were
randomized to PCA during egg collection while 42 were allocated to receive
intermittent doses administered by a physician. Pain was evaluated by means
of a 100 mm linear analogue scale. The mean (SD) pain score in the PCA
group was 38.5 (19.8) while in the other group it was 46.1 (21.3) (P =
0.1). In the PCA group, 64% of women felt very satisfied with their
analgesia as compared with 57% in the non-PCA group (P = 0.6). Among the
PCA users, 39% of demands were successful. Significantly more fentanyl
(97.5 microg) was used in the PCA group than in the other group (84.6
microg) (P = 0.03). Though intraoperative PCA with fentanyl is an effective
alternative to physician-administered techniques, many women still feel the
need for more analgesia during the procedure.
相似文献
96.
97.
Novero V; Camus M; Tournaye H; Smitz J; Verheyen G; Joris H; Derde MP; Van Steirteghem AC; Devroey P 《Human reproduction (Oxford, England)》1997,12(1):59-63
Serum follicle stimulating hormone (FSH) is routinely measured when
evaluating the infertile male for intracytoplasmic sperm injection (ICSI).
However, among the sperm parameters, only its relationship with sperm
concentration is well documented. Few investigations concern the
relationship between FSH and sperm motility and morphology, and the results
of ICSI. A retrospective study of 316 couples who underwent ICSI was
carried out to determine the relationships between serum FSH concentrations
in the male and (i) standard sperm parameters_(concentration, motility and
morphology) and (ii) fertilization, cleavage, pregnancy and implantation
rates after ICSI. There was an inverse correlation with sperm concentration
and total motility but no relationship was found with progressive motility
and sperm morphology. Neither was any relationship found between serum FSH
and fertilization, cleavage, pregnancy and implantation rates, and the
results of ICSI. These findings suggest the need to review the routine
measurement of serum FSH in the infertile male when ICSI is the planned
treatment procedure.
相似文献
98.
Over the past decade, the unfortunate reality is that the income gap has widened between Canadian families. Educational outcomes are one of the key areas influenced by family incomes. Children from low-income families often start school already behind their peers who come from more affluent families, as shown in measures of school readiness. The incidence, depth, duration and timing of poverty all influence a child’s educational attainment, along with community characteristics and social networks. However, both Canadian and international interventions have shown that the effects of poverty can be reduced using sustainable interventions. Paediatricians and family doctors have many opportunities to influence readiness for school and educational success in primary care settings. 相似文献
99.
The objectives of the present review is to update readers with the rapidly changing concepts in liver stem cell biology and related clinical applications. The liver has adapted to the inflow of ingested toxins by the evolutionary development of unique regenerative properties and responds to injury or tissue loss by rapid division of the mature cells, hepatocytes, and bile duct epithelial cells. Proliferation of the parenchymal cells is regulated by numerous cytokine/growth factor-mediated pathways and is timely synchronized with extracellular matrix degradation and the restoration of the vasculature. The putative role of stem cells in physiology, pathophysiology, and therapy is not yet precisely known but currently is under intensive investigation. Resident hepatic stem/ progenitor cells have been identified in small numbers and implicated in liver tissue repair, when hepatocyte and bile duct replication capacity is exhausted or experimentally inhibited. Several independent reports have suggested that bone marrow cells can give rise to different hepatic epithelial cells types, including hepatic stem cells, hepatocytes, and bile duct epithelium. These observations have resulted in the hypothesis that extrahepatic stem cells, specifically bone marrow-derived stem cells, are an important source for liver epithelial cell replacement, particularly during chronic injury. Most of published data, however, now suggest that they do not play a relevant role in replacement of epithelial cells in any known form of hepatic injury. In vitro differentiation protocols for various adult extrahepatic stem cells might eventually provide valuable sources of cells for transplantation and therapy. Amniotic epithelial stem cells, fetal liver progenitor cells as well as embryonic stem cells currently emerge as alternative stem cell sources and open new possibilities for cellular therapies of liver disease. 相似文献
100.
Quantitative gene expression analysis reveals transition of fetal liver progenitor cells to mature hepatocytes after transplantation in uPA/RAG-2 mice 总被引:14,自引:0,他引:14 下载免费PDF全文