首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   459篇
  免费   31篇
  490篇
  2024年   1篇
  2023年   1篇
  2022年   2篇
  2021年   4篇
  2020年   1篇
  2019年   3篇
  2018年   12篇
  2017年   6篇
  2016年   13篇
  2015年   14篇
  2014年   14篇
  2013年   30篇
  2012年   35篇
  2011年   33篇
  2010年   15篇
  2009年   18篇
  2008年   27篇
  2007年   32篇
  2006年   34篇
  2005年   32篇
  2004年   35篇
  2003年   25篇
  2002年   30篇
  2001年   4篇
  2000年   2篇
  1999年   3篇
  1998年   8篇
  1996年   3篇
  1995年   1篇
  1994年   2篇
  1993年   4篇
  1992年   4篇
  1991年   5篇
  1990年   5篇
  1989年   11篇
  1988年   3篇
  1987年   1篇
  1986年   5篇
  1985年   1篇
  1984年   1篇
  1983年   2篇
  1982年   1篇
  1979年   1篇
  1978年   1篇
  1977年   1篇
  1976年   1篇
  1975年   2篇
  1974年   1篇
排序方式: 共有490条查询结果,搜索用时 0 毫秒
101.
102.
103.
104.

Introduction

The objective of this study was to evaluate the long-term safety and efficacy of tabalumab, a monoclonal antibody that neutralizes membrane-bound and soluble B-cell-activating factor, in rheumatoid arthritis (RA) patients.

Methods

Patients with RA who completed one of two 24-week randomized controlled trials (RCTs) participated in this 52-week, flexible-dose, open-label extension study. Patients in RCT1 received intravenous placebo, 30-mg tabalumab or 80-mg tabalumab every 3 weeks, and patients in RCT2 received subcutaneous placebo or 1-, 3-, 10-, 30-, 60- or 120-mg tabalumab every 4 weeks (Q4W). Regardless of prior treatment, all patients in this study received subcutaneous 60-mg tabalumab Q4W for the first 3 months, then a one-time increase to 120-mg tabalumab Q4W (60-mg/120-mg group) and a one-time decrease to 60-mg tabalumab Q4W per patient was allowed (60-mg/120-mg/60-mg group).

Results

There were 182 patients enrolled: 60 mg (n = 60), 60/120 mg (n = 121) and 60/120/60 mg (n = 1). Pretabalumab baseline disease activity was generally higher in the 60-mg/120-mg group. There was a higher frequency of serious adverse events and treatment-emergent adverse events, as well as infections and injection-site reactions, in the 60-mg/120-mg group. One death unrelated to the study drug occurred (60-mg/120-mg group). In both groups, total B-cell counts decreased by approximately 40% from the baseline level in the RCT originating study. Both groups demonstrated efficacy through 52 weeks of treatment relative to baseline pretabalumab disease activity based on American College of Rheumatology criteria improvement ≥20%, ≥50% and ≥70%; European League against Rheumatism Responder Index in 28 joints; Disease Activity Score in 28 joints–C-reactive protein; and Health Assessment Questionnaire–Disability Index.

Conclusions

With long-term, open-label tabalumab treatment, no unexpected safety signals were observed, and B-cell reductions were consistent with previous findings. Despite differences in RCT originating studies, both groups demonstrated an efficacy response through the 52-week extension.

Trial registration

ClinicalTrials.gov Identifier: NCT00837811 (registered 3 February 2009).

Electronic supplementary material

The online version of this article (doi:10.1186/s13075-014-0415-2) contains supplementary material, which is available to authorized users.  相似文献   
105.
This paper examines environmental and behavioral determinants of the habitat use and preferences of Indo-Pacific humpback dolphins inhabiting the Algoa Bay region on the south Eastern Cape coast of South Africa. In order to quantify the habitat use and preference, two indices were used, the Coefficient of Area Use (AU) and the Activity Index (AI). The dolphins inhabit a narrow strip of shallow, inshore waters of Algoa Bay and remain mostly within 400 m of the shore, in water less than 15 m deep, with no apparent preference for clear or turbid water. Water depth is probably the main factor limiting their inshore distribution, and the 25-m isobath seems to represent the critical depth. Within this confined, inshore distribution, dolphin activities concentrate in the vicinity of rocky reefs-their primary feeding grounds. Dolphin dependence on these shallow-water habitats is evident throughout the year and, consequently, the inshore shallow reefs are identified as the "key habitat" which is of primary importance for humpback dolphins in Eastern Cape waters. The dolphins' dependence on this restricted type of habitat within an already restricted inshore distribution makes them particularly vulnerable to alteration or loss of this habitat.  相似文献   
106.
Differential thermal analysis indicated that the frost resistance of winter rape leaves ( Brassica napus L. var. oleifera L. cv. Gòrczanski), collected from plants grown in the cold (5/2°C), relies mainly on their ability to supercool to −9 to −11°C, i.e. consists in freezing avoidance. Initiation of ice formation in the cold-acclimated leaves resulted in the death of more than 50% of the cells as determined with a conductivity method. The development of freezing tolerance appeared to be an attribute of the second stage of plant hardening and was induced by the exposure of plants to a slightly subzero temperature (−5°C) for 18 h. Such a treatment brought about a sudden and persistent water potential decrease in the leaves, despite the fact that they had reabsorbed water from the medium prior to water potential measurements. Water potential changes were associated with a higher growth capability of the leaves as checked by determinations of disk area increments. It is suggested that the increased frost tolerance of the cold-grown winter rape leaves, subjected to subfreezing temperature, is related to the decreased water potential of the tissue caused by changes in turgor and/or in osmotic pressures of the cells.  相似文献   
107.
Klinefelter's syndrome (47, XXY) is the most common chromosome aneuploidy in men and is usually characterized by underdeveloped testes and sterility. The aim of the present study was to detect cellular distribution of androgen receptors (AR) and aromatase in testes of patient with KS. The tissue sections were processed for morphological and immunohistochemical staining. Additionally, levels of FSH, LH, PRL, estradiol, and testosterone were measured in the plasma. Morphological analysis revealed a complete absence of spermatogenesis. No germ cells were present in seminiferous tubules. In some tubules, nests of apparently degenerating Sertoli cells were found. In the interstitium, Leydig cell hyperplasia was observed. Using immunohistochemistry, nuclear AR staining was detected in Sertoli cells and peritubular cells, whereas in Leydig cells the staining was exclusively cytoplasmic. The immunostaining of aromatase was detected in the cytoplasm of Sertoli cells and Leydig cells. Increased levels of gonadotropins and decreased level of testosterone concomitantly with the cytoplasmic localization of AR in Leydig cells might contribute to the impaired testicular function in patient with KS.  相似文献   
108.
The growth of fish is directly dependent on feed composition and quality. Medicinal plants can be added to fish feed as adjuvant therapy for the prevention of fish diseases. The purple coneflower (Echinacea purpurea (L.) Moench.) has been reported to have multiple biological effects, including immunomodulatory and antioxidant activity. The most active compounds of E. purpurea are polyphenols - caffeic acid derivatives: caftaric acid, chlorogenic acid, cynarin, echinacoside and cichoric acid.Due to a relatively limited number of studies on the use of the purple coneflower as a nutritional supplement for fish feeding, extruded fish feed with addition of Echinacea roots was produced. In the feed total phenolic content, selected polyphenol contents, the energetic value, nutrient contents and antioxidant capacity were examined.The results indicate that fish feed with addition of the Echinacea has a great potential to be a good source of natural radical scavengers, for example polyphenols, and nutritive ingredients. Antioxidant properties of feed were well correlated with the coneflower content. The study findings confirmed that high-temperature extrusion-cooking process does not deactivate phenolic antioxidant compounds, which are present both in the Echinacea roots and in the final product. Fish feed with addition of E. purpurea can be used as a nutritional supplement in the prevention of fish diseases caused by oxidative stress.  相似文献   
109.
110.
The study aimed at optimization of DNA isolation from blood of representatives of four microbial groups causing sepsis, i.e., Gram negative: Escherichia coli, Gram positive: Staphylococcus aureus, yeast: Candida albicans, and filamentous fungus: Aspergillus fumigatus. Additionally, the five commercial kits for microbial DNA isolation from the blood were tested. The developed procedure of DNA isolation consisted of three consecutive steps, i.e., mechanical disruption, chemical lysis, and thermal lysis. Afterward, DNA was isolated from the previously prepared samples (erythrocyte lysis) with the use of five commercial kits for DNA isolation. They were compared paying heed to detection limit, concentration, DNA purity, and heme concentration in samples. The isolation of DNA without preliminary erythrocyte lysis resulted in far higher heme concentration than when lysis was applied. In the variant with erythrocyte lysis, two of the commercial kits were most effective in purifying the DNA extract from heme. Designed procedure allowed obtaining microbial DNA from all four groups of pathogens under study in the amount sufficient to conduct the rtPCR reaction, which aimed at detecting them in the blood.  相似文献   
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号