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   10223篇
  免费   652篇
  国内免费   141篇
  11016篇
  2023年   64篇
  2022年   167篇
  2021年   242篇
  2020年   175篇
  2019年   185篇
  2018年   255篇
  2017年   209篇
  2016年   305篇
  2015年   376篇
  2014年   428篇
  2013年   588篇
  2012年   663篇
  2011年   616篇
  2010年   417篇
  2009年   319篇
  2008年   447篇
  2007年   429篇
  2006年   353篇
  2005年   356篇
  2004年   294篇
  2003年   303篇
  2002年   285篇
  2001年   250篇
  2000年   216篇
  1999年   195篇
  1998年   101篇
  1997年   74篇
  1996年   61篇
  1994年   61篇
  1992年   164篇
  1991年   131篇
  1990年   168篇
  1989年   130篇
  1988年   133篇
  1987年   127篇
  1986年   109篇
  1985年   117篇
  1984年   104篇
  1983年   84篇
  1982年   82篇
  1981年   115篇
  1980年   87篇
  1979年   110篇
  1978年   94篇
  1977年   87篇
  1976年   64篇
  1975年   73篇
  1974年   68篇
  1973年   64篇
  1972年   58篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
111.
112.

Background

Studies from high-income countries have shown that women receive less aggressive diagnostics and treatment than men in acute coronary syndromes (ACS), though their short-term mortality does not appear to differ from men. Data on gender differences in ACS presentation, management, and outcomes are sparse in India.

Methods and Results

The Detection and Management of Coronary Heart Disease (DEMAT) Registry collected data from 1,565 suspected ACS patients (334 women; 1,231 men) from ten tertiary care centers throughout India between 2007–2008. We evaluated gender differences in presentation, in-hospital and discharge management, and 30-day death and major adverse cardiovascular event (MACE; death, re-hospitalization, and cardiac arrest) rates. Women were less likely to present with STEMI than men (38% vs. 55%, p<0.001). Overall inpatient diagnostics and treatment patterns were similar between men and women after adjustment for potential confounders. Optimal discharge management with aspirin, clopidogrel, beta-blockers, and statin therapy was lower for women than men, (58% vs. 65%, p = 0.03), but these differences were attenuated after adjustment (OR = 0.86 (0.62, 1.19)). Neither the outcome of 30-day mortality (OR = 1.40 (0.62, 3.16)) nor MACE (OR = 1.00 (0.67, 1.48)) differed significantly between men and women after adjustment.

Conclusions

ACS in-hospital management, discharge management, and 30-day outcomes did not significantly differ between genders in the DEMAT registry, though consistently higher treatment rates and lower event rates in men compared to women were seen. These findings underscore the importance of further investigation of gender differences in cardiovascular care in India.  相似文献   
113.
114.
115.
116.
The aim of this work was to study the effect of a high voltage pulsed electric field (PEF) on the inactivation of E. coli in cranberry juice to achieve the regulatory requirement of a 5‐log reduction in the microbial count. PEF processing involved the application of high voltage pulses to liquid or semi‐solid materials, placed between two electrodes at ambient, sub‐ambient, or supra‐ambient temperature. In this work, cranberry juice, inoculated with E. coli was subjected to 60 pulses in the voltage range of 5 to 40 kV/cm. The experiments were carried out at 20 °C. The temperature rise was less than 2 °C at the average treatment time of 80 s. PEF is an emerging non‐thermal technology for food preservation that retains the natural taste of food. It has mainly been applied to improve the shelf life of such foods as milk, liquid eggs and fruit juices.  相似文献   
117.
118.
The skin cells chiefly depend on carbohydrate metabolism for their energy requirement during cutaneous wound healing. Since the glucose metabolism is greatly hampered in diabetes and this might affect wound repair process. This prompted us to investigate the intermediate steps of energy metabolism by measuring enzyme activities in the wound tissues of normal and streptozotocin-induced diabetic rats following excision-type of cutaneous injury. The activities of key regulatory enzymes namely hexokinase (HK), phosphofructokinase (PFK), lactate dehydrogenase (LDH), citrate synthase (CS) and glucose-6 phosphate dehydrogenase (G6PD) have been monitored in the granulation tissues of normal and diabetic rats at different time points (2, 7, 14 and 21 days) of postwounding. Interestingly, a significant alteration in all these enzyme activities was observed in diabetic rats. The activity of PFK was increased but HK, LDH and CS showed a decreased activity in the wound tissue of diabetics as compared to normal rats. However G6PD exhibited an elevated activity only at early stage of healing in diabetic rats. Thus, the results suggest that significant alterations in the activities of energy metabolizing enzymes in the wound tissue of diabetic rats may affect the energy availability for cellular activity needed for repair process and this may perhaps be one of the factor responsible for impaired healing in these subjects. (Mol Cell Biochem 270: 71–77, 2005)  相似文献   
119.
 The potential of DNA markers such as microsatellites, minisatellites and RAPDs was investigated in pearl millet [Pennisetum glaucum (L.) R. Br] with respect to their abundance and variability. Southern analysis, using 22 different di-, tri-, tetra- and penta-oligonucleotide probes and five minisatellite probes, identified (GATA)4 as the most useful probe for the detection of multiple polymorphic fragments among pearl millet cultivars and landraces from India. The clustering patterns of pearl millet cultivars and landraces based on (GATA)4 and RAPD (randomly amplified polymorphic DNA) markers differed. The landraces, representing eight states in India, could not be grouped based on their geographical distribution with the DNA markers. RAPD analysis revealed a high degree of genetic diversity among the cultivars and landraces employed in this study. The probability of an identical match by chance for any two genotypes using (GATA)4 and RAPDs was 3.02×10-20 for cultivars and 5.2×10-9 for landraces. The microsatellite (GATA)4 and RAPDs provide useful tools for genotype identification and for the assessment of genetic relationships in pearl millet. Received: 19 October 1997 / Accepted: 9 December 1997  相似文献   
120.
We have studied the effect of 2,2,2-trifluoroethanol (TFE), an α-helix inducer, versus methyl cyanide (MeCN), a β-sheet inducer, on acid-denatured human serum albumin (HSA) using far-UV circular dichroism, intrinsic fluorescence, 1-anilino-8-naphthalene sulfonate binding, and acrylamide quenching studies. Interestingly, at pH 2.0, where the recovery and resolution of the protein in reverse phase chromatography is high, its secondary structure remains unchanged even in the presence of very high concentration (76% v/v) of MeCN. Gain of 23 and 34% α-helicity was observed in the presence of 20 and 50% TFE, respectively. At pH 7.3, HSA aggregates in the presence of 40% MeCN, but it remains soluble up to 75% MeCN at pH 2.0. The results seem to be important for HSA isolation and purification.  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