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151.
152.
Along Zhao Leilei Yang Kui Ma Mengli Sun Lei Li Jin Huang 《Cell cycle (Georgetown, Tex.)》2016,15(5):644-653
It has been reported that Wnt/β-catenin is critical for dedifferentiation of differentiated epidermal cells. Cyclin D1 (CCND1) is a β-catenin target gene. In this study, we provide evidence that overexpression of CCND1 induces reprogramming of epidermal cells into stem cell-like cells. After introducing CCND1 gene into differentiated epidermal cells, we found that the large flat-shaped cells with a small nuclear-cytoplasmic ratio changed into small round-shaped cells with a large nuclear-cytoplasmic ratio. The expressions of CK10, β1-integrin, Oct4 and Nanog in CCND1 induced cells were remarkably higher than those in the control group (P < 0.01). In addition, the induced cells exhibited a high colony-forming ability and a long-term proliferative potential. When the induced cells were implanted into a wound of laboratory animal model, the wound healing was accelerated. These results suggested that overexpression of CCND1 induced the reprogramming of differentiated epidermal cells into stem cell-like cells. This study may also offer a new approach to yield epidermal stem cells for wound repair and regeneration. 相似文献
153.
The use of transgenic livestock is providing new methods for obtaining pharmaceutically useful proteins. However, the protein expression profiles of the transgenic animals, including expression of milk fat globule membrane (MFGM) proteins, have not been well characterized. In this study, we compared the MFGM protein expression profile of the colostrum and mature milk from three lines of transgenic cloned (TC) cattle, i.e., expressing recombinant human α-lactalbumin (TC-LA), lactoferrin (TC-LF) or lysozyme (TC-LZ) in the mammary gland, with those from cloned non-transgenic (C) and conventionally bred normal animals (N). We identified 1, 225 proteins in milk MFGM, 166 of which were specifically expressed only in the TC-LA group, 265 only in the TC-LF group, and 184 only in the TC-LZ group. There were 43 proteins expressed only in the transgenic cloned animals, but the concentrations of these proteins were below the detection limit of silver staining. Functional analysis also showed that the 43 proteins had no obvious influence on the bovine mammary gland. Quantitative comparison revealed that MFGM proteins were up- or down-regulated more than twofold in the TC and C groups compared to N group: 126 in colostrum and 77 in mature milk of the TC-LA group; 157 in colostrum and 222 in mature milk of the TC-LF group; 49 in colostrum and 98 in mature milk of the TC-LZ group; 98 in colostrum and 132 in mature milk in the C group. These up- and down-regulated proteins in the transgenic animals were not associated with a particular biological function or pathway, which appears that expression of certain exogenous proteins has no general deleterious effects on the cattle mammary gland. 相似文献
154.
Zhang Hao Qing Zhao Xue Qiang Chen Yi Ling Zhang Ling Yu Shen Ren Fang 《Plant and Soil》2019,439(1-2):293-308
Plant and Soil - Biocrusts are important functional units in dryland ecosystems. Regarded as ecosystem engineers, cyanobacteria in biocrusts contribute several major physico-chemical and biological... 相似文献
155.
Zhao P 《The Yale journal of biology and medicine》2011,84(2):125-129
Over the past 200 years, there have been countless groundbreaking discoveries in biology and medicine at Yale University. However, one particularly noteworthy discovery with profoundly important and broad consequences happened here in just the past two decades. In 2009, Thomas Steitz, the Sterling Professor of Molecular Biophysics & Biochemistry, was awarded the Nobel Prize in Chemistry for "studies of the structure and function of the ribosome," along with Venkatraman Ramakrishnan of the MRC Laboratory of Molecular Biology and Ada E. Yonath of the Weizmann Institute of Science. This article covers the historical context of Steitz's important discovery, the techniques his laboratory used to study the ribosome, and the impact that this research has had, and will have, on the future of biological and medical research. 相似文献
156.
Hong-Jin Zhao Yan Li De-Yu Wang Hai-Tao Yuan 《Journal of cellular and molecular medicine》2021,25(23):11031-11034
The administration of ACEI/ARB (angiotensin-converting enzyme inhibitors/Angiotension II receptor blockers) in COVID-19 (coronavirus disease 2019) patients with hypertension exhibits a lower risk of mortality compared with ACEI/ARB non-users. In this context, an important question arises: is ACEI or ARB more suitable for the treatment of hypertensive COVID-19 patients? Taken into consideration the following four rationales, ARB may offer a more significant benefit than ACEI for the short-term treatment of hypertensive COVID-19 patients: 1. ACEI has no inhibition on non-ACE-mediated Ang II production under infection conditions, whereas ARB can function properly regardless of how Ang II is produced; 2. ACEI-induced bradykinin accumulation may instigate severe ARDS while ARB has no effects on kinin metabolism; 3. ARB alleviates viscous sputa production and inflammatory reaction significantly in contrast to ACEI; 4. ARB may attenuate the lung fibrosis induced by mechanical ventilation in severe patients and improve their prognosis significantly compared with ACEI. To examine the advantages of ARB over ACEI on hypertensive COVID-19 patients, retrospective case-control studies comparing the clinical outcomes for COVID-19 patients receiving ARB or ACEI treatment is strikingly needed in order to provide guidance for the clinical application. 相似文献
157.
With medical costs escalating over recent years, cost analysis is being conducted more and more to assess economic impact of new treatment options. An incremental cost-effectiveness ratio (ICER) is a measure that assesses the additional cost for a new treatment for each additional unit of effectiveness, such as saving 1 year of life. In this article, we consider cost-effectiveness analysis for new treatments evaluated in a randomized clinical trial setting with staggered entries. In particular, the censoring times are different for cost and survival data. We propose a method for estimating the ICER and obtaining its confidence interval when differential censoring exists. Simulation experiments are conducted to evaluate our proposed method. We also apply our methods to a clinical trial example comparing the cost-effectiveness of implanted defibrillators with conventional therapy for individuals with reduced left ventricular function after myocardial infarction. 相似文献
158.
Promoter optimisation of lentiviral vectors for efficient insulin gene expression in canine mesenchymal stromal cells: potential surrogate beta cells 下载免费PDF全文
159.
Wen X Wang T Wang Z Li L Zhao C 《International journal of biological macromolecules》2008,42(3):256-263
In this study, hydrogels for DNA-controlled release was prepared with konjac glucomannan (KGM), a water-soluble non-ionic polysaccharide, by means of deacetylated reaction and physically cross-linking method under mild conditions. The properties of the KGM hydrogels were analyzed by FTIR spectra and scanning electron microscopy (SEM). The integrality of the released DNA was investigated by circular dichroism (CD). The DNA release kinetics was performed using the DNA-loaded KGM gels in buffer solutions of pH 7.4 at 37+/-0.5 degrees C. Peppas model and Higuchi model were used to analysis the DNA release mechanism; the data indicated that the DNA release can be controlled by changing the preparation conditions and the structure parameters of the gels. This study suggested that the KGM hydrogels have a potential use for advanced controlled release. 相似文献
160.
Functional Characterization of 14 Pht1 Family Genes in Yeast and Their Expressions in Response to Nutrient Starvation in Soybean 总被引:1,自引:0,他引:1
Lu Qin Yongxiang Guo Liyu Chen Ruikang Liang Mian Gu Guohua Xu Jing Zhao Thomas Walk Hong Liao 《PloS one》2012,7(10)