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991.
Marcelo H Ratto Louis TJ Delbaere Yvonne A Leduc Roger A Pierson Gregg P Adams 《Reproductive biology and endocrinology : RB&E》2011,9(1):24
Background
The objective of the present study was to isolate and purify the protein fraction(s) of llama seminal plasma responsible for the ovulation-inducing effect of the ejaculate. 相似文献992.
993.
Severe acute pancreatitis (SAP) is a common disease with a poor prognosis. Heart failure is one cause of SAP patient death.
Intermedin (IMD) is a potent endogenous cardio-protective substance. Administration of exogenous IMD showed beneficial effects
in cardiovascular diseases. The aim of this study was to investigate the myocardial damage in SAP and to determine the therapeutic
potential of IMD for SAP. Using an SAP rat model, we examined endogenous IMD expression following SAP induction, and determined
the effect of IMD on myocardial function, histological morphology, apoptosis-related gene expression, and prognosis. Our results
indicated that the cardiac function and histological structure were significantly disrupted in SAP rats. Infusion of exogenous
IMD significantly preserved cardiac function and ameliorated myocardial damage. Terminal deoxynucleotidyl transferase-mediated
dUTP nick end labeling (TUNEL) revealed that myocardial apoptosis was extensively present in SAP rats, and IMD infusion led
to increased expression of the prosurvival factor Bcl-2, but decreased pro-apoptotic factors Bax and caspase-3. In addition,
IMD infusion also reversed the change of IMD receptor systems in SAP rat heart tissue. Furthermore, we found that IMD infusion
greatly decreased mortality of SAP rats. In conclusion, administration of SAP produced therapeutic effects in SAP through
modulating apoptotic and pro-survival gene expression, inhibiting myocardial apoptosis, preserving cardiac function, and a
useful therapeutic agent for SAP, and provides us an insight for a clinical trial of IMD for treating human severe acute pancreatitis. 相似文献
994.
The ethical issues and public concerns regarding the use of embryonic stem (ES) cells in human therapy have motivated considerable
research into the generation of pluripotent stem cell lines from non-embryonic sources. Numerous reports have shown that pluripotent
cells can be generated and derived from germline stem cells (GSCs) in mouse and human testes during in vitro cultivation. The gene expression patterns of these cells are similar to those of ES cells and show the typical self-renewal
and differentiation patterns of pluripotent cells in vivo and in vitro. However, the mechanisms underlying the spontaneous dedifferentiation of GSCs remain to be elucidated. Studies to identify
master regulators in this reprogramming process are of critical importance for understanding the gene regulatory networks
that sustain the cellular status of these cells. The results of such studies would provide a theoretical background for the
practical use of these cells in regenerative medicine. Such studies would also help elucidate the molecular mechanisms underlying
certain diseases, such as testicular germ cell tumors. 相似文献
995.
996.
分子标记技术的发展及应用 总被引:13,自引:0,他引:13
介绍了几种应用前景较广的分子标记,如基于DNA杂交技术的分子标记:限制性片段长度多态性(RFLP)和DNA可变串联重复数标记(VNRT);基于PCR技术的分子标记:随机扩增多态性 DNA(RAPD)、酶切扩增多态性(CAPS)、扩增片段长度多态性(AFLP)、微卫星DNA(SSR)和DNA单链构象多态性(SSCP);以及新兴的第3代分子标记,即基于DNA芯片技术的分子标记:单核苷酸多态性(SNP)等。分别阐述了它们的原理、方法步骤与优缺点、应用注意事项和适用范围,同时概述了它们在生物学研究中的应用和进展。 相似文献
997.
Natalia A. Kolganova Vadim A. Vasiliskov Viktoriya E. Kuznetsova Valeriy E. Shershov Sergey A. Lapa Timur O. Guseinov Maksim A. Spitsyn Edward N. Timofeev Alexander V. Chudinov 《Molecular biotechnology》2018,60(12):879-886
The transferase activity of non-proofreading DNA polymerases is a well-known phenomenon that has been utilized in cloning and sequencing applications. The non-templated addition of modified nucleotides at DNA blunt ends is a potentially useful feature of DNA polymerases that can be used for selective transformation of DNA 3′ ends. In this paper, we characterized the tailing reaction at perfectly matched and mismatched duplex ends with Cy3- and Cy5-modified pyrimidine nucleotides. It was shown that the best DNA tailing substrate does not have a perfect Watson–Crick base pair at the end. Mismatched duplexes with a 3′ dC were the most efficient in the Taq DNA polymerase-catalysed tailing reaction with a Cy5-modified dUTP. We further demonstrated that the arrangement of the dye residue relative to the nucleobase notably affects the outcome of the tailing reaction. A comparative study of labelled deoxycytidine and deoxyuridine nucleotides showed higher efficiency for dUTP derivatives. The non-templated addition of modified nucleotides by Taq polymerase at a duplex blunt end was generally complicated by the pyrophosphorolysis and 5′ exonuclease activity of the enzyme. 相似文献
998.
Carvalho JE Gomes FR Navas CA 《Journal of comparative physiology. B, Biochemical, systemic, and environmental physiology》2008,178(4):447-456
Anuran amphibians exhibit different patterns of energy substrate utilization that correlate with the intensity of vocal and
locomotor activities. Given the remarkable differences among species in breeding and feeding strategies, and the different
ways energy is used in the whole animal, the suggested correlations between calling and locomotor behavior and the level of
energy substrates in the muscles responsible for such activities are more complex than previously reported. We explored the
relationships between calling and locomotor behavior and energy supply to trunk and hindlimb muscles, respectively, within
the ecologically diverse tree-frog genus Scinax. Specifically, we measured the relative amount of carbohydrates and lipids in these two groups of muscles, and in the liver
of three species of Scinax that differ in vocal and locomotor performance, and compared our results with those of two other species for which comparable
data are available. We also compared the contents of lipids and carbohydrates of conspecific males collected at the beginning
and after 4 h of calling activity. The stomach content to potential feeding opportunities across species was also assessed
in both groups of males. Scinax hiemalis and S. rizibilis exhibit comparatively low and episodic calling during long periods of activity whereas S. crospedospilus calls at higher rates over shorter periods. Male S. hiemalis had highest levels of trunk muscle glycogen followed by those of S. rizilbilis and S. crospedospilus, respectively. There was no correlation between total lipid content in trunk muscle and calling rate among different species,
suggesting that other metabolic aspects may be responsible for the energetic support for vocal activity. The levels of lipids
and carbohydrates in trunk and hindlimb muscles and liver of males collected at the beginning and 4 h into the calling period
were similar across species, so the extent of energetic reserves does not appear to constrain vocal or locomotor activity.
Finally, we found exceptionally high levels of carbohydrates and lipids in the liver of S. rizibilis, a trait perhaps related to a long and demanding breeding period. 相似文献
999.
Bacterial citrate synthase expression and soil aluminum tolerance in transgenic alfalfa 总被引:1,自引:0,他引:1
Barone P Rosellini D Lafayette P Bouton J Veronesi F Parrott W 《Plant cell reports》2008,27(5):893-901
Alfalfa is very sensitive to soil acidity and its yield and stand duration are compromised due to inhibited root growth and
reduced nitrogen fixation caused by Al toxicity. Soil improvement by liming is expensive and only partially effective, and
conventional plant breeding for Al tolerance has had limited success. Because tobacco and papaya plants overexpressing Pseudomonas aeruginosa citrate synthase (CS) have been reported to exhibit enhanced tolerance to Al, alfalfa was engineered by introducing the CS gene controlled by the Arabidopsis Act2 constitutive promoter or the tobacco RB7 root-specific promoter. Fifteen transgenic plants were assayed for exclusion of Al from the root tip, for internal citrate
content, for growth in in vitro assays, or for shoot and root growth in either hydroponics or in soil assays. Overall, only
the soil assays yielded consistent results. Based on the soil assays, two transgenic events were identified that were more
aluminum-tolerant than the non-transgenic control, confirming that citrate synthase overexpression can be a useful tool to
help achieve aluminum tolerance.
Pierluigi Barone and Daniele Rosellini contributed equally to this work. 相似文献
1000.
The Chinese species of the subgenus Microchelonus Szépligeti of the genus Chelonus Panzer with the female carapace having an incised apex in dorsal view and/or in posterior view are revised. Two new species,
Chelonus (Microchelonus) rhagius sp. n. and Chelonus (Microchelonus) tobiasi sp. n. are described. Chelonus (Microchelonus) elegantulus Tobias and Chelonus (Microchelonus) volgensis Tobias are recorded in China for the first time. 相似文献