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31.
Although administration of androstenediol (a metabolite of dehydroepiandrosterone) following trauma-hemorrhage (T-H) produces beneficial effects on inflammatory cytokines and organ function, it remains unknown whether this metabolite has any salutary effects in preventing alterations in immune cell cytokine production following a combined insult of T-H and sepsis. To examine this, male rats underwent laparotomy, hemorrhagic shock (mean BP 40 mmHg for 90 min) and resuscitation or sham operation. Androstenediol (1 mg/kg BW i.v.) or vehicle was administered at the end of resuscitation. Twenty hrs after T-H or sham operation, sepsis was induced by cecal ligation and puncture (CLP). Five hours thereafter, plasma cytokine levels and cytokine production of various immune cells were determined. In a separate set of experiments, survival was monitored for 10 days after the induction of sepsis. Administration of androstenediol markedly decreased plasma IL-6 and TNF-alpha levels following T-H and CLP. Furthermore, it prevented the increased production of IL-6 and TNF-alpha by Kupffer cells and alveolar macrophages and attenuated the decrease in IL-6 and TNF-alpha production by splenic macrophages; however, it had no significant effects on the depressed IL-6 and TNF-alpha production by PBMC following T-H and CLP. The depressed IL-2 and IFN-gamma production by splenocytes under those conditions was attenuated by the administration of androstenediol. Furthermore, survival rate following T-H and subsequent sepsis was improved by androstenediol treatment. Since androstenediol administration following T-H attenuated cytokine production and reduced mortality in a double-hit model of T-H and sepsis, this agent appears to be a novel and useful adjunct for maintaining the immune cell functions following T-H and for decreasing the mortality rate from subsequent susceptibility to sepsis. 相似文献
32.
Repression of tax expression is associated both with resistance of human T-cell leukemia virus type 1-infected T cells to killing by tax-specific cytotoxic T lymphocytes and with impaired tumorigenicity in a rat model 总被引:2,自引:0,他引:2 下载免费PDF全文
Nomura M Ohashi T Nishikawa K Nishitsuji H Kurihara K Hasegawa A Furuta RA Fujisawa J Tanaka Y Hanabuchi S Harashima N Masuda T Kannagi M 《Journal of virology》2004,78(8):3827-3836
Human T-cell leukemia virus type 1 (HTLV-1) causes adult T-cell leukemia (ATL). Although the viral transactivation factor, Tax, has been known to have apparent transforming ability, the exact function of Tax in ATL development is still not clear. To understand the role of Tax in ATL development, we introduced short-interfering RNAs (siRNAs) against Tax in a rat HTLV-1-infected T-cell line. Our results demonstrated that expression of siRNA targeting Tax successfully downregulated Tax expression. Repression of Tax expression was associated with resistance of the HTLV-1-infected T cells to Tax-specific cytotoxic-T-lymphocyte killing. This may be due to the direct effect of decreased Tax expression, because the Tax siRNA did not alter the expression of MHC-I, CD80, or CD86. Furthermore, T cells with Tax downregulation appeared to lose the ability to develop tumors in T-cell-deficient nude rats, in which the parental HTLV-1-infected cells induce ATL-like lymphoproliferative disease. These results indicated the importance of Tax both for activating host immune response against the virus and for maintaining the growth ability of infected cells in vivo. Our results provide insights into the mechanisms how the host immune system can survey and inhibit the growth of HTLV-1-infected cells during the long latent period before the onset of ATL. 相似文献
33.
Hideyuki Kawabata Taro Katsura Eiji Kondo Nobuto Kitamura Shin Miyatake Yoshie Tanabe Takao Setoguchi Setsuro Komiya Kazunori Yasuda 《Journal of biomechanics》2009,42(15):2611-2615
The effect of stress deprivation on the tendon tissue has been an important focus in the field of biomechanics. However, less is known about the in vivo effect of stress deprivation on fibroblast apoptosis as of yet. This study was conducted to test a hypothesis that complete stress deprivation of the patellar tendon induces fibroblast apoptosis in vivo with activation of Jun N-terminal kinase (JNK) and p38 mitogen-activated protein kinase (p38) within 24 h after treatment. A total of 35 mature rabbits were divided into stress-shielded (n=15), sham-operated (n=15), and control (n=5) groups. To completely shield the patellar tendon from stress, we used an established surgical method. Animals were sacrificed at 24 h, and 2, 4, 7, and 14 days after the treatment. Tendon specimens underwent TUNEL assay and immunohistological examinations of active caspase-3, JNK, and p38. Both the number and the ratio of TUNEL-positive and caspase-3-positive cells were significantly greater (p<0.0001) in the stress-shielded group than in the sham group at 24 h, 2, 4, and 7 days. Concerning JNK and p38, both the number and the ratio were significantly greater (p<0.0001) in the stress-shielded group than in the sham group at 24 h, 2, and 4 days. This study demonstrated that complete stress deprivation induces fibroblast apoptosis in vivo with activation of JNK and p38 within 24 h. This fact suggested that the fibroblast apoptosis caused by stress deprivation is induced via the mitogen-activated protein kinase signaling pathway. 相似文献
34.
Summary To determine both a threshold value of calcium concentration (CC) for the release of storage granules and that for the acceleration of degradation of these granules, the rat parathyroid glands were perfused in situ with HEPES-Ringer solutions containing different concentration of Ca2+ for 10 min. With perfusates containing 0.83–1.21 mM Ca2+ (equivalent to 8–11 mg/dl serum calcium), the number of type-I storage granules (large core) [NSG-I] and that of type-II storage granules (small core) [NSG-II] remained unchanged. With perfusates containing 0.83 mM Ca2+ (7.5 mg/dl) or less, however, both NSG-I and NSG-II decreased remarkably and the former was larger than the latter. On the contrary, with perfusates containing 1.27 mM Ca2+ (11.5 mg/dl) or more, NSG-II increased and the ratio of NSG-I to NSG-II was changed reversely. We concluded that a thereshold value of CC required for the release of storage granules may be present between 0.88 and 0.83 mM Ca2+ (8 and 7.5 mg/dl) and that a threshold value of CC for accelerating the transformation of type-I granules into type-II, the degradation of storage granules, may be situated at about 1.27 mM Ca2+ (11.5 mg/dl). Additionally, it was suggested that both prosecretory and storage granules are not only formed at the innermost Golgi cisterna but also at the trans-Golgi network. 相似文献
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Yukio Furuichi Takao Takahashi Katsumi Imaizumi Michihiro Sugano 《Bioscience, biotechnology, and biochemistry》2013,77(7):1777-1781
The absorbability of polyethylene glycol (PEG), a water-soluble nutritional marker, from the gastrointestinal tract of rat was examined using the [14C]-labeled compound ([14C]PEG) having a molecular weight of 4000. Intravenously injected [14C]PEG was readily excreted and recovered almost completely in the urine and neither hepatic nor renal uptake of the PEG was observed. Intragastrically administered [14C]PEG was eliminated in the urine with an average recovery of only 0.43 ± 0.13% (Mean ± S.D., n= 10) of the dose over 24 hr. From the gel column chromatographic profile of the radioactivity excreted in the urine after an oral dose, [14C]PEG was suggested to be absorbed in two forms, as an original form and as a low molecular weight component. The latter component might be the degraded product of PEG in the gastrointestinal tract. From these results it was confirmed that PEG with a molecular weight of 4000 is a satisfactory marker because of its low absorbability. 相似文献
38.
Recovery of uranium by immobilized microorganisms 总被引:2,自引:0,他引:2
Akira Nakajima Takao Horikoshi Takashi Sakaguchi 《Applied microbiology and biotechnology》1982,16(2-3):88-91
Summary Some attempts were made to recover uranium from sea and fresh water using immobilized Streptomyces viridochromogenes and Chlorella regularis cells. The cells immobilized in polyacrylamide gel have the most favorable features for uranium recovery; high adsorption ability, good mechanical properties, and applicability in a column system. The adsorption of uranium by the immobilized cells is not affected by the pH values between 4 and 9. These results show that uranium adsorption becomes independent of pH after immobilization. The amounts of uranium adsorbed by the immobilized cells increased linearly with temperature, suggesting that the adsorption of uranium by the immobilized cells is an endothermic reaction. The immobilized cells can recover uranium almost quantitatively from both fresh and sea water containing uranium, and almost all uranium adsorbed is desorbed with a solution of Na2CO3. Thus the immobilized cells of Streptomyces and Chlorella can be used repeatedly in adsorption-desorption process.Studies on the Accumulation of Heavy Metal Elements in Biological Systems. XXI 相似文献
39.
Reaction of methyl α-d-glucopyranoside and methyl α-d-mannopyranoside with alkaline hydrogen peroxide and a ferrous salt, at room temperature and below, afforded the corresponding d-glycosiduronic acids. On dehydration, the acids gave the corresponding gamma lactones, with a shift of the pyranoid ring to a furanoid ring. Surprisingly, the glycosidic methyl group was retained during the oxidation reactions and pyranose-furanose interconversions. This retention is rationalized by a mechanism involving formation of a pseudo-acyclic intermediate. Another unexpected reaction was the conversion of slightly moist methyl d-glucopyranosiduronolactone syrup, on standing for 5–6 days at room temperature, into crystalline d-glucofuranurono-6,3-lactone, and of methyl α-d-mannopyranosidurono-6,3-lactone into crystalline d-mannofuranurono-6,3-lactone. 相似文献
40.
Marko-Varga G Ogiwara A Nishimura T Kawamura T Fujii K Kawakami T Kyono Y Tu HK Anyoji H Kanazawa M Akimoto S Hirano T Tsuboi M Nishio K Hada S Jiang H Fukuoka M Nakata K Nishiwaki Y Kunito H Peers IS Harbron CG South MC Higenbottam T Nyberg F Kudoh S Kato H 《Journal of proteome research》2007,6(8):2925-2935
Personalized medicine allows the selection of treatments best suited to an individual patient and disease phenotype. To implement personalized medicine, effective tests predictive of response to treatment or susceptibility to adverse events are needed, and to develop a personalized medicine test, both high quality samples and reliable data are required. We review key features of state-of-the-art proteomic profiling and introduce further analytic developments to build a proteomic toolkit for use in personalized medicine approaches. The combination of novel analytical approaches in proteomic data generation, alignment and comparison permit translation of identified biomarkers into practical assays. We further propose an expanded statistical analysis to understand the sources of variability between individuals in terms of both protein expression and clinical variables and utilize this understanding in a predictive test. 相似文献