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891.
Etsuro Sugimoto Naofumi Takahashi Yasuo Kitagawa Hideo Chiba 《Bioscience, biotechnology, and biochemistry》2013,77(10):2063-2070
Various physiological roles of mammalian aldehyde dehydrogenase had been anticipated because of its broad substrate specificity. In order to clarify roles of the enzyme and the regulation of aldehyde metabolisms in liver, the intracellular distribution and isozyme of beef liver aldehyde dehydrogenase were studied.The presence of the mitochondrial, the microsomal and the cytoplasmic isozymes were proved by the isoelectric focusing. These isozymes were different from each other in pH-activity curve in the responces for steroid hormones and disulfiram.It was suggested by comparing the reactivities of these isozymes for various aldehydes that particular aldehyde might be oxidized by a favorite isozyme at particular locality in the liver cells and that a share of physiological role among these isozymes is probable. 相似文献
892.
《Bioscience, biotechnology, and biochemistry》2013,77(8):1898-1903
From the methanol extract of boron deficient Olea europaea leaves, two secoiridoid glycosides, not detected in leaf extracts of untreated plants, 6′-E-p-coumaroyl-secologanoside and 6′-O-[(2E)-2,6-dimethyl-8-hydroxy-2-octenoyloxy]-secologanoside, were isolated together with three known secoiridoid glycosides, oleuropein, oleoside dimethyl ester, and secologanoside. The structures of the isolated compounds were established by means of NMR and MS spectral analyses. The above novel secoiridoids were synthesized by the plant as a physiological response to nutrient stress. 相似文献
893.
894.
Markham AC Gesquiere LR Bellenger JP Alberts SC Altmann J 《American journal of primatology》2011,73(11):1160-1168
In immature wild savannah baboons (Papio cynocephalus), we observed symptoms consistent with copper (Cu) deficiency and, more specifically, with a disorder referred to as white monkey syndrome (WMS) in laboratory primates. The objectives of this study were to characterize this pathology, and test three hypotheses that (1) Cu deficiency may have been induced by zinc (Zn) toxicity, (2) it may have been induced by molybdenum (Mo) toxicity, and (3) cumulative rainfall during the perinatal period and particularly during gestation is an ecological factor distinguishing infants afflicted with WMS from non-WMS infants. During 2001-2009, we observed 22 instances of WMS out of a total 377 live births in the study population. Visible symptoms exhibited by WMS infants included whitening of the animal's fur and/or impaired mobility characterized by an apparent "stiffening" of the hindlimbs. Occurrence of WMS did not vary significantly by gender. However, among individuals that survived at least 180 days, WMS males had a significantly lower survivorship probability than non-WMS males. Zn/Cu ratios assessed from hair samples of adult female baboons were higher in females who had produced at least one WMS offspring relative to females who had not had a WMS offspring. This was true even when the hair sample was collected long after the birth of the female's afflicted infant. We consider this potentially indicative of a robust tendency for low Cu levels induced by elevated Zn intake in some individuals. No significant differences of Mo/Cu ratios were observed. Cumulative rainfall during gestation (~179 days) was 50% lower for WMS infants relative to non-WMS infants. In contrast, rainfall for the two classes of infants did not differ in the 180 days before conception or in the 180 days following birth. This finding highlights the importance of prenatal ecological conditions in healthy fetal development with regard to WMS. 相似文献
895.
It has been shown that marine algae produce the compatible solute dimethylsulfoniopropionate (DMSP) from methionine (Met) via four enzymatic reactions in which the third step, synthesis of 4‐dimethylsulfonio‐2‐hydroxy‐butyrate (DMSHB) from 4‐methylthio‐2‐hydroxybutyrate (MTHB), is the committing step. However, regulation of the biosynthetic pathways and transport properties of DMSP is largely unknown. Here, the effects of sulfur and sodium concentrations on the uptake and synthesis of DMSHB and DMSP were examined in a sterile mutant of Ulva pertusa Kjellm. Sulfur deficiency increased the activity of the sulfur assimilation enzyme O‐acetyl serine sulfhydrylase but decreased the MTHB S‐methyltransferase activity, suggesting the preferential utilization of sulfur atoms for Met metabolites other than DMSP. Uptake of DMSP and DMSHB was enhanced by S deficiency. High salinity enhanced the MTHB S‐methyltransferase activity as well as the uptake of DMSHB. The MTHB S‐methyltransferase activity was inhibited by its product DMSP. These data demonstrate the importance of MTHB S‐methyltransferase activity and uptake of DMSHB for the regulation of DMSP. 相似文献
896.
摘要 目的:观察益肾活血解毒汤治疗肾虚血瘀型颈动脉粥样硬化(CAS)效果。方法:选取我院2021年8月~2023年4月收治的肾虚血瘀型CAS患者80例,随机分为观察组和对照组,各40例。两组均予以常规西医治疗,观察组加服益肾活血解毒汤,治疗周期为四周。观察两组的临床疗效、血脂等指标变化,并进行统计学比较。结果:两组治疗前中医证候积分无差异(P>0.05),而治疗后,观察组中医证候积分明显低于对照组(P<0.05);观察组总有效率(97.50%)虽在数值上高于对照组(92.50%),但并无统计学意义(P>0.05);相较于治疗前,两组治疗后血脂指标(CHOL、TG、LDL-C)和炎性因子(NLRP3、Caspase-1、IL-1β、IL-18)水平显著下降(P<0.05),而观察组下降幅度更大,与对照组差异显著(P<0.05);服药期间,两组均无明显不良反应发生。结论:常规调脂抗动脉粥样硬化联合益肾活血解毒汤治疗肾虚血瘀型CAS疗效肯定,可有效改善临床症状,调节血脂水平,控制炎症反应,且安全性良好。 相似文献
897.
898.
Pham CA Jung SJ Phung NT Lee J Chang IS Kim BH Yi H Chun J 《FEMS microbiology letters》2003,223(1):129-134
A facultative anaerobic bacterium was isolated from a mediator-less microbial fuel cell fed with artificial wastewater containing acetate and designated as PA3. The isolate was identified as a strain of Aeromonas hydrophila based on its biochemical, physiological and morphological characteristics as well as 16S rDNA sequence analysis and DNA-DNA hybridization. PA3 used glucose, glycerol, pyruvate and hydrogen to reduce Fe(III), nitrate and sulfate. Cyclic voltammetry showed that PA3 was electrochemically active and was the culture collection strain A. hydrophila KCTC 2358. Electricity was generated from a fuel cell-type reactor, the anode compartment of which was inoculated with cell suspensions of the isolate or A. hydrophila KCTC 2358. The electrochemical activities are novel characteristics of A. hydrophila. 相似文献
899.
Witkowska D Masłowska E Staniszewska M Szostko B Jankowski A Gamian A 《FEMS immunology and medical microbiology》2006,48(2):205-214
In earlier studies on an animal model we observed protective properties of outer membrane proteins (OMPs) of Shigella, Hafnia, and Escherichia coli strains. In order to investigate human sera for reactivity with OMPs we subjected these proteins to immunoblotting with umbilical cord plasma and sera from children and adults. The IgG and IgA antibodies interacted primarily with a 38-kDa protein, in similar way for several enterobacterial strains, but different for Pseudomonas aeruginosa. This observation prompted us to determine the reactivity with the purified 38-kDa OMP in the sera of several groups of children. The reactivity of the protein from Shigella flexneri serotype 3a with sera in ELISA was age dependent, increasing from low reactivity in infants to the adult antibody level. The IgG and IgA antibody specific response thus revealed the normal pattern of immunity. The level of IgA and IgG antibody was significantly low in child patients with IgA and/or IgG immunoglobulin deficiencies, but was at the healthy control level in children with recurrent respiratory tract inflammation. These data correlated with total IgA and IgG levels in immunoglobulin-deficient children. The results indicate that this protein may serve as an immunodiagnostic marker, but also as an antigen carrier in vaccines. 相似文献
900.