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51.
Genetic variability in individual troops of the Japanese macaque (Macaca fuscata fuscata) was quantified by the proportion of polymorphic loci and the average heterozygosity per individual from the results of starch-gel electrophoreses of blood proteins controlled by 32 independent genetic loci. The former averaged 9.2% and the latter 1.3%, the values being remarkably lower than those estimated for other animal populations. Geographical distribution of the genetic variations was not uniform in the whole species but the variants occurred only in limited areas. Assuming the selective neutrality of segregating alleles and the two-dimensional stepping-stone model of population structure, the genetic migration rate between the local demes per generation could be estimated to average less than inverse of average effective deme size. Here, the local deme is not a troop itself, but it consists of several troops tightly connected with each other by frequent exchanges of reproductive males. Analyses of correlation between geographic and genetic distances between troops revealed that the gene constitutions of two troops apart more than 100 km on an island could be regarded as practically independent of each other. These results suggest that the population structure of the Japanese macaque species has a tendency to split into a number of local subpopulations in which the effect of random genetic drift is prevailing.  相似文献   
52.
The cerebellar hypoplasia induced by hereditary hyperbilirubinemia in the Gunn rat was analyzed neurochemically and immunohistochemically. The antiserum against myelin basic protein was used to visualize the arborization of the fibers in the cerebellum. Arborization was very scarce in the affected lobes of the homozygous (jj) cerebellum. Na,K-ATPase activity did not show significant differences between the jj and the control (Jj) cerebellum. The concentration of norepinephrine in the jj cerebellum was about 1.5 times that of the control. However, the activation ratio of the Na,K-ATPase by norepinephrine and other catecholamines such as dopamine and isoproterenol was about twice as high as the basal activity, and no significant difference was observed between the jj and the Jj cerebella. The glutamic acid decarboxylase activity of the jj cerebellum did not differ significantly from that of the control.  相似文献   
53.
Abstract: Cerebral cortex from reeler mutant mice was examined morphologically and biochemically. The sequential process of postnatal cell migration in the cerebral cortex of reeler (rl/rl) was examined morphologically. The dense cellular cortical plate lies below the molecular layer near the cerebral surface just after birth in normal mice while in reeler most of the cells are concentrated in the center of the cortex. In the cortex of adult reeler, the broad laminar structure of the neurons could be seen to form inverted positions in the cortical layers. The total wet weight, and the concentration of DNA and RNA in the pallium cerebri from reeler did not differ significantly from those in the control. As to the protein profiles of the pallium cerebri detected by SDS- polyacrylamide gel electrophoresis, no significant differences were observed. Activities of CNPase (2',3'-cyclic nucleotide 3'-phosphohydrolase), which is a myelin enzyme of CNS, and choline acetyltransferase were at the same level in both the reeler and the control. Therefore, reeler mutation does not appear to affect the genetically determined cell numbers, number of cholinergic fibers, and myelination. By autoradiographic observation of the cerebral cortex after intraperitoneal injection of [14C]2-deoxyglucose, it was revealed that 2-deoxyglucose was incorporated intensively into the fourth layer (granular layer) of the cerebrum from the control. In reeler it was also incorporated into the granular layer but in a more widespread distribution. We conclude that terminals to the granular layer make metabolically active synapse, perhaps even in a manner inverted from normal.  相似文献   
54.
The trypsin-catalyzed coupling of bovine (Boc)2-desoctapeptide (B23-B30)-insulin with synthetic octapeptides, H-Gly-X2-X3-X4-Thr-Pro-Lys(Boc)-Thr-OH (X2 = Phe or Ala, X3 = Phe or Ala, X4 = Tyr or Ala), followed by deprotection and purification produced the [AlaB24, ThrB30]-, [AlaB25, ThrB30]-, and [AlaB26, ThrB30]-analogs of bovine insulin in yields of 32, 35, and 32%, respectively. The biological activity of these analogs decreased in the order, normal insulin ([ThrB30]-bovine insulin) = AlaB26-insulin > AlaB25-insulin > AlaB24-insulin, as assayed for receptor binding and some other biological effects, in contrast with the corresponding Leu-analogs of human insulin, in which the activity decreased in the order, normal insulin > LeuB24-insulin > LeuB25-insulin. The affinity to insulin antibodies greatly diminished in both AlaB24-insulin and LeuB24-insulin but not in the B25-substituted analogs. The CD spectra of the Leu- and the Ala-analogs were compared with those of normal insulins to show that no apparent correlation seems to exist between the decrease in biological activity and the conformational changes observed in solution. The effects of organic solvents on the peptide-bond equilibrium and on the stability of trypsin are also discussed.  相似文献   
55.
56.
The thermodynamic parameters of the CO-equilibria of isolated chains of hemoglobin A and of two α-chains in hemoglobins M Milwaukee-I and Saskatoon at 25°, pH 7.0 were determined. The parameters for the binding of the first CO molecule to the hemoglobins M were ΔH′=?17 and ?18 kcal/mole heme and ΔS′=?30 and ?29 e.u. for hemoglobins M Milwaukee-I and Saskatoon, respectively. In contrast to this the characteristics of the second step of the binding were ΔH′=+5.9· and +4.3 kcal/mole and ΔS′=+51 and +49 e.u. These values for the second step were also significantly different from those of the isolated α-chain (ΔH′=?15 kcal/mole and ΔS′=?11 e.u.).  相似文献   
57.
Genetic variation at the locus controlling A1 band of erythrocyte esterase was found in the Japanese macaque,Macaca fuscata. Existence of four alleles,Es-A 1 1 ,Es-A 1 2 ,Es-A 1 3 , andEs-A 1 4 , controlling the mobility of the band and codominance relation between them were postulated. A majority of the troops examined were monomorphic inEs-A 1 1-1 phenotype, and the variant phenotypes were observed to occur only in Yugawara-Ihama, Arashiyama, and Koshima areas.  相似文献   
58.
59.
Taxonomy Plantago asiatica mosaic virus belongs to the genus Potexvirus in the family Alphaflexiviridae of the order Tymovirales.Virion and genome propertiesPlantago asiatica mosaic virus (PlAMV) has flexuous virions of approximately 490–530 nm in length and 10–15 nm in width. The genome of PlAMV consists of a single‐stranded, positive‐sense RNA of approximately 6.13 kb. It contains five open reading frames (ORFs 1–5), encoding a putative viral polymerase (RdRp), movement proteins (triple gene block proteins, TGBp1‐3), and coat protein (CP), respectively.Host rangePlAMV has an exceptionally wide host range and has been isolated from various wild plants, including Plantago asiatica, Nandina domestica, Rehmannia glutinosa, and other weed plants. Experimentally PlAMV can infect many plant species including Nicotiana benthamiana and Arabidopsis thaliana. It also infects ornamental lilies and frequently causes severe necrotic symptoms. However, host range varies depending on isolates, which show significant biological diversity within the species.Genome diversityPlAMV can be separated into five clades based on phylogenetic analyses; nucleotide identities are significantly low between isolates in the different clades.TransmissionPlAMV is not reported to be transmitted by biological vectors. Virions of PlAMV are quite stable and it can be transmitted efficiently by mechanical contact.Disease symptomsPlAMV causes red‐rusted systemic necrosis in ornamental lilies, but it shows much weaker, if any, symptoms in wild plants such as P. asiatica.ControlControl of the disease caused by PlAMV is based mainly on rapid diagnosis and elimination of the infected bulbs or plants.  相似文献   
60.
L-阿拉伯糖异构酶(L-arabinose isomerase,L-AI)是一种可以催化D-半乳糖为D-塔格糖的胞内异构化酶。随着塔格糖在食品工业中越来越广泛的应用,能够将半乳糖转化为塔格糖的食品级微生物以及食品级来源的L-AI受到更大的关注。文中从各种酸奶制品、泡菜及其他一些食品中采集不同的样品,筛选出1株具有L-AI酶活的食品级菌株,经过生理生化鉴定以及16S rDNA序列测定,确定该菌株为戊糖片球菌,命名为Pediococcus pentosaceus PC-5。以该菌基因组为模板,克隆L-AI基因,并在大肠杆菌BL21成功地异源表达。表达产物经粗提取后,在40℃下加入Mn2+,使D-半乳糖转化为D-塔格糖的转化率为33%。  相似文献   
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