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941.
摘要 目的:探究血栓分子标志物[血栓调节蛋白(TM)、凝血酶-抗凝血酶Ⅲ复合物(TAT)、纤溶酶-α2纤溶酶抑制剂复合物(PIC)、组织型纤溶酶原激活剂-抑制剂1复合物(t-PAIC)]与急性缺血性脑卒中(AIS)病情严重程度及溶栓预后的相关性。方法:选取2020年 7月至2022年6月我院神经内科收治的AIS患者120例为研究组,根据患者NIHSS评分为轻症组(n=48)、中症组(n=52)及重症组(n=20);NIHSS评分升高组(n=50)和降低组(n=70)。同期选择我院查体中心查体的健康人群为对照组(n=30)。对比观察组和对照组、不同严重程度和不同预后患者外周血血栓分子标志物水平差异。采用Pearson相关分析法分析AIS患者外周血血栓分子标志物水平与病情严重程度及预后的相关性。利用ROC曲线评估外周血血栓分子标志物水平对AIS患者预后的预测价值。结果:AIS组患者外周血TM、TAT、PIC及t-PAIC水平明显高于对照组,差异有统计意义(P<0.01)。重症组患者外周血TM、TAT、PIC及t-PAIC水平明显高于中症组及轻症组,中症组患者血清TM、TAT、PIC及t-PAIC水平明显高于轻症组,差异有统计意义(P<0.01)。NIHSS评分升高组患者外周血TM、TAT、PIC及t-PAIC水平明显高于NIHSS评分降低组,差异有统计意义(P<0.01)。外周血TM、TAT、PIC及t-PAICt水平与NIHSS评分呈正相关(r分别为0.326、0.513、0.124和0.417,P均<0.05)。外周血TM、TAT、PIC及t-PAIC水平预估AIS患者预后的AUC 分别为 0. 737,0.850,0.762和0.712。其中TAT预估AIS患者预后的AUC、敏感度和特异性均最高。结论:AIS患者外周血TM、TAT、PIC及t-PAIC水平明显高于健康人群,可随病情严重程度及预后情况的变化而变化,其在病情评估及溶栓预后预测中具有指导价值。  相似文献   
942.
The development of multipurpose crops will drive the transformation of agricultural “waste” into added-value products, helping to meet biomass demands without competing with food production or increasing environmental pressure. Lupinus mutabilis, has been proposed not only as a valid source of protein and oil for Europe but also as a possible source of lignocellulosic feedstock for the biorefinery industry. In this study, the quality of L. mutabilis lignocellulosic biomass and its genetic architecture are investigated for the first time, using a panel of 223 accessions planted across three locations in two different European cropping conditions. Biomass quality was evaluated based on the estimation of neutral detergent fiber, cellulose, hemicellulose and acid detergent lignin fractions, and on the basis of the monosaccharide composition of cell wall polysaccharides. The broad variation in yield and composition of biomass encountered in the panel confirms the potential of L. mutabilis as lignocellulosic feedstock and points out the value of this panel as a breeding tool for the improvement of biomass quality. A genome-wide association study was conducted to identify single-nucleotide polymorphisms (SNPs) associated with biomass quality, both across locations and per specific location. Scanning of 16,781 SNPs across the whole genome identified 46 unique quantitative trait loci for biomass quality, 4 of which were detected as common either among traits or GWAS models. For each of the traits analyzed, between 3 and 10 SNPs were detected, explaining 2.7%–15.9% of the phenotypic variation. Underlying these loci, 28 genes were proposed as candidate genes for biomass quality. Important genes involved in cellulose and sucrose synthesis (CESA4, SPP1,WRKY33, GONST2), monolignol biosynthesis (SKIP31, WAT1, CCR-SNL6) and pectin degradation (RAV1, PE) were identified and will require validation to confirm their value for application in L. mutabilis breeding.  相似文献   
943.
The electrophoretic patterns of 15 protein systems codified for 20 genetic loci were investigated using horizontal electrophoresis. A total of 150 blood samples, from five species of the genusCallithrix were analyzed. Polymorphic variation was observed in 10 out 20 loci analyzed. The genotypic distributions are in Hardy-Weinberg equilibrium. The average heterozygosity (H) varied from 1% to 5%, similar to those observed for other Neotropical primates. The genetic distance coefficients revealed a phylogenetic separation of these species into two groups: (1) “argentata” (C. humeralifer andC. emiliae); (2) “jacchus” (C. jacchus, C. penicillata, andC. geoffroyi). This arrangement is according to the taxonomic arrangement proposed byHershkovitz (1977),de Vivo (1988), andMittermeier et al. (1988). The results in each group are compatible with the subspecies values recorded for the Platyrrhini. These values showed that:C. humeralifer andC. emiliae are subspecies ofC. argentata;C. jacchus, C. penicillata, andC. geoffroyi are subspecies ofC. jacchus. These results also suggest thatC. j. geoffroyi is the “jacchus” group taxon, most similar genetically to the “argentata” group.  相似文献   
944.
Summary The effect of 3′methyl-4-dimethylaminoazobenzene (3′-Me-DAB) in the induction of malignant transformation and of 8-azaguanine-resistant mutations and chromosomal aberrations was studied in a diploid strain derived from normal rat liver cells. The cells were malignantly transformed by treatment with 3′-Me-DAB 1.7 μg/ml for 130 to 221 d or 1.7 μg/ml for 53 d followed by 24.9 μg/ml for 27 to 77 d. The untreated control cells did not transform spontaneously until the 232nd d in culture. Some properties of the 3′-Me-DAB-treated cells were compared to those of untreated control cells but no reliable marker for predicting the tumorigenic potential of the cells was found. The single addition of 3′-Me-DAB caused little induction of 8-azaguanine-resistant mutations and chromosomal aberrations to the cells. However, mutations and chromosomal aberrations were significantly induced byN-acetoxy-4-methylaminoazobenzene, an active metabolite of 4-dimethylaminoazobenzene or 3′-Me-DAB in the presence of liver microsomes. This study was supported by a grant for cancer research from the Japanese Ministry of Education.  相似文献   
945.
The gastrodermal Golgi apparatus of adult Schistosoma mansoni displays two distinct morphologies. In one type, there is an identifiable cis (forming) face where vesicles from the endoplasmic reticulum fuse to form the cisternae. A morphological change occurs in the cisternae as the trans (emitting) face is approached with the cisternae becoming progressively flattened. The cisternae at the emitting face produce a membrane-bound secretory granule with moderately electron-dense contents and a vacuolar structure that may be analogous to a condensing vacuole as reported in several vertebrate secretory cells. In a second type, vesicles possessing a thicker membrane than those of the transfer vesicles are observed at the emitting face. They are not observed when the secretory granules are present. Several cytochemical markers were used to aid in studying the polarity of the Golgi apparatus. Enzymes studied were thiamine pyrophosphatase (TPPase) (EC 3.6.1.1), nucleoside diphosphatase (NDPase) (EC 3.6.1.6) using uridine diphosphate as a substrate, and nicotinamide adenine dinucleotide phosphatase (NADPase) (EC 3.1.3.2). Reaction products from all enzyme markers were observed in the cisternae and, to some extent, in the transfer vesicles. At times, NADPase and TPPase reaction products were observed in all cisternae and in the transfer vesicles of the Golgi. When this distribution was evident, the latter vesicles were observed in clusters occasionally fusing with lipid-like globules dispersed throughout the gastrodermis. Heterogeneity in cisternae was observed when NDPase, TPPase, and osmium reduction techniques were used. NDPase activity was limited to the middle cisternae while reduced osmium was observed in the outer two cisternae and in some transfer vesicles. TPPase reaction product was also observed in the secretory granules and in the condensing vacuoles. It is hypothesized that a functional bipolarity may be demonstrated by the Golgi. Under certain stress conditions, the forming face of the Golgi may package lysosomal enzymes while the emitting region of the Golgi appears to be responsible for the packaging of the secretory granules. The fusion of transfer vesicles and, at times, secretory granules with lipid-like globules is postulated to represent a mechanism by which enzymes may be transported to the lumen of the cecum.  相似文献   
946.
Two separate, independent experiments were conducted to evaluate the effect of 60 Hz linearly polarized, sinusoidal, continuous-wave magnetic fields (MFs) on immune system performances in rats born and raised under these fields. Each experiment lasted for 6 weeks. A total of 96 animals, divided into groups of eight animals each, was exposed for 20 h/day to MFs of different intensities, i.e., sham (<0.02 μT) and 2, 20, 200, and 2000 μT. Another group of animals, which was housed in a separate room, served as cage controls (CC). These animals were exposed to ambient MFs of <0.02 μT. The following immune responses were evaluated in both experiments: total T and B cells; CD4+ and CD8+ subpopulation and natural killer (NK) cell activity in splenic lymphocytes; hydrogen peroxide (H2O2), nitrous oxide (NO), and tumor necrosis factor (TNF) production by peritoneal macrophages. Our results show that a 6 week exposure to MFs induced a significant decrease in the number of CD5+, CD4+, and CD8+ populations. These changes were even more significant in rats that were exposed to fields of 2000 μT. A lower, although significant, decrease in the CD5+ population was also observed in animals that were exposed to fields of 200 μT. Linear regression analysis demonstrated a dose effect with MF intensity. B lymphocyte (Ig+ cell) populations also showed a 12% decrease (P < .05) in the groups that were exposed to fields of 20 and 200 μT. However, these results were not significant, and no relation with MF intensities could be demonstrated. In contrast, evaluation of splenic NK cell activity revealed a 50% increase (P < .05) in animals that were exposed to fields of 2000 μT. No significant results were obtained from the evaluation of TNF activity and NO secretion in peritoneal macrophages. Phorbol 12-myristate 13-acetate (PMA)-stimulated and net H2O2 productions for a minor subpopulation of peritoneal cells showed positive dose-response correlations by linear regression analysis. Taken together, our results suggest that an in vivo exposure of rats for 6 weeks to 60 Hz MFs can induce significant immunological perturbations on effector cells of both natural and adaptive immunity in a dose-dependent fashion. © 1996 Wiley-Liss, Inc.  相似文献   
947.
The rat pheochromocytoma cell line PC12 contains two distinct pathways of protein secretion. Proteins secreted via the regulated pathway are stored in secretory vesicles and exocytosed only in response to a specific signal, whereas proteins secreted via the constitutive pathway are exported continuously. Analysis of regulated secretion of a heterologous protein in this system often relies on comparison of secretion rates with those of endogenous proteins known to be secreted via the constitutive route. In order to improve these controls, we have evaluated a number of secreted enzymes, selected for the sensitivity and convenience of their assays, as transgenic markers for the constitutive pathway. We show that both human-secreted placental alkaline phosphatase (SEAP) and bacterial β-lactamase operate in this way in transfected PC12 cells. In contrast, transfected human tissue plasminogen activator (tPA) is shown to be sorted to the regulated pathway.  相似文献   
948.
 Two independent F2 populations of Lycopersicon esculentum×L. pennellii which have previously been investigated in RFLP mapping studies were used for construction of a highly saturated integrated AFLP map. This map spanned 1482 cM and contained 67 RFLP markers, 1078 AFLP markers obtained with 22 EcoRI+MseI primer combinations and 97 AFLP markers obtained with five PstI+MseI primer combinations, 231 AFLP markers being common to both populations. The EcoRI+MseI AFLP markers were not evenly distributed over the chromosomes. Around the centromeric region, 848 EcoRI+ MseI AFLP markers were clustered and covered a genetic distance of 199 cM, corresponding to one EcoRI+ MseI AFLP marker per 0.23 cM; on the distal parts 1283 cM were covered by 230 EcoRI+MseI AFLP markers, corresponding to one marker per 5.6 cM. The PstI/MseI AFLP markers showed a more even distribution with 16 PstI/MseI AFLP markers covering a genetic distance of 199 cM around the centromeric regions and 81 PstI/MseI AFLP markers covering a genetic distance of 1283 cM on the more distal parts, corresponding to one marker per 12 and 16 cM respectively. In both populations a large number of loci showed a significant skewed segregation, but only chromosome 10 loci showed skewness that was similar for both populations. This ultra-dense molecular-marker map provides good perspectives for genetic and breeding purposes and map-based cloning. Received: 3 September 1998 / Accepted: 27 October 1998  相似文献   
949.
A chromosomal region originating from Malus floribunda 821 confers Vf scab resistance to many isolates of Venturia inaequalis. Twelve DNA markers located in this region were used to scan the equivalent of 31 cM in 98 Malus accessions. This allowed a molecular diagnosis of a source of resistance in apple germplasm with the aid of pedigree information, and in the context of a limited marker survey representing other chromosomes. At least five marker alleles were present in all scab-resistant breeding selections or varieties arising from M. floribunda. The validity of findings based on RAPD markers was confirmed with SCAR assays and Southern-hybridisation experiments. The order of markers determined in previous mapping studies was confirmed and sets of recombinants identified that establish reliable fine-mapping orders within 0.7 cM of the resistance locus. None of the marker alleles were present in the accessions that are either susceptible or possess weak polygenic resistance to scab. The presence of some alleles corresponding to those present at least 5.3 cM from Vf in M. floribunda was detected in some accessions. Other major sources of scab resistance do not appear to possess alleles in common with the Vf region, which will simplify future allelism tests. The results are discussed in the context of the introgression of resistance loci together with marker-assisted selection. The use of breeding pedigrees to assist in fine-scale mapping and map-based cloning is discussed. Received: 16 February 1999 / Accepted: 11 March 1999  相似文献   
950.
 A common problem in mapping quantitative trait loci (QTLs) is that marker data are often incomplete. This includes missing data, dominant markers, and partially informative markers, arising in outbred populations. Here we briefly present an iteratively re-weighted least square method (IRWLS) to incorporate dominant and missing markers for mapping QTLs in four-way crosses under a heterogeneous variance model. The algorithm uses information from all markers in a linkage group to infer the QTL genotype. Monte Carlo simulations indicate that with half dominant markers, QTL detection is almost as efficient as with all co-dominant markers. However, the precision of the estimated QTL parameters generally decreases as more markers become missing or dominant. Notable differences are observed on the standard deviation of the estimated QTL position for varying levels of marker information content. The method is relatively simple so that more complex models including multiple QTLs or fixed effects can be fitted. Finally, the method can be readily extended to QTL mapping in full-sib families. Received: 16 June 1998 / Accepted: 29 September 1998  相似文献   
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