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1.
Walking ability is significantly lower in hemodialysis patients compared to healthy people. Decreased walking ability characterized by slow walking speed is associated with adverse clinical events, but determinants of decreased walking speed in hemodialysis patients are unknown. The purpose of this study was to identify factors associated with slow walking speed in ambulatory hemodialysis patients. Subjects were 122 outpatients (64 men, 58 women; mean age, 68 years) undergoing hemodialysis. Clinical characteristics including comorbidities, motor function (strength, flexibility, and balance), and maximum walking speed (MWS) were measured and compared across sex-specific tertiles of MWS. Univariate and multivariate logistic regression analyses were performed to examine whether clinical characteristics and motor function could discriminate between the lowest, middle, and highest tertiles of MWS. Significant and common factors that discriminated the lowest and highest tertiles of MWS from other categories were presence of cardiac disease (lowest: odds ratio [OR] = 3.33, 95% confidence interval [CI] = 1.26–8.83, P<0.05; highest: OR = 2.84, 95% CI = 1.18–6.84, P<0.05), leg strength (OR = 0.62, 95% CI = 0.40–0.95, P<0.05; OR = 0.57, 95% CI = 0.39–0.82, P<0.01), and standing balance (OR = 0.76, 95% CI = 0.63–0.92, P<0.01; OR = 0.81, 95% CI = 0.68–0.97, P<0.05). History of fracture (OR = 3.35, 95% CI = 1.08–10.38; P<0.05) was a significant factor only in the lowest tertile. Cardiac disease, history of fracture, decreased leg strength, and poor standing balance were independently associated with slow walking speed in ambulatory hemodialysis patients. These findings provide useful data for planning effective therapeutic regimens to prevent decreases in walking ability in ambulatory hemodialysis patients.  相似文献   
2.
Whole cells of Chlorella vulgaris and Clostridium butyricum were co-immobilized in 2% agar gel. NADP was suitable as an electron carrier. The rate of hydrogen evolution increased with increasing NADP concentration. The optimum conditions for hydrogen evolution were pH 7.0 and 37°C. The immobilized C. vulgaris-NADP-immobilized Cl. butyricum system continuously evolved hydrogen at a rate of 0.29–1.34 μmol/h per mg Chl for 6 days. On the other hand, the system without NADP evolved only a trace amount of hydrogen.  相似文献   
3.
Compression wood (CW) contains higher quantities of β-1-4-galactan than does normal wood (NW). However, the physiological roles and ultrastructural distribution of β-1-4-galactan during CW formation are still not well understood. The present work investigated deposition of β-1-4-galactan in differentiating tracheids of Cryptomeria japonica during CW formation using an immunological probe (LM5) combined with immunomicroscopy. Our immunolabeling studies clearly showed that differences in the distribution of β-1-4-galactan between NW (and opposite wood, OW) and CW are initiated during the formation of the S1 layer. At this stage, CW was strongly labeled in the S1 layer, whereas no label was observed in the S1 layer of NW and OW. Immunogold labeling showed that β-1-4-galactan in the S1 layer of CW tracheids significantly decreased during the formation of the S2 layer. Most β-1-4-galactan labeling was present in the outer S2 region in mature CW tracheids, and was absent in the inner S2 layer that contained helical cavities in the cell wall. In addition, delignified CW tracheids showed significantly more labeling of β-1-4-galactan in the secondary cell wall, suggesting that lignin is likely to mask β-1-4-galactan epitopes. The study clearly showed that β-1-4-galactan in CW was mainly deposited in the outer portion of the secondary cell wall, indicating that its distribution may be spatially consistent with lignin distribution in CW tracheids of Cryptomeria japonica.  相似文献   
4.
1. Stomachs of adult teleosts and elasmobranchs reacted to an anti-embryonic chicken pepsinogen antiserum (anti-ECPg) as well as to an anti-adult chicken pepsinogen antiserum (anti-ACPg). 2. Zymograms and immunoblots of stomach extracts revealed that anti-ECPg- and anti-ACPg-reactive substances possess peptic activity. 3. The possible relationship between anti-ECPg-reactive pepsinogens in fish and prochymosins in higher vertebrates is discussed.  相似文献   
5.
Bacteriophages (or phages) play major roles in the evolution of bacterial pathogens via horizontal gene transfer. Multiple phages are often integrated in a host chromosome as prophages, not only carrying various novel virulence-related genetic determinants into host bacteria but also providing various possibilities for prophage-prophage interactions in bacterial cells. In particular, Escherichia coli strains such as Shiga toxin (Stx)-producing E. coli (STEC) and enteropathogenic E. coli (EPEC) strains have acquired more than 10 prophages (up to 21 prophages), many of which encode type III secretion system (T3SS) effector gene clusters. In these strains, some prophages are present at a single locus in tandem, which is usually interpreted as the integration of phages that use the same attachment (att) sequence. Here, we present phages integrating into T3SS effector gene cluster-associated loci in prophages, which are widely distributed in STEC and EPEC. Some of the phages integrated into prophages are Stx-encoding phages (Stx phages) and have induced the duplication of Stx phages in a single cell. The identified attB sequences in prophage genomes are apparently derived from host chromosomes. In addition, two or three different attB sequences are present in some prophages, which results in the generation of prophage clusters in various complex configurations. These phages integrating into prophages represent a medically and biologically important type of inter-phage interaction that promotes the accumulation of T3SS effector genes in STEC and EPEC, the duplication of Stx phages in STEC, and the conversion of EPEC to STEC and that may be distributed in other types of E. coli strains as well as other prophage-rich bacterial species.  相似文献   
6.
During a large outbreak of erythema infectiosum in 1987 in Toyama prefecture, Japan, a 32-year-old woman acquired a mild rash on her arms and legs at 18 weeks of gestation. At 26 weeks and 4 days of gestation, the fetus died by hydrops fetalis and pregnancy was terminated. Histological studies of the fetus revealed degeneration of erythroblastic cells in the liver and bone marrow. Extensive extramedullary hematopoiesis and hemosiderin deposits were observed in the liver. Antibody response to human parvovirus B19 virus was demonstrated in maternal sera by ELISA. Furthermore, dot hybridization with the molecularly cloned DNA probe revealed the presence of human parvovirus DNA sequence in the fetal liver, spleen, lung, kidney and placenta. This report describes the first case in Japan of hydrops fetalis caused by human parvovirus B19 infection.  相似文献   
7.
Cos 7 cells transfected with human atrial natriuretic polypeptide (hANP) gene with SV40 enhancer and replication origin sequences expressed hANP gene. The expressed RNA was indistinguishable from native hANP mRNA and the transcribed protein seemed to be properly processed to alpha-hANP and beta-hANP. This system provides a useful approach to investigate the processing of hANPs and the structure-function relationship of amino acid sequences of hANPs.  相似文献   
8.
The DA rat has been proposed as an animal model for the human debrisoquine 4-hydroxylase/bufuralol 1'-hydroxylase genetic deficiency. To determine the mechanism of this deficiency, we isolated and sequenced five cDNAs in the CYP2D gene subfamily including a new IID1 allele and two cDNAs of novel P450s, designated IID3 and IID5. IID3 and IID5 cDNA-deduced amino acid sequences contained 500 and 504 residues with calculated molecular weights of 56,683 and 57,081, respectively. IID5 displayed 20 amino acid differences with the IID1, yet bore only 72% and 76% similarity to IID2 and IID3. Despite an overall nucleotide similarity of 80-98% between the 4 cDNAs, a region of 134 nucleotides of sequence exists that contains only 1 base difference. This region is probably the result of gene conversion events between the P450 IID genes. Although all IID cDNAs were expressed into immunodetectable proteins using the COS cell SV40-based expression system, only IID1 could effectively catalyze the oxidation of the prototype substrate bufuralol. Expression of a cDNA isolated in an earlier study [Gonzalez, F. J., Matsunaga, T., Nagata, K., Meyer, U. A., Nebert, D. W., Pastewka, J., Kozak, C. A., Gillette, J., Gelboin, H. V., & Hardwick, J. P. (1987) DNA 6, 149-161], previously called db1 and now designated IID1v, produced a protein with a drastically reduced activity as compared to cDNA-expressed IID1 despite only four amino acid differences between the two cDNA-deduced protein sequences.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
9.
Induction of microsomal 1-acyl-glycerophosphocholine (GPC) acyltransferase in rat tissues by four peroxisome proliferators, clofibric acid, tiadenol, DEHP and PFOA, was examined. Among the nine tissues examined, kidney, liver and intestinal mucosa responded to the challenges by the peroxisome proliferators to induce the enzyme. The treatment of rats with various dose of clofibric acid, tiadenol, DEHP or PFOA resulted in an induction of kidney microsomal 1-acyl-GPC acyltransferase in a dose-dependent manner. Despite the structural dissimilarity of peroxisome proliferators, the induction of microsomal 1-acyl-GPC acyltransferase was highly correlated with the induction of peroxisomal beta-oxidation. The activity of microsomal 1-acyl-GPC acyltransferase was not affected by changes in hormonal (adrenalectomy, diabetes, hyperthyroidism and hypothyroidism) and nutritional (starvation, starvation-refeeding, fat-free-diet feeding and high-fat-diet feeding) states. The induction of renal microsomal 1-acyl-GPC acyltransferase was seen in mice subsequent to the administration of clofibric acid and tiadenol and in guinea pigs subsequent to the administration of tiadenol. These results may indicate that kidney microsomal 1-acyl-GPC acyltransferase is a highly specific parameter responsive to the challenges by peroxisome proliferators and may suggest that the possibility that the inductions by peroxisome proliferators of microsomal 1-acyl-GPC acyltransferase and peroxisomal beta-oxidation in kidney are co-regulated.  相似文献   
10.
The effect of dietary dehydroisoandrosterone (DHA) on several immunological abnormalities associated with the development of systemic lupus erythematosus in New Zealand Black/New Zealand White F1 (NZB/W) female mice was examined. Despite the extraordinary benefits in prolonged survival and decreased synthesis of antibodies to double-stranded DNA obtained by adding DHA (0.4% w/v) to the diet fed to these mice (Lucas et al. (1985) J. Clin. Invest. 75, 2091-2093), remarkably small changes in the chemistry and function of the immune system were detected. DHA prevented the increases in spleen mass and in peritoneal cell number which occur with age in NZB/W female mice, but did not prevent the development of hypergammaglobulinemia. DHA did not affect peritoneal macrophage functions as measured by the phagocytosis of opsonized and non-opsonized sheep erythrocytes, or the zymosan-stimulated release of PGE2, 6-ketoPGF1 alpha, TXB2 and LTC4. In spleen, DHA delayed the loss of T-cell mitogenic responses until 5.5 months of age, but did not alter the spleen lymphocyte population.  相似文献   
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