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123.
Danni Zheng Shoichiro Sato Yong-Jun Cao Hisatomi Arima Cheryl Carcel John Chalmers 《Chronobiology international》2016,33(9):1182-1187
Previous studies consistently reported a diurnal variation in the occurrence of intracerebral hemorrhage (ICH), with a morning peak. However, limited knowledge exists on the circadian pattern of ICH severity and outcome. This study aimed to determine possible associations between ICH onset time and admission severity and 90-day outcomes using the combined data set of the pilot and main-phase Intensive blood pressure (BP) reduction in an acute cerebral hemorrhage trial (INTERACT). The ICH onset time was categorized into three groups (1: 00:00–07:59; 2: 08:00–15:59; and 3: 16:00–23:59). We found an association between onset time and low Glasgow Coma Scale score: aOR (time 1: 1.72, 95% CI 1.12–2.66; time 3: 1.95, 95% CI 1.31–2.89, p = 0.003; in comparison to time 2). There was no association between onset time and volume of ICH (adjusted p = 0.354) or 90-day outcomes of death or major disability, and death and major disability separately (all adjusted p > 0.4). The results showed that more severe cases of ICH patients, defined by a reduced level of consciousness, had late afternoon to early morning stroke onset, but this was unrelated to baseline hematoma volume or location. There was no circadian influence on ICH clinical outcome. 相似文献
124.
Soo Kyung Nam Sumi Yun Jiwon Koh Yoonjin Kwak An Na Seo Kyoung Un Park Duck-Woo Kim Sung-Bum Kang Woo Ho Kim Hye Seung Lee 《PloS one》2016,11(3)
Background
Anti-EGFR antibody–based treatment is an important therapeutic strategy for advanced colorectal cancer (CRC); despite this, several mutations—including KRAS, BRAF, and PIK3CA mutations, and HER2 amplification—are associated with the mechanisms underlying the development of resistance to anti-EGFR therapy. The aim of our study was to investigate the frequencies and clinical implications of these genetic alterations in advanced CRC.Methods
KRAS, BRAF, and PIK3CA mutations were determined by Cobas real-time polymerase chain reaction (PCR) in 191 advanced CRC patients with distant metastasis. Microsatellite instability (MSI) status was determined by a fragmentation assay and HER2 amplification was assessed by silver in situ hybridization. In addition, KRAS mutations were investigated by the Sanger sequencing method in 97 of 191 CRC cases.Results
Mutations in KRAS, BRAF, and PIK3CA were found in 104 (54.5%), 6 (3.1%), and 25 (13.1%) cases of advanced CRC, respectively. MSI-high status and HER2 amplification were observed in 3 (1.6%) and 16 (8.4%) cases, respectively. PIK3CA mutations were more frequently found in KRAS mutant type (18.3%) than KRAS wild type (6.9%) (P = 0.020). In contrast, HER2 amplifications and BRAF mutations were associated with KRAS wild type with borderline significance (P = 0.052 and 0.094, respectively). In combined analyses with KRAS, BRAF and HER2 status, BRAF mutations or HER2 amplifications were associated with the worst prognosis in the wild type KRAS group (P = 0.004). When comparing the efficacy of detection methods, the results of real time PCR analysis revealed 56 of 97 (57.7%) CRC cases with KRAS mutations, whereas Sanger sequencing revealed 49 cases (50.5%).Conclusions
KRAS mutations were found in 54.5% of advanced CRC patients. Our results support that subgrouping using PIK3CA and BRAF mutation or HER2 amplification status, in addition to KRAS mutation status, is helpful for managing advanced CRC patients. 相似文献125.
A functionally active heavy chain derived from human high molecular weight urokinase 总被引:2,自引:0,他引:2
Human high molecular weight urokinase, a plasminogen activator, when minimally reduced with 0.01 M 2-mercaptoethanol for 10 h at pH 8.0 and 25 degrees C and then carboxymethylated with sodium iodoacetate, gave two chains, a functionally active heavy chain with about 80% of the original activity and a light chain. These two chains were found to be linked by a single interchain disulfide bond. The functionally active heavy chain can be isolated by an affinity chromatography method with [N alpha-(epsilon-aminocaproyl)-DL-homoarginine hexylester]-Sepharose. The light chain, which has no enzyme activity, is not adsorbed to the affinity matrix, whereas the active heavy chain was adsorbed and subsequently eluted. The active heavy chain was further purified by gel filtration on Sephadex G-100. This preparation was found to be homogeneous by both analytical and sodium dodecyl sulfate-polyacrylamide disc gel electrophoresis. The molecular weight of the active heavy chain was determined to be 33,000 by Sephadex G-100 gel filtration and 31,000 by sodium dodecyl sulfate-polyacrylamide disc gel electrophoresis. Its specific activity, with L-pyroglutamyl-glycyl-L-arginine-p-nitroanilide, was determined to be 208,000 IU/mg of protein. Approximately 87% active sites were found by p-nitrophenyl-p'-guanidino-benzoate titration with a molar activity of 7.41 X 10(9) IU/mmol of active site. The active heavy chain when compared to low molecular weight urokinase has a similar molecular weight, specific activity, and amino acid composition. The NH2-terminal residue found in the active heavy chain was lysine which was the same as that found in low molecular weight urokinase, whereas the NH2-terminal residues found in high molecular weight urokinase were serine and lysine. Serine is the NH2-terminal residue of the light chain of high molecular weight urokinase. The steady state kinetic parameters of activation of human Glu-plasminogen by the active heavy chain were also similar to low molecular weight urokinase, as were the amidase parameters of these enzymes. The Michaelis constants of activation (Kplg) were 2.11 and 2.21 microM, respectively; the catalytic rate constants of activation (kplg) were 51.7 and 44.1 min-1, respectively, with second order rate constants, kplg/Kplg of 24.5 and 20.2 microM-1 min-1, respectively. 相似文献
126.
Genetic Mapping of a Group of Temperature-Sensitive dna Initiation Mutants in BACILLUS SUBTILIS 总被引:6,自引:0,他引:6 下载免费PDF全文
Recombination frequencies among temperature-sensitive dna mutants from various laboratories were analyzed, and eleven dna mutants were found to be closely linked. They are classified as group B dna mutants, since these are closely linked with dnaB19, originally isolated and approximately mapped near leuA8 by KARAMATA and GROSS (1970). However, the dnaB19 mutation itself has relatively high recombination frequencies with the other mutations, thus, we propose to subdivide the dnaB group into two subgroups--dnaBI, including ten mutants (dna-1, dna-3, dna-5, dna-17, dna-27, dna-51, dna-60, dna-62, dna-103 and dna-134) and dnaBII, including dnaB19. The map order of dnaB and markers in the vicinity was determined to be argA-citH-citC-phoP-PhoR-polA-dnaBI-dnaBII-citF-leuA-pheA. 相似文献
127.
Summary An in vitro complementation was observed between the gene 36 product and the genes 37–38 directed component of the tail fiber of bacteriophage T4. A possible role of the gene 36 product as well as the reconstitution process in the complementation were briefly discussed.Biozentrum, University of Basel, CH-4056 Basel, Swiss. 1 The following defectives in T4 fiber genes were used: single defective mutants; amE1 (gene 36–), amN52 (gene 37–) and amB262 (gene 38–); double defective mutants; amN52:B262 (genes 37–38–), amA455: N52 (genes 34–37–) and amB252:N52 (genes 35–37–); and triple defective mutants; am A455:B252:N52 (genes 34–35–37–) and amA455:B252:B262 (genes 34–35–38–). 相似文献
128.
Luo Yao-Hua; Steinberg Leonel; Suda Shoichiro; Kumazawa Shuzo; Mitsui Akira 《Plant & cell physiology》1991,32(6):897-900
Cyanobacteria, having primary photosynthetic reactions similarto higher plants, are capable of producing large quantitiesof molecular hydrogen by nitrogenase and/or hydrogenase deliveringelectrons to hydrogen ions via ferredoxin or oxidation of NADPH.We measured the deuterium/hydrogen (D/H) ratios of the hydrogengas photoproduced by Synechococcus sp. Miami BG 043511 and Anabaenasp. TU 37-1, and demonstrate that D values of their hydrogengas are extremely low (about 600%) when compared withthat of available water (7%).This depletion gives a meanfractionation factor (a) of 0.43, which is similar to that calculatedfor hydrogen ions at equilibrium with water (0.35) and hydrogenproduced by electrolysis of water (0.24) but significantly differentfrom those of carbon bound hydrogens (>0.83). Thus hydrogenions available for protonation of NADP+ may be extremely deuteriumdepleted. Our results may explain why D/H ratios of nitratedcellulose or lipids from most plants are always depleted relativeto water available for photosynthesis.
3 On leave from School of Marine Science and Technology, TokaiUniversity, 3-20-1 Orido, Shimizu, 424 Japan (Received April 1, 1991; Accepted June 21, 1991) 相似文献
129.
Assignment of the human protein C gene (PROC) to chromosome region 2q14----q21 by in situ hybridization 总被引:3,自引:0,他引:3
The protein C gene (PROC) was mapped by in situ hybridization. A genomic DNA probe containing the first three exons was 3H-labeled by nick translation, and this was then hybridized in situ to human chromosome preparations. The results localize the gene to 2q14----q21. 相似文献
130.
Y Nishimune Y Nishina T Sumi M Kosaka M Takeda K Matsumoto A Matsushiro M Sakuda 《Biochemical and biophysical research communications》1989,165(1):65-72
Embryonal carcinoma(EC) cells, the undifferentiated stem cells of teratocarcinomas, have many properties in common with pluripotent embryonic cells, and thus provide an excellent system for studying the early events involved in embryonic development and stem cell differentiation. We have isolated three novel mutants with temperature-sensitive(ts) cell growth that were able to differentiate at a non-permissive temperature for cell growth. These mutations affect the progression of the cell cycle, leading to the transient accumulation of cells in a specific phase, the S phase, of the cell cycle, which is likely to be the primary cause of stem cell differentiation of EC cells at non-permissive temperature. Isolation of these mutants strongly supports the notion that there is a close association between the inhibition of DNA synthesis and EC cell differentiation. 相似文献