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141.
A total of 2035 Mycosphaerella graminicola strains collected from 16 geographic locations on four continents were assayed for the mating type locus. RFLP fingerprints were used to identify clones in each population. At the smallest spatial scale analyzed, both mating types were found among fungal strains sampled from different lesions of the same leaf as well as from different pycnidia in the same lesion. At larger spatial scales, the two mating types were found at equal frequencies across spatial scales ranging from several square meters to several thousand square kilometers. Though the absolute frequencies of the two mating types sometimes varied for different sampling units within the same spatial scale in the hierarchy (plots within a field, fields within a country, or different continents of the world), none of the differences were statistically significant from the null hypothesis of equal frequencies for the two mating types. The evolutionary forces likely to maintain the even distribution of the two mating types in this pathogen were discussed. 相似文献
142.
Haemocyte types of the scallop (Chlamys farreri) were identified by Giemsa stain and flow cytometry (FCM). Additionally, the activities of peroxidase (POD), phenoloxidase (PO) and alkaline phosphatase (ALP) in haemocytes were analysed by immunocytochemical and biochemical methods. The results indicate that there were two types of haemocytes in the scallop, hyalinocytes and granulocytes, and that POD, PO and ALP were more abundant and more active in granulocytes than in hyalinocytes. 相似文献
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Background
The early detection of ovarian cancer has the potential to dramatically reduce mortality. Recently, the use of mass spectrometry to develop profiles of patient serum proteins, combined with advanced data mining algorithms has been reported as a promising method to achieve this goal. In this report, we analyze the Ovarian Dataset 8-7-02 downloaded from the Clinical Proteomics Program Databank website, using nonparametric statistics and stepwise discriminant analysis to develop rules to diagnose patients, as well as to understand general patterns in the data that may guide future research.Results
The mass spectrometry serum profiles derived from cancer and controls exhibited numerous statistical differences. For example, use of the Wilcoxon test in comparing the intensity at each of the 15,154 mass to charge (M/Z) values between the cancer and controls, resulted in the detection of 3,591 M/Z values whose intensities differed by a p-value of 10-6 or less. The region containing the M/Z values of greatest statistical difference between cancer and controls occurred at M/Z values less than 500. For example the M/Z values of 2.7921478 and 245.53704 could be used to significantly separate the cancer from control groups. Three other sets of M/Z values were developed using a training set that could distinguish between cancer and control subjects in a test set with 100% sensitivity and specificity.Conclusion
The ability to discriminate between cancer and control subjects based on the M/Z values of 2.7921478 and 245.53704 reveals the existence of a significant non-biologic experimental bias between these two groups. This bias may invalidate attempts to use this dataset to find patterns of reproducible diagnostic value. To minimize false discovery, results using mass spectrometry and data mining algorithms should be carefully reviewed and benchmarked with routine statistical methods.146.
Sakurai T Zhan L Fujita T Kataoka K Shimizu A Samejima T Yamaguchi S 《Bioscience, biotechnology, and biochemistry》2003,67(5):1157-1159
Myrothecium verrucaria bilirubin oxidase expressed in Aspergillus oryzae is in a resting form different from that of the authentic bilirubin oxidase, but reaches the resting form of the authentic enzyme after one cycle of reduction and reoxidation with dioxygen as shown by the absorption and electron paramagnetic resonance spectra. 相似文献
147.
A pilot plant study using a vertically moving biofilm process to treat municipal wastewater 总被引:5,自引:0,他引:5
The pilot plant study comprised the construction and monitoring of a new vertically moving biofilm system (VMBS) for treating municipal wastewater. The system operated on site for 11 months. The biofilm module in this system, consisting of high surface area plastic media, was vertically and repeatedly moved in cycles up into the air and down into the wastewater. The vertical movement of the biofilm module supplied sufficient oxygen for the removal of the organic carbon in the wastewater. The overall physical oxygen transfer coefficient (Kla) measured at the cycle speed of six cycles per minute was 2.53 per hour. During the pilot study, dissolved oxygen (DO) concentrations in the bulk fluid were in the range of 1.5-5 mg/l. It was found that the areal removal rate of filtered chemical oxygen demand (COD) was up to 35 g COD/(m(2)day) and the bulk fluid volumetric filtered COD removal rate was 2.62 kg COD/(m(3)day). The field experiment showed that clogging commonly found in other biofilm systems did not occur in this system. The power consumption was in the range of 0.09-0.25 k Wh/m(3) wastewater flow, 0.40-2.19 k Wh/kg COD removal and 1.24-1.74 k Wh/kg BOD removal. The new biofilm system offers potential for reduced reactor volumes, energy saving, simple construction and easy operation. 相似文献
148.
一氧化氮抑制血管紧张素Ⅱ和内皮素—1诱导的心肌细胞原癌基因c—fo … 总被引:3,自引:0,他引:3
在原代培养的新生大鼠心肌细胞上,探讨一氧化氮(NO)对血管紧张素Ⅱ(AⅡ)和内皮素-1(ET-1)诱导的心肌细胞肥大和原癌基因c-fos表达的影响。用Bradford法测定心肌细胞总蛋白含量(作为心肌细胞肥大的指标);用基因特异性引物和SuperScript一步法进行逆转录聚合酶链式反应(RT-PCR),检测大鼠心肌细胞原癌基因c-fos的表达(以GAPDH为内标)。结果显示,AⅡ和ET-1分别作 相似文献
149.
中国株丙型肝炎病毒(HCV)结构区蛋白在昆虫细胞中的表达及加工 总被引:4,自引:1,他引:3
利用杆状病毒表达系统在昆虫细胞中表达了完整的中国河北株丙丙型肝炎病毒结构蛋白。免疫印迹实验结果显示,表达产物中有一系列分子量不同、可以与HCV抗体阳性病人血清反应的蛋白,表明结构蛋白被宿主细胞蛋白酶切割与加工,相应分别为20kD的核心蛋白、32kD糖基化的E1蛋白40kD的未糖化的E2蛋白和70kD糖基化的E2蛋白,另有80kD及100kD的两组前体蛋白。利用表达产物检测慢性HCV感染者血清,发现 相似文献
150.
Swallow John G.; Garland Jr. Theodore; Carter Patrick A.; Zhan Wen-Zhi; Sieck Gary C. 《Journal of applied physiology》1998,84(1):69-76
Swallow, John G., Theodore Garland, Jr., Patrick A. Carter,Wen-Zhi Zhan, and Gary C. Sieck. Effects of voluntary activity andgenetic selection on aerobic capacity in house mice(Mus domesticus). J. Appl. Physiol. 84(1): 69-76, 1998.An animal model was developed to study effects on components ofexercise physiology of both "nature" (10 generations of geneticselection for high voluntary activity on running wheels) and"nurture" (7-8 wk of access or no access to running wheels,beginning at weaning). At the end of the experiment, mice from bothwheel-access groups were significantly lighter in body mass than micefrom sedentary groups. Within the wheel-access group, a statisticallysignificant, negative relationship existed between activity and finalbody mass. In measurements of maximum oxygen consumption during forcedtreadmill exercise (O2 max), mice withwheel access were significantly more cooperative than sedentary mice;however, trial quality was not a significant predictor of individualvariation in O2 max.Nested two-way analysis of covariance demonstrated that both geneticselection history and access to wheels had significant positive effects on O2 max.A 12% difference inO2 max existedbetween wheel-access selected mice, which had the highestmass-correctedO2 max, andsedentary control mice, which had the lowest. The respiratory exchangeratio at O2 max wasalso significantly lower in the wheel-access group. Our results suggestthe existence of a possible genetic correlation between voluntaryactivity levels (behavior) and aerobic capacity (physiology). 相似文献