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41.
摘要 目的:探究血清淀粉样蛋白A(SAA)、几丁质酶样蛋白YKL-40和肺表面活性物质相关蛋白-A(SP-A)表达水平对的联合检测对小儿难治性肺炎支原体肺炎(RMPP)的预测价值。方法:纳入2019年11月至2021年12月期间我院收治的60例MPP患儿作为研究对象,依据病情最终转归将其分为RMPP组和普通肺炎支原体肺炎(GMPP)组,另纳入同期于我院行体格检查的60例健康儿童作为对照组。收集所有受试儿童的临床资料、实验室指标及影像学结果,采用酶联免疫吸附法(ELISA)检测血清SAA、YKL-40和SP-A的表达水平,应用受试者工作特征曲线(ROC)判定各指标单项检测和联合检测的预测效能。结果:MPP组患儿和对照组儿童一般资料相比无统计学差异(P>0.05)。依据病情最终转归,60例MPP患儿中共有23例(38.33 %)进展为RMPP,RMPP组与GMPP组患儿在白介素-6(IL-6)、C-反应蛋白(CRP)、降钙素原(PCT)、D-二聚体(D-D)等实验室指标以及肺不张、胸腔积液等影像学特征方面相比有统计学差异(P<0.05)。RMPP组和GMPP组血清SAA、YKL-40和SP-A的表达水平显著高于对照组(P<0.05),同时RMPP组血清SAA、YKL-40和SP-A的表达水平显著高于GMPP组(P<0.05)。血清SAA的最佳截断值为39.75 mg/L,预测RMPP发生的ROC曲线下面积为0.894(95%CI:0.861-0.925),敏感度为78.26 %,特异度为86.67 %;血清YKL-40的最佳截断值为31.85 ng/mL,预测RMPP发生的ROC曲线下面积为0.754(95%CI:0.634-0.873),敏感度为73.91 %,特异度为67.21 %;血清SP-A的最佳截断值为35.59 ng/mL,预测RMPP发生的ROC曲线下面积为0.761(95%CI:0.640-0.891),敏感度为73.91 %,特异度为75.00 %;SAA+YKL-40-1+SP-A三者联合检测预测RMPP的AUC为0.914(95%CI:0.871-0.957),敏感度为91.30 %,特异度为91.66 %。结论:血清SAA、YKL-40和SP-A表达水平的检测可作为预测RMPP发生的重要生物学指标,且三者联合检测的预测效能较高,可为临床尽早诊断RMPP、尽早干预、改善患儿预后提供一定的帮助。 相似文献
42.
摘要 目的:探讨血清肿瘤标志物与宫颈癌病理特征的关系及对术后复发的预测研究。方法:选择2015年1月至2017年12月来我院诊治的宫颈癌患者82例作为观察组,选择同期来我院体检的健康女性者50例,两组均使用电化学发光免疫分析法检测血清中的CA125、CA153、CA199、CEA水平,观察组患者随访时间截至2022年12月。对比两组血清CA125、CA153、CA199、CEA水平,分析观察组患者血清CA125、CA153、CA199、CEA水平与临床病理特征的关系,分析观察组患者术后随访复发情况,宫颈癌根治术后患者复发的单因素与多因素Cox回归结果,血清CA125、CA153、CA199、CEA水平对宫颈癌根治术后复发的预测价值。结果:观察组的血清CA125、CA153、CA199、CEA水平明显较对照组高(P<0.05)。宫颈癌患者不同FIGO分期、间质浸润深度及是否存在淋巴结转移间血清CA125、CA153、CA199、CEA水平对比有统计学意义(P<0.05)。82例患者随访时间为13~60个月,中位生存时间为39个月,截止2022年12月末次随访,82例患者术后复发18例(21.95%)。单因素及多因素Cox回归分析表明,FIGO分期在ⅡA期、间质浸润深度≥1/2、有淋巴结转移、CA125≥307.41 U/mL、CA153≥185.89 U/mL、CA199≥153.23 U/mL、CEA≥30.15 ng/mL是影响宫颈癌术后复发的独立危险因素。ROC曲线显示,CA125+CA153+CA199+CEA预测宫颈癌术后复发的AUC明显较CA125、CA153、CA199、CEA单独指标预测价值高(P<0.05)。结论:宫颈癌患者血清CA125、CA153、CA199、CEA高表达,其与间质浸润深度、FIGO 分期、淋巴结转移、术后复发有关,四者联合可作为宫颈癌术后复发的预测指标。 相似文献
43.
Acetyl esterase production was detected in a wood-rotting fungus,Coriolus versicolor, by the formation of a clear zone on a double layer agar plate containing glucose β-d-pentaacetate. Two polysaccharide acetates, carboxymethyl cellulose acetate and xylan acetate, also served as detectable substrates
in place of glucose acetate to form clear zone. In an esterase assay, this fungal esterase showed a higher specificity to
acetylxylan than did porcine liver esterase, indicating that it is an acetylxylan esterase. 相似文献
44.
BCL-2-Related Protein Expression in Apoptosis: Oxidative Stress Versus Serum Deprivation in PC12 Cells 总被引:5,自引:0,他引:5
Abstract: Expression of the BCL-2 protein family members, BAX, BAK, BAD, BCL-xL, BCL-xS, and BCL-2, was measured (by western blotting using specific antibodies) in PC12 cells before and during apoptosis induced by either H2 O2 treatment or by serum deprivation and during rescue from apoptosis by nerve growth factor (NGF). H2 O2 -induced apoptosis, as measured by DNA fragmentation, caused: (a) a dose-dependent increase in BAX, (b) a dose-independent increase in BAK, and (c) a dose-dependent inhibition of BAD expression. By comparison, apoptosis induced by serum deprivation resulted in a time-dependent decrease in both BAX and BAK, along with a dramatic and sudden decrease in BAD expression. However, when PC12 cells were incubated in an apoptosis-sparing medium (i.e., NGF-supplemented serum-free medium), both BAX and BAK were increased significantly, whereas BAD expression remained inhibited. BCL-xL expression was increased by H2 O2 but unaffected by serum deprivation or long-term NGF treatment. Neither BCL-2 nor BCL-xS expression could be detected in PC12 cells under the experimental conditions tested. Our results show that the expression of BAX, BAK, BAD, and BCL-xL is altered in a stimulus-dependent manner but cannot be used to define whether a cell will undergo or survive apoptosis. The similarity between changes in expression of BCL-2-related proteins induced by H2 O2 exposure and NGF rescue could reflect activation in part of a common antioxidant pathway. 相似文献
45.
In this paper we describe a fast and mild method based on the use of a unique cation exchanger and buffers containing ethylene glycol and salt for the purification of the myelin basic protein (MBP; MW 18.5 kDa). MBP thus purified hydrolyses catalytically p-nitrophenyl acetate. This esterase activity facilitates not only the purification of MBP but also indicates that probably it is in its native state, i.e. there is a good chance that the purified molecules are structurally and chemically identical. This is a prerequisite to obtain crystals appropriate for x-ray diffraction and other studies.Abbreviations used MBP
myelin basic protein
- MW
molecular weight
- kDa
kilo Dalton
- octyl-POE
n-octylpolydisperse oligooxyethylene
- CHAPS
3-3-cholamidopropyl dimethylammonio-1-propane-sulfonate
- CTAB
cetyltrimethylammonium bromide
- SDS
sodium dodecyl sulfate
- SDS-PAGE
polyacrylamide gel electrophoresis in the presence of SDS
- G 3707
heptaoxyethylene lauryl ether
- TWEEN-20
polyoxyethylenesorbitan-monolaurat
- EDTA
ethylenediaminetetraacetic acid
- HEPES
N-(2-hydroxyethyl)-piperazine-N-(2-ethanesulfonic acid) 相似文献
46.
47.
R Manjunath S I Chung A B Mukherjee 《Biochemical and biophysical research communications》1984,121(1):400-407
Uteroglobin, a progesterone induced, pregnancy related protein, can be incorporated into higher molecular weight proteins by human placental Factor XIIIa. This process is time dependent, requires CaCl2 and can be inhibited by the addition of polylysine, dansylcadavarine or histamine. Crosslinking of uteroglobin into higher molecular weight proteins can also be brought about by guinea pig liver transglutaminase. Such a process may be involved in the modification of epididymal spermatozoa to suppress their antigenicity. 相似文献
48.
Ass. Prof. Dr. A. Römmler W. Seinsch A. S. Hasan F. Haase 《Cell and tissue research》1978,190(1):135-149
The effects of single and repeated LH-RH injections at 120 min intervals on female rat LH gonadotrophs and on pituitary and serum LH levels were investigated using electronmicroscopy and radioimmunoassay. A temporary stimulation of granule release, of protein and new granule synthesis and of the accumulation of lysosomal structures was found in LH cells after the first LH-RH injection. The temporary stimulations were massively enhanced after the second injection. These consecutive yet in their time-sequence overlapping processes account for the initial depletion of secretory granule content (3--15 min after LH-RH injection), for the subsequent regranulation and accumulation of granules above control levels (60--120 min after injection) and also for the reduction in the number of granules to control levels (150 min after LH-RH injection and thereafter). Increased polymorphic lysosomal structures are believed to be responsible for this reduction of excess granules. The amount of assayable pituitary and serum LH generally corresponds with the morphological changes observed in LH-gonadotrophs, thus further substantiating the above observations. A schema which summarizes the observed morphological and hormonal changes in their time-sequence in response to LH-RH stimulation depicts the short-term regulation of secretory processes in female gonadotrophs. 相似文献
49.
SYNOPSIS Enhanced esterase C activity could be demonstrated by starch gel electrophoresis in various stocks of Paramecium spp. (P. primaurelia stocks 90 and 540, P. biaurelia stock 93, P. tetraurelia stock 29. P. pentaurelia stock 87, P. octaurelia stocks 31 and 300, and P. multimicronucleatum species 3, stock 8 MO) grown in Adaptation Medium. This esterase, however, was barely detectable when they were cultivated in Axenic Medium. Addition of trypticase to Adaptation Medium resulted in reduction of esterase C in the ciliates. This effect is ascribable to Na acetate present in trypticase. Since esterase C increased with the decrease in acetate concentration (as estimated by gas-liquid chromatography) during growth of Paramecium, acetate appears to be utilized by the cells. Sensitivity of esterase C to acetate occurs in all 6 species of Paramecium examined. Different stocks within a species may have different levels of sensitivity; in one case this is genetically determined. The results emphasize the importance of controlling and manipulating growth conditions for the assessment of inter- and intraspecies variations in the isozymes of Paramecium. 相似文献
50.
James E. Womack Muriel T. Davisson Eva M. Eicher Debra A. Kendall 《Biochemical genetics》1977,15(3-4):347-355
A method for detecting two alleles at Np-1 (nucleoside phosphorylase) and three alleles at Es-10 (esterase 10) from mouse blood by cellulose acetate electrophoresis is described. The allelic constitution at these loci for 44 inbred strains and stocks was determined. The location of Np-1 on chromosome 14 was established by backcross experiments in which alleles at Np-1 and Robertsonian translocations were segregating. Es-10 was shown to be linked to Np-1, and the following genetic map of Chr 14 was constructed: centromere-(8.9±4.0 cM)-[Np-1, Wc]-(10.2±1.9 cM)-Es-10-(15.5±3.7 cM)-s. The homologous human loci, NP and ES-D, are not linked.This work was supported by Contract E(11-1)-3267 with the Energy Research and Development Administration, by Contracts NO1-ES4-2156 and NO1-ES4-2159 with the National Institute of Environmental Health Sciences, and by Grants GM 19656 and GM 20919 from the National Institute of General Medical Sciences. D. A. K. was a participant in the 1975 Summer Program for College, Graduate, and Medical Students, which was supported, in part, by the Clark Foundation. The Jackson Laboratory is fully accredited by the American Association for Accreditation of Laboratory Animal Care. 相似文献