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151.
Mutations in copper-zinc superoxide dismutase (SOD1) have been linked to a subset of familial amytrophic lateral sclerosis (fALS), a fatal neurodegenerative disease characterized by progressive motor neuron death. An increasing amount of evidence supports that mitochondrial dysfunction and apoptosis activation play a critical role in the fALS etiology, but little is known about the mechanisms by which SOD1 mutants cause the mitochondrial dysfunction and apoptosis. In this study, we use proteomic approaches to identify the mitochondrial proteins that are altered in the presence of a fALS-causing mutant G93A-SOD1. A comprehensive characterization of mitochondrial proteins from NSC34 cells, a motor neuron-like cell line, was achieved by two independent proteomic approaches. Four hundred seventy unique proteins were identified in the mitochondrial fraction collectively, 75 of which are newly discovered proteins that previously had only been reported at the cDNA level. Two-dimensional gel electrophoresis was subsequently used to analyze the differences between the mitochondrial proteomes of NSC34 cells expressing wild-type and G93A-SOD1. Nine and 36 protein spots displayed elevated and suppressed abundance respectively in G93A-SOD1-expressing cells. The 45 spots were identified by MS, and they include proteins involved in mitochondrial membrane transport, apoptosis, the respiratory chain, and molecular chaperones. In particular, alterations in the post-translational modifications of voltage-dependent anion channel 2 (VDAC2) were found, and its relevance to regulating mitochondrial membrane permeability and activation of apoptotic pathways is discussed. The potential role of other proteins in the mutant SOD1-mediated fALS is also discussed. This study has produced a short list of mitochondrial proteins that may hold the key to the mechanisms by which SOD1 mutants cause mitochondrial dysfunction and neuronal death. It has laid the foundation for further detailed functional studies to elucidate the role of particular mitochondrial proteins, such as VDAC2, in the pathogenesis of familial ALS.  相似文献   
152.
A self-designed novel solid-state fermentation (SSF) bioreactor named “gas double-dynamic solid-state fermentation bioreactor (GDSFB)” showed great success in processes for the production of several valuable products. For the present study, a simple GDSFB (2 L in volume) was designed to investigate the impact of exhaust time on SSF performance. Both air pressure and vent aperture significantly influenced the exhaust time. The production of cellulase by Penicillium decumbens JUA10 was studied in this bioreactor. When the vent aperture was maintained at 0.2 cm, the highest FPA activity of 17.2 IU/g dry solid-state medium was obtained at an air pressure of 0.2 MPa (gauge pressure). When the air pressure was maintained at 0.2 MPa, a vent aperture of 0.3 cm gave the highest FPA activity of 18.0 IU/g dry solid-state medium. Further analysis revealed that the exhaust time was a crucial indicator of good performance in GDSFB.  相似文献   
153.
The MRC1 gene, encoding the human mannose receptor (MR), is a member of the C-type lectin receptors family. MR can recognize and bind to Mycobacterium tuberculosis by the extracellular structure, and play a role in antigen-presenting and maintaining a stable internal environment. This study aimed to investigate potential associations of SNPs in exon 7 of the MRC1 gene with pulmonary tuberculosis (TB). G1186A, G1195A, T1212C, C1221G, C1303T and C1323T were genotyped using PCR and DNA sequencing in 595 Chinese Uygur and 513 Kazak subjects. In the Uygur, the frequency of allele G (P = 0.031, OR = 1.29, 95 % CI = 1.02–1.62) and AA genotype (P = 0.033, OR = 1.64, 95 % CI = 1.04–2.60) for G1186A was lower in the pulmonary TB than healthy control and were significantly correlated with pulmonary TB. After adjustment for age and gender, G1186A was found to be additive models in association with pulmonary TB (P = 0.04, OR = 1.27, 95 % CI = 1.01–1.60). By calculating linkage disequilibrium, the frequency of haplotype GGTCCT (P = 0.032, OR = 0.75, 95 % CI = 0.57–0.97) and GGTCCC (P = 0.044, OR = 0.57, 95 % CI = 0.33–0.99) was significantly associated with pulmonary TB. No association was found between other SNPs and pulmonary TB. In the Kazak, all SNPs were not associated with pulmonary TB. Our results suggest that genetic factors play an important role in susceptibility to pulmonary TB at the individual level, and provide an experimental basis to clarify the pathogenesis of pulmonary TB.  相似文献   
154.
研究典型籼稻品种‘七山占’和典型粳稻品种‘秋光’杂交衍生的重组自交系群体及其双亲的花时性状,并用该群体的分子连锁图谱进行QTL分析,共检测到6个与水稻花时性状相关的QTL,包括1个始花时QTL、3个盛花时QTL和2个终花时QTL,分别位于第1、2、7、8、10和12染色体,单个QTL的贡献率在7.08%~26.95%之间。有4个增效等位基因来源于粳型亲本‘秋光’,2个来源于籼型亲本‘七山占’。  相似文献   
155.
为了给表达广谱抗真菌蛋白转基因水稻的安全性评估提供基础数据,本文以表达广谱抗真菌蛋白转基因水稻转品1和转品8及非转基因七丝软粘(对照)为试材,对其秸秆化学成分进行分析,同时,采用傅立叶变换红外光谱(FTIR)和X-射线衍射(XRD)方法观察秸秆中不同部位纤维素结构的变化情况。研究结果显示:(1)转基因水稻转品1和转品8与对照在秸秆相同部位的化学成分含量不存在显著差异;(2)转基因水稻转品1和转品8及对照在秸秆相同部位纤维素的红外吸收峰形状基本一致,且品种间的吸收峰强度和结晶指数(O'KI和N·O'KI)也无显著差异;(3)转品1和转品8秸秆的X-射线衍射图与对照相似,且结晶度(CrI)与对照无显著差异。综上所述,广谱抗真菌基因的导入不会对水稻的化学成分、纤维素结构及晶体结构产生明显影响。  相似文献   
156.
选取龙脑含量高的优良单株,以其树干基部的幼嫩萌条为外植体开展龙脑樟组培快繁技术研究。结果表明:以改良MS+BA 2.0 mg·L-1+NAA 0.1 mg·L-1为芽诱导培养基,诱导率为93%;最佳增殖培养基为改良MS+BA 2.0 mg·L-1 +NAA 0.05 mg·L-1,增殖系数为5.57,生长周期为30 d;适宜的增殖培养条件为温度25℃,光照强度3 000 lx,光照时间11 h,不定芽长势良好;最佳生根培养基为1/2改良MS+IBA 0.5 mg·L-1+IAA 0.4 mg·L-1+蔗糖20 g·L-1,生根率可达97.3%,生根条数为3~5条,生根时间为12 d;以草炭+珍珠岩(3∶1)为移栽基质,成活率可达86.2%。通过试验总结出一套组培快繁技术体系,可应用于龙脑樟组培苗工厂化生产。  相似文献   
157.
While there exists a wealth of information about genetic influences on gene expression, less is known about how inherited variation influences the expression and post-translational modifications of proteins, especially those involved in intracellular signaling. The PI3K/AKT/mTOR signaling pathway contains several such proteins that have been implicated in a number of diseases, including a variety of cancers and some psychiatric disorders. To assess whether the activation of this pathway is influenced by genetic factors, we measured phosphorylated and total levels of three key proteins in the pathway (AKT1, p70S6K, 4E-BP1) by ELISA in 122 lymphoblastoid cell lines from 14 families. Interestingly, the phenotypes with the highest proportion of genetic influence were the ratios of phosphorylated to total protein for two of the pathway members: AKT1 and p70S6K. Genomewide linkage analysis suggested several loci of interest for these phenotypes, including a linkage peak for the AKT1 phenotype that contained the AKT1 gene on chromosome 14. Linkage peaks for the phosphorylated:total protein ratios of AKT1 and p70S6K also overlapped on chromosome 3. We selected and genotyped candidate genes from under the linkage peaks, and several statistically significant associations were found. One polymorphism in HSP90AA1 was associated with the ratio of phosphorylated to total AKT1, and polymorphisms in RAF1 and GRM7 were associated with the ratio of phosphorylated to total p70S6K. These findings, representing the first genomewide search for variants influencing human protein phosphorylation, provide useful information about the PI3K/AKT/mTOR pathway and serve as a valuable proof of concept for studies integrating human genomics and proteomics.  相似文献   
158.
目的探讨氧气雾化吸入疗法在老年喘息型支气管肺炎治疗中的价值。方法将90例老年喘息型支气管肺炎患者随机分为2组。对照组采用常规疗法即静脉点滴消炎、抗病毒、解痉平喘、祛痰药物及对症治疗。治疗组在上述常规疗法的基础上辅助应用氧气雾化吸入疗法。结果治疗组排痰效果、临床症状/体征消失时间明显缩短(P〈0.05,P〈0.01)。结论氧气雾化吸入疗法治疗老年喘息型支气管肺炎,改善症状疗效显著,起效快,用药少,操作简单,病人乐于接受,值得在基层医疗机构临床推广使用。  相似文献   
159.
目的探讨十二指肠镜、胆道镜、腹腔镜等多镜联合治疗胆总管结石合并胆囊结石的技术优势。方法采用腹腔镜胆总管探查术+腹腔镜胆囊切除术(LCBDE+LC)和内窥镜逆行胰胆管造影术+内窥镜下括约肌切开取石术+腹腔镜胆囊切除术(ERCP+EST+LC)两种术式治疗胆总管结石合并胆囊结石患者。结果有两组病例,其中LCBDE+LC组36例,本组术后胆道残余结石2例,后经T管窦道行胆道镜取石治愈。ERCP+EST+LC组54例,本组术后并发一过性高淀粉酶血症3例,发生急性轻型胰腺炎2例。结论多镜联合治疗胆总管结石合并胆囊结石具有创伤小、效果好、并发症少、恢复快的优点,多镜联合发挥出其独特技术优势,避免了因接受传统开腹手术而造成较大创伤的不合理治疗模式。  相似文献   
160.
拟诺卡菌属(Nocardiopsis)是拟诺卡菌科(Nocardiopsaceae) 的唯一属.该属内进行物种鉴别时通常是在多相分类方法基础上,以全基 因组杂交同源性在70%以下的为不同物种,此为国际公认的定种标准;但在 进行大量菌株的比对时操作比较复杂,于是多种基于DNA的基因图谱技术发 展起来.本实验利用适宜引物,对拟诺卡菌属15株基准株基因组DNA的16S -23S rDNA 间隔区序列(ITS)和REP序列进行了扩增,获得了两种基因指 纹图谱,同时根据UPGMA聚类法构建了相应的进化距离树图.结果表明,对 于拟诺卡菌属中不同物种的区分,两种基因图谱技术的分辨力相当,均可 以较好的呈现物种间差异,可以作为拟诺卡菌属菌株多相分类的组成部分 ,应用于物种水平的分类与鉴定.  相似文献   
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