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961.
Most studies published to date that used fecal glucocorticoid measurements to assess adrenocortical activity in primate (and many nonprimate) species applied a specific cortisol or corticosterone assay. However, since these native glucocorticoids are virtually absent in the feces of most vertebrates, including primates, the validity of this approach has recently been questioned. Therefore, the overall aim of the present study was to assess the validity of four enzyme-immunoassays (EIAs) using antibodies raised against cortisol, corticosterone, and reduced cortisol metabolites (two group-specific antibodies) for assessing adrenocortical activity using fecal glucocorticoid metabolite (GCM) measurements in selected primate species (marmoset, long-tailed macaque, Barbary macaque, chimpanzee, and gorilla). Using physiological stimulation of the hypothalamo-pituitary-adrenocortical (HPA) axis by administering exogenous ACTH or anesthesia, we demonstrated that at least two assays detected the predicted increase in fecal GCM levels in response to treatment in each species. However, the magnitude of response varied between assays and species, and no one assay was applicable to all species. While the corticosterone assay generally was of only limited suitability for assessing glucocorticoid output, the specific cortisol assay was valuable for those species that (according to high-performance liquid chromatography (HPLC) analysis data) excreted clearly detectable amounts of authentic cortisol into the feces. In contrast, in species in which cortisol was virtually absent in the feces, group-specific assays provided a much stronger signal, and these assays also performed well in the other primate species tested (except the marmoset). Collectively, the data suggest that the reliability of a given fecal glucocorticoid assay in reflecting activity of the HPA axis in primates clearly depends on the species in question. Although to date there is no single assay system that can be used successfully across species, our data suggest that group-specific assays have a high potential for cross-species application. Nevertheless, regardless of which GC antibody is chosen, our study clearly reinforces the necessity of appropriately validating the respective assay system before it is used.  相似文献   
962.
Mucosal pathogens recognize glycoconjugate receptors at the site of infection, and attachment is an essential first step in disease pathogenesis. Inhibition of attachment may prevent disease, and several approaches have been explored. This review discusses the prevention of bacterial attachment and disease by agents that modify the glycosylation of cell surface glycoconjugates. Glycosylation inhibitors were tested in the urinary tract infection model, where P-fimbriated Escherichia coli rely on glycosphingolipid receptors for attachment and tissue attack. N-butyldeoxynojirimycin blocked the expression of glucosylceramide-derived glycosphingolipids and attachment was reduced. Bacterial persistence in the kidneys was impaired and the inflammatory response was abrogated. N-butyldeoxynojirimycin was inactive against strains which failed to engage these receptors, including type 1 fimbriated or nonadhesive strains. In vivo attachment has been successfully prevented by soluble receptor analogues, but there is little clinical experience of such inhibitors. Large-scale synthesis of complex carbohydrates, which could be used as attachment inhibitors, remains a technical challenge. Antibodies to bacterial lectins involved in attachment may be efficient inhibitors, and fimbrial vaccines have been developed. Glycosylation inhibitors have been shown to be safe and efficient in patients with lipid storage disease and might therefore be tested in urinary tract infection. This approach differs from current therapies, including antibiotics, in that it targets the pathogens which recognize these receptors.  相似文献   
963.
黄金周游客干扰对圈养大熊猫应激影响初探   总被引:2,自引:0,他引:2  
通过非损伤性手段,监测了"五一"黄金周期间北京动物园一雌一雄两只圈养大熊猫粪样中的皮质醇水平变化.结果显示,随着客流量的明显上升,雌雄个体粪样中的皮质醇水平均出现了明显的升高.其中雄性大熊猫粪样中皮质醇含量的变化与前一日的客流量存在显著性相关,而雌性个体粪样中的皮质醇水平则与前一日客流量存在极显著的相关性.  相似文献   
964.
Here we describe the first detailed catalog of gene expression in the developing lower urinary tract (LUT), including epithelial and mesenchymal portions of the developing bladder, urogenital sinus, urethra, and genital tubercle (GT) at E13 and E14. Top compartment-specific genes implicated by the microarray data were validated using whole-mount in situ hybridization (ISH) over the entire LUT. To demonstrate the potential of this resource to implicate developmentally critical features, we focused on gene expression patterns and pathways in the sexually indeterminate, androgen-independent GT. GT expression patterns reinforced the proposed similarities between development of GT, limb, and craniofacial prominences. Comparison of spatial expression patterns predicted a network of Wnt7a-associated GT-enriched epithelial genes, including Gjb2, Dsc3, Krt5, and Sostdc1. Known from other contexts, these genes are associated with normal epidermal differentiation, with disruptions in Dsc3 and Gjb2 showing palmo-plantar keratoderma in the limb. We propose that this gene network contributes to normal foreskin, scrotum, and labial development. As several of these genes are known to be regulated by, or contain cis elements responsive to retinoic acid, estrogen, or androgen, this implicates this pathway in the later androgen-dependent development of the GT.  相似文献   
965.
黄鳝的泌尿系统及其功能   总被引:8,自引:4,他引:8  
曾嶒 《水生生物学报》1987,11(1):i001-i002
黄鳝腹腔左侧有盲端的中空管状结构,不是退化性腺,而是十分特化的长管囊膀胱。膀胱内壁具大量发达的绒毛,绒毛表面是移行上皮。在绒毛内部或基部有丰富的血管,因此该管囊膀胱不仅可贮存尿液,而且可能对水分等有重吸收作用。在中肾管与膀胱相接处,膀胱腔背侧出现一条明显的纵行皱襞,即在其横切面上观为巨绒毛。巨绒毛形成的原因,主要是中肾管移入膀胱壁所致。中肾管在巨绒毛内移行一程后才开口于膀胱。因此,黄鳝的生殖腺不是一对,而是一个,位于腹腔右侧。黄鳝肾脏细长,呈“丫”,在腹腔背侧,紧贴脊椎。前端为头肾,无肾单位,仅是造血器官。中肾有类似于哺乳类的肾小体,但数量较少,主要分布在肾脏周缘。肾小管包括颈段、初级近曲小管、次级近曲小管、初级远曲小管和次级远曲小管。两中肾管位于两肾叶腹内侧,其上皮间或是假复层柱状上皮,间或是移行上皮。前者含有许多杯状细胞,并可见到顶浆分泌的现象。中肾的肾小管间组织是大量的红细胞样组织,头肾似具有贮存或释放刚成熟的红细胞的组织结构,因此黄鳝肾脏可能是体内主要的造血器官。  相似文献   
966.
关于种群数量波动的内在调节机制,现今已有大量的实验种群资料证明大多数小型啮齿类种群具有内部调节的反馈系统,但对自然种群的研究至今报道较少,涉及的鼠种为数不多,其中关于Christian(1964)的行为-内分泌  相似文献   
967.
豆小娟  李红  刘芳  龙益军 《生物磁学》2012,(28):5539-5541
目的:探讨护理干预对成年女性压力性尿失禁患者的影响。方法:在患者自愿参与的情况下,随机抽取浏阳市市区80名有压力性尿失禁症状的成年女性,对她们进行护理干预,并对干预效果进行评价。结果:护理干预后,患者压力性尿失禁发作次数显著减少,盆底肌肉张力显著提高,漏尿量显著减少。结论:护理干预可减轻成年女性压力性尿失禁症状,减轻患者的身心痛苦,提高压力性尿失禁患者的生活质量。  相似文献   
968.
Mouse urine contains an abundance of major urinary proteins, lipocalins, whose roles include slow release of semiochemicals. These proteins are highly polymorphic, with small sequence differences between individual members. In this study, we purified to homogeneity four of these proteins from two strains of inbred mice and characterized them by mass spectrometry. This analysis has led to the discovery of another variant in this group of proteins. Three of the polymorphic variants that map to the surface have no effect on the binding of a fluorescent probe in the binding cavity, but the fourth, characterized by a Phe to Val substitution in the cavity, shows a substantially lower affinity and fluorescence yield for the probe. These results are interpreted in light of the known crystal structure of the protein and molecular modeling calculations, which rationalize the experimental findings. This work raises the possibility that the calyx-binding site can show specificity for different ligands, the implications of which on pheromone binding and chemical communication are discussed.  相似文献   
969.
Physiological responses to handling in the turbot   总被引:6,自引:1,他引:6  
Turbot Scophthalmus maximus were cannulated via the afferent branchial artery and were either net-confined in sea water or in air for 9 min to monitor the stress response of a hatchery-reared marine flatfish. No mortality was observed. Aerial exposure appeared to mobilize plasma free fatty acids and stimulate the interrenal tissue but had no effect on circulating glucose or lactate levels. This pattern was qualitatively similar to that induced by net-confinement in sea water, although the magnitude and duration of the changes were more marked in the turbot handled in sea water. Aerial exposure had no effect on plasma osmolality, protein, or Cl concentrations and only a minor effect on plasma Na+ concentrations, which was in sharp contrast to the ionoregulatory disturbance noted in turbot which were net-confined in sea water. However, plasma K+ and cortisol concentrations were similarly elevated by both handling procedures. The results from these experiments suggest that whilst similarities with the salmonid physiological stress response are apparent, the lack of a plasma glucose response may represent a fundamental difference in turbot stress physiology.  相似文献   
970.
本文旨在研究导尿管相关尿路感染病原菌多重耐药与生物膜表型和毒力因子的相关性。选取2018年1月至2019年12月于沈阳市第四人民医院住院期间出现导尿管相关尿路感染的患者为研究对象,收集尿液培养标本,使用全自动微生物鉴定仪和纸片扩散法进行菌株鉴定和药敏试验。根据药敏试验结果,将大肠埃希菌分为多重耐药组和非多重耐药组。紫外分光光度法测定多重耐药组和非多重耐药组大肠埃希菌的生物膜附着力。PCR法分析多重耐药组和非多重耐药组参与大肠埃希菌4种毒力因子(黏附素、保护素、细胞毒素、铁载体)编码的16种基因表达水平。 共收集156例患者的尿液,并从尿液培养标本中分离出病原菌172株,其中大肠埃希菌97株(56.7%)占比最多。药敏试验结果显示,多重耐药组大肠埃希菌对各类抗菌药物的耐药率均超过60%。与非多重耐药组相比,多重耐药组大肠埃希菌生物膜阳性率差异有统计学意义(P<0.05),附着力强度等级差异也有统计学意义(P<0.05)。多重耐药组大肠埃希菌与黏附素相关4种毒力基因fimH、sfa、afa、iha表达明显高于非多重耐药组,差异具有统计学意义(P<0.05)。导尿管相关尿路感染病原菌的多重耐药与毒力因子参与产生强附着力生物膜表型有关。  相似文献   
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