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101.
按照犬瘟热(CDV)N基因序列,设计合成了特异性引物和探针,经各反应条件的优化,建立了Real—time荧光定量RT—PCR技术,对细胞培养物、肝脏、肺脏、脑、脾脏、淋巴结以及鼻腔拭子等组织病料中的CDV进行了特异性检测和敏感性试验。同时,利用建立的Real—time荧光定量RT—PCR方法与常规RT—PCR以及韩国BIOINDIST生产的BITRAPIDCDV检测试剂盒对57份临床样品进行了检测。结果:用20pmol/mL的引物浓度各luL和20pmol/mL的探针浓度0.3uL,获得的荧光信号最强,曲线平滑。敏感性高,可检测到1.24×3ng/uL的病毒RNA;特异性强,与NDV、AIV、NiPV等RNA病毒不发生交叉反应。试验重复性的变异系数(CV)分别为2.3%、2.5%和4.2%;与常规RT—PCR和BIOINDIST生产的BITRAPIDCDV检测试剂盒相比较,该方法具有快速、特异、敏感、可定量,并可同时检测大量样品等优点。  相似文献   
102.
Oxidative damage in the brain may lead to cognitive impairments in aged humans. Further, in age-associated neurodegenerative disease, oxidative damage may be exacerbated and associated with additional neuropathology. Epidemiological studies in humans show both positive and negative effects of the use of antioxidant supplements on healthy cognitive aging and on the risk of developing Alzheimer disease (AD). This contrasts with consistent behavioral improvements in aged rodent models. In a higher mammalian model system that naturally accumulates human-type pathology and cognitive decline (aged dogs), an antioxidant enriched diet leads to rapid learning improvements, memory improvements after prolonged treatment and cognitive maintenance. Cognitive benefits can be further enhanced by the addition of behavioral enrichment. In the brains of aged treated dogs, oxidative damage is reduced and there is some evidence of reduced AD-like neuropathology. In combination, antioxidants may be beneficial for promoting healthy brain aging and reducing the risk of neurodegenerative disease. Special issue article in honor of Dr. Akitne Mori.  相似文献   
103.
A detailed investigation has been carried out about the serological profiles of groups of dogs experimentally infected with metacyclic (MT) or blood (BT) trypomastigotes of Berenice-78 Trypanosoma cruzi strain. Peripheral blood was collected from infected dogs and uninfected controls, weekly during 35 days following the acute phase of infection, and immunoglobulin profiles were determined by ELISA. Dogs infected with BT exhibited unaltered levels of IgG2, increases in IgM, IgE, IgA, IgG and IgG1. In contrast, dogs infected with MT presented unaltered levels of IgE and IgG1 and an increase in IgM, IgA, IgG and IgG2 levels. Compared with the MT group, animals infected with BT showed significant increases in IgM on days 7, 14 and 28, in IgA on days 7, 14 and 21, in IgE on days 7 and 14, in IgG on days 14 and 28, and in IgG1 on days 7, 14 and 21. Parasitemia levels of the infected animals were measured over the same time period. No correlations were found between the immunoglobulin profiles and the parasitemia levels. The results demonstrated that the inoculum source (BT or MT) influence the immunoglobulin isotype profile that may drive distinct outcome of acute canine Chagas disease.  相似文献   
104.
表达狂犬病病毒糖蛋白的重组犬2型腺病毒的构建   总被引:3,自引:0,他引:3  
本试验以犬2型腺病毒全基因组重组质粒pPolyⅡ-CAV-2及其E3区重组质粒pVAX-E3为基础,通过DraⅢ和SspⅠ双酶切,缺失第25097bp-26141bp共1044bp的E3区片段,按与编码链相同转录方向插入由CMV启动子、狂犬病病毒SRV\-9株糖蛋白基因、SV40 polyA基因构成的总长2424bp的表达盒,获得重组基因组质粒pPolyⅡ-CAV-2-CGS(34.7kb).以AscⅠ和ClaⅠ双酶切,游离重组基因组(32.7kb),在脂质体Lipofectamine TM 2000介导下,转染MDCK细胞系,获得了E3缺失区携带狂犬病病毒糖蛋白表达盒的重组犬2型腺病毒CAV-2-CGS.Western印迹试验表明,CAV-2-CGS表达了狂犬病病毒糖蛋白.初步接种试验显示,重组病毒可以诱导犬产生狂犬病病毒特异性抗体.  相似文献   
105.
目的建立荧光定量PCR方法,检测犬不同组织中SLAM受体mRNA的表达水平。方法以犬GAPDH为内参基因采用△△ct法,分析SLAM受体mRNA在犬体内不同组织中的表达。结果此方法有较高的重复性,变异系数在0.89%-2.35%。以SLAM受体在心脏的表达为1倍值,结果显示受体mRNA在脾脏中表达最高,为38.49倍;肺门淋巴结、肠系膜淋巴结、腹股沟淋巴结中表达次之,分别为9.13、8.58、6.24倍;膀胱中表达最低。结论成功建立了检测SLAM受体mRNA在不同组织中表达水平的荧光定量PCR检测方法。  相似文献   
106.
贵州普定穿洞出土的一化石智人颅盖骨   总被引:1,自引:0,他引:1       下载免费PDF全文
黄象洪 《人类学学报》1989,8(4):379-381
1976年南京大学地理系俞锦标教授等在贵州省普定县进行野外调查时,在穿洞发现骨化石、烧骨、灰烬等。后于1979年,在有关方面的配合下,在洞口进行试掘,掘到1.5米深处,获得了一个破碎的智人颅盖骨化石。颅盖骨附近还有右上颌骨半块、单独的右上中门齿一枚。与头骨化石共生的有一些骨角器、烧骨和少量石器。这些材料俞教授等已作过报道和初步研究(俞锦标等,1983;俞锦标,1984)。不久前,俞教授把头盖骨化石供本人作古人类学研究之用,现报告如下。  相似文献   
107.
Embryonic stem cells (ESCs) are permanent cell lines that can be maintained in a pluripotent, undifferentiated state. Appropriate environmental stimuli can cause them to differentiate into cell types of all three germ layers both in vitro and in vivo. Embryonic stem cells bear many opportunities for clinical applications in tissue engineering and regenerative medicine. Whereas most of our knowledge on the biology and technology of ESCs is derived from studies with mouse cells, large animal models mimicking important aspects of human anatomy, physiology, and pathology more closely than mouse models are urgently needed for studies evaluating the safety and efficacy of cell therapies. The dog is an excellent model for studying human diseases, and the availability of canine ESCs would open new possibilities for this model in biomedical research. In addition, canine ESCs could be useful for the development of cell-based approaches for the treatment of dogs. Here, we discuss the features of recently reported canine embryo-derived cells and their potential applications in basic and translational biomedical research.  相似文献   
108.
Despite the high prevalence of primary uterine inertia in whelping bitches, the underlying pathogenesis remains unclear. The objectives were to i) determine serum concentrations of total calcium, ionized calcium (iCa), parathyroid hormone (PTH), and blood pH in normally whelping bitches throughout the peri-parturient period; and ii) investigate relationships among iCa, PTH, and acid-base status, and the role that they and oxytocin may have in the underlying pathogenesis of canine uterine inertia. Bitches were randomly selected from a population of German Shepherd Dog bitches with a history of uncomplicated parturition (Group 1; n = 10), and from a population of Labrador bitches with a clinical history of an increased incidence of uterine inertia and stillbirths (Group 2; n = 20). Jugular blood samples were collected daily from -4 d to the onset of whelping (t = 0 h), and then every 4 h until the last pup was born. Overall, bitches from Group 2 had higher mean ± SEM serum concentrations of PTH (4.72 ± 2.45 pmol/L, P < 0.001), lower iCa (1.31 ± 0.08 pmol/L, P < 0.05), and higher venous pH (7.41 ± 0.03, P < 0.005) than bitches from Group 1 (2.9 ± 1.44 pmol/L, 1.38 ± 0.06 mmol/L, and 7.33 ± 0.02, respectively) during the periparturient period. However, there was no significant difference between Groups 1 and 2 for serum oxytocin concentrations during the periparturient period (45.5 ± 40 and 65.5 ± 82 pg/mL). We inferred that low iCa resulting from a rising pH and decreasing PTH during the periparturient period may have contributed to decreased uterine contractility and increased risk of stillbirths. Therefore, manipulating the cationic/anionic difference in diets of pregnant bitches, similar to the bovine model for hypocalcamia, may reduce the incidence of stillbirths in the bitch.  相似文献   
109.
目的建立犬CDV抗体ELISA检测方法。方法培养vero细胞,接种CDV病毒,制备vero正常抗原和CDV特异抗原,滴定酶结合物和抗原最佳工作浓度,并进行精密性、敏感性、稳定性、特异性实验。结果正常、特异抗原和酶结合物最佳工作浓度分别为1∶32 000、10μg/mL和1∶8 000;正常、特异抗原批内变异系数分别为9.1%和5.8%,批间平均变异系数分别为8.8%和6.6%;检测灵敏度为1∶2 560;与犬细小病毒(CPV)、犬肝炎病毒(ICHV)均无交叉反应。稳定性试验相对偏差小于25%。结论建立的ELISA方法重复性、稳定性好,特异性、敏感性强。可用于犬CDV抗体的检测。  相似文献   
110.
Versican plays a role in tumor cell proliferation and adhesion and may also regulate cell phenotype. Furthermore, it is one of the pivotal proteoglycans in mesenchymal condensation during prechondrogenesis. We have previously demonstrated accumulation of versican protein in myoepithelial-like spindle cell proliferations and myxoid tissues of complex and mixed mammary tumors of dogs. The objective of this study was to investigate whether the high expression of versican relates to prechondrogenesis in these tissues. Therefore, we aimed to identify cartilage markers, such as collagen type II and aggrecan both at mRNA and protein level in relation to versican. The neopitope of chondoitin-6-sulphate (3B3) known to be generated in developing cartilage has been investigated by immunohistochemisty and a panel of antibodies were used to characterize the phenotype of cells that are involved in cartilage formation. In addition, co-localization of versican with hyaluronan and link protein was studied. RT-PCR revealed upregulation of genes of versican, collagen type II and aggrecan in neoplastic tissues, especially in complex and mixed tumors. Immunohistochemistry showed the expression of cartilage biomarkers not only in the cartilagenous tissues of mixed tumors, but also in myoepitheliomas and in the myoepithelial-like cell proliferations and myxoid areas of complex and mixed tumors. The results show the cartilagenous differentiation of complex tumors and myoepitheliomas and indicate that the myxoid tissues and myoepithelial-like cell proliferations are the precursor tissues of the ectopic cartilage in mixed tumors. Furthermore, we suggest that cartilage formation in canine mammary tumors is a result of (myo)epithelial to mesenchymal transition.  相似文献   
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