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P.G. Vissio A.V. Stefano G.M. Somoza M.C. Maggese D.A. Paz 《Fish physiology and biochemistry》1999,21(2):121-127
The purpose of this study was to determine if there is any association between immunoreactive (ir) gonadotropin-releasing hormone (GnRH) fibers with different pituitary endocrine cell types in the pejerrey, Odontesthes bonariensis. Using a monoclonal antibody raised against mammalian GnRH (mGnRH) (LRH13), ir-GnRH fibers were observed passing through the pituitary stalk and reaching the three areas of the pituitary gland: rostral (RPD) and proximal pars distalis (PPD) and pars intermedia (PI). Double labeled immunocytochemistry showed ir-GnRH fibers in close association with prolactin (PRL)-producing cells in the RPD, growth hormone (GH)-producing cells in the PPD, gonadotropin (GtH)-producing cells in the PPD and the external border of the PI, and with somatolactin (SL)-producing cells in the PI. Our results show, direct morphological evidences of a close association of GnRH fibers with GH, PRL, GtH and SL-expressing cells. These results would suggest that GnRH has a broad role in the regulation of the secretion of different pituitary hormones. 相似文献
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Pathogen development and host responses in wheat spikes of resistant and susceptible cultivars infected by Fusarium culmorum causing Fusarium head blight (FHB), were investigated by means of electron microscopy as well as immunogold labelling techniques. The studies revealed similarities in the infection process and the initial spreading of the pathogen in wheat spikes between resistant and susceptible cultivars. However, the pathogen’s development was obviously more slow in the resistant cultivars as in comparison to a susceptible one. The structural defence reactions such as the formation of thick layered appositions and large papillae were essentially more pronounced in the infected host tissues of the resistant cultivars, than in the susceptible one. β -1,3-glucan was detected in the appositions and papillae. Furthermore, immunogold labelling of lignin demonstrated that there were no differences in the lignin contents of the wheat spikes between susceptible and resistant cultivars regarding the uninoculated healthy tissue, but densities of lignin in host cell walls of the infected wheat spikes differed distinctly between resistant and susceptible cultivars. The lignin content in the cell walls of the infected tissues of the susceptible wheat cultivar increased slightly, while the lignin accumulated intensely in the host cell walls of the infected wheat spikes of the resistant cultivars. These findings indicate that lignin accumulation in the infected wheat spikes may play an important role in resistance to the spreading of the pathogen in the host tissues. Immunogold labelling of the Fusarium toxin DON in the infected lemma showed the same labelling patterns in the host tissues of resistant and susceptible cultivars. However, there were distinct differences in the toxin concentration between the tissues of the susceptible and resistant cultivars. At the early stage of infection, the labelling densities for DON in resistant cultivars were significantly lower than those in the susceptible one. The present study indicates that the FHB resistant cultivars are able to develop active defence reactions during infection and spreading of the pathogen in the host tissues. The lower accumulation of the toxin DON in the tissues of the infected spikes of resistant cultivars which results from the host’s defence mechanisms may allow more intensive defence responses to the pathogen by the host. 相似文献
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Archival formalin-fixed tissues from wild-caught adult blue sharks, Prionace glauca (L.), were used for immunocytochemical detection of proliferating cell nuclear antigen (PCNA), two oncoproteins from the oncogenes c-myc and pan-ras, and a protein product from the tumour suppressor gene p-53. All sharks were caught during summer months between 2000 and 2006 by recreational fishermen off the USA coast in the northwestern Atlantic. The sharks were necropsied on landing and selected organ samples were collected into elasmobranch formalin and processed for paraffin embedding and light microscopy. Paraffin-embedded sections from collected tissue were both stained with haematoxylin and eosin and processed by immunocytochemical techniques using antibodies raised against the PCNA, p-ras, c-myc and p-53 proteins. The lesions examined in this study included two well differentiated adenomatous gastric polyps, a testicular capsular mesothelioma, a gingival fibropapilloma with elements of ameloblastoma, three liver tumours, two pericardial fibropapillomas and six cases of proliferative serositis (pericarditis and peritonitis). Normal and hyperplastic tissues from blue sharks, and human neoplastic tissues served as negative and positive controls, respectively. We detected upregulation of PCNA in many neoplastic, one dysplastic and in some hyperplastic lesions, and positive p-ras and c-myc signals in some of the neoplastic lesions. None of the examined tissues showed positive p-53 signalling. This is the first literature report on immunocytochemical detection of molecular markers of cancer in sharks and in fish of the class Chondrichthyes. 相似文献
67.
【目的】探讨输卵管上皮细胞和基质细胞的体外分离培养方法及在激素刺激下基质细胞对上皮细胞的作用。【方法】通过差速贴壁法体外分离纯化兔输卵管上皮细胞和基质细胞;免疫组织化学染色和免疫荧光染色方法鉴定上皮细胞和基质细胞的类型和纯度;并在无胎牛血清的DMEM/F12培养液和含体积分数15%胎牛血清的DMEM/F12培养液中,分别添加不同浓度的雌激素(17β-E2)和孕激素(P4),比较上皮细胞和基质细胞的增殖情况及其对上皮细胞/基质细胞共培养的影响。【结果】体外成功地分离到兔输卵管上皮细胞和基质细胞;兔输卵管上皮细胞经鼠抗人细胞角蛋白单克降抗体(anti-CK18)免疫组织化学染色后呈阳性,细胞质呈棕色,免疫荧光染色检测其纯度在98%以上;兔输卵管基质细胞经鼠抗人波形蛋白单克降抗体(anti-Vimentin)免疫组织化学染色后呈阳性,细胞质呈棕色,免疫荧光染色检测其纯度在95%以上。17β-E2和P4均能促进兔输卵管上皮细胞和基质细胞的增殖,使其数量明显增加。基质细胞与上皮细胞共培养,上皮细胞增殖较快。【结论】差速贴壁法能够获得纯度较高的输卵管上皮细胞和基质细胞,在17β-E2和P4共同作用下,少量基质细胞能促进上皮细胞生长。 相似文献
68.
为了进一步探讨中华乌塘鳢[Bostrichthys sinensis(Lacépède)]感受性信息素(17α-P和17α,20β-P)的作用机制,以免疫细胞化学(SABC)法进行中华乌塘鳢嗅觉系统孕酮受体的免疫定位和数量分析。结果显示,孕酮受体免疫阳性细胞在性成熟中华乌塘鳢的嗅上皮、嗅神经和嗅球上均有分布,免疫阳性细胞数量由高到低依次为:嗅上皮、嗅球、嗅神经。半定量分析结果表明,中华乌塘鳢嗅觉系统的孕酮受体免疫阳性细胞的数量与其性腺发育程度有关。性成熟雄鱼和雌鱼嗅上皮的免疫阳性细胞数量分别显著或极显著(P<0.05或P<0.01)高于性未成熟雄鱼和雌鱼;性未成熟鱼嗅神经上未发现孕酮受体免疫阳性细胞;性成熟雌鱼嗅球上的免疫阳性细胞数量显著高于性未成熟雌鱼(P<0.05)。本研究证实了硬骨鱼类嗅觉系统中存在孕酮受体免疫阳性细胞。 相似文献
69.
采用ABC免疫细胞化学法,对中华鳖(Trionyx sinensis)胃肠道5-羟色胺(5-HT)细胞和胃泌素(Gas)细胞的分布和形态进行了观测,并比较了冬眠期和活跃期的分布差异。结果显示,5-HT细胞在胃和肠道各段均有分布,在胃分布于胃腺,在肠则分布于黏膜卜皮。在胃的前部和中部,5-HT细胞位于胃腺各部,而在胃的后部,5-HT细胞则主要集中于胃腺的上部和胃小凹底部。在肠道中,由前向后5-HT细胞的分布呈递减趋势,且大部分细胞呈上窄下宽的锥体形、梨形等,顶端伸达肠腔,为开放型内分泌细胞,少数细胞为封闭型。前、中部胃腺中,Gas细胞的分布数量较多,且位于腺细胞之间,一般为开放型。后部胃腺中Gas细胞数量减少。胃黏膜上皮和肠道中未见Gas细胞的分布。与活跃期相比,冬眠期Gas细胞的分布情况变化不大,但5-HT细胞的分布数量显著减少。 相似文献
70.
Immunocytochemical techniques using an antiserum to cod somatolactin (SL) demonstrated the presence of SL cells in the intermediate
lobe of the pituitary in Oncorhynchus tshawytscha. The cells were small in yearling fish. Two groups of maturing fish were studied. In the spring run salmon collected in April
and May during the upstream migration, the SL cells appeared stimulated. In September, during spawning, SL cell stimulation
was maximal with indices of hypertrophy and degranulation often more marked in females than in males. In the other group,
salmon of the fall run collected in the Pacific Ocean in August had well developed gonads, large gonadotropes and abundant
SL cells. In spawning salmon (September) the SL cells were stimulated, mainly in females. However, the final stimulation was
less intense than in spring run spawning fish. The SL cells were smaller, without evident granule release, but still abundant
in spent salmon of the fall run caught at the end of November. Various factors (time spent in rivers before spawning, starvation,
decalcification, stress, hypothalamic influences) were considered which might explain differences between spring and fall
run salmon. These observations suggest that SL may play a role in the control of gonadal maturation in chinook salmon as it
may also do in sockeye and chum salmon previously studied, and that SL cells may be sensitive to the ambient salinity. 相似文献