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51.
鸡后根神经节多巴胺细胞在体及体外培养中的免疫细胞化学观察 总被引:2,自引:0,他引:2
应用免疫细胞化学PAP法,研究了鸡胚和雏鸡后根神经节细胞内多巴胺递质的表现与胚胎发育过程中的变化,并在细胞培养条件下研究了周围靶组织——皮肤对后根节细胞胚胎发育的影响。鸡后根节细胞内多巴胺的免疫反应最先出现于E_(10),只占后根节细胞的0.8%,E_(18)时达5.6%,出壳后雏鸡为8.6%。在鸡后根节内,多巴胺免疫反应阳性细胞主要为较大的A类细胞,和极少较小的B类细胞。免疫反应阳性的周围神经末梢位于皮肤和交感干内。当取自E_9的鸡胚后根节细胞经7天培养后,部分神经细胞出现多巴胺免疫反应阳性;而取自E_6的鸡胚后根节细胞虽经10天培养后仍为免疫反应阴性;然而,将取自E_6后根节细胞与皮肤组织联合培养10天后,少量神经细胞及轴突出现多巴胺免疫阳性反应。作者认为:鸡后根节多巴胺细胞在胚胎时期的发育有赖于周围靶组织的作用。 相似文献
52.
In an immunocytochemical study of 41 human lung tumours we have shown that Langerhans cells can be reliably identified using the anti-CD1 monoclonal antibody NA1/34. Langerhans cells are present in all the main varieties of human lung tumour although they are infrequent in both small cell carcinoma and carcinoid tumour. There is considerable variation in numbers of Langerhans cells in both adenocarcinomas and squamous cell carcinomas. In this study tumours were divided into those with high numbers of Langerhans cells (greater than 2 per high power field) and those with low numbers (less than 2 per high power field). Analysing these results against patient survival showed a markedly worse survival in those tumours with a high number of Langerhans cells for all the tumours as a single group and for squamous cell carcinoma as a single entity. 相似文献
53.
Several techniques have been developed for protein immunolocalization in meiotic cells. However, most of them include treatments that lead to cell disruption and are only suitable for prophase-I cells. We describe a novel squash procedure of cell preparation for protein immunolabelling of different meiotic stages. This procedure is an alternative to both cryosectioning and whole spreading procedures. We present results obtained in mouse spermatocytes with three different antibodies: the MPM-2 mAb against mitotic phosphoepitopes, an anticentromere serum and a polyclonal serum against the SCP3 protein of the axial elements and lateral elements of the synaptonemal complex. The procedure was tested for single and double immunolabelling. With this technique a large number of cells at different meiotic stages can be analysed. Cell stages are easily identified and cell and chromosome structures are preserved. Thus, it allows the study of chromosome behaviour and the relations hips between the different structural elements of the cell throughout meiotic divisions. Our procedure is also suitable for three-dimensional (3D) analyses and proved to be reliable in a wide range of systems including insects and mammals. In addition, the procedure may be interesting to obtain a rapid immunological diagnosis. 相似文献
54.
Follicular lymphoma is a relatively uncommon type of non-Hodgkin's lymphoma (NHL) thought to derive from follicular center cells. There are limitations to fine-needle aspiration in the diagnosis of follicular NHL, and very few studies are available on it. We describe here the cytomorphologic features of eight biopsy-proven cases of follicular NHLs and five biopsy-proven cases of intermediate-grade NHLs. Five cases of reactive lymphoid hyperplasia (RLH) diagnosed on cytology were also studied cytomorphologically. Image morphometry was done in follicular and intermediate-grade NHLs, immunocytochemistry was done in follicular and intermediate-grade NHLs, and immunocytochemistry for bcl-2 expression was studied in five cases of follicular NHLs. The aspirate smears of follicular NHL showed the presence of higher grades, many to abundant (++ to +++) monomorphic lymphoid aggregates, with an increased number of mast cells. Lymphohistiocytic tangles and tingeable body macrophages were not observed in any of the cases. Cytomorphologically, all the cases of intermediate-grade NHL showed a predominantly monomorphic population of lymphoid cells with absent or few grades (+) of lymphoid aggregates. Image morphometric data analysis of each cell parameter for follicular and intermediate-grade NHLs were found to be statistically insignificant (P > 0.05) and hence of little help in diagnosis of follicular vs. low-grade NHLs. Immunocytochemistry for bcl-2 expression in follicular NHL showed variable results, ranging from 0-90% (expressed as bcl-2 index). Certain characteristic cytomorphological features such as the presence of monomorphic lymphoid cell aggregates and an increased number of mast cells are soft indicators for the diagnosis of follicular NHL on aspiration smears. Immunocytochemistry for bcl-2 expression may be of help in cases with clinical and cytological suspicion of lymphoma. Image morphometry has a small role in this regard. 相似文献
55.
Günter Klöppel Thomas Dreyer Sebastian Willemer Horst F. Kern Guido Adler 《Virchows Archiv : an international journal of pathology》1986,409(6):791-803
Summary Human acute pancreatitis results from an autodigestive process frequently associated with alcohol abuse, gall stone disease and shock. Peripancreatic fat necrosis was identified as one of the earliest visible lesions, whereas acinar cell necrosis and haemorrhage were regarded as secondary changes. To examine the alterations in acinar cells in more detail, their enzyme content and fine structural features were studied immunocytochemically using antisera against -amylase, lipase, trypsin, chymotrypsin and pancreatic stone protein, and electronmicroscopically in pancreatic tissues from patients with severe acute pancreatitis. Peripheral acinar cells in the immediate vicinity of fat necrosis were found to be heavily degranulated, while acinar cells at some distance of necrosis fully retained their enzyme content. Other frequent changes of the acinar cells included cuboidal transformation, loss of microvilli, increased occurrence of autophagosomes, and formation of enlarged acinar lumina. As there was no apparent cell membrane leakage or rupture of duct lumina, it is concluded that the acinar cells adjacent to fat necrosis release their granules by undirected basolateral extrusion. The findings thus suggest that one of the basic defects in acute pancreatitis is the uncontrolled release of enzymes from peripheral acinar cells into the interstitial space which, in turn, presumably by the action of lipase, leads to autodigestive fat necrosis.Dedicated to Prof. Dr. G. Seifert on the occasion of his 65th birthdayPresented in part at the Second International Symposium on the Classification of Pancreatitis, Marseille, 1984, and at the Meeting of the European Pancreatic Club, Manchester, 1985 相似文献
56.
Postnatal development of the innervation and paraganglia in the porcine pulmonary arterial bed 总被引:2,自引:0,他引:2
The innervation of the pulmonary trunk and pulmonary arterial bed was studied in 17 pigs from birth to 6 months of age. After birth, the pulmonary trunk and extra- and intra-pulmonary arteries contained neurofilament and protein gene-product-immunoreactive nerve fibres in both the adventitia and media. The density of nerve fibres increased from birth to 2 months, this being most marked during the first 2 weeks of life. Most of the fibres in the media were presumed to be sympathetic in origin as they contained both neuropeptide tyrosine and tyrosine hydroxylase immunoreactivity. Fibres were associated with the vasa-vasorum and vascular smooth muscle running around the vessel, between the elastic laminae and smooth muscle cells, in the outer two-thirds of the media. Vasoactive intestinal polypeptide and calcitonin gene-related peptide-immunoreactive nerve fibres were found to be associated with the pulmonary trunk and extra-pulmonary artery, but generally not with the intra-pulmonary arteries. Tyrosine hydroxylase immunoreactivity was detected in the glomus cells at birth, but peptide immunoreactivity (enkephalin) was not demonstrated in paraganglia until 14 days of age. Adaptation to extra-uterine life is associated with rapid development changes in the innervation of the pig pulmonary trunk, extra- and intra-pulmonary arteries and in the expression of peptide immunoreactivity in both nerve fibres and glomus cells. These changes may have a role in the postnatal adaptation of the pulmonary circulation. 相似文献
57.
Zaitsev S Buchwalow I Haberland A Tkachuk S Zaitseva I Haller H Böttger M 《Acta histochemica》2002,104(1):85-92
Previously, we have shown that the transgene expression in the endothelial cell line ECV 304 strongly depends on the presence of low concentrations of Ca2+. However, it remained unclear, which transfection steps are controlled by Ca2+ ions. In the present study, we constructed transfection complexes of digoxigenin-labelled DNA and FITC-labelled histone H1. We monitored the pathway of these complexes with the use of anti-digoxigenin and anti-cathepsin B antibodies and immunofluorescence microscopy. Double labelling of DNA and cathepsin B permitted the localization of transfection complexes into endosomes/lysosomes which suggests an uptake of transfection complexes via endocytosis. It was also found that the uptake of transfection complexes by the cells was independent of the presence or absence of Ca2+ ions in the transfection medium. On the other hand, the presence of Ca2+ in the transfection medium dramatically changed the composition of the transfection complexes inside the endosome/lysosome compartment, which resulted in a strong reduction of H1 binding to DNA. Presence of Ca2+ in the postincubation medium for 24 h resulted in release of the transfection complexes with reduced H1 content from the endosomes/lysosomes into the cytosol. In the absence of Ca2+ the transfection complexes practically disappeared. These results allow us to come to the following conclusions: Ca2+ ions control the reorganization of the transfection complexes in endosomes/lysosomes and their release into the cytosol, which is an important prerequisite for transgene expression, whereas uptake of transfection complexes by the cells is not dependent on Ca2+. 相似文献
58.
Candusso ME Luinetti O Villani L Alberizzi P Klersy C Fiocca R Ranzani GN Solcia E 《The Journal of pathology》2002,196(1):44-50
Identification of neuroendocrine differentiation in tumours has important implications for prognosis and therapy. The aim of the present study was to evaluate monoclonal antibodies against synaptic vesicle protein 2 (SV2) as histopathological markers for neuroendocrine differentiation in tumours of the gastrointestinal tract and pancreas. Paraffin blocks from 211 gastrointestinal tumours were examined by immunocytochemistry, using a monoclonal antibody against SV2. Virtually all endocrine tumours of the gastrointestinal tract (11/11 gastric, 53/53 ileal, 16/21 appendiceal, and 22/22 rectal) and pancreas (24/24) were positively labelled. SV2 labelling was also demonstrated in gastrointestinal pacemaker cell tumours (8/8), while adenocarcinomas of the gastrointestinal tract and pancreas were negative, with the exception of occasional adenocarcinomas demonstrating weak SV2 labelling (stomach 1/22, rectum 1/29, and pancreas 0/21). Western blotting of tumour biopsies confirmed expression of SV2 in endocrine tumours of the gastrointestinal tract and pancreas. No relationship was observed between SV2 expression in tumours and hormone production or malignant potential. In conclusion, SV2 is expressed in neuroendocrine tumours of the gastrointestinal tract and pancreas, but not in non-endocrine tumours. The SV2 monoclonal antibody can therefore be used as a general marker for neuroendocrine differentiation in gastrointestinal and pancreatic tumours. 相似文献
59.
神经激肽A免疫反应在哮喘豚鼠脊髓中的定量分析 总被引:1,自引:0,他引:1
用免疫细胞化学ABC法结合显微图像定量分析,研究了神经激肽A(NKA)免疫反应物在哮喘豚鼠脊髓中的分布及其变化。结果表明,NKA免疫反应纤维及终末分布于豚鼠C7~T5段脊髓后角Ⅰ~Ⅲ层和背外侧索核区,NKA样阳性免疫反应物的平均密度在前者为42.2%,后者为37.2%;它们的平均灰度值分别为134.7和92.9,与对照组(平均密度分别为27.2%和24.9%,平均灰度值分别为199.9和129.2)比较均有显著性差别(P<0.01)。这些研究结果提示脊髓内NKA可能参与了哮喘发作的神经病理生理机制,是其发作的重要因素之一。 相似文献
60.
用杂交瘤技术建立了6株能稳定分泌抗阴道毛滴虫单克隆抗体的细胞株,选取其中3株进行了分析。3株单抗的效价分别是:ⅣA12B1和ⅣA22B1为250000ⅡB2A1为1250000。ⅣA12B1和ⅡB2A为IgG3抗体,ⅣA2281为IgGl抗体。位点分析及免疫酶染色发现,ⅣA12B1和ⅣA22B1抗同一抗原决定簇,所针对的抗原主要分布于膜上;ⅡB2A1针对的抗原主要分布于胞浆中。3株单抗针对的抗原均为糖蛋白。特异性试验发现,这3株单抗与人白细胞、阴道上皮细胞、白色念珠菌、大肠杆菌及人毛滴虫均无交叉反应。用制备的单克隆抗体,建立了试断滴虫性阴道炎的胶乳凝集试验(LAT)。研究表明,LAT是一种敏感、特异、简单和快速的方法。 相似文献