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41.
K Tamura Y Aratake T Kotani M Seita S Ohtaki 《American journal of clinical pathology》1985,84(1):44-48
The specific immunophenotypic characterization of the hematologic malignant diseases has been obtained most commonly by the immunofluorescent technic. It requires a microscope with illuminator or the expensive flow cytometer that usually precludes morphologic assessment. It was compared with the indirect rosette assay and the immunoperoxidase study, which allowed both immunologic and morphologic assessment. These three technics appeared to be comparable quantitatively, and the latter two technics utilizing cytospin preparations were applied sequentially to the leukemic cells of adult T-cell leukemia with a complex phenotype (OKT4+/OKT8+) and successfully displayed the double markers on each leukemic cell. 相似文献
42.
Katagiri H Kawai Y Sugizaki N Sakai K Handa M Okamoto S Watanabe K 《Rinsho byori. The Japanese journal of clinical pathology》2003,51(6):516-521
Thrombotic thrombocytopenic purpura(TTP) is a multisystem disorders characterized by thrombocytopenia, microangiopathic hemolytic anemia associated with red cell fragmentation, and neurological and renal symptoms. Plasma of patients with TTP has been shown to contain unusually large von Willebrand factor(vWF) multimers that may cause platelet agglutination in vivo. Recently, a metalloprotease responsible for cleavage of vWF multimers has been isolated from normal human plasma and was found to be deficient in some patients with TTP. We examined the activity of the vWF-cleaving protease(vWF-CP), by modified Furlan's method, in plasma from patients with a familial TTP, 3 acquired TTP, 4 thrombotic microangiopathy(TMA) and 2 veno-occlusive disease(VOD) associated after allo-BMT. Diluted plasma samples of patients were incubated with protease-free vWF purified from normal human plasma, in the presence of urea and barium ions. The extent of vWF degradation was assayed by electrophoresis in SDS-agarose gels and immunoblotting. Activity of vWF-CP from 12 normal plasma have been shown as 77-180%(average 115%), whereas, no vWF-CP(below 5%) was observed in plasma from familial TTP, before and after plasma exchange, although FFP infusion therapy has been effective for this patient to recover thrombocytopenia. In 3 acquired TTP, 2 patients showed lack of vWF-CP activity in plasma, and inhibitors against vWF-CP have been elucidated by plasma cross-mixing test. After extensive plasma exchange and FFP infusion followed by corticosteroid therapy, normal vWF-CP was recovered in plasma from 2 acquired TTP patients. Among BMT patients, plasma from 4 BMT-TMA showed normal vWF-CP activities as 55-111%, whereas plasma from 2 BMT-VOD revealed low vWF-CP activity, as 24% and 37%, respectively. Thus, measurement of vWF-CP is crucial to predict differentiation of primary forms of TMA to establish the pathogenesis in varied endothelial dysfunction. 相似文献
43.
Mori S Endo M Nishizawa K Ohno M Miyazaki H Tsujita K Saito Y 《Physics in medicine and biology》2005,50(22):N359-N370
The prototype cone-beam CT (CBCT) has a larger beam width than the conventional multi-detector row CT (MDCT). This causes a non-uniform angular distribution of the x-ray beam intensity known as the heel effect. Scan conditions for CBCT tube current are adjusted on the anode side to obtain an acceptable clinical image quality. However, as the dose is greater on the cathode side than on the anode side, the signal-to-noise ratio on the cathode side is excessively high, resulting in an unnecessary dose amount. To compensate for the heel effect, we developed a heel effect compensation (HEC) filter. The HEC filter rendered the dose distribution uniform and reduced the dose by an average of 25% for free air and by 20% for CTDI phantoms compared to doses with the conventional filter. In addition, its effect in rendering the effective energy uniform resulted in an improvement in image quality. This new HEC filter may be useful in cone-beam CT studies. 相似文献
44.
45.
Somatic Mutation in Human B-Cell Tumors 总被引:15,自引:0,他引:15
Ronald Levy Shoshana Levy Michael L. Cleary William Carroll Shinichiro Kon Jeffrey Bird Jeffrey Sklar 《Immunological reviews》1987,96(1):43-58
46.
Kiyoshi Kasai Yuichi Sato Toru Kameya Hayato Inoue Hirokuni Yoshimura Shinichiro Kon Kokichi Kikuchi 《The Journal of pathology》1994,174(4):257-265
To evaluate the presence of Epstein–Barr virus (EBV) in lung cancers of Japanese patients, 81 lung cancers were examined using a highly sensitive in situ hybridization (ISH) method, employing an antisense oligonucleotide probe for EBV-encoded small nuclear RNA-1 (EBER). EBER1 expression was demonstrated in one poorly differentiated squamous cell carcinoma associated with marked lymphoid stroma (PDSCC-LS), two well differentiated adenocarcinomas, and two moderately differentiated squamous cell carcinomas, but was not detectable in other lung cancers, including small cell carcinomas. Unlike lymphoepithelioma-like undifferentiated carcinoma (LELC) of the lung, the PDSCC-LS consisted of poorly differentiated cells with distinct cell borders and nuclei with a coarse chromatin pattern and some prominent nucleoli. Most of the cancer cells expressed intense EBER1 signals. Although small to moderate numbers of cells positive for EBER1 were present in two adenocarcinomas and two squamous cell carcinomas, EBER1 signals varied in intensity and number in these four cases. Although polymerase chain reaction (PCR) and Southern blot hybridization with a 32P-labelled probe internal to the primers were conducted to detect the EBV genome in 24 lung cancers, including five EBER1-positive cases, the genome was found to be positive in the five cases with EBER1-positive staining, including the PDSCC-LS, two adenocarcinomas and two squamous cell carcinomas, but not in the other cases. This study indicates that the morphological features of EBV-associated lung cancers are not restricted to the typical LELC type. 相似文献
47.
Ramp rate of blood pressure changes does not affect aortic afferent sensitivity in anesthetized rats
Hidefumi Waki Tsuyoshi Shimizu Masao Yamasaki Kiyoaki Katahira Shinichiro Katsuda Jaimie W. Polson Masanobu Maeda 《Neuroscience letters》2008
To investigate whether the rate of change in blood pressure affects the sensitivity of the aortic baroreceptor afferent response, the change in aortic nerve activity (ANA) to two different rates of ramp increase in mean blood pressure (MBP), elicited by phenylephrine administration, was determined in the rat under urethane (1.5 g kg−1) anesthesia. The sensitivity of the increase in ANA following a rapid (average ramp rate, 9.14 ± 0.60 mmHg s−1, n = 11) or gradual (1.78 ± 0.24 mmHg s−1, n = 11) increase in MBP was 2.03 ± 0.14% and 1.81 ± 0.20% of baseline mmHg−1, respectively. These values were not significantly different from each other (P = 0.16). Furthermore, we found no correlation between the rate of ramp increase in MBP and the sensitivity of the increase in ANA (r = 0.24, P = 0.29, n = 22). These results suggest that, at least within the normal physiological range of MBP, the rate of the ramp change in blood pressure does not affect aortic baroreceptor afferent sensitivity in the anesthetized rat. 相似文献
48.
Diagnostic utility of galectin-3 and CD26/DPPIV as preoperative diagnostic markers for thyroid nodules 总被引:3,自引:0,他引:3
Aratake Y Umeki K Kiyoyama K Hinoura Y Sato S Ohno A Kuribayashi T Hirai K Nabeshima K Kotani T 《Diagnostic cytopathology》2002,26(6):366-372
The aim of this study was to search for diagnostic markers that could correctly identify thyroid nodular lesions requiring urgent surgical treatment. We investigated whether galectin-3 and dipeptidyl peptidase IV (CD26/DPPIV) could be potential markers for improving the diagnostic accuracy of conventional cytology. Seventy-nine patients with histologically proven thyroid diseases were analyzed. The immunocytochemical staining results showed galectin-3 expression in neoplastic cells of all 37 papillary carcinomas, five of six follicular carcinomas, all three anaplastic carcinomas, one of three medullary carcinomas, and two of 14 follicular adenomas. All 16 adenomatous goiters were negative for galectin-3 immunostaining. On the other hand, all 37 papillary carcinomas, all six follicular carcinomas, and one of three anaplastic carcinomas revealed CD26/DPPIV expression, whereas all three medullary carcinomas were negative. Among benign thyroid lesions, four of 14 follicular adenomas and two of 16 adenomatous goiters exhibited varying degrees of immunoreactivity for CD26/DPPIV. RT-PCR analysis demonstrated overexpression of galectin-3 and CD26/DPPIV mRNAs in all six papillary and all three follicular carcinomas analyzed, whereas the mRNA expressions of these molecules were barely or not detectable in benign thyroid lesions and normal thyroid tissues, except for one case of follicular adenoma. In conclusion, we demonstrate that galectin-3 and CD26/DPPIV were consistently coexpressed at protein and mRNA levels in differentiated thyroid carcinomas. We propose that combined immunostaining for galectin-3 and CD26/DPPIV in the preoperative evaluation of thyroid nodules may play a role in accurate cytodiagnosis. 相似文献
49.
T Umemoto T Ota H Sagawa K Kato H Takada M Tsujimoto A Kawasaki T Ogawa K Harada S Kotani 《Infection and immunity》1981,31(2):767-774
A peptidoglycan layer of Treponema pallidum kazan was isolated by solubilization of whole cells with 1% warm sodium dodecyl sulfate and subsequent digestion of an insoluble residue with proteases. Electron microscopy revealed that the peptidoglycan was isolated as a single-layered sacculus of less than 5 nm in thickness, freed from axial filaments and an envelope sheath. An isolated peptidoglycan fraction was mainly composed of glucosamine, muramic acid, alanine, glutamic acid, ornithine, and glycine in molar ratios of 0.65:0.68:1.63:1.00:0.75:1.03. Amino (N)- and carboxyl (C)-terminal amino acid analyses suggested the involvement of at least a part of the glycine residue in cross-linking between the amino group of ornithine residue at one strand of the stem peptide subunit and the carboxyl group of alanine of the neighboring strand. The treponemal peptidoglycan lacked the immunoadjuvant activity both to stimulate antibody production and to induce delayed-type hypersensitivity against ovalbumin, as well as the properties necessary to stimulate guinea pig and mouse splenocytes and guinea pigs peritoneal macrophages, unlike the cell walls or peptidoglycans (group A type of Schleifer and Kandler's classification, Bacteriol. Rev. 36:407-477, 1972) isolated from many bacterial species parasitic to the mammal. However, the peptidoglycan activated the human complement system through the alternative pathway, as well as the classical one, and caused a liberation of 5-hydroxytryptamine in rabbit blood platelets in a similar manner to the cell wall peptidoglycans of both group A and B types. 相似文献
50.
Absence of either gastric or intestinal phenotype in microscopic differentiated gastric carcinomas 总被引:6,自引:0,他引:6
Kawachi H Takizawa T Eishi Y Shimizu S Kumagai J Funata N Koike M 《The Journal of pathology》2003,199(4):436-446
Differentiated gastric carcinoma (DGC) corresponds roughly to the intestinal type of gastric carcinoma described by Laurén. It has been suggested that DGCs arise from intestinalized gastric mucosa, but recent findings regarding their mucin expression do not support this hypothesis. To evaluate the histogenetic relationship between DGCs and intestinal metaplasia, lesions that are as small as possible should be examined. Twenty-five DGCs, ranging in their greatest dimension from 0.4 to 2.7 mm, were collected and divided into two groups by size. Group A consisted of 13 lesions less than 1.4 mm across, and group B of 12 lesions 1.4 mm or more. The presence of mucin and a brush border was assessed by immunostaining with antibodies against human gastric mucin, pyloric-gland-type mucin, Muc-2 glycoprotein, and CD10 antigen, and the lesions were classified as having the gastric phenotype (G-type), intestinal phenotype (I-type), mixed gastric and intestinal phenotype (M-type), or null phenotype (N-type). Thirteen (52%) of the 25 lesions were N-type, 5 (20%) lesions were G-type, 5 (20%) were I-type, and 2 (8%) were M-type. Group A had a larger proportion of N-type lesions than B (10/13, or 77%, vs. 3/12, or 25%; p = 0.027, chi-square test for proportions). Group B had a larger proportion of G-type lesions than A (5/12, or 42%, vs. 0/13, or 0%; p = 0.033). The phenotypes of the carcinomas and their surrounding mucosa were unrelated. Therefore, DGCs may arise from gastric mucosa affected by intestinal metaplasia or not, without having either the gastric or intestinal phenotype. 相似文献