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31.
Intraglomerular deposition of fibrin/fibrinogen-related antigen in children with various renal diseases. 下载免费PDF全文
H. Kamitsuji S. Sakamoto T. Matsunaga K. Taira S. Kawahara M. Nakajima 《The American journal of pathology》1988,133(1):61-72
The localization of intraglomerular deposits of fibrin (Fb)/fibrinogen (Fg)-related antigen (FRA) in children with various glomerular diseases was determined by an immunohistopathologic method using an anti-Fg antibody capable of detecting FRA, an anti-D-dimer antibody capable of detecting crosslinked Fb (XLFb) and its derivatives (XLFbDP), and by a method using the effect of monochloroacetic acid (MCA) treatment on kidney sections. In proliferative glomerulonephritis (PGN), XLFbs were detected within the capillaries and extension beyond the mesangium was seen in severe PGN. The FRA within the mesangium of minimal or mild PGN was composed of the non-XLFb substance. The FRA within Bowman's space of most PGN had disappeared after MCA treatment, suggesting a non-XLFb substance. The presence of FRA within electron-dense deposits (EDD) suggested that FRA deposits are associated with immune-complex deposits in the glomeruli. 相似文献
32.
Cleavage of human complement component C5 by cysteine proteinases from Porphyromonas (Bacteroides) gingivalis. Prior oxidation of C5 augments proteinase digestion of C5. 下载免费PDF全文
R G Discipio P J Daffern M Kawahara R Pike J Travis T E Hugli J Potempa 《Immunology》1996,87(4):660-667
Since severe periodontitis is characterized by an acute inflammatory response with cellular infiltration and microbial overgrowth, plasma proteins could be exposed to both proteinases and oxidants released from the granulocytes, as well as to proteinases from the microorganisms. When human complement component C5 was digested by cysteine proteinases (i.e. gingipain-R and gingipain-K) from Porphyromonas gingivalis, limited cleavage of the C5 molecule was observed. If C5 was first oxidized by hydroxyl radicals, these gingipains converted modified C5 to fragments that exhibited significantly greater pro-inflammatory activity than did digests of unmodified C5. After cleavage of oxidized C5 by gingipain-R, the digest exhibited measurably greater neutrophil enzyme release and chemotaxis of human polymorphonuclear leukocytes (PMNs) compared with the activities of unoxidized C5 digests. Gingipain-K generates virtually no polarization or chemotactic activity of human PMNs from C5, nor is enzyme release stimulated by these C5 digests. However, when oxidized C5 was digested by gingipain-K, human PMNs were stimulated for polarization, chemotaxis and enzyme release indicating that an active fragment had been generated. Proteolysis of oxidized C5 evokes greater neutrophil activation than does proteolysis of unoxidized protein, a fact which supports the hypothesis that oxidation and proteolysis may be coupled to enhance the destructive effects of the inflammatory process. These results, in which digests of both oxidized and unmodified complement component C5 were evaluated, support the general concept that oxidation and proteolysis may participate cooperatively in amplifying both the severity and duration of the inflammatory reaction. 相似文献
33.
Abnormal expression of the human CD44 gene in early colorectal malignancy with special reference to variant exon 9 (9v). 总被引:2,自引:0,他引:2 下载免费PDF全文
AIMS: To examine the expression of CD44 variant exon 9 in early colorectal malignancies. METHODS: Formalin fixed, paraffin wax embedded tissue sections from 30 cases of tubular adenoma and 35 cases of adenoma with focal carcinoma of the colon were examined immunohistochemically using a monoclonal antibody (MAb 11.24) directed against CD44-9v. RESULTS: In the normal colorectal mucosa immunoreactivity was confined to the basal part of the crypts and was expressed in less than 10% of crypt cells. CD44-9v was expressed in the superficial part of tubular adenoma with mild atypia in 67% of the cases and in 19% of the tumour cells. The immunoreactivity was observed along the basement membrane in mild atypia, as in the non-neoplastic crypts. In the course of progression to severe atypia the spatial polarity of immunoreactivity was lost, and the extent of CD44-9v expression increased in intensity and in the percentage of positive cases and positive cells. In the carcinomatous lesions of adenoma with focal carcinoma, 94% of the cases and 44% of the tumour cells were positive for CD44-9v protein. CONCLUSION: CD44-9v may be overexpressed at the early stage of colorectal tumorigenesis and this increase continues throughout the course of the disease. 相似文献
34.
Kokubo A Yasuoka Y Nishikitani M Saigenji K Kawahara K 《The Japanese journal of physiology》2005,55(6):317-324
To determine if vasoactive intestinal peptide (VIP) restores neural activity from tetrodotoxin (TTX) blockade, we studied the effects of VIP and related agents on carbachol (Cch)-induced Cl(-) secretion in control-isolated guinea pig distal colon and in that treated with TTX. The short circuit current (I(sc)) increased dose-dependently after serosal applications of Cch (10(-6) - 2 x 10(-5) M) and VIP (5 x 10(-9) - 10(-7) M). But no additive or synergistic increase in I(sc) was observed. Cch- and VIP-induced I(sc) was completely abolished by a serosal application of TTX (10(-6) M). However, a serosal application, not mucosal, of VIP (10(-7) M) and 8-bromo-cAMP (10(-3) M) restored the Cch-stimulated, TTX-inhibited I(sc) by 113% and 75.8%, respectively. Furthermore, mucosal and serosal applications of forskolin (aden late cyclase activator) restored the I(sc) by 43.9% and 65.3%, respectively. The restored I(sc) was completely abolished by atropine (muscarinic receptor antagonist). These results suggest that VIP may restore the cholinergic activity by increasing the level of intracellular cAMP, and that cholinergic neuron is very likely to be responsible for the regulation of Cl(-) secretion at neuroepithelial junctions. The exact mechanism of VIP's effect on the TTX-inhibited epithelial Cl(-) secretion, and its possible usefulness in the treatment of TTX-induced pathophysiological conditions, remain to be determined. 相似文献
35.
Recent progress in molecular and cellular biology has led to the development of numerous effective cardiovascular drugs. However, there are still a number of diseases for which no known effective therapy exists, such as peripheral arterial disease, ischaemic heart disease, restenosis after angioplasty, and vascular bypass graft occlusion. Currently, gene therapy is emerging as a potential strategy for the treatment of cardiovascular disease despite its limitations. The first human trial in gene therapy for cardiovascular disease was started at 1994 to treat peripheral vascular disease using vascular endothelial growth factor (VEGF). Then, many different potent angiogenic growth factors were tested in clinical trials to treat peripheral arterial disease and ischaemic heart disease. Improvement of clinical symptoms in peripheral arterial disease and ischaemic heart disease has been reported. This review focuses on the future potential of gene therapy for the treatment of cardiovascular disease. In the future, gene therapy might become a real pharmacotherapy to treat cardiovascular disease. 相似文献
36.
Ei Kawahara Yoshio Oda Shogo Katsuda Isao Nakanishi Kunihiko Aoyama Katsuro Tomita 《Virchows Archiv : an international journal of pathology》1991,419(5):373-380
Summary Thickened ligamenta flava obtained from 14 patients with spinal canal stenosis were examined with special reference to type VI collagen. The characteristic histological finding in the thickened area was rupture of normal elastic fibre meshwork with resultant fibrosis which usually appeared hyaline. Using an immunohistological method, collagen types VI, I and III were found to be present in the hyaline matrix. Ultrastructural study revealed many microfilamentous structures of type VI collagen admixed in loosely packed, banded collagen fibres. With differential salt precipitation of pepsin-extracted collagen the existence of type VI collagen was confirmed by SDS-polyacrylamide gel electrophoresis analysis and Western blotting analysis using anti-type VI collagen antibody. Quantification of type VI collagen in pepsin-extracted crude collagen samples by an inhibition enzyme-linked immunosorbent assay showed an increasing amount of type VI collagen in the thickened ligamenta flava compared to the normal ligaments. Thus, increase of type VI collagen is the main contribution to the thickening of the ligamentum flavum. This may represent an adaptational and reparative process associated with disruption of elastic fibres. 相似文献
37.
Hiroyoshi Suzuki Miburu Emi Akira Komiya Yoshiyuki Fujiwara Ryuichi Yatani Yusuke Nakamura Jun Shimazaki 《Genes, chromosomes & cancer》1995,13(3):168-174
Human prostate cancers frequently show loss of heterozygosity at loci on the short arm of chromosome 8. In order to take a step toward isolation of the putative tumor suppressor gene(s) on 8p via positional cloning, we performed high-resolution deletion mapping in 46 prostate cancers (stage B, 20 cases; stage C, 8 cases; endocrine therapy-resistant cancer death, 18 cases) using new 12 restriction fragment length polymorphism markers for this chromosomal region. Allelic losses were observed in 25 of the 44 cases (57%) that were informative with at least one locus. Detailed deletion mapping defined a 1.2 Mb commonly deleted region at 8p22-p2 1.3 flanked by markers cMSR-32 and C18- 105 1. A second region of common deletion was identified between C18-1312 and C18-494 at 8p21-8p11.22, suggesting that at least two tumor suppressor genes associated with prostate cancer are present on chromosome arm 8p. Allelic losses on 8p were observed more frequently in the cancer death cases (14/17, 82%) than in early-stage tumors (11/27, 40%; P < 0.01, Fisher's exact test). In two out of 7 patients for whom DNA was available from metastatic cancers as well as from normal tissues and primary tumors, the primary cancer foci had no detectable abnormality of 8p, but the metastatic tumors showed loss of heterozygosity. These results suggest that inactivation of tumor suppressor genes on 8p plays an important role in the progression of prostate cancer. © 1995 Wiley-Liss, Inc. 相似文献
38.
Yajima N Wada R Yamagishi S Mizukami H Itabashi C Yagihashi S 《Human pathology》2005,36(11):1217-1225
Epithelial neoplasms of appendix are infrequent, and their pathological features are not fully characterized. We collected 33 cases of appendiceal tumors and examined immunohistochemically the expression of cytokeratins (CK, CK7, and CK20), mucin core protein (MUC1, MUC2, MUC5AC, and MUC6), E-cadherin, chromogranin A, and p53 protein. Gene analysis of TP53 was also conducted on exons 5 to 8. Clinically, mucinous tumors were predominant in females. Immunohistochemically, all the tumors expressed CK20, whereas CK7 was positive in one third of the cases. Similarly, MUC2 was expressed in all the tumors, whereas MUC1 and MUC5AC were detected in about a half of the cases. Although chromogranin A-positive cells are generally sparse in normal appendix, they were more common in mucinous tumors than in nonmucinous tumors. Contrary to the previous data reported (Mod Pathol 2002;15:599-605), mucinous carcinoma exhibited a higher frequency of p53-positive cells (mean 29%) compared with mucinous adenoma (2.8%) (P < .001), whereas nonmucinous tumors showed high levels of p53-positive cells to similar extent (51%-67%) in both adenoma and carcinoma. The high expression of p53 protein coincided with the presence of mutations in multiple sites of TP53 gene in mucinous tumors. This is the first report that characterized the immunophenotypic profile of appendiceal epithelial neoplasms with an emphasis of a higher frequency of p53 positivity in mucinous carcinoma cases compared with mucinous adenoma in the appendix. 相似文献
39.
40.
Trivalent heat-labile- and heat-stable-enterotoxin probe conjugated with horseradish peroxidase for detection of enterotoxigenic Escherichia coli by hybridization. 总被引:2,自引:0,他引:2 下载免费PDF全文
A Abe K Komase A Bangtrakulnonth O A Ratchtrachenchat K Kawahara H Danbara 《Journal of clinical microbiology》1990,28(12):2616-2620
A 1,268-bp polynucleotide probe for heat-labile and heat-stable enterotoxins (LTh, STIa, STIb) was conjugated with horseradish peroxidase (HRP). The HRP-conjugated trivalent probe was applied to the detection of enterotoxigenic Escherichia coli (ETEC) by colony and stool hybridizations. The binding of the probe to its targets was assayed by the addition of HRP substrates hydrogen peroxide and luminol in the presence of an enhancer, and the chemiluminescence was recorded by exposure to X-ray film. Slot blot hybridization demonstrated that the HRP-conjugated trivalent probe specifically hybridized with the DNA isolated from ETEC strains. The trivalent probe also specifically identified bacterial colonies of ETEC that produced LTh, STIa, STIb, LTh-STIa, or LTh-STIb. Treatment of targets with sodium dodecyl sulfate and proteinase K remarkably reduced nonspecific hybridization to DNAs of non-ETEC strains. Furthermore, this probe was able to detect stool specimens seeded with 10(2) original ETEC cells per 5 mg of feces. These results suggest that the HRP-conjugated trivalent probe is a candidate for use in the clinical laboratory to detect ETEC. 相似文献