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31.
Summary In vivo prostatic secretion was collected from retired breeder Sprague Dawley rats using a method for isolated perfusion of the rat prostatic urethra. Enzymatic acid phosphatase determination was performed on the collected effluent. Control acid phosphatase secretion was 24.2±2.7 nm over 30 minutes. Intravenous phenylephrine 5 mg/kg stimulated a 10 fold increase in acid phosphatase secretion. The secretion seen with phenylephrine was dose dependent and could be blocked with prazosin, but not yohimbine, atropine, or propranolol. Intravenous -adrenergic agonist isoproterenol caused no increase in the secretion of rat prostatic acid phosphatese. Intravenous administration of the cholinergic agonist pilocarpine also resulted in a dose dependent rise in acid phosphatase secretion. The stimulation seen could be blocked by atropine but not phentolamine or propranolol. The stimulation of acid phosphatase secretion seen with 1 adrenergic or cholinergic agonists was not additive. Intravenous vasoactive intestinal peptide did not stimulate acid phosphatase secretion nor did it augment the secretion induced by 1 adrenergic or cholinergic agonists. Release of acid phosphatase into rat prostatic exocrine secretion is under both 1 adrenergic and cholinergic control.Supported by the US Veterans Administration 相似文献
32.
H. Fujiwara M. Emi H. Nagai T. Nishimura N. Konishi Y. Kubota T. Ichikawa S. Takahashi T. Shuin T. Habuchi O. Ogawa K. Inoue M. H. Skolnick J. Swensen N. J. Camp S. V. Tavtigian 《Journal of human genetics》2002,47(12):0641-0648
The recently identified prostate cancer susceptibility gene ELAC2 (HPC2) harbors two common missense variants, a serine to leucine substitution at residue 217 (Leu217) and an alanine to threonine
substitution at residue 541 (Thr541). We genotyped the two variants in a Japanese cohort consisting of 350 prostate cancer
patients 242 male population controls, and 114 male low-risk controls. Both missense alleles, Leu217 and Thr541, were carried
at higher frequency in Japanese patients than in the controls (Leu217, P = 0.0012; Thr541, P = 0.0145), and the odds ratios associated with carrying these sequence variants were higher in Japanese than in Caucasians.
Although the Leu217 and Thr541 variants of ELAC2 are less common in Japanese than in Caucasians, both variants confer significantly increased risk of prostate cancer in Japanese.
Carriage of these variants was not associated with age at diagnosis, tumor stage, or tumor grade in these Japanese prostate
cancer patients. The allele-specific pattern of risk observed in Japanese and familial Caucasian patients was qualitatively
similar; however, the magnitude of that risk was considerably greater in Japanese than in Caucasians.
Received: September 3, 2002 / Accepted: October 2, 2002 相似文献
33.
14只日本大耳白雄兔,7只为假手术组(SOG),7只为输精管结扎组(VG)。16个月后,检测前列腺睾酮受体和血清睾酮的变化。结果是VG和SOG胞液受体的kd值分别为10.21nM和3.42nM,最大结合容量分别为33.68fmol/mgpro.和10.42fmol/mg pro;胞核受体的kd值分别为9.36nM和4.81nM,最大结合容量分别为440.90fmol/mg DNA和203.66fmol/mg DNA。单点分析的结果是VG和SOG胞液受体浓度分别为26.13±5.64和8.40±1.66fmol/mg pro,VG明显高于SOG(P<0.01);胞核受体浓度分别为239.95±66.37和204.89±65.12fmol/mg DNA,两组比较无差异(P>0.05)。血清睾酮两组比较无统计学意义,并与胞液、胞核受体浓度无相关关系。 相似文献
34.
McCarty MF Bielenberg D Donawho C Bucana CD Fidler IJ 《Clinical & experimental metastasis》2002,19(7):609-615
Primary tumor growth and metastasis depend on angiogenesis, which is determined by the balance between proangiogenic and antiangiogenic
molecules. Interferon (IFN)-α and -β inhibit angiogenesis through downregulation of interleukin-8, matrix metalloproteinase-9,
and basic fibroblast growth factor. To provide evidence for the causal role of IFN-α/β in the induction of neoplasms, their
angiogenesis, and hence, progressive growth, we carried out experiments using 129S6 IFN-α/β receptor −/− mice back-crossed
to BALB/c nude mice. Subcutaneous angiogenesis was determined following implantation of gelfoam sponges containing 0.4% agarose
and several proangiogenic molecules. Tumorigenicity and production of lung metastasis were determined subsequent to subcutaneous
and intravenous injections, respectively, of highly metastatic A375SM human melanoma cells. Carcinogenesis was induced by
chronic exposure of mice to UVB radiation (5 kJ/m2, 3 times/week). Angiogenesis, tumorigenicity, and production of metastasis, as well as development of autochthonous skin
tumors, were all accelerated in IFN-α/β receptor −/− mice as compared to control mice. Collectively, the data show that inability
to respond to endogenous IFN-α/β (through a mutation in the IFN-α/β receptor) leads to increased susceptibility to carcinogenesis,
enhanced angiogenesis, tumorigenicity, and metastasis.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
35.
Yamasaki M Takeshima Y Fujii S Kitaguchi S Matsuura M Tagawa K Inai K 《Pathology international》2000,50(10):778-785
Bronchiolo-alveolar carcinoma (BAC) is a type of lung adenocarcinoma characterized by growth along the alveolar wall. It is divided into two subtypes: sclerosing BAC (SBAC), which has central fibrosis, and non-sclerosing BAC (NSBAC), which lacks central fibrosis. We compared the genetic alterations in these two types of BAC with those in atypical adenomatous hyperplasia (AAH). There were 39 cases of SBAC, 19 of NSBAC and 20 of AAH. To detect the loss of heterozygosity (LOH) we used the microsatellite markers D3S1234 and D3S1300 on chromosome 3p, IFNA and D9S144 on 9p, and TP53 on 17p. We also used polymerase chain reaction-SSCP analysis and direct sequencing to examine a point mutation of the p53 gene at exons 5-8. At the TP53 locus, the frequencies of LOH showed a statistical rank-difference correlation among AAH, NSBAC and SBAC. On chromosomes 3p and 9p there were no statistical differences of LOH among AAH, NSBAC and SBAC. We detected a significant statistical rank-difference correlation in the p53 mutation among AAH, NSBAC and SBAC. These findings suggest that a process of multistep carcinogenesis from AAH through NSBAC to SBAC might occur in some cases of adenocarcinoma, and LOH of 3p and 9p might be an early event of carcinogenesis, while the p53 mutation might be a later event. 相似文献
36.
Kazuhiko Orikasa Shin-ichi Fukushige Senji Hoshi Seiichi Orikasa Keiichi Kondo Yasuhide Miyoshi Yoshinobu Kubota A. Horii 《Journal of human genetics》1998,43(4):228-230
Prostate cancer is a major cause of cancer death among elderly men in America, Europe, and Japan. However, the molecular
mechanism of carcinogenesis is not yet well characterized. Frequent loss of heterozygosity (LOH) on chromosome 10q was reported
in prostate cancer, and a candidate tumor suppressor gene, PTEN, was isolated on chromosome band 10q23.3. To investigate the genetic alterations of PTEN, we examined 45 primary prostate cancer specimens. LOH at the PTEN locus was observed in two (11.1%) of 18 tumors. However, no mutations were observed in any of the primary prostate cancers.
These data suggest that mutation of the PTEN gene does not play a major role in prostate carcinogenesis of Japanese patients.
Received: February 6, 1998 / Accepted: July, 3, 1998 相似文献
37.
Reddy MV Storer RD Laws GM Armstrong MJ Barnum JE Gara JP McKnight CG Skopek TR Sina JF DeLuca JG Galloway SM 《Environmental and molecular mutagenesis》2002,40(1):1-17
3-Methylindole (3MI), melatonin (Mel), serotonin (Ser), and tryptamine (Tryp) were evaluated in vitro for their potential to induce DNA adducts, DNA strand breaks, chromosomal aberrations (Abs), inhibition of DNA synthesis, and mutations. All compounds produced DNA adducts in calf thymus DNA in the presence of rat liver S9. In cultured rat hepatocytes, all produced DNA adducts but none induced DNA strand breaks. In Chinese hamster ovary cells, 3MI and Mel produced DNA adducts, Abs, and inhibition of DNA synthesis with and without S9, except that Mel without S9 did not form adducts. Ser formed DNA adducts, was an equivocal Abs inducer, and suppressed DNA synthesis. Tryp induced neither adducts nor Abs, but did suppress DNA synthesis with S9. Ser and Tryp were less cytotoxic than 3MI and Mel. Mel, Ser, and Tryp failed to induce mutations in Salmonella and E. coli strains with or without S9. 3MI and Mel produced DNA adducts but not mutations in Salmonella TA100 with S9. 3MI and its metabolite indole 3-carbinol also did not induce mutations in a shuttle vector system in human cells. The lack of correlation between DNA adducts and other genotoxicity endpoints for these indole compounds may be due to the higher sensitivity of the (32)P-postlabeling adduct assay or it may indicate that the indole-DNA adducts per se are not mutagenic and are not able to induce strand breaks or alkali-labile lesions. The indole-induced Abs may result from cytotoxicity and suppression of DNA synthesis with minimal if any contribution from DNA adducts. 相似文献
38.
Ryoichi Sakamoto Tetsuya Nitta Yoshiaki Kamikawa Kazumasa Sugihara Kazuhisa Hasui Shinichiro Tsuyama Fusayoshi Murata 《Medical Electron Microscopy》2004,37(1):52-61
The aim of this study was to investigate cell kinetics and ultrastructural changes during carcinogenesis using a hamster 9,10-dimethyl-1,2-benzanthracene (DMBA)-induced tongue cancer model. Five squamous cell carcinomas, five dysplastic epithelia, seven hyperplastic epithelia, and four normal epithelia were obtained from 21 hamster tongues by applying 1.0% acetone solution of DMBA on the left lingual mucosa after scratching with a root canal broach. Ultrastructural examination revealed that the number of microvilli increased, whereas that of desmosomes decreased during carcinogenesis. Cell proliferation was analyzed by means of 5-bromodeoxyuridine (BrdU) immunohistochemistry and in situ hybridization (ISH) for histone H3 mRNA. The BrdU and histone H3 mRNA labeling indices (LIs) were lowest for normal epithelium, higher for hyperplastic and dysplastic epithelia, and highest for squamous cell carcinoma. Cytoplasmic histone H3 mRNA and nuclear BrdU were localized in virtually identical areas of serial sections. The correlation coefficient for the relationship between these two LIs was 0.97 (P 0.001). These results suggest that the assessment of cell proliferation using H3 mRNA ISH will be a useful technique for investigating biological behavior during carcinogenesis. 相似文献
39.
Peter N. Brawn Charles F. Johnson III 《Virchows Archiv : an international journal of pathology》1987,411(5):399-402
Summary Consecutive staging lymphadenectomies on 1046 patients with prostate carcinoma identified 275 patients with metastases in a total of 1115 regional lymph nodes. No prostate carcinomas composed entirely of single malignant glands metastasized and no patient had metastases composed entirely of single malignant glands. All prostate carcinomas that metastasized had cribriform and/or undifferentiated histological patterns in the prostate and in the metastases. These findings suggest that identification of cribriform and/or undifferentiated histological patterns, through rebiopsy or further examination of the surgical specimen, should be considered prior to subjecting patients with prostate carcinomas composed entirely of single malignant glands to therapy or procedures directed against the possibility of metastatic disease. 相似文献
40.
Most models suggest that the cell of origin of papillary carcinoma is the mature thyroid follicular epithelial cell. In a recent study, p63 was detected in papillary carcinoma, Hashimoto's thyroiditis, and in squamoid aggregates and solid cell nests (SCNs), embryonic remnants found sporadically in the fully developed thyroid. In the present study, the relationship between solid cell nests and papillary carcinoma was investigated further. Four-micrometer sections from 88 routinely fixed and processed archival thyroidectomy specimens were pretreated with citric acid pH 6.0 for antigen retrieval, then incubated overnight with anti-p63 monoclonal antibody 4A4. Slides were stained with a streptavidin-biotin kit and diaminobenzidine as chromogen and were counterstained with hematoxylin. Squamoid aggregates or SCNs were noted in 21 specimens. Several morphologic variants of SCNs were found, all of which displayed p63 positivity. These included undifferentiated SCNs and those displaying commitment toward squamoid and ciliated glandular differentiation. Small, morphologically inconspicuous aggregates of p63-positive cells were commonly found in Hashimoto's thyroiditis. Commitment of p63-positive undifferentiated cells toward thyroid follicular epithelial differentiation was occasionally noted. One SCN variant, also associated with Hashimoto's thyroiditis, was a floretlike arrangement of p63-positive cells with fusiform nuclei. p63 staining was strong and uniform in some SCNs, but in other SCNs it was compartmentalized and homologous to stem cell-staining patterns in normal squamous or bronchial epithelia. Stem cell-like staining, associated with compartmentalized p63 staining or p63-positive undifferentiated cells, was noted in 7 of 27 papillary carcinomas. p63 immunostaining is a highly sensitive means of detecting SCNs. p63 expression patterns in SCNs and a subset of papillary carcinomas are closely homologous to stem cell-associated p63 staining patterns that have been described elsewhere in squamous and bronchial epithelia. We propose a stem-cell-associated model of papillary carcinoma oncogenesis that suggests that (1) p63-positive embryonal remnants rather than mature follicular cells are the cells of origin of a subset of papillary carcinomas; (2) these p63-positive cells are pluripotent and may stay undifferentiated or undergo benign squamoid or glandular maturation, may undergo thyroid follicular epithelial differentiation, may undergo oncogenic change leading to papillary carcinoma, or may trigger an immune reaction, resulting in lymphoid infiltration and Hashimoto's thyroiditis; and (3) Hashimoto's thyroiditis and papillary carcinoma may therefore be linked etiologically, because both disorders may be initiated by the same population of pluripotent p63-positive embryonal stem cell remnants. 相似文献