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71.
Irinotecan Hydrochloride (CPT-11) and 7-ethyl-10-hydroxycamptothecin (SN-38), which are both topoisomerase I inhibitors with potent antitumor effects in vivo and in vitro, were tested for the induction of programmed cell death (PCD) in leukemia/lymphoma cell lines. When the human T-cell leukemia cell line HUT-102 and the human promyelocytic leukemia cell line HL-60 cells were exposed to CPT-11, PCD characterized by a DNA fragmentation ladder of 180-200 bp in agarose gel electrophoresis and loss of cell viability was induced. The PCD inducing activity of SN-38, an active metabolite of CPT-11, was much more powerful than that of CPT-11. Besides inducing PCD in HUT-102 and HL-60 cells, SN-38 also induced PCD in the human erythroblast leukemia cell line K-562, which was resistant to CPT-11. Induction of PCD by SN-38 and CPT-11 was dose- and time-dependent. PCD in HUT-102 cells induced by SN-38 was prevented neither by aurintricarboxylic acid (ATA), an endonuclease inhibitor, as determine by DNA electrophoretic profiles and the number of viable cells, nor by the protein kinase C (PKC) activator phorbol 12-myristate 13-acetate (PMA). The present data suggest that the topoisomerase I inhibitors, SN-38 and CPT-11 exert antitumor activity through induction of PCD in involved cells, at least in part. The PCD-inducing activity of the topoisomerase II inhibitor VP-16 was also tested in the above three cell lines and compared with CPT-11 and SN-38. 相似文献
72.
B Lindmark H Kamiguchi M Tsuda M Yamamura 《The Tokai journal of experimental and clinical medicine》1990,15(4):347-351
In an attempt to find a molecular marker for the putative abnormal allele in heterozygous alpha 1-antichymotrypsin (ACT) deficiency (a rare trait associated with early emphysema, childhood asthma and chronic "cryptogenic" liver disease) the isoelectric focusing pattern of neuraminidase treated plasma samples from subjects of ACT deficiency families as well as acute phase plasma were compared. There was no difference in the isoform pattern of plasma from ACT deficiency heterozygotes, normal subjects or patients with acute phase response. However, in acute phase plasma there was a disproportional increase in two isoforms, one of which conceivably may be used to mark the early phase of the acute phase response. 相似文献
73.
Sakuragi T Fujiwara K Akashi-Tanaka S Tsuda H Fukutomi T 《Breast cancer (Tokyo, Japan)》1997,4(1):53-56
Dermatofibrosarcoma protuberans (DFSP) is a slow-growing but locally aggressive, fibrous tumor that has a high rate of local
recurrence after surgical resection. This tumor occurs most commonly in the trunk and proximal extremities. In this report
we present a case of dermatofibrosarcoma protuberans in the skin over the breast which was re-excised after pathological diagnosis,
considering cosmetic aspects. Only three other cases of dermatofibrosarcoma protuberans of the anterior chest wall have been
encountered in our hospital, and all of these cases were male. The presence of this tumor in the skin over the breast appears
to be rare in females. Careful complete resection is recommended for this type of tumor. 相似文献
74.
Despite the progress in virological and molecular studies on human T-cell leukaemia virus (HTLV-1), there still exist enigmas in biological and clinical features of adult T-cell leukaemia/lymphoma (ATL). They include the way of the development of ATL clones, the role of interleukin-2 (IL-2) receptors on the tumour cells and spontaneous fluctuation of the clinical activity frequently observed in chronic type of the disease. To elucidate these enigmas, based on our recent experimental data, we would like to present a model of the development of ATL clones from: the view point of programmed cell death (PCD) and its control. 相似文献
75.
Nakamura A Kojima S Isama K Umemura T Kawasaki Y Takada K Tsuda M Kurokawa Y 《Journal of long-term effects of medical implants》1995,5(4):263-273
Three polyurethane materials were prepared by removing and adding the leachable oligomers from and to the same polyetherurethane (PEU). The three PEU materials were dissolved in tetrahydrofuran (THF) and dimethyformamide (DMF) and the solutions were cast on a glass plate to make films of smooth and foamed surfaces, respectively. These six materials and polydimethylsioxane (silicone) were implanted into subcutaneous pocket of rats for 2 years to evaluate the long-term effects around the implant. Among the smooth surface implants, PEU materials induced a higher incidence of tissue responses, including tumor formation than silicone. However, no relationship between the oligomer content and the tissue responses was found. Changing surface morphology from a smooth to a foamed one prolonged the latent period of tumor development and decreased the total tumor incidence. 相似文献
76.
Measuring the hepatic extraction fraction (HEF) of a hepatobiliary radiopharmaceutical helps to differentiate hepatocyte from biliary tract diseases, and it is generally performed using deconvolution analysis. In this study, we measured HEF using spectral analysis. With spectral analysis, HEF was calculated from (the sum of the spectral data obtained by spectral analysis--the highest frequency component of the spectrum) divided by (the sum of the spectral data) x 100 (%). We applied this method to dynamic liver scintigraphic data obtained from six healthy volunteers and from 46 patients with various liver diseases, using 99Tcm-N-pyridoxyl-5-methyltryptophan (PMT). We also measured HEF using deconvolution analysis, in which the modified Fourier transform technique was employed. The HEF values obtained by spectral analysis correlated closely with those obtained by deconvolution analysis (r = 0.925), suggesting our method is valid. The HEF values obtained by spectral analysis decreased as the severity of liver disease progressed. The values were 100.0 +/- 0.0%, 94.7 +/- 13.6%, 76.2 +/- 27.4%, 45.7 +/- 15.6%, 82.7 +/- 24.2% and 95.2 +/- 11.8% (mean +/- S.D.) for the normal controls (n = 6), mild liver cirrhosis (n = 16), moderate liver cirrhosis (n = 11), severe liver cirrhosis (n = 5), acute hepatitis (n = 8) and chronic hepatitis groups (n = 6), respectively. The HEF was obtained more simply and rapidly by spectral analysis than by deconvolution analysis. The results suggest that our method using spectral analysis can be used as an alternative to the conventional procedure using deconvolution analysis for measuring HEF. 相似文献
77.
Shigemi J Mino Y Tsuda T 《Journal of epidemiology / Japan Epidemiological Association》1999,9(5):320-326
Although smoking has been considered a risk factor in causing pepticulcers, no study has examined the effects of job stress on the relationship between peptic ulcers and smoking. To establish a link between gastric or duodenal ulcers over two years and a state of perceived job stress, a questionnaire, including questions on demographics, smoking, history of peptic ulcer and perceived job stress was conducted. Follow-up surveys were carried out every six months to accumulate the data for this analysis and the time span of this follow up study was two years. To examine the role of perceived job stress on the relationship between smoking and peptic ulcers, stratified analyses were performed. Some specific causes of perceived job stress such as "Too much competition," "Schedule is too tight or pressed to work too hard" had high estimated relative risks: 2.13 with 95% confidence interval (CI) of 1.09-4.16 and 2.50 with 95% CI of 0.98-6.40, respectively. Stratified analyses suggested an effect-measure modification of perceived job stress in the relationship between peptic ulcers and smoking. Multiplicative and additive models suggest positive interaction between perceived job stress and smoking. These results suggest that specific perceived job stress is an effect modifier in the relationship between the history of the peptic ulcer and smoking. 相似文献
78.
1. The aim of the present study is to characterize the role of the P2X receptor in spinal nociceptive processing in vivo. We investigated the mechanisms of the P2X receptor agonist alpha,beta-methylene ATP (alpha,betameATP)-induced modulation of acute nociceptive signalling in mouse spinal cord. 2. Intrathecal administration of alpha,betameATP produced a significant and dose-dependent thermal hyperalgesic response. This response was completely blocked by intrathecal pretreatment with the non-selective P2 receptor antagonist, pyridoxal-phosphate-6-azophenyl-2',4'-disulphonate (PPADS) and the selective P2X1, P2X3 and P2X2-3 receptor antagonist, 2',3'-O-(2,4,6-trinitrophenyl)adenosine 5'-triphosphate (TNP-ATP). Pretreatment with alpha,betameATP 15, 30 and 60 min prior to administration of a second dose of alpha,betameATP diminished the alpha,betameATP-induced thermal hyperalgesia. 3. A potent agonist for the P2X1 receptor, beta,gamma-methylene-L-ATP, did not show the hyperalgesic response, indicating that the P2X1 receptor is not involved in the spinal nociceptive pathway. 4. In fura-2 experiments using mouse dorsal root ganglion (DRG) neurons, alpha,betameATP (100 microM) increased intracellular Ca2+ ([Ca2+]i). This was not produced by a second application of alpha,betameATP. The same DRG neurons also showed a marked [Ca2+]i increase in response to capsaicin (3 microM). 5. Intrathecal pretreatment with the Ca2+-dependent exocytosis inhibitor, botulinum neurotoxin B, abolished the thermal hyperalgesia by alpha,betameATP. Furthermore, thermal hyperalgesia was significantly inhibited by the N-methyl-D-aspartate (NMDA) receptor antagonists, 2-amino-5-phosphonopentanoate (APV), dizocilpine and ifenprodil. 6. These findings suggest that alpha,betameATP-induced thermal hyperalgesia may be mediated by the spinal P2X3 receptor subtype that causes unresponsiveness by repetitive agonist applications, and that alpha,betameATP (perhaps through P2X3 receptors) may evoke spinal glutamate release which, in turn, leads to the generation of thermal hyperalgesia via activation of NMDA receptors. 相似文献
79.
Tsuda Hiroyuki; Sakata Takao; Tamano Seiko; Okumara Masanao; Ito Nobuyuki 《Carcinogenesis》1983,4(5):523-528
Sequential observations were carried out on the induction ofpreneoplastic lesions in the liver and the kidney. Rats wereinitially given N-ethyl-N-hydroxyethylnitrosamine (EHEN) intheir drinking water (0.1%) for 3 days (Group 1), 1 week (Group2) or 2 weeks (Group 3) or tap water (Group 4). Rats in Groups1 3 were subjected to partial hepatectomy and unilateralnephrectomy (right side) 2 weeks after the end of EHEN treatment.Rats from these groups were killed in week 10, 20, 30 and 40of the experiment. In the liver, the effect of EHEN in the inductionof -glutamyltranspeptidase (-GT) positive foci and hyperplasticnodules (HN) was clearly dependent on the length of treatment.The preneoplastic lesions increased with the lapse of observationtime. Changes measured as number of -GT positive foci were 1040times greater than those measured as HN, especially among thesmall size range. Values for changes in Group 1 given 0.1% EHENfor 3 days were very low, indicating that this dose is closeto the threshold. Two rats with hepatocellular carcinoma inGroup 3 given EHEN for 2 weeks survived until week 40. In thekidney, tubular epithelial proliferations composed of cellswith slightly basophilic cytoplasm and slightly atypical nucleiwere tentatively named atypical cell foci (ACF). EHEN inducedACF, renal cell adenomas and renal cell carcinomas. The increasein the induction of ACF was dependent on the length of observationperiod but not on the length of treatment. Even though controlrats (not treated with EHEN) also had ACF, their quantitativevalues were far less than the groups given EHEN and killed atweek 40, indicating that a large number of ACF were inducedby EHEN. Therefore, EHEN is good for experimental inductionof preneoplastic lesions in the liver and kidney of rats. Theexperimental schedule for Groups 1 and 2 could be used as ashort-term screening test for promoters and the schedule forGroup 3 as an assay for inhibitors. 相似文献
80.
High incidence of p53 gene mutation in human ovarian cancer and its association with nuclear accumulation of p53 protein and tumor DNA aneuploidy. 总被引:10,自引:0,他引:10
T Kihana H Tsuda S Teshima S Okada S Matsuura S Hirohashi 《Japanese journal of cancer research》1992,83(9):978-984
Using the polymerase chain reaction and single-strand conformation polymorphism analysis, p53 gene mutations were examined in 24 cases of ovarian tumor including 14 ovarian carcinomas and 2 borderline cases of common epithelial type, 7 germ cell tumors, and one stromal tumor. Abnormal bands indicating mutations were detected in 12 (50%) of the cases examined, being present most frequently in common "epithelial" ovarian carcinoma (71%, 10/14). One case each of squamous cell carcinoma originating in a dermoid cyst and anaplastic dysgerminoma were positive for mutation. Direct sequencing confirmed 12 mutations and revealed G-->A and G-->C nucleotide changes in 5 and 3 cases (42% and 25%), respectively. The mutation was localized at the CpG site of the gene in 3 cases. Immunohistochemical examination of p53 protein in 21 cases and DNA flow-cytometrical analysis in 17 cases were also performed. Nuclear accumulation of the p53 protein and DNA aneuploidy pattern were detected in 11 (52%) and 9 (53%) cases, respectively. These were significantly correlated with p53 gene mutation (P < 0.01 and P < 0.05, respectively; Fisher's exact test). Neither mutation of the p53 gene, nuclear accumulation of p53 protein nor DNA aneuploidy was detected in borderline cases of common "epithelial" type, typical dysgerminoma and immature teratoma. These results suggest that p53 gene mutation, nuclear accumulation of the protein and the DNA aneuploidy pattern are events occurring almost simultaneously in the progression of ovarian tumors, and that p53 abnormalities seem to be correlated with a high grade of malignancy. 相似文献