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141.
The prevalence of TT virus (TTV) infection and its relationship to hepatitis in children 总被引:4,自引:0,他引:4
Iriyama M Kimura H Nishikawa K Yoshioka K Wakita T Nishimura N Shibata M Ozaki T Morishima T 《Medical microbiology and immunology》1999,188(2):83-89
TT virus (TTV) is a newly discovered virus from a patient with post-transfusion hepatitis. We investigated the frequency
and pathogenesis of TTV infection in children. A semi-nested PCR assay was used to amplify TTV-DNA in serum samples from 254
ambulatory children without liver disease, 20 with hepatitis of unknown etiology, and 18 transfusion recipients or hemophiliacs.
In positive samples, TTV-DNA was quantified by real-time quantitative PCR using a fluorescent probe. We detected TTV-DNA in
20% of children with hepatitis of unknown etiology, which was not statistically different from the 23% prevalence in ambulatory
children. In transfusion recipients or hemophiliacs, the frequency was higher (50%) than that in ambulatory children (P = 0.01). Among ambulatory children, TTV-DNA was frequently detected in children with acute gastroenteritis (36%). TTV-DNA
was detected in 10% of the infants under 6 months old, and 20% of the children from 7 to 12 months old. The prevalence was
constant after the age of 1 year; however, the copy number of TTV-DNA was significantly higher in children under 1 year of
age (mean: 105.4 versus 103.8 copies/ml, P= 0.008). Finally, TTV-DNA was quantified serially in three children with chronic hepatitis who were positive for TTV-DNA.
The presence or amount of TTV-DNA was unrelated to the serum alanine aminotransferase level. These results indicate that TTV
infection is common in children. The larger quantity of TTV-DNA in infants and the high prevalence of TTV in children of all
ages suggest that TTV may be transmitted in early childhood. Its relationship to hepatitis is doubtful in children.
Received: 8 April 1999 相似文献
142.
Echocardiographically documented mitral-valve prolapse. Long-term follow-up of 237 patients 总被引:5,自引:0,他引:5
R A Nishimura M D McGoon C Shub F A Miller D M Ilstrup A J Tajik 《The New England journal of medicine》1985,313(21):1305-1309
We determined the long-term prognosis for patients with mitral-valve prolapse documented by echocardiography by following 237 minimally symptomatic or asymptomatic patients for a mean of 6.2 years (range, 1 to 10.4). The actuarial eight-year probability of survival was 88 per cent, which is not significantly different from that for a matched control population. An initial left ventricular diastolic dimension exceeding 60 mm was the best echocardiographic predictor of the subsequent need for mitral-valve replacement (17 patients). Of the 97 patients with redundant mitral-valve leaflets identified echocardiographically, 10 (10.3 per cent) had sudden death, infective endocarditis, or a cerebral embolic event; in contrast, of the 140 patients with nonredundant valves, only 1 (0.7 per cent) had such complications (P less than 0.001). Most patients with echocardiographic evidence of mitral-valve prolapse have a benign course, but subsets at high risk for the development of progressive mitral regurgitation, sudden death, cerebral embolic events, or infective endocarditis can be identified by echocardiography. 相似文献
143.
Genetic control of nonresponsiveness to hepatitis B virus vaccine by an extended HLA haplotype. 总被引:6,自引:0,他引:6
K Hatae A Kimura R Okubo H Watanabe H A Erlich K Ueda Y Nishimura T Sasazuki 《European journal of immunology》1992,22(7):1899-1905
We previously reported evidence for a statistical association between the serologically determined HLA-Bw54, DR4 and DRw53 alleles and the non-immune responsiveness to hepatitis B virus surface antigen (HBsAg) in the Japanese population. To identify the locus and allele within the HLA region associated with the nonresponsiveness to HBsAg, serological HLA typing, DNA typing of HLA-DQ and DP alleles using amplified HLA genes and sequence-specific oligonucleotide probes, and restriction fragment length polymorphism (RFLP) analysis of the fourth component of complement (C4) genes were performed in healthy unrelated Japanese vaccinees who were immunized subcutaneously three times with plasma-derived HBsAg vaccine. In nonresponders to HBsAg, the frequencies of HLA-Bw54 cross-reactive epitope group (CREG); (Bw54, Bw55, Bw56 and other Bw22), C4 RFLP (6.5 kb + 12.0 kb), DR4, DRw53 and DQw4 (DQA1*0301-DQB1*0401) were increased and the frequencies of HLA-DR1, DRw6 and DQw1 were decreased as compared with those in healthy unrelated controls. Further analysis revealed that the coexistence of HLA-Bw54CREG and DR4-DRw53-DQw4 (DQA1*0301-DQB1*0401) was associated with the nonresponder group, whereas, donors positive for exclusively either Bw54 CREG or DR4-DRw53-DQw4 (DQA1*0301-DQB1*0401) were not associated with the nonresponder group. Because there is a strong linkage disequilibrium between HLA-Bw54CREG, C4 RFLP (6.5 kb + 12.0 kb) and HLA-DR4-DRw53-DQw4 (DQA1*0301-DQB1*0401) in the Japanese population, the extended HLA-Bw54CREG-C4 RFLP (6.5 kb + 12.0 kb)-DR4-DR-w53-DQw4 (DQA1*0301-DQB1*0401) haplotype may well control nonimmune responsiveness to HBsAg. This extended HLA haplotype controls nonresponsiveness as a dominant genetic trait because all ten heterozygotes and two of three probable homozygotes of this extended HLA haplotype were nonresponders. 相似文献
144.
Association between HLA and Japanese patients with rheumatoid arthritis 总被引:12,自引:0,他引:12
N Ohta Y K Nishimura K Tanimoto Y Horiuchi C Abe Y Shiokawa T Abe M Katagiri T Yoshiki T Sasazuki 《Human immunology》1982,5(2):123-132
Japanese patients with rheumatoid arthritis (RA) were observed to have a statistical association with HLA-DR4, MT3. Strong association between the clinical severity of RA and HLA was also observed. Male patients had a stronger association with HLA than female patients. Males are more resistant to RA than females. This suggested that the threshold of liability for RA is higher in males than in females. Japanese patients with RA with systemic vasculitis were negative for HLA-Bw44 and had antilymphocytotoxic autoantibody, indicating that RA with systemic vasculitis is different in etiology from RA without systemic vasculitis. 相似文献
145.
Nishimura N Nishioka Y Shinohara T Ogawa H Yamamoto S Tani K Sone S 《Journal of immunological methods》2001,253(1-2):113-124
Dendritic cells (DC) are professional antigen-presenting cells in the immune system. Gene transduction of DC with tumor-associated antigen (TAA) or other genes that enhance the immune reaction has been considered theoretically useful for DC-based immunotherapy. However, gene transduction of DC generated from human peripheral blood monocytes has been difficult due to its low efficiency, even when adenoviral vector was used at high multiplicity of infection (MOI). In the present study, we examined the effect of centrifugal force to enhance efficiency of adenovirus-mediated gene transduction into human monocyte-derived DC at various rotor speeds at various temperatures for various times. We judged the transduction efficiency using enhanced green fluorescence protein (EGFP)-expressing adenoviral vector, and the best condition for centrifugal transduction was determined as 2000 x g at 37 degrees C for 2 h at an MOI of 10 or greater. At an MOI of 50 without centrifugation, the gene transduction efficiency was about 66% and mean fluorescence intensity (MFI) of EGFP expression was about 150 (at 37 degrees C for 2 h). With centrifugal transduction (2000 x g at an MOI of 50 at 37 degrees C for 2 h), 86% or more DC were gene-modified, and especially, MFI of EGFP expression was highly enhanced (MFI: about 3100 or greater). Centrifugally gene-transduced DC were not damaged and were thoroughly functional as measured by mixed lymphocyte reaction (MLR). The centrifugal method was also applicable to human monocytes and K562 cells. The centrifugal transduction method with adenoviral vector might be helpful for the generation of gene-modified DC. 相似文献
146.
Alteration of cell cycle regulators correlates with survival in epithelial ovarian cancer patients 总被引:7,自引:0,他引:7
The p16-cyclinD1/CDK4-pRb pathway (RB pathway) and p14ARF-MDM2-p53 pathway (p53 pathway) work at the G1-S checkpoint, and the ATM-chk2-CDC25-cyclinB1/cdk1 pathway works at the G2-M checkpoint. The disruption of these pathways is thought to be related to the prognosis of human cancer. In this study, we analyzed the status of these pathways in 107 epithelial ovarian cancer (EOC) patients by immunohistochemistry and evaluated the relationship of these results with chemotherapy response and the prognosis. Altered RB, p53, and G2 pathways were detected in 50.5% (54/107), 51.4% (55/107), and 33.6% (36/107) of cases, respectively. The overall survival (OS) of 77.3% for patients with a normal RB pathway was significantly higher than the OS of 50.0% for patients with an altered RB pathway (by Kaplan-Meier analysis, P = 0.0021). The OS of 66.2% for patients with a normal G2 pathway was significantly higher than the OS of 58.3% for patients with an altered G2 pathway (P = 0.0416). However, the status of the p53 pathway was not related to OS. By univariate and multivariate analyses, advanced stage, high histological grade, altered RB pathway, and altered G2 pathway were significant predictors of poor OS. However, there was no significant relationship between pathway status and chemotherapy response. The status of the RB pathway and of the G2 pathway were independent prognostic factors of EOC. 相似文献
147.
Motonobu Nishimura MD Takashi Nishimura MD Masayuki Ishikawa MD Ayumu Masuoka MD Nobuyuki Okamura MD Keiko Abe MD Takahiro Matsuoka MD Mika Iwazaki MD Kazuhito Imanaka MD Haruhiko Asano MD Shunei Kyo MD 《Journal of artificial organs》2006,9(4):209-213
The presence of a significant organ dysfunction does not immediately exclude patients from consideration for treatment with
a left ventricular assist system (LVAS). However, in treating morbid circulatory shock patients with multiple organ failure,
it is important to know the preoperative and postoperative factor or factors related to the recovery of the damaged organ
function. In this study, we retrospectively analyzed patients receiving a LVAS at our institution and tried to determine the
important factors related to the survival of patients with multisystem failure. Twenty-seven patients who underwent LVAS placement
at Saitama Medical School Hospital between 1993 and 2003 were included in this study. The preoperative risk factors analyzed
were renal dysfunction, respiratory dysfunction, hepatic dysfunction, the existence of active infection, and the combination
of all four factors. As a postoperative factor, the pump flow index (mean LVAS pump flow during the first 2 weeks after LVAS
surgery divided by the body surface area) was analyzed. None of the analyzed preoperative factors could predict survival after
LVAS surgery, but a pump flow index of less than 2.5 l/min/m2 had a significant relationship with death after LVAS surgery. Further analysis revealed that all the patients with a pump
flow index of 3.0 l/min/m2 or more could overcome preoperative organ dysfunction. Congestive heart failure patients with multisystem failure need luxury
pump flow for successful LVAS surgery; this factor could be especially important in device selection and postoperative management. 相似文献
148.
Hitoshi Nishimura Masashi Emoto Kenji Hiromatsu Shunsuke Yamamoto Keiko Matsuura Hiroshi Gomi Toshio Ikeda Shigeyoshi Itohara Yasunobu Yoshikai 《European journal of immunology》1995,25(5):1465-1468
The secretion of tumor necrosis factor (TNF)-α from macrophages is regulated by both priming and triggering signals. We found that macrophages from mice lacking γδ T cells [T cell receptor (TCR) δ?/- mice], which lack the gene encoding the δ chain, produced only small amounts of TNF-α in response to lipopolysaccharide (LPS) and showed a reduced level of expression of CD14. Pre-incubation of macrophages from TCR δ-/- mice with γδ T cells from their TCR δ+/- littermates restored their capacity to produce TNF-α in response to LPS. The priming activity of γδ T cells was in part inhibited by neutralizing anti-interferon (IFN)-γ monoclonal antibodies. Collectively, these results suggest that γδ T cells play a role in priming macrophages to a steady state of activation via IFN-γ secretion, which allows them to produce TNF-α when exposed to LPS. 相似文献
149.
T Nishimura K Tabuki T Takashima M Takagi 《The Japanese journal of antibiotics》1985,38(10):2925-2931
A bacteriological and clinical study of ceftizoxime suppositories (CZX-S) let to the following results. The CZX serum concentration 10 minutes after insertion of one 250 mg suppository (i.e. 5.7-15.2 mg CZX per kg body weight) ranged from 1.64 to 6.53 micrograms/ml (average: 4.41 micrograms/ml). In one child the concentration 7 minutes after insertion was 4.13 micrograms/ml. Therapeutic responsiveness was recorded as "effective" in 8 (88.9%) of the 9 children who were broken down into 6 with tonsillitis, 1 with pharyngitis, and 2 with UTI. Bacteriological studies conducted in 5 children have confirmed eradication in 4 children, one of whom showing appearance of another strain. The rate of discharge of the suppository within 10 minutes after insertion was 20.4%. Reddening and erosion of the anus were observed in 1 child. 相似文献
150.
M Hara T Nishimura S Ohba S Kanamori M Akimoto M Moriyama 《Hinyokika kiyo. Acta urologica Japonica》1985,31(5):845-848
A 65-year-old man was admitted for dysuria. He had been irradiated 60Co for malignant lymphoma of tonsils 2 years earlier. The findings of palpation of prostate, retrograde urethrogram and urethroscopy strongly suggested benign prostatic hypertrophy. Retropubic prostatectomy was performed and 18 g of "adenoma" was resected. By histological observation, the "adenoma" proved to be malignant lymphoma. This tumor belonged to follicular lymphoma, medium-sized cell type of LSG non-Hodgkin's lymphoma classification. After the operation, he left our hospital for a personal reason and received systemic chemotherapy at another hospital. 相似文献