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101.
Scott L. Nyberg Arthur J. Matas Walter K. Kremers Jeffrey D. Thostenson Timothy S. Larson Mikel Prieto Michael B. Ishitani Sylvester Sterioff Mark D. Stegall 《American journal of transplantation》2003,3(6):715-721
We previously proposed a quantitative approach to assess donor organs for cadaver renal transplantation. To improve on our original scoring system, we studied 34 324 patients who received cadaver renal transplants from adult donors between 1994 and 1999 and were reported to the UNOS Scientific Renal Transplant Registry. A scoring system was developed from five donor variables (age, 0-25 points; history of hypertension, 0-4; creatinine clearance before procurement, 0-4; cause of death, 0-3; HLA mismatch, 0-3) that showed a significant correlation with renal function and long-term graft survival. Cadaver kidneys were stratified by cumulative donor score: grade A, 0-9 points; grade B, 10-19; grade C, 20-29; and grade D, 30-39. The influence of donor score on renal function and graft survival was most severe above 20 points, designated 'marginal' kidneys. In summary, a donor scoring system developed from a large population database was useful in predicting outcome after cadaver renal transplantation. The improved system provides a quantitative approach to evaluation of marginal kidneys and may improve allocation of these organs in cadaver renal transplantation. 相似文献
102.
本文研究了~(60)Co-γ射线照射后HeLa细胞的存活曲线,比较了两种数学模式拟合的结果.拟合优度以对误差加权的残差平方和(Q)作为统计指标进行评价.结果表明模式的拟合度较模式为优. 相似文献
103.
Recent studies of mortality from motor neurone disease (MND) in Sweden have demonstrated rising levels of mortality from the disease, especially amongst older age groups. Case-control investigations have suggested that certain environmental factors are significantly related to variations in mortality from the disease, and are associated with a probable individual susceptibility to MND. This study applies an innovative epidemiological technique to longitudinal and cohort analysis of Swedish mortality from MND during the period 1961 to 1990. Survival modelling shows that a subpopulation susceptible to MND exists in Sweden, as has been demonstrated in other countries. The increased life expectancy of the Swedish population since 1961 has resulted in more of that susceptible population living to the ages at which MND is expressed, explaining the majority of the increase in mortality from the disease. However, environmental factors may play a role in accelerating the course of MND and may affect the timing of death within the susceptible sub-population. 相似文献
104.
Levin Adeera; Djurdjev Ognjenka; Duncan John; Rosenbaum Debbie; Werb Ron 《Nephrology, dialysis, transplantation》2006,21(2):370-377
Haemoglobin (Hgb) levels are known to be associated with numerousadverse outcomes in both chronic kidney disease (CKD) and non-CKDpatients. This analysis evaluates the association of baseline haemoglobinlevels on survival in CKD patients, who are followed by nephrologists,irrespective of glomerular filtration rate (GFR), prior to initiationof renal replacement therapy (RRT) and erythropoietin hormonereplacement therapy. Analysis of data from the provincial database (PROMIS, PatientRegistration and Outcome Management Information System) in BritishColumbia, Canada, was undertaken. Records used for the analysisincluded all CKD patients at first registration: GFR <60ml/min/1.73 m2, not yet on dialysis, starting from May 1998to October 2002, and who had complete data (defined as age andgender, diabetic status, eGFR and Hgb levels). The primary objective of this study was to determine the associationof Hgb and survival controlling for eGFR at first registrationvalue, age, gender and diabetic status. Multivariate Cox proportionalhazards analysis with time to death as outcome variable wasperformed. The cohort included 3028 patients: the mean age was 65 years,28% were diabetic, and the mean eGFR in the cohort was 21 ml/min/1.73m2. The cohort is representative of the BC CKD and dialysispopulation regarding ethnicity: 64% Caucasian, 32% Asian. Medianfollow-up was 27 months, 1 year survival was 0.92, 2 year survivalwas 0.85. Hgb at initial registration is a statistically independentpredictor of survival (RR = 0.875 for every 10 g/l, 95% CI:0.8350.917, P = 0.0001), after adjusting for age, gender,diabetic status and baseline eGFR. Further analysis, controllingfor RRT, demonstrated a similar association between Hgb andsurvival (RR = 0.853 for every 10 g/l, 95% CI: 0.7990.910,P = 0.0001), after adjusting for above variables. Substantialvariation in Hgb values exists at all GFR levels. These findings underscore the importance of evaluating Hgb atall GFR levels, and the need to study the impact of modificationof Hgb at different GFR levels on survival. 相似文献
105.
Thick malignant melanomas in general tend to have a poor prognosis, but exceptions occur where there may be no further recurrence. The reasons for this difference in clinical behaviour are not fully understood. We have looked at thick malignant melanomas (greater than 3.0 mm) in the East of Scotland that have no evidence of metastasis after a minimum of 6 years follow-up and compared the clinical and histological features with a similar group, associated with histological evidence of metastasis and/or death. Both groups received similar treatment regimes. We have identified 41 patients with thick melanomas in the former group. When compared with the control group, factors found to be significantly different between the two groups were: the nature of the lower margin of the tumour; vascular invasion; and anatomical location. 相似文献
106.
SRTR Center-Specific Reporting Tools: Posttransplant Outcomes 总被引:3,自引:2,他引:1
D. M. Dickinson T. H. Shearon J. O'Keefe H. -H. Wong C. L. Berg J. D. Rosendale F. L. Delmonico R. L. Webb R. A. Wolfe 《American journal of transplantation》2006,6(5P2):1198-1211
Measuring and monitoring performance—be it waiting list and posttransplant outcomes by a transplant center, or organ donation success by an organ procurement organization and its partnering hospitals—is an important component of ensuring good care for people with end-stage organ failure. Many parties have an interest in examining these outcomes, from patients and their families to payers such as insurance companies or the Centers for Medicare and Medicaid Services; from primary caregivers providing patient counseling to government agencies charged with protecting patients.
The Scientific Registry of Transplant Recipients produces regular, public reports on the performance of transplant centers and organ procurement organizations. This article explains the statistical tools used to prepare these reports, with a focus on graft survival and patient survival rates of transplant centers—especially the methods used to fairly and usefully compare outcomes of centers that serve different populations. The article concludes with a practical application of these statistics—their use in screening transplant center performance to identify centers that may need remedial action by the OPTN/UNOS Membership and Professional Standards Committee. 相似文献
The Scientific Registry of Transplant Recipients produces regular, public reports on the performance of transplant centers and organ procurement organizations. This article explains the statistical tools used to prepare these reports, with a focus on graft survival and patient survival rates of transplant centers—especially the methods used to fairly and usefully compare outcomes of centers that serve different populations. The article concludes with a practical application of these statistics—their use in screening transplant center performance to identify centers that may need remedial action by the OPTN/UNOS Membership and Professional Standards Committee. 相似文献
107.
G. Karam J.-F. Hétet F. Maillet J. Rigaud M. Hourmant J.-P. Soulillou M. Giral 《American journal of transplantation》2006,6(2):352-356
The aim of this retrospective study of a cohort of 1787 consecutive kidney transplantations was to analyze the risk factors associated with the occurrence of ureteral stenosis and the impact of ureteral stenosis on graft and patient survival. Between January 1990 and December 2002, 1787 renal transplantations were performed at our center. Only stenosis observed after the first month, were considered. Among the parameters studied were: donor age and serum creatinine before procurement; recipient age, cold ischemia time, delayed graft function (DGF), number of arteries and the presence of a double J stent. The follow-up parameters were the number and timing of acute rejection episodes, cytomegalovirus (CMV) infection, acute pyelonephritis, renal function and death. Ureteral stenosis occurred in 4.1% of patients and was correlated with donor age > 65 years (p = 0.001), kidneys with more than 2 arteries (p = 0.009) and DGF (p = 0.016). Ureteral stenosis did not affect 10-year patient and graft survival rates, which were respectively 90% and 64% for the stenosis group, 86% and 63% for the no-stenosis group (p = NS). These data suggest an important role for donor age, number of renal arteries and DGF for the occurrence of ureteral stenosis following renal transplantation. 相似文献
108.
Primary peritoneal carcinoma in a UK cancer center: comparison with advanced ovarian carcinoma over a 5-year period 总被引:1,自引:0,他引:1
K.S. JAABACK L. LUDEMAN† N.L. CLAYTON‡ & L. HIRSCHOWITZ† 《International journal of gynecological cancer》2006,16(S1):123-128
Abstract. Jaaback KS, Ludeman L, Clayton NL, Hirschowitz L. Primary peritoneal carcinoma in a UK cancer center: comparison with advanced ovarian carcinoma over a 5-year period. Int J Gynecol Cancer 2006; 16(Suppl. 1): 123–128.
The relative incidence of primary peritoneal carcinoma (PPCa) and advanced (FIGO stage III or IV) ovarian serous carcinoma (AOSCa) was assessed over 5 years at a UK cancer center, and the sociodemographic, clinical, and survival data were compared. There were 23 women with PPCa and 55 with AOSCa. The ratio of PPCa:AOSCa was higher than previously reported. No statistical difference was found between the two groups with regard to age (mean 64.43 vs 64.07 years, P = 0.9), parity (1.6 vs 1.8, P = 1.0), personal/family history of another malignancy (although five patients with AOSCa but none with PPCa had personal histories of breast cancer), or serum CA125, CA19.9, and carcinoembryonic antigen (CEA) levels. Similar numbers in both groups had malignant ascites, although 5.8% of patients with AOSCa but none with PPCa had negative cytology. Tumor grade, stage, treatment, and survival were similar (median 586 vs 641 days, P = 0.66). This analysis of the largest published UK series of patients with PPCa does not support previous reports that patients with PPCa are older than those with AOSCa and have a worse prognosis; it suggests that both groups have similar sociodemographic characteristics, clinical profiles, and survival. 相似文献
The relative incidence of primary peritoneal carcinoma (PPCa) and advanced (FIGO stage III or IV) ovarian serous carcinoma (AOSCa) was assessed over 5 years at a UK cancer center, and the sociodemographic, clinical, and survival data were compared. There were 23 women with PPCa and 55 with AOSCa. The ratio of PPCa:AOSCa was higher than previously reported. No statistical difference was found between the two groups with regard to age (mean 64.43 vs 64.07 years, P = 0.9), parity (1.6 vs 1.8, P = 1.0), personal/family history of another malignancy (although five patients with AOSCa but none with PPCa had personal histories of breast cancer), or serum CA125, CA19.9, and carcinoembryonic antigen (CEA) levels. Similar numbers in both groups had malignant ascites, although 5.8% of patients with AOSCa but none with PPCa had negative cytology. Tumor grade, stage, treatment, and survival were similar (median 586 vs 641 days, P = 0.66). This analysis of the largest published UK series of patients with PPCa does not support previous reports that patients with PPCa are older than those with AOSCa and have a worse prognosis; it suggests that both groups have similar sociodemographic characteristics, clinical profiles, and survival. 相似文献
109.
Chemokine receptor CCR6 as a prognostic factor after hepatic resection for hepatocellular carcinoma 总被引:3,自引:0,他引:3
HIROKI UCHIDA YUKIO IWASHITA ATSUSHI SASAKI KOHEI SHIBATA TOSHIFUMI MATSUMOTO MASAYUKI OHTA SEIGO KITANO 《Journal of gastroenterology and hepatology》2006,21(1):161-168
Background and Aims: Chemokines and their receptors have recently been shown to have major roles in cancer metastasis. The aim of this study was to determine whether the interaction between chemokine receptor 6 (CCR6) and its ligand, macrophage inflammatory protein‐3 alpha (MIP‐3α), correlates with metastasis of hepatocellular carcinoma (HCC). Methods: To observe the reaction of CCR6 expressed cancer cells to MIP‐3α stimulation, chemotactic and actin polymerization assays for both CCR6 high cells (HepG2) and CCR6 low cells (MCF‐7) were performed. CCR6 mRNA levels in tumor specimens from 30 HCC patients were quantified by real‐time polymerase chain reaction. Patients were classified into two groups, high (≥ 20 copies; n = 10) CCR6 and low (<20 copies; n = 20) CCR6 on the basis of CCR6 expression, and the groups were compared with respect to clinicopathological features. Results: When HepG2 cells (CCR6 high) were stimulated with MIP‐3α, they migrated in a dose‐dependent manner, and formation of pseudopodia was observed. These phenomena were not observed in the CCR6 low cells. The incidence of intrahepatic metastasis was higher in the high CCR6 expression group than in the low CCR6 expression group (P < 0.05). Disease‐free survival was significantly poorer in the high CCR6 expression group than in the low CCR6 expression group (P < 0.05). Conclusions: It was indicated that CCR6 might be associated with intrahepatic metastasis of HCC and might be able to become one of the prognostic factor after hepatic resection for HCC. 相似文献
110.
Survival after intensive care 总被引:2,自引:0,他引:2