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891.
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894.
The prognosis of patients with allograft IgA nephropathy (IgAN) requires further investigation. We performed a bicenter retrospective cohort study on kidney transplant recipients diagnosed with IgAN in allograft biopsy. Recipients without allograft IgAN but with known IgAN before transplantation were included as the control group. We investigated the associations between clinicopathological characteristics, including allograft crescents, and the risk of death‐censored graft failure. In total, 1256 IgAN patients in both pre‐ and posttransplant stages were included. Among them, 559 were diagnosed with allograft IgAN, which was a time‐dependent risk factor for worse prognosis (adjusted hazard ratio = 5.009 [3.610‐6.951]; P < .001) during a median of 8.1 years of follow‐up. Of the patients with allograft IgAN, 88 (15.9%) had glomerular crescents, including 40 patients (7.2%) with >10% crescent formation in the total biopsied glomeruli. The presence of glomerular crescents in IgAN was associated with a worse graft prognosis, and the association was still valid with the C scores of the current Oxford classification. In conclusion, allograft IgAN is a time‐dependent event and is associated with worse graft outcomes. The pathological characteristics of allograft, particularly the degree of glomerular crescent formation, may represent important risk factors for a poor prognosis.  相似文献   
895.
Cardiac allograft vasculopathy (CAV) causes heart failure after heart transplantation (HTx), but its pathogenesis is incompletely understood. Notch signaling, possibly modulated by everolimus (EVR), is essential for processes involved in CAV. We hypothesized that circulating Notch ligands would be dysregulated after HTx. We studied circulating delta‐like Notch ligand 1 (DLL1) and periostin (POSTN) and CAV in de novo HTx recipients (n = 70) randomized to standard or EVR‐based, calcineurin inhibitor‐free immunosuppression and in maintenance HTx recipients (n = 41). Compared to healthy controls, plasma DLL1 and POSTN were elevated in de novo (P < .01; P < .001) and maintenance HTx recipients (P < .001; P < .01). Use of EVR was associated with a treatment effect for DLL1. For de novo HTx recipients, a change in DLL1 correlated with a change in CAV at 1 (P = .021) and 3 years (P = .005). In vitro, activation of T cells increased DLL1 secretion, attenuated by EVR. In vitro data suggest that also endothelial cells and vascular smooth muscle cells (VSMCs) could contribute to circulating DLL1. Immunostaining of myocardial specimens showed colocalization of DLL1 with T cells, endothelial cells, and VSMCs. Our findings suggest a role of DLL1 in CAV progression, and that the beneficial effect of EVR on CAV could reflect a suppressive effect on DLL1. Trial registration numbers— SCHEDULE trial: ClinicalTrials.gov NCT01266148; NOCTET trial: ClinicalTrials.gov NCT00377962.  相似文献   
896.
Deceased donor kidney transplantation (DDKT) rates for highly sensitized (HS) candidates increased early after implementation of the Kidney Allocation System (KAS) in 2014. However, this may represent a bolus effect, and a granular investigation of the current state of DDKT for HS candidates remains lacking. We studied 270 722 DDKT candidates from the SRTR from 12/4/2011 to 12/3/2014 (“pre‐KAS”) and 12/4/2014 to 12/3/2017 (“post‐KAS”), analyzing DDKT rates for HS candidates using adjusted negative binomial regression. Post‐KAS, candidates with the highest levels of sensitization had an increased DDKT rate compared with pre‐KAS (cPRA 98% adjusted incidence rate ratio [aIRR]:1.271.772.46 P = .001, cPRA 99% aIRR:3.184.365.98 P < .001, cPRA 99.5–99.9% aIRR:16.9124.2934.89 P < .001, and cPRA 99.9%+ aIRR: 8 .7911.5815.26 P < .001). To determine whether these changes produced more equitable access to DDKT, we compared DDKT rates of HS to non‐HS candidates (cPRA 0–79%). Post‐KAS, cPRA, 98% candidates had an equivalent DDKT rate (aIRR:0.650.941.36, P = .8) to non‐HS candidates, whereas 99% candidates had a higher DDKT rate (aIRR:1.191.682.38, P = .02). Although cPRA 99.5–99.9% candidates had an increased DDKT rate (aIRR:2.463.504.98, P < .001) compared to non‐HS candidates, cPRA 99.9%+ candidates had a significantly lower DDKT rate (aIRR:0.290.400.56, P < .001). KAS has improved access to DDKT for HS candidates, although substantial imbalance exists between cPRA 99.5–99.9% and 99.9%+ candidates.  相似文献   
897.
Mannose‐binding lectin (MBL) is a soluble pattern recognition molecule involved in complement activation. Single nucleotide polymorphisms (SNPs) in the MBL2 gene have been associated with susceptibility to infection, although data in solid organ transplant recipients remains inconclusive. This meta‐analysis was primarily aimed at investigating the association between posttransplant bacterial and fungal infection and variant alleles of MBL2 gene SNPs in the promoter/5’ untranslated region and exon 1. Cytomegalovirus (CMV) infection and/or disease were considered secondary outcomes. PubMed, EMBASE, and Web of Knowledge were searched for relevant articles up to August 2018. Eleven studies (comprising 1858 patients) were included, with liver transplant (LT) recipients accounting for 80.4% of the pooled population. As compared to high‐MBL expression haplotypes (YA/YA, YA/XA), any MBL‐deficient haplotype was associated with an increased risk of posttransplant bacterial and fungal infections (risk ratio [RR]: 1.30; P = .04). Low/null‐MBL expression haplotypes (XA/O, O/O) also increased the risk of primary outcome (RR: 1.51; P = .008) and CMV events (RR: 1.50; P = .006). No effect was observed for individual promoter SNPs. In conclusion, MBL‐deficient haplotypes are associated with a significant, albeit moderate, increase in the risk of posttransplant infection, with this association being mainly restricted to LT recipients.  相似文献   
898.
Increased risk donors (IRDs) may inadvertently transmit blood‐borne viruses to organ recipients through transplant. Rates of IRD kidney transplants in children and the associated outcomes are unknown. We used the Scientific Registry of Transplant Recipients to identify pediatric deceased donor kidney transplants that were performed in the United States between January 1, 2005 and December 31, 2015. We used the Cox regression analysis to compare patient and graft survival between IRD and non‐IRD recipients, and a sequential Cox approach to evaluate survival benefit after IRD transplants compared with remaining on the waitlist and never accepting an IRD kidney. We studied 328 recipients with and 4850 without IRD transplants. The annual IRD transplant rates ranged from 3.4% to 13.2%. IRDs were more likely to be male (= .04), black (P < .001), and die from head trauma (P = .006). IRD recipients had higher mean cPRA (0.085 vs 0.065, P = .02). After multivariate adjustment, patient survival after IRD transplants was significantly higher compared with remaining on the waitlist (adjusted hazard ratio [aHR]: 0.48, 95% CI: 0.26‐0.88, P = .018); however, patient (aHR: 0.93, 95% CI: 0.54‐1.59, P = .79) and graft survival (aHR: 0.89, 95% CI: 0.70‐1.13, P = .32) were similar between IRD and non‐IRD recipients. We recommend that IRDs be considered for transplant in children.  相似文献   
899.
In kidney transplantation, BK virus infection has historically resulted in high rates of graft dysfunction and graft loss. Unlike other opportunistic infections, no therapies have been shown to prevent BK. The purpose of the current study was to evaluate the safety and efficacy of ciprofloxacin for the prevention of BK viremia in kidney transplant recipients. Two hundred kidney transplant recipients were enrolled in a prospective, randomized, double‐blind, placebo‐controlled trial comparing a 3‐month course of ciprofloxacin (n = 133) vs placebo (n = 67) for the prevention of BK viremia. The primary endpoint of BK viremia at month 6 posttransplant occurred in 25 (18.8%) patients in the ciprofloxacin group and 5 (7.5%) in the placebo group (P = .03). Higher rates of BK viremia (23.3% vs 11.9%; P = .06) and BK nephropathy (5.8% vs 1.5%; P = .26) remained at 12 months in the ciprofloxacin group. Ciprofloxacin use was associated with a significantly higher rate of fluoroquinolone‐resistant gram‐negative infections (83.3% vs 50%; P = .04). A 3‐month course of ciprofloxacin was ineffective at preventing BK viremia in kidney transplant recipients and was associated with an increased risk of fluoroquinolone‐resistant infections. Clinical trial registration number: NCT01789203.  相似文献   
900.
The impact of postreperfusion syndrome (PRS) during liver transplantation (LT) using donor livers with significant macrosteatosis is largely unknown. Clinical outcomes of all patients undergoing LT with donor livers with moderate macrosteatosis (30%‐60%) (N = 96) between 2000 and 2017 were compared to propensity score matched cohorts of patients undergoing LT with donor livers with mild macrosteatosis (10%‐29%) (N = 96) and no steatosis (N = 96). Cardiac arrest at the time of reperfusion was seen in eight (8.3%) of the patients in the moderate macrosteatosis group compared to one (1.0%) of the patients in the mild macrosteatosis group (P = .02) and zero (0%) of the patients in the no steatosis group (P = .004). Patients in the moderate macrosteatosis group had a higher rate of PRS (37.5% vs 18.8%; P = .004), early allograft dysfunction (EAD) (76.4% vs 25.8%; P < .001), renal dysfunction requiring continuous renal replacement therapy following transplant (18.8% vs 8.3%; P = .03) and return to the OR within 30 days (24.0% vs 7.3%; P = .002), than the no steatosis group. Both long‐term patient (P = .30 and P = .08) and graft survival (P = .15 and P = .12) were not statistically when comparing the moderate macrosteatosis group to the mild macrosteatosis and no steatosis groups. Recipients of LT using livers with moderate macrosteatosis are at a significant increased risk of PRS. If patients are able to overcome the initial increased perioperative risk of using these donor livers, long‐term graft survival does not appear to be different than matched recipients receiving grafts with no steatosis.  相似文献   
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