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IntroductionSemen induces mucosal changes in the female reproductive tract to improve pregnancy outcomes. Since semen‐induced alterations are likely short‐lived and genital inflammation is linked to HIV acquisition in women, we investigated the contribution of recent semen exposure on biomarkers of genital inflammation in women at high HIV risk and the persistence of these associations.MethodsWe assessed stored genital specimens from 152 HIV‐negative KwaZulu‐Natal women who participated in the CAPRISA 008 trial between November 2012 and October 2014. During the two‐year study period, 651 vaginal specimens were collected biannually (mean five samples per woman). Cervicovaginal lavage (CVL) was screened for prostate‐specific antigen (PSA) by ELISA, whereas Y‐chromosome DNA (YcDNA) detection and quantification were conducted by RT‐PCR, representing semen exposure within 48 hours (PSA+YcDNA+) and semen exposure within three to fifteen days (PSA−YcDNA+). Soluble protein concentrations were measured in CVLs by multiplexed ELISA. T‐cell frequencies were assessed in cytobrushes by flow‐cytometry, and vulvovaginal swabs were used to detect common vaginal microbes by PCR. Linear mixed models adjusting for factors associated with genital inflammation and HIV risk were used to assess the impact of semen exposure on biomarkers of inflammation over multiple visits.ResultsHere, 19% (125/651) of CVLs were PSA+YcDNA+, 14% (93/651) were PSA−YcDNA+ and 67% (433/651) were PSA−YcDNA−. Semen exposure was associated with how often women saw their partners, the frequency of vaginal sex in the past month, HSV‐2 antibody detection, current gonorrhoea infection and Nugent Score. Both PSA detection (PSA+YcDNA+) and higher cervicovaginal YcDNA concentrations predicted increases in several cytokines, barrier‐related proteins (MMP‐2, TIMP‐1 and TIMP‐4) and activated CD4+CCR5+HLA‐DR+ T cells (β = 0.050; CI 0.001 to 0.098; p = 0.046) and CD4+HLA‐DR+ T cells (β = 0.177; CI 0.016 to 0.339; p = 0.032) respectively. PSA detection was specifically associated with raised pro‐inflammatory cytokines (including IL‐6, TNF‐α, IP‐10 and RANTES), and with the detection of BVAB2 (OR = 1.755; CI 1.116 to 2.760; p = 0.015), P. bivia (OR = 1.886; CI 1.102 to 3.228; p = 0.021) and Gardnerella vaginalis (OR = 1.815; CI 1.093 to 3.015; p = 0.021).ConclusionsMore recent semen exposure was associated with raised levels of inflammatory biomarkers and the detection of BV‐associated microbes, which declined by three to fifteen days of post‐exposure. Although transient, semen‐induced alterations may have implications for HIV susceptibility in women.  相似文献   
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Transplantation of organs continues to be a primary therapeutic modality for treatment of end-stage organ disease, and 1-year graft survival rates show increasing improvements for most organs. A number of transplant centers show 1-yr graft survival rates approaching 90% or more for the kidney, liver and pancreas. Rejection continues to be the major cause for loss of organs and there is still a major shortage of organs for transplantation. Additionally, many organs showed delayed graft function (or primary nonfunction) which may be related to either donor factors or preservation factors. The University of Wisconsin solution for organ preservation has increased the safe time of preservation for the liver, kidney, and pancreas and helped to increase the quality and number of organs available for transplantation. However, the long-range goal of organ preservation (unlimited preservation) is still far from being reached. In the past, preservation could accurately be categorized as an art and preservation solutions were developed based upon theoretical rationales about the mechanisms of organ injury at hypothermia and what agents would suppress injury. The utility and success of this approach is exemplified by the developments of Collins solution and the UW solution. However, further developments in methods to increase the quality and duration of preservation of all transplantable organs would appear to be dependent upon defining, systematically, how organs are injured and what can be done to suppress the injury.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
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Background: Three cases of heparin-induced thrombocytopenia (HIT) were observed in patients undergoing isolated limb perfusion (ILP) with melphalan. This occurrence prompted the discontinuation of prophylactic postoperative heparin in ILP patients and its avoidance in patients undergoing isolated hepatic perfusion (IHP). The need to reassess these decisions led to a review of thrombocytopenia in both patient populations.Methods: Records of all patients treated with ILP or IHP at our institution from July 1992 through November 1996, were reviewed. Nine IHP patients were tested prospectively for heparinrelated antibodies using serum samples obtained perioperatively and during the second postoperative week.Results: Thrombocytopenia (<100,000 platelets/L) developed postoperatively in 30% of 131 ILP patients and in 77% of 56 IHP patients. No cases of HIT were identified other than the three who had been previously diagnosed. The prevalence of HIT in heparinized ILP patients was 2.8% (3/108). All nine IHP patients developed heparin-related antibodies postoperatively.Conclusions: Because the prevalence of HIT following ILP is in the range observed in other clinical settings, postoperative heparin prophylaxis is an option. However, it probably should be limited to the first week, and daily platelet counts should be reviewed for a pattern of thrombocytopenia consistent with HIT. The prevalence of heparin-related antibodies after IHP is so high that prophylactic heparin should be avoided in this setting.  相似文献   
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PURPOSE: The prognostic relevance of the rate of decline of serum alpha-fetoprotein (AFP) and human chorionic gonadotropin (HCG) during the first 3 weeks of chemotherapy for nonseminomatous germ cell tumors (NSGCT) was studied in the context of the International Germ Cell Cancer Collaborative Group (IGCCCG) classification. PATIENTS AND METHODS: Data from 653 patients prospectively recruited in clinical trials were studied. Tumor markers were obtained before chemotherapy and 3 weeks later. Decline rates were calculated using a logarithmic formula and expressed as a predicted time to normalization (TTN). A favorable TTN was defined when both AFP and HCG had a favorable decline rate, including cases with normal values. RESULTS: The median follow-up was 50 months (range, 2 to 151 months). Tumor decline rate expressed as a predicted TTN was associated with both progression-free survival (PFS; P <.0001) and overall survival (OS; P <.0001). The 4-year PFS rates were 64% and 38% in patients from the poor-prognosis group who had a favorable and an unfavorable TTN, respectively. The 4-year OS rates were 83% and 58%, respectively. This effect was independent from the initial tumor marker values, the primary tumor site, and the presence of nonpulmonary visceral metastases: tumor marker decline rate remained a strong predictor for both PFS (hazard ratio = 2.5; P =.01) and OS (hazard ratio = 4.6; P =.002) in patients from the IGCCCG poor-prognosis group in multivariate analysis. CONCLUSION: Early predicted time to tumor marker normalization is an independent prognostic factor in patients with poor-prognosis NSGCT and may be a useful tool in the therapeutic management of these patients.  相似文献   
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Achieving optimal outcomes after radical prostatectomy.   总被引:4,自引:0,他引:4  
PURPOSE: The most favorable outcome that can be achieved after radical prostatectomy is complete tumor resection without recurrence and full recovery of continence and potency. Risks of erectile dysfunction, incontinence, and disease recurrence are well described, but in isolation, do not adequately inform patients of the possibility of becoming cancer-free while at the same time returning to their preoperative functional state. We sought to determine the frequency of optimal outcomes after radical prostatectomy and the time to such outcomes. PATIENTS AND METHODS: Patients who underwent radical prostatectomy performed at a tertiary referral center between July 1998 and July 2003 for clinical stage T1 to T3 prostate cancer were identified. Patients were excluded if they were incontinent or impotent preoperatively, or if they had received radiotherapy or neoadjuvant androgen deprivation therapy previously. Six hundred forty-seven patients were analyzed for time to recovery of full continence and potency without cancer recurrence after surgery. Optimal outcome probability was calculated with a Markov state transition model to simulate clinical outcomes in the first 4 years following radical prostatectomy. RESULTS: Mean patient age was 58 years, and mean pretreatment prostate-specific antigen was 6.9 ng/mL. Cancer-free status with full continence and potency was achieved in 30% of men at 12 months, 42% at 24 months, 47% at 36 months, and 53% at 48 months postoperatively. CONCLUSION: Optimal outcomes after radical prostatectomy can be achieved in a small majority of cases. Time to full recovery is primarily dictated by recovery of erectile function. This information is helpful for patients interested in their chances of returning to their preoperative functional state.  相似文献   
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Hepatocellular carcinoma (HCC) is the most frequent primitive cancer of the liver. It mostly develops on cirrhotic livers. Orthotopic liver transplantation is the only treatment that definitively addresses both the metachronous occurrence risk of HCC and the underlying disease. Under Milan criteria, i.e. less than 3 nodules of 3 cm max in diameter, or 1 nodule of 5 cm maximum, OLT has been shown effective and provides with survival rates almost equal to those obtained with HCC free cirrhotic patients. In Rennes, 195 patients with early HCC on cirrhotic livers have been transplanted from January 1995 to June 2005. Global and disease free 8 years patient survival rates were 73 and 70%, respectively. These results were significantly altered when the recipient was female, the cirrhosis due to C virus and the patient of B blood group. Despite these excellent results, the principal limit to the application of transplantation for HCC remains the long period of time patients have to wait for a graft. During this period of time, growth of the tumour may drop the patient out of Milan criteria and subsequently from the waiting list. The role of chemoembolisation, liver resection and thermal ablation while the patient is waiting for a graft remains debatable.  相似文献   
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