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91.
In this report, we describe the first kidney retransplantation performed after anti–programmed cell death‐1 (PD‐1)–related allograft rejection. In 2014, we administered pembrolizumab (anti–PD‐1) for ~9 months to a 57‐year‐old kidney transplant recipient with metastatic cutaneous squamous cell carcinoma (CSCC). The patient experienced both a complete antitumor response and T cell–mediated allograft rejection requiring reinitiation of hemodialysis. Four‐and‐a‐half years after initiating pembrolizumab, the patient remained without evidence of CSCC relapse and received a kidney transplant from a living‐unrelated donor. Ten‐and‐a‐half months after kidney retransplantation, the allograft is functioning well and the patient's CSCC remains in remission. This case illustrates the potential for PD‐1 blockade to bring about durable immune‐mediated tumor control in chronically immunosuppressed patients, and begins to address the feasibility of kidney retransplantation in patients who have previously received immune checkpoint inhibitor therapy for cancer. Results from this and future cases may help elucidate mechanisms of antitumor immunity and allograft tolerance, and inform updates to transplant decision models. Our report also underscores the need for clinical trials testing novel immunotherapy combinations in solid organ transplant recipients designed to uncouple antitumor and anti‐allograft immunity.  相似文献   
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Controversial results exist regarding the clinical benefits of single- vs double-unit umbilical cord blood transplantation (UCBT) in patients with hematologic diseases. A systematic review was conducted to evaluate this issue. The PubMed, Embase, and Cochrane Library databases were searched up to May 2018. A total of 25 studies including 6571 recipients were identified. Although double-unit UCB contained higher doses of total nucleated cells and CD34+ cells, it offered no advantages over single-unit UCB in terms of hematologic recovery, including the rate and speed of neutrophil and platelet engraftment. Double-unit UCBT was associated with higher incidences of grades II-IV acute and extensive chronic graft-vs-host disease, accompanied by a lower relapse incidence, which may be attributed to a graft-vs-graft effect induced by double-unit UCB. However, transplant-related mortality, disease-free survival, and overall survival were comparable between single- and double-unit UCBT. Although double-unit UCBT confers no clinical advantages over single-unit UCBT, certain patients, such as those at high risk of relapse, might benefit from double-unit UCBT, a possibility that needs to be clarified in future randomized trials.  相似文献   
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Background/Purpose

Ovarian preservation is desirable in girls with benign ovarian masses. We aimed to 1) identify clinical predictors of malignant ovarian masses, 2) investigate how often ovarian tissue is present to preserve in benign masses, and 3) identify factors associated with successful ovarian preservation.

Methods

Retrospective analysis (1997–2012) of girls age 1–18 years with an ovarian mass managed operatively. Data on presenting symptoms, imaging, biochemical markers, treatment, outcome, and pathology were extracted.

Results

We identified 150 patients. Large mass size, solid components, and elevated tumor markers (AFP, βHCG, and/or LDH) were significantly predictive of malignancy. All masses < 10 cm, predominantly cystic, and with negative tumor markers were benign. Masses with all three of these characteristics would decrease a 20% malignancy pretest probability to a posttest probability of 0.25%. Benign masses managed by oophorectomy contained normal ovarian tissue in 76% of the specimens. For benign masses, successful ovarian preservation was significantly associated with size < 10 cm, predominantly cystic, laparoscopy, and absence of torsion or calcifications.

Conclusion

Ovarian masses that are < 10 cm, primarily cystic, and have negative tumor markers are most likely benign. Viable ovarian tissue is frequently present in benign masses, so significant efforts should be made for ovarian preservation.  相似文献   
99.

Purpose

Malignant tumors of the common bile duct or of the pancreas head are uncommon in childhood [Perez EA, Gutierrez JC, Koniaris LG, Neville HL, Thompson WR, Sola JE. Malignant pancreatic tumors: incidence and outcome in 58 pediatric patients. J Pediatr Surg. 2009; Jan; 44 (1): 197–203]. With radical surgery being the standard cure for nonmetastatic diseases, pancreaticoduodenectomy (PD) is the best choice when the tumor is localized in the head of the pancreas, or in the lower portion of the common bile duct. The purpose of the present study is to describe five consecutive children managed by PD, and reviewing the particular aspects and results of this rare procedure in children.

Methods

Between 2007 and 2010, five patients (median age: 7 years) underwent PD for nonmetastatic malignant tumors. In two cases, PD was performed en bloc with a right hepatectomy in order to achieve the radical resection of a recurrent biliary sarcoma. Four patients benefited from a “pylorus-preserving” PD procedure. In two patients, resection of the portal vein and vascular reconstruction was performed, and in one case, an extended resection of the biliary ductal system was necessary.

Results

All resection margins were clear. The postoperative course was uneventful, with no pancreatic or biliary leakage in all of the patients. Oral refeeding was achieved by the eighth postoperative day. In two cases, a late revision of pancreatic–jejunal anastomosis was performed because of mild steatorrea and a suspected anastomotic stricture. Two of the patients, who were subsequently operated on second hand, for biliary sarcoma, died from the recurrence; while three of the others, with pancreatic malignancies, are alive and well, with a good functional outcome.

Conclusions

Surgical resection is the treatment of choice for tumors of the pancreatic head area. In the absence of regional or metastatic extension, the radicality of primary intervention is associated with favorable outcomes. Good functionality results were observed after the PD was limited to the head of the pancreas and subject to pylorus-preserving techniques.  相似文献   
100.
BackgroundA splenectomy can reduce transfusion requirements in patients with thalassemia. However, the role of a splenectomy remains controversial because its efficacy has not yet been fully determined and there are concerns over potential complications. The purpose of this study was to assess the efficacy, potential changes in hematologic parameters, and any complications associated with splenectomy.MethodsMedical records of 50 patients with transfusion-dependent thalassemia (TDT) who had undergone a splenectomy, along with those of 20 control subjects with intact spleens, were retrospectively reviewed.ResultsThe primary outcomes indicate the efficacy of a splenectomy in reducing red cell transfusions. Fifty TDT post-splenectomy patients were included in this study, of which 28 (56%) were female. The median age of all patients was 20.5 (18–28 years of age). Twenty-seven patients (54%) transformed from TDT to non-transfusion-dependent thalassemia (NTDT) after the splenectomy; 100% with Hb H disease, 58.3% with beta-thalassemia/Hb E disease, and 23.5% with homozygous beta-thalassemia. According to multivariable logistic regression analysis, Hb H disease (adjusted OR 55.23, 95% CI 1.35–22.8.10) and receiving a splenectomy at > ten years of age (adjusted OR 25.36, 95% CI 1.62–396.47) were associated with higher responses. The prevalence of pulmonary hypertension and thromboembolic events were similar between the splenectomy patients and non-splenectomy patients.ConclusionSplenectomy reduced transfusion requirements in TDT patients. The predictive factors as a response to a splenectomy included Hb H disease amongthose receiving a splenectomy at > ten years of age.  相似文献   
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