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BACKGROUND: The frequency of subsequent testicular cancer (referred to as metachronous testicular cancer) in men who have had previous testicular cancer is relatively high. The rate of metachronous testicular cancer in men with extragonadal germ cell tumors (EGCTs), however, is largely unknown. We conducted a retrospective study of EGCT patients to determine the incidence, cumulative risk, and specific risk factors for metachronous testicular cancers. METHODS: A standardized questionnaire about patient characteristics, the extent of EGCT disease, any second malignancies, and treatments received was completed for 635 patients with EGCTs identified from the medical records of 11 cancer centers in Europe and the United States from 1975 through 1996. Comparisons with age group-specific data from the Saarland, Germany, population-based cancer registry were used to calculate the standardized incidence ratio (SIR). The Kaplan-Meier method was used to analyze survival data and cumulative risk. All statistical tests were two-sided. RESULTS: Sixteen EGCT patients (4.1%) developed metachronous testicular cancers, with a median time between diagnoses of 60 months (range, 14-102 months). The risk of developing metachronous testicular cancers was statistically significantly increased in patients with EGCTs (observed = 16; expected = 0.26; SIR = 62; 95% confidence interval [CI] = 36 to 99) and in subsets of EGCT patients with mediastinal location (SIR = 31; 95% CI = 8 to 59), retroperitoneal location (SIR = 100; 95% CI = 54 to 172), and nonseminomatous histology (SIR = 75; 95% CI = 43 to 123). The cumulative risk of developing a metachronous testicular cancer 10 years after a diagnosis of EGCT was 10.3% (95% CI = 4.9% to 15.6%) and was higher among patients with nonseminomatous EGCTs (14.3%; 95% CI = 6.7% to 21.9%) and retroperitoneal EGCTs (14.2%; 95% CI = 5.6% to 22.8%) than among patients with seminomatous EGCTs (1.4%; 95% CI = 0.0% to 4.2%) and mediastinal EGCTs (6.2%; 95% CI = 0.1% to 12.2%). CONCLUSIONS: Patients with EGCTs, particularly those with retroperitoneal or nonseminomatous tumors, but also those with primary mediastinal EGCTs, are at an increased risk of metachronous testicular cancer.  相似文献   
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PURPOSE: This randomized trial evaluated antitumor activity of and survival asociated with high-dose-intensity chemotherapy with methotrexate, vinblastine, doxorubicin, and cisplatin (MVAC) plus granulocyte colony-stimulating factor (HD-MVAC) versus MVAC in patients with advanced transitional-cell carcinoma (TCC). PATIENTS AND METHODS: A total of 263 patients with metastatic or advanced TCC who had no prior chemotherapy were randomized to HD-MVAC (2-week cycles) or MVAC (4-week cycles). RESULTS: Using an intent-to-treat analysis, at a median follow-up of 38 months, on the HD-MVAC arm there were 28 complete responses (CRs) (21%) and 55 partial responses (PRs) (41%), for an overall response of 62% (95% confidence interval [CI], 54% to 70%). On the MVAC arm, there were 12 CRs (9%) and 53 PRs (41%), for an overall response of 50% (95% CI, 42% to 59%). The P value for the difference in CR rate was.009; and for the overall response, it was.06. There was no statistically significant difference in survival (P =.122) or time to progression (P =.114). Progression-free survival was significantly better with HD-MVAC (P=.037; hazard ratio.75; 95% CI.58 to.98). The median progression-free survival time was 9.1 months on the HD-MVAC arm versus 8.2 months on the MVAC arm. The 2-year progression-free survival rate was 24.7% for HD-MVAC (95% CI, 17.1% to 32.3%) versus 11.6% for MVAC (95% CI, 5.9% to 17.4%). CONCLUSION: With HD-MVAC, it was possible to deliver twice the doses of cisplatin and doxorubicin in half the time, with fewer dose delays and less toxicity. Although a 50% difference in median overall survival was not detected, a benefit was observed in progression-free survival, CR rates, and overall response rates with HD-MVAC.  相似文献   
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Peripheral myelin protein 2 (PMP2) is a small protein located on the cytoplasmic side of compact myelin, involved in the lipids transport and in the myelination process. In the last years few families affected with demyelinating Charcot‐Marie‐Tooth neuropathy (CMT1), caused by PMP2 mutations, have been identified. In this study we describe the first case of a PMP2 in‐frame deletion. PMP2 was analyzed by direct sequencing after exclusion of the most frequent CMT‐associated genes by using a next generation sequencing (NGS) genes panel. Sanger sequencing was used for family's segregation analysis. Molecular modeling analysis was used to evaluate the mutation impact on the protein structure. A novel PMP2: p.I50del has been identified in a child with early onset CMT1 and in three affected family members. All family members show an early onset demyelinating neuropathy without other distinguish features. Molecular modeling analysis and in silico evaluations do not suggest a strong impact on the overall protein structure, but a most likely altered protein function. This study suggests the importance to add PMP2 in CMT NGS genes panels or, at most, to test it after major CMT1 genes exclusion, due to the lack of diagnostic‐addressing additional features.  相似文献   
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PEROXYNITRITE: A MEDIATOR OF INCREASED MICROVASCULAR PERMEABILITY?   总被引:3,自引:0,他引:3  
1. Increased expression of inducible nitric oxide synthase (iNOS) and subsequent elevation of nitric oxide (NO) levels at inflammatory sites have led to the suggestion that peroxynitrite (the reaction product of superoxide and NO) is involved in proinflammatory processes. The present study has investigated the ability of peroxynitrite to induce oedema formation in the rat cutaneous microvasculature. 2. Peroxynitrite was synthesized from hydrogen peroxide and acidified nitrite. Spectrophotometry was used to measure the concentration and breakdown of peroxynitrite. It was also used to determine maximum amounts of hydrogen peroxide and sodium nitrite remaining after synthesis. 3. Oedema formation in response to intradermall. (i.d.) injected peroxynitrite, hydrogen peroxide and sodium nitrite was measured by the extra vascular accumulation of i.v. [125I]-albumin in the anaesthetized rat. 4. Peroxynitrite (40,100 and 200 nmol/site) acted in a dose-dependent manner to cause a mean (± SEM) increase in plasma extravasation of 24 ± 2,55 ± 5 and 69 ± 6 μL, respectivel. (n= 4), with resulting inflammatory oedema. Peroxynitrite induced significantly larger plasma extravasation than equivalent vehicle controls at doses of 100 (P > 0.05) and 200 nmol (P > 0.001). This increased extravasation appears to be a direct microvascular response to peroxynitrite administration and not due to either a raised pH, necessary to stabilize the peroxynitrite, or contaminating concentrations of hydrogen peroxide or sodium nitrite from which peroxynitrite is formed. 5. These results suggest that peroxynitrite acts to increase microvascular permeability and oedema formation. Therefore, peroxynitrite may mediate vascular pro-inflammatory effects in addition to its direct cytotoxic activity.  相似文献   
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