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21.
Folate and methionine metabolism is involved in DNA synthesis and methylation processes. Polymorphisms in the genes of folate metabolism enzymes have been associated with some forms of cancer. In a case-control study, we evaluated whether four common polymorphisms in methylenetetrahydrofolate reductase (MTHFR C677T and A1298C), methionine synthase (MS A2756G), and methionine synthase reductase (MTRR A66G) genes may have a role in altering susceptibility to adult acute lymphoblastic leukemia (ALL) and non-Hodgkin's lymphoma (NHL). We analyzed DNA of 120 adult ALL, 200 NHL, and 257 healthy control subjects. Individual carrying the MTHFR 677TT genotype showed a 3.6-fold decreased ALL risk [odds ratio (OR) 0.28, 95% confidence interval (95% CI) 0.12-0.72] than wild-types. Similarly, MS 2756GG individuals showed a 5.0-fold decreased ALL risk (OR 0.20, 95% CI 0.02-1.45) than wild-types. In combined results, subjects with the MTHFR 677CT/TT and MS 2756AG/GG genotypes revealed a 3.6-fold ALL risk reduction (OR 0.28, 95% CI 0.14-0.58) and those with the MTHFR 677TT and MTRR 66AG genotypes revealed a 4.2-fold ALL risk reduction (OR 0.24, 95% CI 0.06-0.81). Finally, those with the MS 2756AG/GG and MTRR 66AG/GG genotypes revealed a 2.2-fold ALL risk reduction (OR 0.45, 95% CI 0.10-0.85). Single analysis for NHL did not show any significant difference for all the polymorphisms investigated, but in the low-grade NHL subgroup, we found a 2.0-fold risk reduction for the MTRR 66GG homozygous genotype (OR 0.50, 95% CI 0.25-0.99), which was higher (OR 0.37, 95% CI 0.14-0.85) when analyzed in combination with MS 2756AA genotype. These data are in accordance with the hypothesis that polymorphisms in the genes for folate and methionine metabolism might play a greater role in the occurrence of ALL than NHL by influencing DNA synthesis and/or DNA methylation.  相似文献   
22.
Some studies have demonstrated antidepressant activity of neurokinin-1-receptor antagonists (NK-1-RA) in major depressive disorder. However, the underlying mechanisms of this antidepressant effect are largely unknown. Preclinical studies in rats and mice have suggested that NK-1-RA do increase the neuronal release of serotonin (5-HT). This, however, seems to be compensated by an increased 5-HT reuptake, indicating that NK-1-RA have no inhibitory effect on the 5-HT transporter in rodents. Given the possibility that modulation of neurotransmitter release and reuptake may differ between species, with major differences found between rodents and humans, we investigated for the first time the possible modulatory effect of NK-1-RA on 5-HT uptake in human brain synaptosomes and compared it with the situation in rat cortex. We found that the specific human NK-1-RA L-733060, in contrast to the SSRI fluvoxamine (IC50 = 10− 7.96 M) did not inhibit 5-HT uptake in human brain synaptosomes and did not modulate fluvoxamine-induced 5-HT uptake inhibition at 1 μM. Furthermore, substance P as well as Sar9Met(O2)11SP, as the major agonists at the NK-1-R, did not modulate 5-HT uptake in human brain synaptosomes. Similar results were found in rat cortex synaptosomes by using the rat-specific NK-1-RA WIN51708. These results show that in humans, as in rodents, inhibition of the 5-HT transporter is probably not the underlying mechanism of the assumed antidepressant activity of NK-1-RA.  相似文献   
23.
Geometric cis, trans isomers, derivatives of 2-substituted-1,3-dioxanes were designed and studied as antimuscarinic agents. The synthesized compounds were evaluated as perchlorides and methiodides by functional tests with rabbit vas deferens (putative M1), guinea-pig heart (M2) and guinea-pig ileum (M3). The effect of the replacement of a trimethylammonium group with a dimethysulfonium in the two rings was also evaluated. Pharmacological results indicate that the 1,3-dioxane nucleus shows the highest stereoselective values on the studied receptors.  相似文献   
24.
Simple SummaryGlioblastoma is an aggressive brain tumor with a dismal prognosis. In a minority of cases, it presents with multiple lesions already at the time of diagnosis, affecting patients’ survival and treatment. Our retrospective study aims to increase the current understanding and define a treatment for this sub-entity, to improve patient survival. Chemoradiotherapy is a also safe and efficacy treatment in patients with multiple lesions. Survival advantages from extensive resection remain unclear.AbstractGlioblastomas with multiple foci at presentation (mGBMs) account for 2–35% of all GBMs. mGBMs have limited existing data and no standardized treatment. This study aims to determine their incidence, demographic and clinical features, outcome, and prognostic factors in terms of overall survival. We performed a monocentric retrospective study, reviewing patients treated at the Istituto Oncologico Veneto. Inclusion criteria were: new diagnosis of GBM and presence of multiple lesions on pre-treatment MRI. ECOG PS was used to evaluate clinical condition, RANO criteria for radiological assessment, and CTCAE v5.0 for treatment-related adverse events. The incidence of newly diagnosed mGBM was 7.2% and the study population consisted of 98 patients. Median age was 63 years, M:F ratio of 1.8:1, and a surgical approach was undertaken in 73 patients (mostly partial resection). MGMT was methylated in 47.5%, and 82 patients received active oncological treatment (65.9% radiotherapy plus temozolomide (RT + TMZ)). The disease control rate with RT + TMZ was 63%. Median OS of the entire study population was 10.2 months (95% CI 6.6–13.8), and median PFS was 4.2 months (95% CI 3.2–5.2). The ECOG PS, the extent of resection, and the RT + TMZ were significant prognostic factors in the univariate analysis for OS, but only the RT + TMZ was a significant independent OS predictor in the multivariate analysis (HR = 3.1, 95% IC 1.3–7.7, p = 0.014). The incidence of mGBM is not rare. RT + TMZ is confirmed to be an independent prognostic factor for survival and a safe and effective treatment. When feasible, RT + TMZ should be considered as a possible first-line treatment. The role of the extent of resection is still unclear.  相似文献   
25.
Purpose The purpose of the study was to evaluate the effect on visual function of orally administered CDP-choline in addition to patching for the treatment of amblyopia in children. Methods This was an open label parallel group study comparing patching plus oral CDP-choline with patching alone. Sixty-one participants (aged between 5 and 10 years) suffering from anisometropic or strabismic amblyopia were divided at random into two groups: Group A, 800 or 1,200 mg (according to the body weight) of orally administered CDP-choline and 2-h patching a day; Group B, 2-h patching a day. Both groups were treated for 30 consecutive days. A follow-up visit was set 60 days after the treatment was discontinued. The main outcome measure was the change in visual acuity of amblyopic eyes as measured by Snellen’s E charts. The secondary outcome measures were changes in the visual acuity of amblyopic eye as measured by isolated letters (Snellen’s E) and changes in the contrast sensitivity of amblyopic eyes. Results The addition of CDP-choline to patching therapy was not found to be more effective than patching alone after 30-day treatment. The present results showed that adding CDP-choline to patching stabilised the effects obtained during the treatment period. In fact, whereas the participants treated only with patching showed a decrease in visual acuity at 90 days, these receiving CDP-choline and patching combined appeared to maintain the results obtained (two-way ANOVA: P = 0.0042). Similar results were obtained when measuring visual acuity by isolated Snellen’s E letters. Conclusions In amblyopic patients, CDP-choline combined with patching contributes to obtaining more stable effects than patching alone. Fabio De Gregorio works as an advisor for Tubilux Pharma S.p.A. The authors have full control of all primary data and they agree to allow Graefe’s Archives for Clinical and Experimental Ophthalmology to review their data if requested.  相似文献   
26.
IntroductionDiabetic patients treated with metformin have a lower risk of developing BC or a better BC prognosis. Metformin might reduce cancer growth through direct antiproliferative effects or through indirect mechanisms, particularly the reduction of insulin. In a randomized study on nondiabetic BC patients in natural menopause with high testosterone levels, we observed a significant decrease in insulin and in testosterone levels with metformin 1500 mg/d compared with 1000 mg/d. We present the results of a new analysis of our study on the effect of metformin on the bioavailability of sex hormones.Patients and MethodsOne hundred twenty-four eligible women were initially invited to take metformin 500 mg/d for 3 months. The 108 women who completed the first 3 months continued the study using 1000 mg/d for 1 month. The women were then randomized into 2 groups, and, for the subsequent 5 months, 1 group increased the dose to 1500 mg/d, and the other group continued with 1000 mg/d.ResultsNinety-six women completed the study, 43 receiving metformin 1500 mg/day, and 53 receiving 1000 mg/day. The women receiving 1500 mg/d showed a greater and significant reduction of free testosterone (?29%) and estradiol (?38%), a borderline significant reduction of estrone and insulin-like growth factor-1, and a nonsignificant reduction of androstenedione. They also showed a nonsignificant increase of dehydroepiandrosterone sulfate.ConclusionMetformin does not interfere with the production of dehydroepiandrosterone sulfate. Besides, it decreases estradiol levels, basically through the reduction of testosterone. These hormonal changes might have clinical relevance.  相似文献   
27.
OBJECTIVES: Detection of free fetal DNA (ffDNA) in maternal blood during pregnancy has given rise to the possibility of developing new noninvasive approaches for early prenatal diagnosis.On a large-scale study, two protocols of real-time polymerase chain reaction (PCR) were compared in order to establish which Y-specific locus, either multicopy DYS14 or single copy SRY sequence, was the most suitable for developing a test with high diagnostic efficiency for early fetal gender assessment. The second aim was to assess whether the combination of the two detection systems could increase the performance of the prenatal test. METHODS: We analyzed 145 plasma samples from healthy pregnant women between 11 and 12 weeks of singleton gestation. For each sample, fetal gender was determined by using both protocols (DYS14 and SRY) during the same real-time PCR run. RESULTS: The data obtained by the DYS14 and SRY assays showed an efficiency in fetal gender prediction of 97.9 and 80%, respectively. It is not advisable to combine the two protocols because this association does not help in further improvements in fetal gender prediction. CONCLUSIONS: DYS14 assay is the best approach for early fetal gender assessment because it is more sensitive, accurate, and efficient than the SRY assay.  相似文献   
28.
29.
ObjectiveOnly approximately 15% of patients with lung cancer are suitable for surgery and clinical postoperative outcomes vary. The aim of this study was to investigate variables associated with post-surgery respiratory failure in this patient cohort.MethodsPatients who underwent surgery for lung cancer were retrospectively studied for respiratory function. All patients had undergone lung resection by a mini-thoracotomy approach. The study population was divided into two subgroups for comparison: lobectomy group, who underwent lobar resection; and sub-lobar resection group.ResultsA total of 85 patients were included, with a prevalence of lung cancer stage IA and adenocarcinoma histotype. Lobectomy (versus sub-lobar resection), the presence of chronic obstructive pulmonary disease (COPD), and a COPD assessment test (CAT) score >10, were all associated with an increased risk of respiratory failure. The partial pressure of arterial oxygen decreased more in the lobectomy group than in the sub-lobar resection group following surgery, with a significant postoperative between-group difference in values. Postoperative CAT scores were also better in the sub-lobar resection group.ConclusionsPost-surgical variations in functional parameters were greater in the group treated by lobectomy. COPD, high CAT score and surgery type were associated with postoperative development of respiratory failure.  相似文献   
30.
Introduction: Roux-en-Y gastric bypass (RYGB) and one anastomosis gastric bypass (OAGB) are two effective bariatric surgical procedures with positive outcomes in terms of weight loss, comorbidities remission, and adverse events profiles. OAGB seems to carry a higher risk of malnutrition, but existing data are controversial. The aim of this study is to objectively evaluate and compare malnutrition in patients undergoing RYGB and OAGB. Methods: Retrospective monocentric study of obese patients undergoing RYGB or OAGB between the 15 September 2020 and the 31 May 2021. Nutritional status was assessed using the Controlling Nutritional Status (CONUT) score and compared between groups. The primary outcome was the mean CONUT score at 6 months. The secondary outcomes included the incidence of malnutrition, comorbidities, including hypertension, insulin resistance and type II diabetes mellitus, and weight loss. Results: 78 patients were included: 30 underwent RYGB and 48 underwent OAGB. At 6-Month Follow-Up there was no difference between groups in the mean CONUT score nor in incidence of malnutrition. In both groups, the nutritional status significantly worsened 6 months after surgery (preoperative and postoperative score of 0.48 ± 0.9 and 1.38 ± 1.5; p = 0.0066 for RYGB and of 0.86 ± 1.5 and 1.45 ± 1.3; p = 0.0422 for OAGB). Type II Diabetes mellitus (DMII) and hypertension remission were significant in the OAGB group with a 100% relative remission in the DMII-OAGB group (p = 0.0265), and a 67% relative remission in the hypertension-OAGB group (p = 0.0031). Conclusions: No difference in nutritional status has been detected between patients undergoing RYGB or OAGB at the 6-Month Follow-Up. Both procedures may have significant mal-absorptive effects leading to decline in nutritional status. OAGB may be more efficacious in inducing DMII and hypertension remission. Larger prospective studies dedicated specifically to nutritional status after gastric bypass are needed to confirm the impact of different bypass procedures on nutritional status.  相似文献   
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