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951.
Raw milk is increasingly appreciated by consumers but can be contaminated by a variety of zoonotic pathogens. Therefore, preventive measures, such as on-farm hazard analysis critical control point (HACCP) programs, must be applied to protect consumers. The aim of the present study was the comparison of a multiplex real-time polymerase chain reaction (PCR) assay with a culture-based approach in an on-farm quality assurance program for the detection of Escherichia coli O157, Salmonella spp., and Listeria monocytogenes in bulk tank milk, in-line milk filters, manure, and feces. Results revealed that the real-time PCR was more sensitive in detecting E. coli O157 than the culture method in filters (48% vs. 4% positive), manure (93% vs. 7% positive) and feces (60% vs. 4% positive). The two methods were equally efficient in detecting L. monocytogenes (8% of filters), while Salmonella spp. was not detected in any sample. In conclusion, the real-time PCR, by reducing analysis time to two working days, can be proposed as a useful tool in the raw milk primary production setting as a rapid and user-friendly screening method.  相似文献   
952.
In Italy, revascularization interventions increased from 44,600 in 1996 to more than 100,000 in 2001. In particular, the occurrence of percutaneous transluminal coronary angioplasty (PTCA) increased from 239 cases per million population in 1994 to about 1300 cases per million population in 2001. This trend has caused a concomitant increase in revascularization costs, which have doubled in few years, rising from Euro 421 millions in 1996 to Euro 850 millions in 2001. In 2001, PTCA amounted to 55% of total cost of revascularizations. The aim of this study was to assess the pharmacoeconomic consequences of amlodipine besylate therapy administered in patients at high risk of restenosis after PTCA. We conducted a cost-effectiveness analysis comparing therapy with amlodipine besylate added to standard care versus standard care alone. Information on clinical outcomes was drawn from the Coronary Angioplasty Amlodipine Restenosis Study (CAPARES). Medical costs were estimated with reference to drug therapy and hospitalizations for coronary events and revascularization procedures. The study was conducted from the perspective of the Italian third party payer (National Health Service). The analysis was applied to a time horizon of 4 months. Amlodipine besylate resulted less expensive and more effective than standard care. It reduced mortality, morbidity for coronary reasons and the need of revascularization procedures. The cost per 1000 patients was estimated at Euro 1,166,000 in the placebo and Euro 950,000 in the amlodipine besylate group, resulting into a cost saving of Euro 216,000, that is 18.5% of total cost of standard care. Results are sensitive to the cost of amlodipine besylate and the cost of hospitalizations, but therapy with amlodipine besylate resulted dominant even in the most unfavorable hypothesis.  相似文献   
953.
The comet assay has been widely used to quantify DNA damage in isolated lymphocytes from subjects exposed to several environmental or occupational substances, especially for estimation of oxidative damage in the DNA, which is well-known to be induced by tobacco smoke. Passive smoking or environmental tobacco smoke (ETS) has been included among those substances that cause cancer with sufficient evidence in humans. In this study, we analyzed, by the alkaline version of comet assay, the lymphocyte DNA damage of white-collar active smokers and non- and ex-smokers exposed to ETS at the workplace. We investigated basal DNA damage, DNA oxidation by formamidopyrimidine glycosylase (Fpg), the repair capacity H2O2-induced DNA damage by kinetics studies and lymphocyte GSH levels, the major intracellular defense against exogenous oxidative stress imposed by cigarette smoking. Our results indicated high basal DNA damage with clear significant correlations with urinary nicotine and cotinine, number of cigarettes/day, and an inverse significant correlation with GSH cellular content in active smokers. Significant Fpg-sensitive sites were found in smokers (> 85%), considerably high but not significant in passive non- and ex-smokers (> 51% and 37%, respectively). The DNA repair capacity had seriously decreased in non-smokers > smokers > ex-smokers, while the same damage was repaired in a short time in never smokers.  相似文献   
954.
ABSTRACT: Despite the appearance of new treatment, dietary approach remains the mainstay of PKU therapy. The nutritional management has become complex to optimize PKU patients' growth, development and diet compliance. This paper review critically new advances and challenges that have recently focused attention on potential relevant of LCPUFA supplementation, progress in protein substitutes and new protein sources, large neutral amino acids and sapropterin. Given the functional effects, DHA is conditionally essential substrates that should be supplied with PKU diet in infancy but even beyond. An European Commission Programme is going on to establish quantitative DHA requirements in this population. Improvements in the palatability, presentation, convenience and nutritional composition of protein substitutes have helped to improve long-term compliance with PKU diet, although it can be expected for further improvement in this area. Glycomacropeptide, a new protein source, may help to support dietary compliance of PKU subject but further studies are needed to evaluate this metabolic and nutritional issues. The PKU diet is difficult to maintain in adolescence and adult life. Treatment with large neutral amino acids or sapropterin in selected cases can be helpful. However, more studies are necessary to investigate the potential role, dose, and composition of large neutral amino acids in PKU treatment and to show long-term efficacy and tolerance. Ideally treatment with sapropterin would lead to acceptable blood Phe control without dietary treatment but this is uncommon and sapropterin will usually be given in combination with dietary treatment, but clinical protocol evaluating adjustment of PKU diet and sapropterin dosage are needed.In conclusion PKU diet and the new existing treatments, that need to be optimized, may be a complete and combined strategy possibly positive impacting on the psychological, social, and neurocognitive life of PKU patients.  相似文献   
955.
Immunogenicity of influenza A (H1N1)v MF59-adjuvanted vaccine was studied in HIV-infected patients. The vaccine was effective in inducing a protective immune response in patients with a CD4 >200 cells/μL while individuals with CD4 <200 cells/μL showed lower rates of seroconversion and seroprotection. These results underscore the usefulness of immunization against influenza in HIV-infected patients, though a boosting dose of vaccine may be required in seriously immunocompromised patients.  相似文献   
956.
OBJECTIVE: To evaluate the prevalence of beta(3)-adrenergic receptor (ADRB3) Trp64Arg polymorphism and its relationship with the metabolic syndrome in severe obesity. DESIGN: Cross-sectional outpatients study. PATIENTS AND METHODS: In 265 (100 men) severely obese non-diabetic subjects and 78 (25 men) healthy volunteers, genomic DNA was isolated from peripheral leukocytes. In obese patients, plasma concentrations of leptin, lipids, glucose and insulin, the homeostasis model assessment index and blood pressure have been measured. The Trp64Arg mutation was identified with the real-time TaqMan method. RESULTS: Neither genotype distribution nor allele frequency differed between the two groups. The metabolic syndrome prevalence was 59% in obese subjects, and was higher in men than in women (65 vs 55%: P=0.03). The body mass index (BMI) was related to age tertiles (beta=0.08; P<0.001; multiple linear regression) in Trp64Arg-positive obese subjects. CONCLUSION: We confirm the high prevalence of the metabolic syndrome among severely obese subjects. ADRB3 polymorphism was significantly related to insulin resistance only in obese male subjects. Moreover, increased BMI was related to age in obese subjects with the ADRB3 polymorphism.  相似文献   
957.
958.
BACKGROUND: Hepatic dysfunction, manifested as liver enzyme elevations, occurs frequently in patients who are treated with interferon, however, data for patients with multiple sclerosis are limited.OBJECTIVE: To retrospectively assess the safety profile of interferon-beta-1a therapy with respect to liver function during clinical trials and postmarketing surveillance in the treatment of multiple sclerosis. PATIENTS AND METHODS: Adverse effects and laboratory abnormalities were analysed from six randomised, controlled clinical trials (five of which were placebo-controlled) that assessed the use of interferon-beta-1a in patients with multiple sclerosis. Treatment data were collected for 2819 patients for up to 12 months, of whom 1995 received interferon-beta-1a (337 [12%] received Avonex intramuscular therapy, and 1658 [59%] received Rebif subcutaneous therapy), and 824 (29%) received placebo. Data for 2 years were collated for 1178 patients (from two studies). Total weekly interferon doses were 22-132 microg. Postmarketing surveillance data were also analysed. RESULTS: In patients receiving interferon-beta-1a, there were significant elevations of alanine aminotransferase (ALT) levels, of all grades of severity, in up to 59% of patients at 6 months, up to 64% of patients at 12 months and up to 67% of patients at 24 months; ALT elevations were asymptomatic and dose related. More than 50% of elevations in liver enzymes occurred during the first 3 months of treatment, and more than 75% occurred during the first 6 months. Elevated enzyme levels resolved spontaneously or with dosage adjustment. Although the overall incidence of liver enzyme elevation was high during the early months of therapy, after 2 years, the proportion of patients with abnormal liver enzyme levels was 11% of those receiving Rebif 44 microg three times weekly compared with 6% of placebo-treated patients. Only 0.4% of patients discontinued interferon-beta-1a treatment because of hepatic adverse effects. Serious symptomatic interferon-related hepatic toxicity occurs, but is uncommon. Concomitant medication use was not associated with increased risk. CONCLUSION: Asymptomatic hepatic dysfunction is common in patients with multiple sclerosis who are treated with interferon-beta-1a, and is dose related. Adverse effects are mainly mild and transient, with little impact on adherence to therapy, although rare serious events can occur. Regular liver function monitoring during the first 6 months is recommended.  相似文献   
959.
The extracellular gamma-glutamyltransferase-mediated metabolism of glutathione has been implicated in prooxidant events which may have impact on cellular functions including drug resistance. This study was performed in two GGT-transfected melanoma clones to explore the hypothesis that GGT expression in tumour cells is implicated in modulation of cell behaviour under stress conditions. Our results show that GGT-overexpression in melanoma cells was associated with resistance to oxidative stress produced by prooxidant agents such as hydrogen peroxide and ascorbic acid. In GGT-overexpressing cells, ability to tolerate oxidative stress was evidenced by the presence of a moderate level of ROS and lack of DNA damage response following treatment with H(2)O(2). Cellular response to oxidative stress induced by ascorbic acid was detectable only in the clone with low GGT activity which also exhibited an increased susceptibility to apoptosis. The increased resistance of the GGT-overexpressing clone was not related to intracellular GSH content but rather to the increased expression of catalase and to a reduced efficiency of iron-mediated formation of toxic free radicals. Taken together, these findings are consistent with a contribution of GGT in the mechanisms of drug resistance, because induction of oxidative stress is a relevant event in the apoptotic response to cytotoxic agents.  相似文献   
960.
Current studies are investigating new E-cadherin gene (CDH1) mutations that may be responsible for diffuse gastric cancer susceptibility. Recently, a novel CDH1 germline variant presenting a G/A nucleotide change at cDNA position 2494 has been found in Japanese patients with familial diffuse gastric cancer. The consequent amino acid variation (Val/Met) may alter the binding activity to beta-catenin and the adhesive function of the E-cadherin protein. We have investigated its frequency in Italian cases of sporadic diffuse gastric cancer a well as in healthy controls. Peripheral blood samples were collected from consecutive patients with sporadic, diffuse gastric cancer and from healthy controls in the District of Urbino, Marche Region, Central Italy. After DNA extraction, standard techniques for molecular analyses were used to investigate the 2494 G/A germline nucleotide change in CDH1 cDNA. None of the 48 patients and 48 controls showed the G/A 2494 nucleotide change. Assuming a binomial distribution of the mutation among individuals and the absence of mutations in the 48 patients, the 95% upper bound for the underlying mutation frequency was 7.4%. The novel CDH1 nucleotide change is uncommon in Italian patients with sporadic diffuse gastric cancer. Given these results, further analyses in large population-based studies are not advisable.  相似文献   
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