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101.
Purpose Insulin resistance, characterised by an insulin-stimulated glucose transport defect, is an important feature of the pre-diabetic state that has been observed in numerous pathological disorders. The purpose of this study was to assess variations in glucose transport in rats using 125I-6-deoxy-6-iodo-D-glucose (6DIG), a new tracer of glucose transport proposed as an imaging tool to assess insulin resistance in vivo. Methods Two protocols were performed, a hyperinsulinaemic–euglycaemic clamp and a normoinsulinaemic–normoglycaemic protocol, in awake control and insulin-resistant fructose-fed rats. The tracer was injected at steady state, and activity in 11 tissues and the blood was assessed ex vivo at several time points. A multicompartmental mathematical model was developed to obtain fractional transfer coefficients of 6DIG from the blood to the organs. Results Insulin sensitivity of fructose-fed rats, estimated by the glucose infusion rate, was reduced by 40% compared with control rats. At steady state, 6DIG uptake was significantly stimulated by insulin in insulin-sensitive tissues of control rats (basal versus insulin: diaphragm, p < 0.01; muscle, p < 0.05; heart, p < 0.001), whereas insulin did not stimulate 6DIG uptake in insulin-resistant fructose-fed rats. Moreover, in these tissues, the fractional transfer coefficients of entrance were significantly increased with insulin in control rats (basal vs insulin: diaphragm, p < 0.001; muscle, p < 0.001; heart, p < 0.01) whereas no significant changes were observed in fructose-fed rats. Conclusion This study sets the stage for the future use of 6DIG as a non-invasive means for the evaluation of insulin resistance by nuclear imaging.  相似文献   
102.
Strokes are the main neurological manifestation of antiphospholipid syndrome. Other clinical presentations are possible and may mimic classic symptoms of multiple sclerosis (MS). A 46-year-old woman, with a history of two miscarriages, presented four subacute neurological episodes (optic neuritis, right facial paralysis, paraparesis of the thigh, and right brachial monoparesis). Using McDonald criteria, the diagnosis of multiple sclerosis was retained. Because of the occurrence of thrombocytopenia during a final relapse, we reconsidered the diagnosis of MS. Search for antiphospholipid antibodies was positive. All clinical manifestations and complementary tests were compatible with the diagnosis of antiphospholipid syndrome associated with multiple sclerosis. Given the great similarity of clinical, radiological and biological findings in the two diseases, non-thrombotic neurological manifestations of antiphospholipid syndrome can be difficult to distinguish from MS associated with antiphospholipid syndrome.  相似文献   
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Diets high in vegetables and fruits have been suggested to be inversely associated with risk of gastric cancer. However, the evidence of the effect of variety of consumption is limited. We therefore investigated whether consumption of a variety of vegetables and fruit is associated with gastric and esophageal cancer in the European Prospective Investigation into Cancer and Nutrition study. Data on food consumption and follow-up on cancer incidence were available for 452,269 participants from 10 European countries. After a mean follow-up of 8.4 years, 475 cases of gastric and esophageal adenocarcinomas (180 noncardia, 185 cardia, gastric esophageal junction and esophagus, 110 not specified) and 98 esophageal squamous cell carcinomas were observed. Diet Diversity Scores were used to quantify the variety in vegetable and fruit consumption. We used multivariable Cox proportional hazard models to calculate risk ratios. Independent from quantity of consumption, variety in the consumption of vegetables and fruit combined and of fruit consumption alone were statistically significantly inversely associated with the risk of esophageal squamous cell carcinoma (continuous hazard ratio per 2 products increment 0.88; 95% CI 0.79-0.97 and 0.76; 95% CI 0.62-0.94, respectively) with the latter particularly seen in ever smokers. Variety in vegetable and/or fruit consumption was not associated with risk of gastric and esophageal adenocarcinomas. Independent from quantity of consumption, more variety in vegetable and fruit consumption combined and in fruit consumption alone may decrease the risk of esophageal squamous cell carcinoma. However, residual confounding by lifestyle factors cannot be excluded.  相似文献   
105.
Several methods of liver tumor ablation have been investigated, and these include the novel technique of electrolysis. Electrolysis is slower than other forms of ablative therapy. This study determined methods of increasing the ablative effect of electrolysis. Domestic white pigs were divided. One group received electrolysis using two electrode catheters, and in the other group a concurrent intermittent Pringle maneuver was performed to induce intermittent ischemia. The effect of two electrode catheters versus a single electrode catheter was compared, and the effect of the Pringle maneuver versus no Pringle was examined with two electrode catheters. The livers were harvested, and the volume of each lesion was calculated. There was a linear relationship between the volume of hepatic necrosis and the electrolytic dose in (p <.005) in both the single-electrode-catheter and two-electrode-catheter groups. Comparison between the single- and multiple-electrode groups showed a highly significant difference in the dose response (p <.0000002) when more than one electrode was used. Use of the Pringle maneuver during electrolysis produced larger volumes of hepatic necrosis over all doses when using two electrode catheters. Rates of necrosis were 3.8 cm(3)/100 C for a single electrode catheter, 5.46 cm(3)/100 C for two electrode catheters without Pringle, and 6.17 cm(3)/100 C for electrolysis with two electrode catheters coupled with intermittent Pringle maneuver. Thus, electrolysis was both reliable and predictable in producing hepatic necrosis in a dose-dependent manner. The time delay in achieving tumor ablation via electrolysis can be overcome by using two electrodes combined with the Pringle maneuver to increase the volume of the lesion produced.  相似文献   
106.
The aim of this study was to compare the epidemiology of rheumatoid arthritis (RA) in North Africa to that of Western countries. We have enrolled in a cross-sectional study all consecutive patients presenting with the diagnosis of RA according to the 1987 ACR criteria, and during a 5-month period, patients were included in 11 centers across northern Algeria. Demographics, clinical data, and health assessment questionnaires (HAQ) were collected for each patient. We have estimated means, standard deviations, and 95 % confidence intervals for all parameters. Of the 249 patients (213 females and 36 males) enrolled in the study, 10 (4 %) had juvenile onset of the disease. The mean age was 50.1 ± 14.5 years, and the mean duration of RA was 8.4 ± 7.8 years. In terms of comorbidities, 18.9 % of patients reported hypertension and 5.2 % had diabetes. The mean DAS28 at inclusion was 4.3 (95 % CI 4.1–4.5); 14.0 % were in remission (DAS28 ≤ 2.6). The mean HAQ score was 0.81 ± 0.82. Rheumatoid factor was positive in 78.5 % of cases, and anti-citrullinated protein/peptide antibodies, when measured, was positive in 69.0 % of cases. Seronegative patients were older and had a relatively less severe disease. For treatment, 89.7 % of patients were taking disease-modifying anti-rheumatic drugs and only 4 % were taking biologics (rituximab); 90.8 % of patients were taking glucocorticoids, and none of the patients satisfied the recommended calcium intake guidelines. RA in Algeria is more common in women. Compared to reports from Western countries, RA in Algeria appears to be less aggressive, with more dominant seronegative oligoarthritis forms. The remission rate is comparable to that of Western populations.  相似文献   
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109.
Folate plays an important role in the synthesis and methylation of DNA as a cofactor in one-carbon metabolism. Inadequate folate intake has been linked to adverse health events. However, comparable information on dietary folate intake across European countries has never been reported. The objective of the present study was to describe the dietary folate intake and its food sources in ten countries in the European Prospective Investigation into Cancer and Nutrition (EPIC) study. A cross-sectional analysis was conducted in 36?034 participants (aged 35-74 years) who completed a single 24?h dietary recall using a computerised interview software program, EPIC-Soft? (International Agency for Research on Cancer, Lyon). Dietary folate intake was estimated using the standardised EPIC Nutrient DataBase, adjusted for age, energy intake, weight and height and weighted by season and day of recall. Adjusted mean dietary folate intake in most centres ranged from 250 to 350?μg/d in men and 200 to 300?μg/d in women. Folate intake tended to be lower among current smokers and heavier alcohol drinkers and to increase with educational level, especially in women. Supplement users (any types) were likely to report higher dietary folate intake in most centres. Vegetables, cereals and fruits, nuts and seeds were the main contributors to folate intake. Nonetheless, the type and pattern of consumption of these main food items varied across the centres. These first comparisons of standardised dietary folate intakes across different European populations show moderate regional differences (except the UK health conscious group), and variation by sex, educational level, smoking and alcohol-drinking status, and supplement use.  相似文献   
110.
Epidemiological studies suggest health-protective effects of flavan-3-ols and their derived compounds on chronic diseases. The present study aimed to estimate dietary flavan-3-ol, proanthocyanidin (PA) and theaflavin intakes, their food sources and potential determinants in the European Prospective Investigation into Cancer and Nutrition (EPIC) calibration cohort. Dietary data were collected using a standardised 24?h dietary recall software administered to 36?037 subjects aged 35-74 years. Dietary data were linked with a flavanoid food composition database compiled from the latest US Department of Agriculture and Phenol-Explorer databases and expanded to include recipes, estimations and retention factors. Total flavan-3-ol intake was the highest in UK Health-conscious men (453·6?mg/d) and women of UK General population (377·6?mg/d), while the intake was the lowest in Greece (men: 160·5?mg/d; women: 124·8?mg/d). Monomer intake was the highest in UK General population (men: 213·5?mg/d; women: 178·6?mg/d) and the lowest in Greece (men: 26·6?mg/d in men; women: 20·7?mg/d). Theaflavin intake was the highest in UK General population (men: 29·3?mg/d; women: 25·3?mg/d) and close to zero in Greece and Spain. PA intake was the highest in Asturias (men: 455·2?mg/d) and San Sebastian (women: 253?mg/d), while being the lowest in Greece (men: 134·6?mg/d; women: 101·0?mg/d). Except for the UK, non-citrus fruits (apples/pears) were the highest contributors to the total flavan-3-ol intake. Tea was the main contributor of total flavan-3-ols in the UK. Flavan-3-ol, PA and theaflavin intakes were significantly different among all assessed groups. This study showed heterogeneity in flavan-3-ol, PA and theaflavin intake throughout the EPIC countries.  相似文献   
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