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101.
The intestinal fatty-acid binding protein-2 (FABP2) gene codes a protein responsible for the absorption of long-chain fatty acids. To test whether FABP2 is a candidate gene for renal disease in patients with type 2 diabetes, a functional A54T polymorphism was genotyped in 1,042 Brazilians with type 2 diabetes. Patients were classified as having normoalbuminuria (urinary albumin excretion [UAE] <20 microg/min; n = 529), microalbuminuria (UAE 20-199 microg/min; n = 217), or proteinuria (UAE >199 microg/min; n = 160). Patients with end-stage renal disease (ESRD) (n = 136) were also included. The prevalence of the TT genotype was higher in patients with renal involvement compared with those with normoalbuminuria (odds ratio [95% CI] 2.4 [1.1-5.4]) following adjustment for type 2 diabetes duration, BMI, hypertension, A1C, and cholesterol levels. The risk was similar considering different stages of renal involvement. In a second independent patient sample (483 type 2 diabetic Caucasians residing in Massachusetts), a significant association was also observed between the TT genotype and proteinuria or ESRD (2.7 [1.0-7.3]; P = 0.048). This study thus provides evidence that FABP2 confers susceptibility to renal disease in type 2 diabetic patients.  相似文献   
102.
The objective of this study was to determine the effects of body position (supine vs prone) on cardiorespiratory activity during quiet and active sleep in growing low birth weight (LBW) infants. The effect of postconceptional age on cardiorespiratory activity in the two positions was also evaluated. Fifty-one healthy, growing, appropriate for gestational age LBW infants (795-1600 g), ranging from 26-37 weeks in gestational age, were evaluated. All subjects were enrolled in an ongoing study of the effects of quality of dietary energy on the rate and composition of weight gain. Infants were randomly assigned to the supine or prone position for the first 3 h of the 6-h studies; the position was reversed for the second 3 h. Continuous recordings of cardiorespiratory activity were performed along with simultaneous minute by minute assignment of behavioral sleep state. Measurements of heart rate (HR), heart period variability (RR-SD), respiratory rate (f), and respiratory variability (fSD) were made each minute. Low birth weight infants had higher HR and f and lower RR-SD and fSD in the prone position compared to the supine position, during both quiet and active sleep. With increasing postconceptional age, positional differences in HR increased during quiet sleep and differences in RR-SD increased during both sleep states. These data demonstrate systematic differences in cardiorespiratory control related to body position during sleep. We speculate that such positional differences are due to variations in autonomic control, and may, in turn, contribute to variations in susceptibility to sudden infant death syndrome.  相似文献   
103.
Vascular contraction is an important determinant of the peripheral vascular resistance and blood pressure. The mechanisms underlying vascular smooth muscle (VSM) contraction and the pathological changes that occur in hypertension have been the subject of numerous studies and interpretations. Activation of VSM by vasoconstrictor stimuli at the cell surface causes an increase in [Ca(2+)](i), Ca(2+)-dependent activation of myosin light chain (MLC) kinase, MLC phosphorylation, actin-myosin interaction and VSM contraction. Additional signaling pathways involving Rho-kinase and protein kinase C (PKC) may increase the myofilament force sensitivity to [Ca(2+)](i) and MLC phosphorylation, and thereby maintain vascular contraction. PKC is a particularly intriguing protein kinase as it comprises a family of Ca(2+)-dependent and Ca(2+)-independent isoforms, which have different tissue and subcellular distribution, and undergo differential translocation during cell activation. PKC translocation to the cell surface may trigger a cascade of protein kinases, such as mitogen-activated protein kinase (MAPK) and MAPK kinase (MEK) that ultimately interact with the contractile myofilaments and cause VSM contraction. Also, PKC translocation to the nucleus may promote VSM growth and proliferation. Increased PKC expression and activity have been identified in several forms of hypertension. The subcellular location of PKC may determine the state of VSM activity, and may be useful in the diagnosis/prognosis of hypertension. Vascular PKC isoforms may represent specific targets for modulation of VSM hyperactivity, and isoform-specific PKC inhibitors may be useful in treatment of Ca(2+) antagonist-resistant forms of hypertension.  相似文献   
104.
Previous studies reported that dairy foods are associated with higher areal bone mineral density (BMD) in older adults. However, data on bone strength and bone microarchitecture are lacking. We determined the association of dairy food intake (milk, yogurt, cheese, milk + yogurt, and milk + yogurt + cheese, servings/week) with high resolution peripheral quantitative computed tomography (HR-pQCT) measures of bone (failure load, cortical BMD, cortical thickness, trabecular BMD, and trabecular number). This cross-sectional study included participants with diet from a food frequency questionnaire (in 2005–2008 and/or 1998–2001) and measurements of cortical and trabecular BMD and microarchitecture at the distal tibia and radius (from HR-pQCT in 2012–2015). Sex-specific multivariable linear regression estimated the association of dairy food intake (energy adjusted) with each bone measure adjusting for covariates. Mean age was 64 (SD 8) years and total milk + yogurt + cheese intake was 10.0 (SD 6.6) and 10.6 (6.4) servings/week in men and women, respectively. No significant associations were observed for any of the dairy foods and bone microarchitecture measures except for cheese intake, which was inversely associated with cortical BMD at the radius (p = 0.001) and tibia (p = 0.002) in women alone. In this cohort of primarily healthy older men and women, dairy intake was not associated with bone microarchitecture. The findings related to cheese intake and bone microarchitecture in women warrant further investigation.  相似文献   
105.
106.
We evaluated the feasibility of using Computrition to design and implement a low vs. typical sodium meal plan intervention for older adults. Dietitians used Computrition to design a 7-day meal plan with three caloric levels (≤1750, 2000, ≥2250 kcals/day) and two sodium densities (low = 0.9 mg/kcal; n = 11 or typical = 2 mg/kcal; n = 9). Feasibility was determined by post-hoc definitions of effectiveness, sodium compliance, palatability of diet, sustainability, and safety. Given the low number of participants in one of the three calorie groups, the higher calorie groups were combined. Thus, comparisons are between low vs. typical meal plans at two calorie levels (≤1750 or ≥2000 kcals/day). Overall, regardless of the calorie group, the meal plans created with Computrition were effective in reaching the targeted sodium density and were safe for participants. Furthermore, individuals appeared to be equally compliant and reported similar palatability across meal plans. However, one of the three criteria for the sustainability definition was not met. In conclusion, we successfully used Computrition to design low and typical sodium meal plans that were effective, compliable, and safe. Future studies of older adults in similar settings should focus on improving the palatability of the meal plans and scaling this protocol to larger studies in older adults.  相似文献   
107.
Increased platelet aggregation contributes to vascular risk. D-003, a mixture of high molecular weight sugarcane wax acids, has shown antiplatelet effects in experimental models and healthy volunteers. This randomised, double-blinded, placebo-controlled study investigated the effects of titrated doses of D-003 (5-20 mg/d) on platelet aggregation in hypercholesterolemic patients. After a 4-week baseline phase, 56 patients were randomised to D-003 5 mg/d or placebo. The doses were doubled every 15 days if arachidonic acid (AA)-induced platelet aggregation was not inhibited at least by 15%. AA (0.75 and 1.5 mmol/L) and collagen (1 microg/mL)-induced platelet aggregation, laboratory and physical safety indicators were assessed at baseline and every 15 days thereafter, when adverse events (AE) were also reported. No significant change of platelet aggregation was found in the placebo group. After 15, 30 and 45 on therapy, D-003 reduced platelet aggregation induced with both AA 0.75 mmol/L (18.1%, 19.0% and 30.3%, respectively) and AA 1.5 mmol/L (17.0%, 16.3% and 22.5%, respectively), and also collagen-induced platelet aggregation (26.6%, 20.8% and 29.4%) (p < 0.01 at days 15 and 30 versus placebo, p < 0.0001 at study completion). The mean inhibition of platelet aggregation with D-003 at day 15, at which all patients had received the lowest dose, was over 15%. Nineteen out of 28 D-003 randomised patients (67.9%) required dose titration to achieve such goal. At trial completion, the mean estimated dose was 11.6 mg/d. D-003 lowered low-density lipoprotein (22.0 %), total cholesterol (14.7%) and raised high-density lipoprotein-cholesterol (10.9%) (p < 0.0001 versus placebo). Six patients (2 placebo, 4 D-003) withdrew from the trial, none due to AE. D-003 did not modify the safety indicators with respect to placebo. Four patients (2 placebo, 2 D-003-treated) reported AE: pruritus and increased blood pressure (2 placebo) and rash and polyphagla (2 D-003). In conclusion, D-003 (5-20 mg/d) given as doses titrated every 15 days (5-20 mg/d) inhibited AA- and collagen-induced platelet aggregation in hypercholesterolemic patients and was well tolerated.  相似文献   
108.
We have demonstrated that vaccination of turkeys with an unformulated DNA vaccine induces significant protection against Chlamydophila (Cp.) psittaci infections. Nevertheless, the immunogenicity of the DNA vaccine can still be improved by increasing translation and transfection efficiency. Therefore, the ompA codon was adapted to the codon usage in birds, resulting in pcDNA1/MOMPopt. To increase gene transfer, polyplexes of pcDNA1/MOMPopt–EGFP with different cationic polymers, such as linear and branched polyethyleneimine (lPEI and brPEI) and starburst PAMAM dendrimers, and lipoplexes with cationic DOTAP/DOPE liposomes were created. Transfection of lPEI and brPEI polyplexes with an N/P ratio of 8 resulted in the highest transfection efficiencies, but lPEI polyplexes were completely destroyed following nebulisation. Secondly, we examined the capacity of nebulised or intramuscularly (IM) administered brPEI-pcDNA1/MOMPopt to induce a significant protective immune response in SPF turkeys experimentally infected with 108 TCID50 of a virulent Cp. psittaci strain. Results were compared to IM administration of naked plasmid DNA and to results of non-vaccinated animals. Intramuscular administration of brPEI-pcDNA1/MOMPopt increased the immunogenicity of the Cp. psittaci DNA vaccine as compared to IM administration of pcDNA1/MOMPopt or aerosol delivery of brPEI-pcDNA1/MOMPopt. Improved immunogenicity was correlated with increased protection. Vaccinated groups were significantly protected against Cp. psittaci challenge.  相似文献   
109.
The World Anti-Doping Agency (WADA) prohibits athletes from using recombinant growth hormone (GH). The validated method used in antidoping laboratories for the direct detection of exogenous GH in serum requires two immunoluminometric assays (ILMAs): The first mainly measures the concentration of the full-length (22 kDa) form of GH (recGH), and the second measures concentrations of multiple GH fragments produced by the pituitary gland (22 kDa, 20 kDa and other forms) (pitGH). The tube-by-tube analysis is laborious. A recent development opened new possibilities to simplify the detection of recGH in serum: multiplexed immunoassays that detect multiple targets in a single well of a 96-well plate using an ELISA-like procedure with high sensitivity. Our aim was to evaluate this technology by developing a customized assay for GH detection. One pair of antibodies with specificities similar to those of the recGH assay and one pair of antibodies compatible with pitGH detection were selected for a single duplex assay. Forty-eight serum samples (negative athlete samples and positive samples following GH administration) were analyzed using the two methods. The microplate duplex assay discriminated between the negative athlete samples and the positive controls, although the rec/pit ratios from the duplex assay were lower than those obtained with the ILMAs. This new assay would offer a modern alternative to ILMAs, with fewer analytical steps and a smaller sample volume. However, an adaptation of the decision limits seems mandatory.  相似文献   
110.

Background

Micronutrient deficiency is a global health burden, especially among developing countries. The present cross‐sectional study aimed to determine the prevalence of vitamin B12 deficiency in healthy Indian school‐going adolescents, based on area of residence, sex and body mass index (BMI) . Furthermore, the relationship of serum B12 concentration with dietary vitamin B12 intake and anthropometric indices was assessed among adolescents from rural and urban India.

Methods

A total of 2403 school‐going adolescents (11–17 years) from National Capital Region and rural areas of Haryana, India were selected. Serum B12 concentrations were estimated using an electrochemiluminescence immunoassay. Dietary assessments were conducted on 65% of total participants (n  = 1556) by two 24‐h diet recalls.

Results

The prevalence of vitamin B12 deficiency in the total study population was 32.4% (rural: 43.9% versus urban: 30.1%, P  < 0.001; male: 34.4% versus female: 31.0%, P  < 0.05; normal weight: 28.1%, versus overweight: 39.8%, versus obese: 51.2%, P  < 0.001). More than half (51.2%) of obese adolescents were vitamin B12 deficient. On multiple linear regression analysis, serum B12 in rural adolescents was associated with age (β = ?0.12, P  < 0.05). Among urban adolescents, serum B12 was associated with BMI (β = ?0.08, P  < 0.05) and adjusted dietary vitamin B12 intake (β = 0.14, P  < 0.001). Serum vitamin B12 levels were found to be lower in rural females (β = ?0.12, P  = 0.030) and urban males (β: 0.11, P  < 0.001) compared to their respective contemporaries.

Conclusions

Vitamin B12 deficiency was higher among rural school‐going adolescents. Boys had a higher B12 deficiency than girls. Inverse associations of serum B12 with adiposity indices were observed. Serum B12 levels were positively associated with dietary vitamin B12 intake.
  相似文献   
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