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991.
BackgroundLong-term cardiovascular health effects of marijuana are understudied. Future cardiovascular disease is often indicated by subclinical atherosclerosis for which carotid intima-media thickness is an established parameter.MethodsUsing the data from the Coronary Artery Risk Development in Young Adults (CARDIA) study, a cohort of 5115 Black and white women and men at Year 20 visit, we studied the association between carotid intima-media thickness in midlife and lifetime exposure to marijuana (1 marijuana year = 365 days of use) and tobacco smoking (1 pack-year = 20 cigarettes/day for 365 days). We measured carotid intima-media thickness by ultrasound and defined high carotid intima-media thickness at the threshold of the 75th percentile of all examined participants. We fit logistic regression models stratified by tobacco smoking exposure, adjusting for demographics, cardiovascular risk factors, and other drug exposures.ResultsData was complete for 3257 participants; 2722 (84%) reported ever marijuana use; 374 (11%) were current users; 1539 (47%) reported ever tobacco smoking; 610 (19%) were current smokers. Multivariable adjusted models showed no association between cumulative marijuana exposure and high carotid intima-media thickness in never or ever tobacco smokers, odds ratio (OR) 0.87 (95% confidence interval [CI]: 0.63-1.21) at 1 marijuana-year among never smokers and OR 1.11 (95% CI: 0.85-1.45) among ever tobacco smokers. Cumulative exposure to tobacco was strongly associated with high carotid intima-media thickness, OR 1.88 (95%CI: 1.20-2.94) for 20 pack-years of exposure.ConclusionsThis study adds to the growing body of evidence that there might be no association between the average population level of marijuana use and subclinical atherosclerosis.  相似文献   
992.
Prevalence of fatty liver in Japanese children and relationship to obesity   总被引:32,自引:0,他引:32  
The prevalence of fatty liver in children is unknown and its relationship to obesity is poorly defined. The present study of 810 northern Japanese children (4–12 years old) determined the prevalence of fatty liver in the pediatric population and its relationship to obesity. Diagnosis of fatty liver was based on established real-time ultrasonographic criteria. The overall prevalence of fatty liver was 2.6% and was higher for boys (3.4%) than for girls (1.8%), although not statistically significant (P=0.15). Fatty liver was found in children as young as 6 years of age. There was no significant association between the prevalence of fatty liver and height (physical growth). There was a strong positive correlation between fatty liver prevalence and established obesity indices: Rohrer's index-2 linear trend =59.2,P<0.0001; body mass index-2 linear trend =91.6,P<0.0001; and age-gender-adjusted Japanese standard index of weight for height-2 linear trend =93.2,P<0.0001. However, direct measurement of abdominal subcutaneous fat thickness by ultrasonography was the best predictor of fatty liver: 2 linear trend =159,P<0.0001. These results indicate that fatty liver may develop very early in life, and there is a direct relationship between degree of obesity and fatty liver in children.  相似文献   
993.
994.
Aims/hypothesis Pancreatic polypeptide (PP) is produced by the F-cells of the pancreas, and its plasma concentration has been used as a marker of parasympathetic activity. Recent work in rodents suggests that there is both sympathetic and parasympathetic innervation of white adipose tissue and that parasympathetic activity is anabolic resulting in lipid accumulation. We have examined whether in humans increased PP levels are associated with increased intra-abdominal fat (IAF), and thereby insulin resistance. Materials and methods We measured PP levels in 177 non-diabetic subjects (75 male/102 female; age 32–75 years) 3 min after an i.v. glucose bolus during a frequently sampled intravenous glucose tolerance test. IAF and s.c. fat (SCF) areas were measured by CT scan. The insulin sensitivity index (S I) was quantified using Bergman’s minimal model. Results PP levels were higher in men than in women (96.2 ± 72.2 vs 76.1 ± 55.0 pg/ml, mean ± SD, p = 0.037), as was IAF area (124.7 ± 67.4 vs 83.0 ± 57.7 cm2, p < 0.001). While PP levels were significantly associated with IAF (r = 0.16, p = 0.031), WHR (r = 0.30, p < 0.001) and age (r = 0.37, p < 0.01), they were not associated with SCF (r = 0.02, p = 0.829). The association between PP and IAF was not independent of age and/or sex. S I was negatively associated with PP levels (r = −0.17, p = 0.026) and IAF area (r = −0.65, p < 0.001). The association between S I and PP disappeared after adjusting for IAF area, indicating that S I was not a major determinant of PP levels. Conclusions/interpretation In humans, age and sex may modulate the association between plasma PP level and IAF area, suggesting that they may be determinants of parasympathetic activity and thus IAF accumulation.  相似文献   
995.

Objective

Carotid intima–media thickness (IMT) is a noninvasive measurement of early atherosclerosis. Most IMT studies have involved populations with low rates of racial blending. The aim of the present article is to describe IMT value distributions and analyze the influence of sex and race on IMT values in a large Brazilian sample, a setting with a high rate of racial admixture.

Methods

The Brazilian Longitudinal Study of Adult Health (ELSA-Brasil) is a multicenter cohort of 15,105 adult (aged 35–74 years) civil servants in six Brazilian cities. Baseline assessment included IMT measurements in both common carotid arteries. Race was self-reported. We studied the association between sex and race with IMT values using multiple linear regression models. We conducted analyses in all and low-risk individuals, defined as those without classical cardiovascular risk factors.

Results

We analyzed complete IMT data from 10,405 ELSA-Brasil participants. We present nomograms by age for all and low-risk individuals, stratified by sex and race. We found that men had significantly higher maximal IMT values compared with women (β = 0.058; P < 0.001). This association remained for low-risk individuals (β = 0.027; P = 0.001). In addition, Brown and White individuals had lower maximal IMT values compared with Black individuals for all (β = −0.034 and β = −0.054, respectively; P < 0.001) and low-risk individuals (β = −0.027; P = 0.013 and β = −0.035; P < 0.001, respectively).

Conclusion

We found significantly higher IMT values in men. We found significantly higher IMT values in Black individuals than White and Brown individuals. These results persisted when analyses were restricted to low-risk individuals.  相似文献   
996.
Among cystic fibrosis (CF) centers, usual doses of enteric coated (EC) pancreatic enzymes vary from one to six capsules per meal based upon arbitrary criteria for stool and growth patterns. Large doses of non-EC enzymes are associated with increased serum urate (SU) and urinary uric acid (UUA) but data are unavailable for EC enzymes. This study compared the effectiveness and safety of a relatively large dose (patient's usual dose) versus a small dose (1/4 usual dose) of EC enzymes in nine nourished children with CF, regarding decreasing fecal fat and stool nitrogen losses and maintaining normal SU and UUA concentrations. A crossover study design randomly assigned large or small doses to two consecutive 7 day treatment periods within each child. Large doses of EC enzymes reduced steatorrhea and increased SU and UUA. SU was normal with both treatments and UUA was normal, i.e., 17 of 18 values were between the 10th and 95th percentiles for healthy children eating a normal diet. When fat excretion was greater than 10% with small doses of EC enzymes, large doses resulted in reduced fat excretion and normal UUA. These data suggest that large doses of EC enzymes reduce steatorrhea and are safe in patients who have malabsorbtion with small doses.  相似文献   
997.

Objective

Regular physical exercise within structured lifestyle programs may improve weight status and minimize metabolic risk factors in childhood obesity. The aim of this study was to evaluate the effect of the one-year combined physical exercise/lifestyle program KLAKS on anthropometric and metabolic parameters and glycemic control in childhood obesity.

Materials and Methods

142 overweight/obese (BMI > 90th percentile) candidates (7–18 years) were enrolled, 115 participants completed the program. Anthropometrics and biochemical parameters were obtained at beginning and completion. An oral glucose tolerance test (OGTT) was performed in a subgroup of participants. Course of glucose and insulin levels within OGTT was correlated with several parameters and is reported here for those who completed the program.

Results

The mean standard deviation scores (SDS) decreased significantly for BMI, waist circumference, waist-to-height ratio (WHtR) and percentage body fat (all p ≤ 0.01). Improved metabolic risk markers included mean glucose levels within an OGTT at follow-up compared to baseline (p < 0.0001) and HbA1c (p = 0.05) as well as indications of improvement for gamma-glutamyl-transferase and free fatty acids.

Conclusions

The one-year combined exercise/lifestyle program KLAKS significantly improves markers of obesity and glycemic control. Impaired cardiometabolic risk markers, even subclinical, are also favorably influenced by program participation.  相似文献   
998.
Cirrhotic patients are predisposed to develop spontaneous bacteremias and/or peritonitis, mainly caused by enteric bacteria. The aim of this study was to investigate if bacterial translocation, which is the passage of bacteria from the intestinal lumen to regional lymph nodes and/or the systemic circulation, is increased in a rat model of cirrhosis. Rats were studied after 12–16 weeks of CCl4 inhalation, when samples of mesenteric lymph nodes, blood, liver, and spleen for standard bacteriologic cultures and a fragment of colon and liver for histology were obtained. Immunostaining of the cecum was performed using a polyclonal anti-Escherichia coli antibody. A significantly greater proportion of rats with cirrhosis and ascites (5 of 9; 56%) had positive mesenteric lymph node cultures compared with cirrhotics without ascites (0 of 9) and normal controls (0 of 12) (P < 0.01). In one cirrhotic rat, E. coli was isolated from both mesenteric lymph nodes and ascites. Rats with cirrhosis and ascites had significantly greater cecal submucosal edema and inflammation than rats with no ascites and controls. Immunoreactivity with E. coli was present in the cecal wall in 3 of 5 animals with E. coli translocation to mesenteric lymph nodes. In cirrhotic rats, bacterial translocation is increased after the development of ascites and may be a major factor in the development of spontaneous infections in cirrhosis.  相似文献   
999.
Summary The relationships between physical activity, obesity, fat distribution and glucose tolerance were examined in the Pima Indians who have the highest documented incidence of non-insulin-dependent diabetes. Fasting and 2-h post-load plasma glucose concentrations, body mass index, and waist-to-thigh circumference ratios were determined in 1054 subjects aged 15–59 years. Current (during the most recent calendar year) and historical (over a lifetime) leisure and occupational physical activity were determined by questionnaire. Current physical activity was inversely correlated with fasting and 2-h plasma glucose concentrations, body mass index and waist-to-thigh ratios for most sex-age groups even when diabetic subjects were excluded. Controlled for age, obesity and fat distribution, activity remained significantly associated with 2-h plasma glucose concentrations in males. In subjects aged 37–59 years, individuals with diabetes compared to those without reported significantly less leisure physical activity during the teenage years (median hours per week of activity, 9.1 vs 13.2 for men; 1.0 vs 2.2 for women). Controlled for body mass index, sex, age and waist-to-thigh ratio, subjects who reported low levels of historical leisure physical activity had a higher rate of diabetes than those who were more active. In conclusion, current physical activity was inversely related to glucose intolerance, obesity and central distribution of fat, particularly in males. Subjects with diabetes were currently less active and reported less historical physical activity than non-diabetic subjects. These findings suggest that activity may protect against the development of non-insulin-dependent diabetes both directly and through an influence on obesity and fat distribution.  相似文献   
1000.
郭春霞 《中国基层医药》2014,(10):1470-1472
目的:探讨脂肪肝患者血液指标的检测意义。方法选取122例脂肪肝患者为观察组与131例同期入院非脂肪肝患者为对照组,两组患者均给予血常规、血脂、肝功能等血液指标检查,比较两组患者各种血液指标之间的差异,统计肝功能指标与血脂指标的相关性。结果观察组血常规指标WBC、LYM、EO、RBC、HCT、HGB、MPV、大型血小板比率( P-LCR)显著高于对照组( t =10.694、3.584、5.427、18.65、22.857、23.014、4.217、4.684,均P<0.05),PLT显著低于对照组(t=5.631,P<0.05);观察组TG、TC、LDL-C、AST、ALT显著高于对照组(t=7.01、8.45、7.26、13.62、11.98,均P<0.05),而观察组HDL-C显著低于对照组(t=4.13,P<0.05);ALT与TC、TG呈正相关(OR=1.762,P<0.05),与HDL-C呈负相关(OR=0.745,P<0.05);AST与ALT、TC呈正相关(OR=3.678,P<0.05),ALT与AST、HDL-C、TG存在较好的线性分布关系。结论脂肪肝与非脂肪肝患者的血液指标存在显著差异,肝功能的指标与血脂指标之间的关系密切,降低血脂的含量有助于改善肝功能,为脂肪肝临床诊断与指导治疗提供依据。  相似文献   
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