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101.

Purpose  

The lipophilic cationic compound, (4-[18F]fluorophenyl)triphenylphosphonium ion (18F-FTPP) was synthesized and evaluated as a potential positron emission tomography (PET) myocardial perfusion agent.  相似文献   
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Synthetic glucocorticoids are the mainstay treatment for stimulating lung maturation in threatened preterm delivery. Animal studies suggest that in utero exposure to glucocorticoids leads to a reduction in birth size. Smaller birthweight has been associated with higher risk of many chronic diseases. Therefore, the authors undertook a systematic review of human studies examining the association between synthetic glucocorticoid treatment and birth size. Medline, EMBASE, PubMed, Cochrane, Google scholar and Institute of Life Science databases were searched for studies published between 1978 and 2009 investigating the association between synthetic glucocorticoids and birthweight, head circumference, birth length and ponderal index. All studies controlling for gestational age were examined. Seventeen studies were included in the analysis. Nine out of 17 studies reported a reduction in birthweight (range 12-332 g), five of nine a reduction of head circumference (range 0.31-1.02 cm) and two of four a reduction of 0.8 cm in birth length. Despite methodological inconsistencies and limitations that impede clear conclusions, the evidence suggests an association between in utero exposure to synthetic glucocorticoids and reduced birth size.  相似文献   
105.
Genome-wide association scans recently identified common polymorphisms, in intron 1 of FTO and 188 kb downstream MC4R, that modulate body mass index (BMI) and associate with increased risk of obesity. Although their individual contribution to obesity phenotype is modest, their combined effects and their interactions with environmental factors remained to be evaluated in large general populations from birth to adulthood. In the present study, we analyzed independent and combined effects of the FTO rs1421085 and MC4R rs17782313 risk alleles on BMI, fat mass, prevalence and incidence of obesity and subsequent type 2 diabetes (T2D) as well as their interactions with physical activity levels and gender in two European prospective population-based cohorts of 4,762 Finnish adolescents (NFBC 1986) and 3,167 French adults (D.E.S.I.R.). Compared to participants carrying neither FTO nor MC4R risk allele (20–24% of the populations), subjects with three or four risk alleles (7–10% of the populations) had a 3-fold increased susceptibility of developing obesity during childhood. In adults, their combined effects were more modest (~1.8-fold increased risk) and associated with a 1.27% increase in fat mass (P?=?0.001). Prospectively, we demonstrated that each FTO and MC4R risk allele increased obesity and T2D incidences by 24% (P?=?0.02) and 21% (P?=?0.02), respectively. However, the effect on T2D disappeared after adjustment for BMI. The Z-BMI and ponderal index of newborns homozygous for the rs1421085 C allele were 0.1 units (P?=?0.02) and 0.27 g/cm3 (P?=?0.005) higher, respectively, than in those without FTO risk allele. The MC4R rs17782313 C allele was more associated with obesity and fat mass deposition in males than in females (P?=?0.003 and P?=?0.03, respectively) and low physical activity accentuated the effect of the FTO polymorphism on BMI increase and obesity prevalence (P?=?0.008 and P?=?0.01, respectively). In European general populations, the combined effects of common polymorphisms in FTO and MC4R are therefore additive, predictive of obesity and T2D, and may be influenced by interactions with physical activity levels and gender, respectively.  相似文献   
106.

Objective

Deep NREM sleep and its hallmark EEG phenomenon slow wave activity (SWA) are under homeostatic control in adults. SWA is also locally regulated as it increases in the brain areas that have been used intensively. Moreover, in children, SWA is a marker of cortical maturation. In the present study the local properties of NREM sleep depth were evaluated using the quantitative mean frequency method. We aimed to study if age is related to NREM sleep depth in young infants. In addition, we studied if young infants have local differences in their NREM sleep.

Methods

Ambulatory over-night polysomnographies were recorded in 59 healthy and full-term infants at the age of one month. The infants were divided into two age groups (<44?weeks and ≥44?weeks) to allow maturational evaluations.

Results

The quantitative sleep depth analysis showed differences between the age groups. In addition, there were local sleep depth differences within the age groups.

Conclusions

The sleep depth change with age is most likely related to cortical maturation, whereas the local sleep depth gradients might also reflect the use-dependent properties of SWA.

Significance

The results support the idea that young infants have frontal cortical processing.  相似文献   
107.
Background:  Today, the first generations of very low birth weight (VLBW ≤ 1500 g) infants are entering adulthood but very little is known of their personality traits, associated with both psychopathological vulnerability and resilience.
Methods:  In this cohort study we compared personality traits among young adults (age range 18 to 27 years, mean 21.4, SD 2.19) with VLBW ( n  = 158) with those of term-born controls ( n  = 168) of same gender, age, and maternity hospital. The participants completed the Neo-Personality Inventory.
Results:  Of the five main traits, the VLBW participants scored significantly higher in conscientiousness (MD .1, 95% CI .0 to .3; p  < .03), agreeableness (MD .2, 95% CI .0 to .3; p  < .001), and lower in openness to experience (MD –.1, 95% CI –.2 to .0; p  < .02). In addition, the VLBW group differed from the controls with regard to facets of neuroticism (lower hostility and impulsivity, p s < .05) and extraversion (less assertiveness p  < .01). Furthermore, there were fewer undercontrolled personality profiles among the VLBW subjects ( p  < .01). All differences were independent of gender, age at assessment, parental education, individual school grade average, and maternal pre-eclampsia and smoking during pregnancy.
Conclusions:  Young adults born with VLBW showed markedly different personality traits compared with their controls. The VLBW group displayed less negative emotions, were more dutiful and cautious, and displayed more warmth in their social relationships than their term-born peers. We present two potential mechanisms underlying these findings. The first relates to parental influences and the other to evidence linking biological mechanisms associated with prematurity with personality characteristics in adulthood.  相似文献   
108.
A pH, thermal, and redox potential triple-responsive expansile nanogel system (TRN), which swells at acidic pH, temperature higher than its transition temperature, and reducing environment, has been developed. TRN quickly expands from 108 nm to over 1200 nm (in diameter), achieving more than 1000-fold size enlargement (in volume), within 2 h in a reducing environment at body temperature. Sigma-2 receptor targeting-ligand functionalized TRN can effectively target head and neck tumor, and help Pc 4 targeting mitochondria inside cancer cells to achieve enhanced photodynamic therapy efficacy.  相似文献   
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Although implantation of fetal dopamine (DA) neurons can reduce parkinsonism in patients, current methods are rudimentary, and a reliable donor cell source is lacking. We show that transplanting low doses of undifferentiated mouse embryonic stem (ES) cells into the rat striatum results in a proliferation of ES cells into fully differentiated DA neurons. ES cell-derived DA neurons caused gradual and sustained behavioral restoration of DA-mediated motor asymmetry. Behavioral recovery paralleled in vivo positron emission tomography and functional magnetic resonance imaging data demonstrating DA-mediated hemodynamic changes in the striatum and associated brain circuitry. These results demonstrate that transplanted ES cells can develop spontaneously into DA neurons. Such DA neurons can restore cerebral function and behavior in an animal model of Parkinson's disease.  相似文献   
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