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91.
INTRODUCTION: The loss of heterozygosity (LOH) of 16q is a structural change detected in about 20-30% of Wilms' tumour cases. Aberrations which result in deletion of 16q are also found in breast cancer, prostate cancer and liver cancer, where they are connected with a worse prognosis. The hypothesis of a bad prognosis in nephroblastomas with LOH 16q was first formulated by scientists from NWTS (National Wilms Tumor Study) on the basis of 232 cases of Wilms' tumour. However, SIOP studies (International Society of Paediatric Oncology) which included 28 cases of Wilms' tumour, did not show any clinico-pathological correlations with LOH 16q. Therefore, we aimed to evaluate the importance of LOH 16q in relation to clinico-pathological factors in a group of children, treated according to the SIOP criteria. AIMS: The aim of this work was to evaluate the frequency of LOH 16q in sporadic unilateral Wilms' tumour and to study the relationship between LOH 16q and selected patho-clinical parameters. The study comprised 66 children (31 girls and 35 boys) aged from 2 days to 13 years. METHODS: LOH 16q was studied by the examination of polymorphism of marker sequences in the region 16q24. DNA was isolated from paraffin sections of tissue for routine microscopic examination by the microdissection method. The method of study involved the amplification of polymorphic sequences from the 16q24 region by polymerase chain reaction (PCR) and separation of the products of amplification by polyacrylamide gel electrophoresis. The results were the subject of statistical analysis in relation to gender, age of child at first diagnosis, stage of clinical advancement and histological type of tumour. The connection between LOH 16q and recurrences, metastases and death, and failure free survival and absolute survival of children followed-up for over 24 months after nephrectomy were studied. RESULTS: The study revealed a lack of correlation between LOH 16q and gender, however LOH 16q was more frequent in children with Wilms' tumour aged >24 months, P<0.05. Also, LOH 16q was more frequent in tumours classified as clinical stage (CS) II or III than in CS I, P<0.05, but there were no differences in the occurrence of LOH 16q in tumours classified as CS II and CS III. We have found no correlation between LOH 16q and the histological type of tumour. However, LOH 16q has been found three times as frequently in tumours from children who died than in tumours of children who survived, P<0.0024.  相似文献   
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The aim of the study was to determine whether human fetuses show ACTH response to stress stimuli, to define the gestational age from which these reactions may be present and to analyze the relationship between hormone concentrations and their changes, both in fetuses and in pregnant women. The study included 81 intrauterine transfusions carried out in 19 pregnant women. 52 procedures were performed directly into the umbilical vein, which is not innervated, so neutral for the fetus (the PCI group) and 29 transfusions into the intrahepatic vein -which puncture is stressful for the fetus (the IHV group). ACTH and cortisol concentrations in fetal and maternal plasma obtained during the procedures were assayed. The initial mean plasma ACTH concentration in the PCI group equaled 18.94pg/mL, but in the IHV group it was significantly higher and amounted 75.17pg/mL (p<0.001). There was no significant change in the hormone concentration during the transfusion both in the IHV group (95.8pg/mL, p>0.05) and in the PCI group (22.36pg/mL, p>0.05). The observed hormonal response in the IHV group proves the existence of fetal pituitary reaction to stress. The initial fetal ACTH concentration in the IHV group correlated with the number of transfusions performed on a single fetus (R=0.41; p=0.04). No correlation with parity, gestational weeks or the volume of transfused packed red blood cells was found. There was also no correlation between fetal and maternal ACTH concentrations in any group. Presented data suggest that the human fetus shows autonomous ACTH reaction to stress stimulation.  相似文献   
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Introduction

Atrial fibrillation (AF) is the most common arrhythmia and leads to a five-fold increased risk of stroke compared to persons with sinus rhythm. A soluble form of thrombomodulin (sTM) is a recognized marker of endothelial dysfunction and may contribute to the hypercoagulable state in AF. The aim of the study was to evaluate plasma concentration of sTM in persistent AF patients before and after sinus rhythm recovery following direct current cardioversion (CV).

Material and methods

In 45 effectively anticoagulated consecutive patients, with persistent non-valvular AF, and normal left ventricular function, CV was performed. Blood samples for sTM assessment were collected twice: 24 hours before and 24 hours after CV.

Results

In 43 patients sinus rhythm was obtained. The mean plasma sTM level was significantly lower in AF patients compared to the control group with sinus rhythm and without anticoagulation (38.5 ±9.9 ng/ml vs. 44.1 ±9.1 ng/ml, p = 0.04). Plasma sTM levels did not change 24 hours after successful CV (36.7 ±9.5 ng/ml vs. 38.5 ±9.9 ng/ml, p = 0.16).

Conclusions

Plasma sTM concentration was lower in patients with persistent AF and normal left ventricle systolic function than in patients with sinus rhythm, presumably due to chronic oral anticoagulant therapy in the AF group. CV has no impact on sTM plasma level evaluated 24 hours after sinus rhythm restoration.  相似文献   
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Background: Comparisons of physical fitness in normal weight and overweight/obese youth generally highlight the negative consequences of an elevated BMI. In contrast, several studies of children and adolescents highlight the importance of variation in indicators of physical fitness across the full spectrum of BMIs from low through high.

Aim: The purpose of the study was to evaluate relationships between specific physical fitness items and the BMI among youth.

Subjects and methods: Height, weight and six physical fitness tests were measured in 1239 males and 903 females, aged 13–16?years; BMI (kg/m2) was calculated. Fitness tests were compared by weight status using sex-specific MANCOVAs, controlling for age. Sex-specific quadratic regressions of each fitness item on the BMI were also calculated.

Results: The sprint, standing long jump and shuttle run indicated better performances in normal than in thin and overweight/obese boys; the latter groups did not differ. Thin and normal weight boys performed better than overweight/obese boys in sit-ups and distance run. Among girls, sit-ups differed as follows: normal?>?thin?>?overweight/obese. Thin and normal weight girls performed better than overweight/obese girls in the jump, distance run and shuttle run. Normal weight girls were faster in the sprint than the overweight/obese. The quadratic regressions indicated significant non-linear relationships between the BMI and all fitness items among boys and in four items among girls.

Conclusion: Performances on fitness tests varied with weight status. Relationships between performances and the BMI were curvilinear except for the distance run and flexibility in girls.  相似文献   
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