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排序方式: 共有875条查询结果,搜索用时 203 毫秒
31.
Tauber E Fazekas T Eichler I Eichstill C Gartner C Koller DY Frischer T 《Pediatric pulmonology》2003,35(3):162-168
The negative expiratory pressure technique (NEP) has been applied in adults with chronic obstructive pulmonary disease (COPD), demonstrating flow limitation in many of these patients. Because this technique does not require patient cooperation, it is of potential interest for application in the pediatric population. This study was performed to test the feasibility of NEP in children, and to further investigate it in children with asthma and cystic fibrosis (CF). We performed NEP (0.3-0.7 kPa) measurements in 14 healthy children (13.3 years, +/- 2.4), in 12 children with asthma (11.7 years, +/- 3.0), and in 17 children with CF (13.3 years, +/- 2.7). NEP-derived flow-volume loops were visually analyzed for flow limitation at tidal breathing. In addition, expiratory flow at 50% of tidal volume (TEF(50)) was measured. In healthy children, the intraclass coefficient of correlation was 77%, and intraindividual short- and long-term variability was 5.8% and 10.8%, respectively. In asthmatics, TEF(50) was lower compared with controls, and increased after inhalation of salbutamol. However, appropriate size-correction has still to be established. Measurement of TEF(50) using NEP is feasible in children. Despite good reproducibility in individual patients, the high intersubject variability may limit its usefulness as a clinical tool. In addition, the lack of flow limitation using NEP even in severely obstructed patients with CF warrants further investigation. 相似文献
32.
Röckl-Wiedmann I Meyer N Fischer R Laubereau B Weitkunat R Uberla K 《Sozial- und Pr?ventivmedizin》2002,47(5):307-317
OBJECTIVES: This article aims to analyse utilisation of medical services and screening programmes in relation to social class. METHODS: 2051 adults in Bavaria were interviewed using computer-assisted telephone interview (CATI) in 1999/2000. Social class was established from the income-adjusted Winkler social category index. Data were standardised by age and sex. If social class differences were found, separate analyses for education and income effects were conducted. RESULTS: Higher education was found to be associated with visits to specialist and vaccinations. The purchase of over-the-counter medication was related to higher education and family income. Frequency of HIV-tests was higher in higher social classes but not related to higher education or better financial situation. Utilisation rates for screening programmes for various types of cancer were similar in all social classes. CONCLUSIONS: The results show that social class differences in health behaviour in Bavaria prevail. Positive health behaviour is often associated with higher education. Compared to earlier findings social class effects on the utilisation of cancer screening appears less pronounced. Preventive measures seem to have reached all social classes to a similar degree. 相似文献
33.
Smad4 induces the tumor suppressor E-cadherin and P-cadherin in colon carcinoma cells 总被引:14,自引:0,他引:14
Müller N Reinacher-Schick A Baldus S van Hengel J Berx G Baar A van Roy F Schmiegel W Schwarte-Waldhoff I 《Oncogene》2002,21(39):6049-6058
34.
Jiyoung Ahn Christine B Ambrosone Peter A Kanetsky Chunqiao Tian Teresa A Lehman Silke Kropp Irmgard Helmbold Dietrich von Fournier Wulf Haase Marie Luise Sautter-Bihl Frederik Wenz Jenny Chang-Claude 《Clinical cancer research》2006,12(23):7063-7070
PURPOSE: Because radiotherapy exerts cytotoxic effects via generation of massive oxidative stress, we hypothesized that catalase, manganese superoxide dismutase, myeloperoxidase (MPO), and endothelial nitric oxide synthase (eNOS) genotypes might result in greater risk of radiotoxicity. EXPERIMENTAL DESIGN: Cases (n = 446) were Caucasian women with breast cancer who received radiotherapy following lumpectomy. Genotypes were determined by matrix-assisted laser desorption/ionization time-of-flight. The development of acute reactions (moist desquamation) associated with genotypes was modeled using the Cox proportional hazards model, accounting for cumulative biologically effective radiation dose. RESULTS: Genotypes associated with higher levels of reactive oxygen species (ROS) were not associated with risk of radiotoxicity. However, relationships between overweight/obesity [body mass index (BMI), >25] and radiotoxicity risk seemed to be modified by eNOS and MPO genotypes associated with higher generation of nitric oxide and ROS, respectively. Women with high BMI (>25) and eNOS GG genotypes were at more than a 6-fold increase in risk (hazard ratio, 6.39; 95% confidence interval, 2.53-16.15) compared with those with BMI <25, and for MPO, those with high BMI (>25) and GG genotypes also had greater risk of radiotoxicity (hazard ratio, 3.61; 95% confidence interval, 1.78-7.35) compared with those with BMI <25. Overweight/obesity was not a strong risk factor among women with other eNOS and MPO genotypes. Exploratory analysis using classification and regression trees indicated that total number of risk alleles contributed, in part, to acute toxicity outcomes among a subgroup of women. CONCLUSIONS: Associations between BMI and radiotoxicity risk may be most apparent among women with genotypes related to higher levels of oxidative stress. Regression trees may be useful in future studies to examine the contributions of multiple factors to individual susceptibility to adverse effects of cancer treatment. 相似文献
35.
36.
Margit Bauer Irmgard Orescovic Wolfgang M Schoell Diana W Bianchi Barbara Pertl 《American journal of obstetrics and gynecology》2002,186(1):117-120
OBJECTIVE: Umbilical cord blood is a source of hematopoietic stem cells for transplantation. Although the first clinical applications have been encouraging, concern has been raised about contamination of umbilical blood by maternal cells, which might constitute a theoretical risk of graft-versus-host disease. The aim of this study was to assess the frequency of maternal deoxyribonucleic acid (DNA) contamination in umbilical cord plasma by using fluorescent polymerase chain reaction amplification of highly polymorphic short tandem repeat DNA markers. STUDY DESIGN: Fifty-seven mother/child pairs were tested for the presence of maternal DNA sequences in cord plasma. After delivery, cord blood samples were collected via gravity. Maternal specific alleles were detected by using polymerase chain reaction amplification of 9 highly polymorphic short tandem repeat markers (D21S11, D21S1411, D21S1412, D18S386, D18S535, MBP-A, MBP-B, D13S631, and D13S634). RESULTS: All 57 mother-child pairs were informative for the identification of uniquely maternal alleles in at least 2 of 9 different short tandem repeat markers used per case. Uniquely maternal DNA sequences were found in 43 of 57 (75%) cord plasma samples. CONCLUSION: The results of our study demonstrate that maternal DNA is present in the majority of umbilical cord blood plasma samples. The technique described herein might have application in the screening of umbilical cord blood samples for the presence of contaminating maternal genetic material. 相似文献
37.
38.
Pelvic ultrasonographic (US) studies of four patients (ages 11–19 years) with Turner's syndrome, 45,X karyotype, and normal ovarian function were reviewed. All four had persistent menses, spontaneous breast development, and normal follicular stimulant hormone (FSH) serum concentrations. The US studies depicted normal postpubertal uterus and normal-sized ovaries with follicles. In three patients, ovaries were seen bilaterally, while in one only one gonad was identified. Radiologists should be aware that patients with Turner's syndrome, even with a single X chromosome, may occasionally have normal genital development. 相似文献
39.
40.
Parathyroid adenomas evaluated by Tl-201/Tc-99m pertechnetate subtraction scintigraphy and high-resolution ultrasonography 总被引:2,自引:0,他引:2
Winzelberg GG; Hydovitz JD; O'Hara KR; Anderson KM; Turbiner E; Danowski TS; Lippe RD; Melada GA; Harrison AM 《Radiology》1985,155(1):231-235
Thallium-201/technetium-99m pertechnetate subtraction scintigraphy of the parathyroid glands was performed in a prospective study of 33 patients who had undergone bilateral neck exploration for elevated serum calcium and serum parathyroid hormone levels. In 31 cases, the Tl-201/Tc-99m subtraction technique yielded an overall sensitivity of 81%, specificity of 99%, and accuracy of 94% for identifying solitary parathyroid adenomas. Tl-201/Tc-99m subtraction scintigraphy correctly identified 73% of parathyroid adenomas weighing less than 499 mg, 79% of those weighing 500-1,499 mg, and 100% of adenomas weighing more than 1,500 mg. In a subgroup of 24 patients with solitary parathyroid adenomas who underwent both scintigraphy and high-resolution sonography, the sensitivity, specificity, and accuracy of both procedures were similar. 相似文献