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71.
International Urology and Nephrology - Studies based on administrative databases show that infant pyeloplasty is associated with minority race/ethnicity but lack clinical data that may influence...  相似文献   
72.
Needle biopsy of renal allografts: comparison of two techniques   总被引:2,自引:0,他引:2  
Two techniques for renal allograft biopsy were retrospectively evaluated to compare relative safety and efficacy. After ultrasound (US) localization of the kidney and biopsy with a hand-held 14-gauge cutting needle, an adequate specimen was obtained in 74 of 77 cases (96%). Major complications occurred in six of these 77 cases (8%). One hundred four biopsies were performed by using a smaller 18-gauge cutting needle with a spring-loaded biopsy "gun" and real-time US guidance. With this newer technique, specimens adequate for diagnosis were obtained in 99 biopsies (95%). There was a single major complication with this technique (1%). The 18-gauge needle with real-time US guidance yields comparably adequate specimens with a lower frequency of complications.  相似文献   
73.
As long as drug use and abuse persist in our society, a significant number of patients with various types of drug withdrawal will present to Emergency Departments. It is imperative that we recognize the signs and symptoms of drug withdrawal and render the appropriate treatments. Although it may be easy to recognize "skid row" alcoholics, a drug abuser with track marks on his (or her) arms or with a perforated nasal septum, the executive alcoholic, the elderly patient on chronic diazepam therapy, or the "blue collar" worker using cocaine may be more common and more elusive. Because most drug abusers use and can be dependent on multiple drugs, detoxification may need to proceed with one drug or one class of drugs at a time. Although our discussion has concentrated on the acute presentation and treatment of these symptoms for the emergency physician, we recognize that the acute treatment of withdrawal symptoms is only a small but vital part of withdrawal treatment. These patients will require chronic treatment, including social and psychologic counseling. As emergency physicians, by performing our jobs of recognition, stabilization, and counseling, we will fulfill the first critical link in the treatment of these patients.  相似文献   
74.
Both experimental and epidemiologic studies have linked a low dietary intake of selenium with an increased risk of cancer. The authors examined the association between plasma selenium levels and risk of hepatocellular carcinoma (HCC) among chronic carriers of hepatitis B and/or C virus in a cohort of 7,342 men in Taiwan who were recruited by personal interview and blood draw during 1988-1992. After these men were followed up for an average of 5.3 years, selenium levels in the stored plasma were measured by using hydride atomic absorption spectrometry for 69 incident HCC cases who were positive for hepatitis B surface antigen (HBsAg) and/or antibodies against hepatitis C virus (mostly HBsAg positive) and 139 matched, healthy controls who were HBsAg positive. Mean selenium levels were significantly lower in the HCC cases than in the HBsAg-positive controls (p = 0.01). Adjusted odds ratios of HCC for subjects in increasing quintiles of plasma selenium were 1.00, 0.52, 0.32, 0.19, and 0.62, respectively. The inverse association between plasma selenium levels and HCC was most striking among cigarette smokers and among subjects with low plasma levels of retinol or various carotenoids. There was no clear evidence for an interaction between selenium and alpha-tocopherol in relation to HCC risk.  相似文献   
75.
Identification of carcinogens in cooking oil fumes.   总被引:8,自引:0,他引:8  
According to earlier studies, fumes from cooking oils were found to be genotoxic in several short-term tests such as the Ames test, sister chromatid exchange, and SOS chromotest. Fume samples from six different commercial cooking oils (safflower, olive, coconut, mustard, vegetable, and corn) frequently used in Taiwan were collected. Polycyclic aromatic hydrocarbons (PAHs) were extracted from the air samples and identified by high-performance liquid chromatography and confirmed by gas chromatography/mass spectrometry. Extracts of fumes from safflower oil, vegetable oil, and corn oil contained benzo[a]pyrene (BaP), dibenz[a,h]anthracene (DBahA), benzo[b]fluoranthene (BbFA), and benzo[a]anthracene (BaA). Concentrations of BaP, DbahA, BbFA, and BaA were 2.1, 2.8, 1.8, and 2.5 microg/m3 in fumes from safflower oil; 2.7, 3.2, 2.6, and 2.1 microg/m3 in vegetable oil; and 2.6, 2.4, 2.0, and 1.9 microg/m3 in corn oil, respectively. The authors constructed models to study the efficacy of table-edged fume extractors used commonly by Taiwanese restaurants. Concentrations of BaP were significantly decreased when the fume extractor was working (P<0.05) and the average reduction in percentage was 75%. The other identified PAHs were undetected. These results indicated that exposure to cooking oil fumes could possibly increase exposure to PAHs, which may be linked to an increased risk of lung cancer. The potential carcinogenic exposure could be reduced by placing table-edged fume extractors near cooking pots.  相似文献   
76.
The aim of the present study was to examine the in vivo effect of interleukin (IL)-12 on a murine model of asthma induced by Dermatophagoides pteronyssinus-derived Der p 1 allergen. C57BL/6 mice immunized with Der p 1 allergen adsorbed to alum/pertussis toxin developed a T-helper type 2 (Th2)-dominant immune response characterized by the presence of IgE antibody, airway eosinophil infiltration and increased production of Th2 cytokine. Intraperitoneal injection of IL-12 (1 or 0.1 microg per day) for 5 days (day -1 to +3) simultaneously with each immunization, inhibited the production of IgE and IgG1 antigen-specific antibodies, whereas production of IgG2a was strongly enhanced. In addition, mice receiving both doses of IL-12 showed a strong inhibition of IL-5 but up-regulation of IFN-gamma production by spleen cells stimulated with antigen. Administration of IL-12 also prevented antigen-induced eosinophil infiltration into the bronchoalveolar area in a dose-dependent manner and the primary inflammatory mediator serotonin in bronchoalveolar lavage (BAL) fluids was also reduced significantly. Taken together, the data indicate that IL-12 has a potent immunomodulatory effect on house-dust-mite-induced allergic disorders and may be used as an efficient agent for immunotherapy.  相似文献   
77.
PURPOSE: To investigate cytokine gene expression in the lung after single and fractionated doses of radiation, and to investigate the effect of steroids and the genetic background. MATERIALS AND METHODS: Expression of cytokine genes (mTNF-alpha, mIL-1alpha, mIL-1beta, mIL-2, mIL-3, mIL-4, mIL-5, mIL-6, mIFN-gamma) in the lungs of C3H/HeJ and C57BL/6J mice was measured by RNase protection assay at different times after various doses of radiation. The effects of dexamethasone and fractionated radiation treatment on gene expression were also studied. RESULTS: IL-1beta was the major cytokine induced in the lungs of C3H/HeJ mice within the first day after thoracic irradiation. Radiation doses as low as 1 Gy were effective. Responses to 20 Gy irradiation peaked within 4-8h and subsided by 24 h. With the exception of IL-1alpha and TNF-alpha, the other cytokines that were investigated had undetectable pre-treatment mRNA levels and were not radiation inducible. Similar responses were seen in C57BL/6J mice, although TNF-alpha was induced and there were some quantitative differences. Pre-treatment of C3H/HeJ mice with dexamethasone reduced basal and induced IL-1 levels, but complete inhibition was not achieved. Dexamethasone was also effective if given immediately after irradiation. Fractionated daily doses of radiation (4 Gy/day) helped to maintain cytokine gene expression for a longer period. CONCLUSIONS: Inflammatory genes are rapidly induced in the lung by irradiation. This response cannot be readily abolished by steroid pre-treatment. Fractionated treatment schedules help to perpetuate the response.  相似文献   
78.
79.
Antioxidants attenuate noncholinergic airway constriction. To further investigate the relationship between tachykinin-mediated airway constriction and oxygen radicals, we explored citric acid-induced bronchial constriction in 48 young Hartley strain guinea-pigs, divided into six groups: control; citric acid; hexa(sulphobutyl)fullerenes + citric acid; hexa(sulphobutyl)fullerenes + phosphoramidon + citric acid; dimethylthiourea (DMTU) + citric acid; and DMTU + phosphoramidon + citric acid. Hexa(sulphobutyl)fullerenes and DMTU are scavengers of oxygen radicals while phosphoramidon is an inhibitor of the major degradation enzyme for tachykinins. Animals were anaesthetized, paralyzed, and artificially ventilated. Each animal was given 50 breaths of 4 ml saline or citric acid aerosol. We measured dynamic respiratory compliance (Crs), forced expiratory volume in 0.1 (FEV0.1), and maximal expiratory flow at 30% total lung capacity (Vmax30) to evaluate the degree of airway constriction. Citric acid, but not saline, aerosol inhalation caused marked decreases in Crs, FEV0.1 and Vmax30, indicating marked airway constriction. This constriction was significantly attenuated by either hexa(sulphobutyl)fullerenes or by DMTU. In addition, phosphoramidon significantly reversed the attenuating action of hexa(sulphobutyl)fullerenes, but not that of DMTU. Citric acid aerosol inhalation caused increases in both lucigenin- and t-butyl hydroperoxide-initiated chemiluminescence counts, indicating citric acid-induced increase in oxygen radicals and decrease in antioxidants in bronchoalveolar lavage fluid. These alterations were significantly suppressed by either hexa(sulphobutyl)fullerenes or DMTU. An elastase inhibitor eglin-c also significantly attenuated citric acid-induced airway constriction, indicating the contributing role of elastase in this type of constriction. We conclude that both oxygen radicals and elastase play an important role in tachykinin-mediated, citric acid-induced airway constriction.  相似文献   
80.
Cytokines predict coronary aneurysm formation in Kawasaki disease patients   总被引:5,自引:0,他引:5  
In this study, we measured serially the serum levels of cytokines including interleukin-6 (IL-6), IL-8, soluble IL-2 receptor (sIL-2R) and tumour necrosis factor (TNF-) in 60 patients with Kawasaki disease (KD) and evaluated the clinical significance of these cytokines in predicting coronary aneurysm formation. Of the 60 patients, 12 were complicated with coronary aneurysm. Blood samples were collected within the 1st week after onset of fever, then once a week for the 1st month, and once a month for another 5 months. The serum levels of IL-6, IL-8, sIL-2R and TNF were measured using an ELISA or RIA method. Our results show that the changes in serum IL-6 and IL-8 were faster than those of sIL-2R and TNF. Within the 1st week, the serum levels of IL-6 and IL-8 were significantly higher in the patients with than in those without coronary aneurysm (P<0.001). In addition, the serum levels of IL-6 and IL-8 obtained in the 1st week were highly correlated (P<0.001) with those of C-reactive protein and erythrocyte sedimentation rate, and the serum levels of sIL-2R and TNF were also increased at the 1st week reaching the highest level in the 2nd week. In the 2nd week, the serum levels of sIL-2R and TNF were significantly higher in the patients with than in those without coronary aneurysm (P<0.05). These findings suggest that the serum levels of IL-6 and IL-8 obtained in the 1st week may serve as useful parameters in predicting coronary aneurysm formation in KD patients.  相似文献   
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