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排序方式: 共有280条查询结果,搜索用时 31 毫秒
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BACKGROUND: On December 26, 2004, the biggest earthquake for 40 years, measuring 9.0 on the Richter scale, triggered a tsunami that pounded the coastal areas of South Asia and East Africa. The effects of the tsunami on skin conditions have not been evaluated. OBJECTIVE: To determine the influence of the tsunami on skin conditions by evaluating the skin problems of patients presenting at hospitals after the tsunami. METHODS: Between 5 and 25 January 2005, two dermatologists evaluated patients who complained of skin problems at an outpatient clinic and emergency room of a general hospital in Banda Aceh, Aceh Province, Indonesia. RESULTS: The total number of patients that presented during the study period was 235 (131 males and 104 females), and they had a total of 265 skin problems. In terms of age distribution, most subjects were in their fourth decade (23.0%), followed by the third (22.6%) and fifth decade (16.6%). The most prevalent skin problems were infections-infestations (32.5%), followed by eczemas (29.8%) and traumatic skin disorders (29.4%). In males, traumatic skin disorders were most common. The great majority of infection-infestation cases involved superficial fungal infections. Contact dermatitis accounted for three-quarters of eczema cases, and mainly involved the arms (40.0%) and legs (27.1%). The majority of traumatic skin disorders were lacerations, punctures and penetrations, and the feet (44.7%) and hands (18.8%) were most frequently affected. CONCLUSIONS: Unhygienic conditions, exposure to a hazardous environment and contact with various objects during and after the tsunami probably increased the prevalence of infections-infestations, traumatic skin disorders and contact dermatitis. To prevent these problems and associated secondary bacterial infections, health-related education and early medical management are required.  相似文献   
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SUMMARY The study explored the incidence of clinical feminisation and the sex hormone levels of 18 Nigerian patients with liver cirrhosis (LC) alone and 18 patients with LC and hepatocellular carcinoma (HCC). The incidence (11%) of clinical feminisation in Nigerian patients was lower than values reported from other countries and there was no association between feminising signs and the sex hormone levels of the patients. Plasma oestradiol and sex hormone-binding globulin (SHBG) levels were significantly higher and testosterone lower in patients with liver diseases than in 18 age-matched normal controls. Serum concentrations of oestradiol were also found to be significantly higher in patients with LC alone than in those with LC and HCC. A possible promotive role for oestrogens in the development of HCC from the cirrhotic liver is discussed.  相似文献   
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Fiala  ES; Sohn  OS; Li  H; El-Bayoumy  K; Sodum  RS 《Carcinogenesis》1997,18(9):1809-1815
We observed that pretreatment of male F344 rats with benzyl selenocyanate, a versatile organoselenium chemopreventive agent in several animal model systems, decreases the levels of DNA and RNA modifications produced in the liver by the hepatocarcinogen 2- nitropropane. To clarify the mechanisms involved, we pretreated male F344 rats with either benzyl selenocyanate, its sulfur analog benzyl thiocyanate, phenobarbital or cobalt protoporphyrin IX; the latter is a depletor of P450. We then determined (1) the ability of liver microsomes to denitrify 2-nitropropane, (2) effects on 2-nitropropane- induced liver DNA and RNA modifications and (3) amount of nitrate excreted in rat urine following administration of the carcinogen. Pretreatment with benzyl selenocyanate or phenobarbital increased the denitrification activity of liver microsomes by 217 and 765%, respectively, increased liver P4502B1 by 31- and 435-fold, respectively, decreased the levels of 2-nitropropane-induced modifications in liver DNA (29-70% and 17-30%, respectively) and RNA (67-85% and 30-50%, respectively), and increased the 24-h urinary excretion of nitrate by 157 and 209%, respectively. Pretreatment with benzyl thiocyanate had no significant effect on any of these parameters. Pretreatment with cobalt protoporphyrin IX decreased liver P4502B 1 by 87%, decreased the denitrification activity of liver microsomes by 76%, decreased the 24 h urinary excretion of nitrate by 88.5%, but increased the extent of 2-nitropropane-induced liver nucleic acid modifications by 17-67%. These results indicate that the metabolic sequence from 2-nitropropane to the reactive species causing DNA and RNA modifications does not involve the removal of the nitro group. Moreover, they suggest that benzyl selenocyanate inhibits 2-NP-induced liver nucleic acid modifications in part by increasing its detoxication through induction of denitrification, although it is evident that other mechanisms must also be involved.   相似文献   
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BACKGROUND: Daytime sleepiness is common in patients with sleep-disordered breathing. Although respiratory events during sleep are associated with the occurrence of daytime sleepiness, the differential impact of these events during non-rapid eye movement (NREM) and rapid eye movement (REM) sleep on daytime sleepiness has not been well characterized. STUDY OBJECTIVES: To determine the effect of respiratory events during REM sleep and NREM sleep on daytime sleepiness, as assessed by the multiple sleep latency test (MSLT). DESIGN: Cross-sectional study. SETTING: University-based sleep disorders laboratory. PARTICIPANTS: Patients referred for polysomnography and daytime MSLT (n=1,821). INTERVENTIONS: N/A MEASUREMENTS AND RESULTS: The study sample was initially divided into quartiles based on the level of the apnea-hypopnea index (AHI) during NREM sleep. Within the first NREM-AHI quartile (NREM-AHI < 8.3 events/hr), the association between REM-related respiratory events and daytime sleepiness was examined using the method of Kaplan-Meier analysis and Cox proportional hazards regression. After adjusting for age, gender, body mass index, and the duration of NREM and REM sleep, REM-AHI was not associated with daytime sleepiness (Relative Risk: 1.01; 95%CI: 0.94-1.10). Similarly, no significant association was observed between REM-AHI and the MSLT in patients within the second through fourth NREM-AHI quartiles. In contrast, increasing severity of disordered breathing during NREM sleep was associated with daytime sleepiness. For a 10-point increase in NREM-AHI, the adjusted relative risks for daytime sleepiness in the second through fourth NREM-AHI quartile were 1.21 (95%CI: 1.01-1.46), 1.20 (95%CI: 1.05-1.37), and 1.10 (95%CI: 1.04-1.16), respectively. CONCLUSION: Sleep-disordered breathing during NREM sleep, but not REM sleep, is associated with increased risk of daytime sleepiness.  相似文献   
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Detection of Salmonella typhi in blood by culture of the mononuclear cell-platelet layer was compared with other methods currently used for the diagnosis of typhoid fever. Colonies of S. typhi were present in all mononuclear cell-platelet layer-positive cultures within 18 h of plating and were identified within an additional 10 min by a coagglutination technique. In contrast, identification of all positive cultures by conventional blood culture required 3 days.  相似文献   
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A randomized double-blind trial was conducted to evaluate the safety and immunogenicity of vaccines comprised of diphtheria (D) and tetanus (T) toxoids combined with either a whole cell (P) or an acellular (aP) pertussis component and Haemophilus influenzae type b polyribosylphosphate (PRP) tetanus toxoid conjugate (PRP-T) in Indonesian infants. Three doses of either DTaP, DTaP-PRP-T, or DTP-PRP-T were administered to 930 infants approximately 2-3 months of age and at 2 month intervals thereafter. A booster dose of either DTP-PRP-T or DTaP-PRP-T was administered at 15-18 months of age. Both local and systemic reactions occurred at a significantly (p < 0.001-0.026) higher rate in the group that received whole cell pertussis vaccine versus groups which were immunized with aP containing vaccines. There was no significant difference (p > 0.05) in the rate of adverse events between groups immunized with DTaP or DTaP PRP T. One month after the third dose of vaccine, 99% of subjects had achieved > or =0.1 IU of anti-D and anti-T antibody per ml of serum. The geometric mean titer (GMT) to D was significantly (p < 0.001) higher in the group immunized with DTaP versus the other two groups whereas the anti-T GMT was significantly (p < 0.006) higher for the group immunized with DTP-PRP-T. Both the anti-pertussis toxin (PT) and anti-filamentous hemagglutinin (FHA) antibody levels were significantly (p < 0.001) higher in recipients of acellular versus whole cell pertussis vaccine. In contrast, the anti-B. pertussis agglutinating antibody response was significantly (p < 0.0001) higher in the group immunized with whole cell pertussis vaccine. The anti-PRP GMTs (microg antibody/ml) at 7 months were 0.096, 3.35 and 6.11 for groups immunized with DTaP, DTaP-PRP-T and DTP-PRP-T, respectively. The GMT for those immunized with DTP-PRP-T was significantly (p < 0.001) higher compared to recipients of DTaP-PRP-T. The percent of children who attained > or =0.15 or > or =1 microg/ml after immunization was 18 and 2% for the DTaP group, 93 and 76% for the DTaP-PRP-T group and 97 and 88% for the DTP-PRP-T group. At the > or =1 microg/ml level the difference between the DTaP-PRP0-T and DTP-PRP-T groups was significant (p < 0.01). Children immunized with either DTaP, DTaP-PRP-T, or DTP-PRP-T were reimmunized with DTaP-PRP-T whereas a portion of children immunized with DTP PRP T where also boosted with this vaccine at 15-18 months of age. There was a vigorous anamnestic response to the D and T components with all children possessing > or =0.1 IU/ml. There was also a substantial increase in anti-PT, anti-FHA and B. pertussis agglutinating antibodies. The poorest anti-PT response was seen among children receiving DTP-PRP-T for both primary and reimmunization while the highest agglutinating antibody response followed receipt of 4 doses of DTP-PRP-T. Greater than 80% of children immunized with either DTP PRP T or DTaP-PRP-T possessed > or =0.15 microg/ml before boosting versus 38% for those vaccinated with DTaP (p < 0.001). Primary immunization with DTP-PRP-T resulted in a significantly (p < 0.05) higher percentage (72%) maintaining > or =1 microg/ml compared to those immunized with DTaP-PRP-T (46%). Prior to reimmunization, the anti-PRP GMT was significantly (p < 0.005) higher for children immunized with 3 doses of DTP-PRP-T versus DTaP-PRP-T. Subsequent to reimmunization, > or =95% of subjects attained > or =1 microg/ml.  相似文献   
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