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21.

Background  

Hypertension has been shown to start in early life and to track into adulthood. Detecting adolescents with hypertension and prehypertension will aid early intervention and reduce morbidity and mortality from the disorders. This study reports the point-prevalence of the two disorders in a semi-urban and an urban population of school-going adolescents in Nigeria.  相似文献   
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Severe traumatic injury is a public health care problem; with injuries accounting for 12% of the global mortality. Continued improvement in the survival of severely injured trauma patients is a paramount goal. Bailout/damage control surgery following trauma has developed as a major advance in surgical practice in the last twenty years. The principles of damage control surgery defied the traditional surgical teaching of definitive operative intervention and were slow to be adopted. Currently, damage control surgery has been successfully utilized to manage traumatic thoracic, abdominal, extremity, and peripheral vascular injuries. In addition, damage control surgery has been extrapolated for use in general, vascular, cardiac, urologic, and orthopaedic surgery. Stone et al were the first to describe the “bailout” approach of staged surgical procedures for severely injured patients. This approach emerged after their observation that early death following trauma was associated with severe metabolic and physiologic derangements following severe exsanguinating injuries. Profound shock along with major blood loss initiates the cycle of hypothermia, acidosis, and coagulopathy. During the 1980s, hypothermia, acidosis, and coagulopathy were described as the “trauma triangle of death” which makes the prolonged and definitive operative management of trauma patients dangerous. The management technique, now described as “damage control” by Rotondo et al, involves a multiphase approach, in which reoperation occurs after correction of physiologic abnormalities.  相似文献   
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The objective of this study was to evaluate the effect of subacute exposure to inhaled benzo(a)pyrene (BaP) on fetal survival and luteal maintenance using timed-pregnant Fisher 344 rats. Prior to assignment of pregnant rats to treatment and control groups, numbers of implantation sites were determined on gestation day (GD) 8 via midventral laparotomy. Subsequently, animals were assigned randomly to three treatment groups and two control groups. Treatment consisted of subacute exposure of rats via inhalation to BaP 25, 75, and 100 μg/m3, 4 h daily for 10 days (GD-11–20). Control animals were either sham exposed to carbon black (CB) to control for inert BaP carrier or remained unexposed (UNC). Blood samples were collected on days 15 and 17 of gestation via sinus orbital veini-puncture for plasma. Number of pups per litter was determined postpartum and fetal survival rate was expressed as a percentage of the corresponding implantation sites. Radioimmunoassays were used to determine plasma progesterone, estrogen, and prolactin (indirect measurement of decidual luteotropin) concentrations. Fetal survival among BaP-treated rats declined in a dose-dependent manner (25 μg/m3, 78.3% per litter; 75 μg/m3, 38.0% per litter; 100 μg/m3, 33.8% per litter; P<0.05) compared with CB (96.7% per litter) and UNC (98.9% per litter). Plasma progesterone, estrogen, and prolactin concentrations also declined as a result of subacute exposure of rats to BaP compared to controls. These data suggest that inhaled BaP compromised fetal survival and consequently luteotropic activity in the exposed animals.  相似文献   
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Previous reports indicate that metronidazole is highly effective in the therapy of colonic amebiasis and in the treatment of hepatic amebic abscesses when combined with aspiration. A retrospective review of 15 cases of intestinal amebiasis and 12 patients with amebic liver abscesses treated with metronidazole alone is reported. Based on the literature and the clinical response of the patients reported herein, metronidazole is the initial drug of choice in the therapy of amebic colitis because of its ease of administration, efficacy, and low toxicity. In the treatment of hepatic amebic abscesses, metronidazole alone is adequate therapy for most cases, but occasionally there will be progression of the disease despite standard dosages of the drug.  相似文献   
27.
The presence of HIV-2 in Nigeria has been confirmed serologically, but not genetically. To determine the frequency of HIV-2 infections and the dynamics between HIV-1 and HIV-2 in 35 of 36 Nigerian states, 420 blood samples were collected in 1999. Antibodies to HIV-1 and HIV-2 were detected by EIA and seroreactivity was confirmed with the INNO-LIA HIV Line Assay. The frequency of HIV-2 was 4.3% (18 of 420), with 3.8% (16 of 420) HIV-1 and HIV-2 (HIV-1/2) heterotypic and 0.5% (2 of 420) HIV-2 homotypic infections. The presence of HIV-2 subtype B in the two monotypic HIV-2 infections and subtype A in 11 (68.8%) of 16 HIV-1/2 dually seropositive samples was established by sequencing and phylogenetic analysis. HIV-2 subtype B viruses were not found in any of the HIV-1/2 dual infections, and HIV-2 subtype A strains were not identified in either of the two monotypic HIV-2 infections. Since our sample size was small and represented only convenience samples, larger randomized studies will be needed to better understand the dynamics of infection between HIV-1 and different HIV-2 subtypes and to determine whether significant biological differences exist among the HIV- 2 subtypes.  相似文献   
28.
This study seeks to elucidate the role of diethylstilbestrol (DES), a synthetic estrogen on benzo(a)pyrene (BaP) metabolism in the male rat reproductive tissues. Offspring of timed-pregnant Sprague-Dawley rats were neonatally treated on days 2, 4, and 6 post-partum with 1.45 micromol/kg of DES. Ten weeks after birth, the adult rats were challenged with radiolabeled benzo(a)pyrene (3H BaP) (10 micromol/kg) and the rats were sacrificed 2 h after BaP exposure. Prostrate, testis, lung, liver, urine and feces samples were collected and extracted using a mixture of H2O, MeOH and CHCl3. The extracts were analyzed by reverse phase HPLC. The concentrations of BaP organic metabolites in DES rats were lower compared to controls (vehicle-treated rats). On the other hand, concentrations of aqueous metabolites were significantly increased in DES treated animals. The toxication to detoxication ratios were significantly decreased in DES rats compared to controls. This trend is also reflected in the decreased concentrations of BaP-DNA adducts in DES rats. Collectively these results suggest that DES is capable of modulating the metabolic pathway of BaP towards detoxification thereby preventing the manifestation of toxicity.  相似文献   
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