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51.
BACKGROUND: The objective of this study was to document the status of malaria infection and effect of preventive measures on the epidemiologic profile of imported malaria cases in Kuwait during 1985-2000. METHODS: The study included screening of two groups of individuals for malaria infection by microscopy; (1) all migrant workers from malaria-endemic countries on their first entry to Kuwait; and (2) all suspected malaria cases already residing in the country. The study period was divided into pre-war (1985-1990), postwar (1992-1997) and proactive preventive (1998-2000) periods. During the proactive preventive period, the home countries were also involved in screening for malaria infection in all prospective immigrants to Kuwait. RESULTS: The annual incidence of malaria cases detected during the pre-war, postwar and proactive preventive periods ranged between 465 and 1,229, 654 and 1,379, and 248 and 393, respectively. Plasmodium vivax infection was detected in 71% of the cases and P. falciparum in 27%. The number of malaria cases detected increased to >1,300 after the war during 1992-1993. However, the number of malaria cases dropped significantly to less than 400 during 1998-2000 (p80%) of malaria patients were young male adults between 21 and 40 years of age. The data on drug resistance were not well defined, due to limited testing. CONCLUSION: This study suggests that the proactive preventive program to screen all prospective immigrants for malaria infection in their home countries significantly reduced the numbers of imported infections to <400 cases/year, a drop of 52.6%. In addition, it also identified a group of settled immigrants, the majority of whom were at high risk for acquisition of malaria infection during their visit to home countries. There is an urgent need to target this group for prevention strategies such as education/information and other preventive measures against malaria infection.  相似文献   
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53.
In human infection withSchistosoma mansoni from Beni-Suef, the eggs were encountered more frequently in the urine of patients than in infection withS. mansoni from Giza, where eggs were passed into the stool. A comparative study of the two strains ofS. mansoni from Beni-Suef and Giza has been carried out in golden hamster. Consistent strain differences were observed. The Beni-Suef strain proved to have lower worm recovery and different egg distribution patterns in tissues of infected hamsters. Worms of both sexes of this strain were larger in size and required a longer period to reach maturity. Hence, the prepatent period was prolonged. Significant differences between the two strains were also noted in the number of eggs per worm. A lower mortality rate and a longer survival time were encountered in hamsters infected with the Beni-Suef strain.This work was supported by the Naval Medical Research and Development Command, NMC, NCR, Bethesda, MD. Work Unit No. 3M161102BS10.AA421  相似文献   
54.
The aim of this work was to identify ventricular shape-based biomarkers in MR images to discriminate between patients with Alzheimer's disease (AD) and healthy elderly. Clinical MR images were collected for 58 patients and 28 age-matched healthy controls. After normalizing all the images the ventricular cerebrospinal fluid was semiautomatically extracted for each subject and an innovative technique for fully automatic shape modeling was applied to generate comparable meshes of all ventricles. The search for potential biomarkers was carried out with repeated permutation tests: results highlighted well-defined areas of the ventricular surface being discriminating features for AD: the left inferior medial temporal horn, the right medial temporal horn (superior and inferior), and the areas close to the left anterior part of the corpus callosum and the head of the right caudate nucleus. The biomarkers were then used as features to build an intelligent machine for AD detection: a Support Vector Machine was trained on AD and healthy subjects and subsequently tested with leave-1-out experiments and validation tests on previously unseen cases. The results showed a sensitivity of 76% for AD, with an overall accuracy of 84%, proving that suitable biomarkers for AD can be detected in clinical MR images.  相似文献   
55.
Rhythm-generating neural circuits underlying diverse behaviors such as locomotion, sleep states, digestion and respiration play critical roles in our lives. Irregularities in these rhythmic behaviors characterize disease states – thus, it is essential that we identify the ionic and/or cellular mechanisms that are necessary for triggering these rhythmic behaviors on a regular basis. Here, we examine which ionic conductances underlie regular or ‘stable’ respiratory activities, which are proposed to underlie eupnea, or normal quiet breathing. We used a mouse in vitro medullary slice preparation containing the rhythmogenic respiratory neural circuit, called the preBötzinger complex (preBötC), that underlies inspiratory respiratory activity. We varied either [K+]o or [Na+]o, or blocked voltage-gated calcium channels, while recording from synaptically isolated respiratory pacemakers, and examined which of these manipulations resulted in their endogenous bursting becoming more irregular. Of these, lowering [Na+]o increased the irregularity of endogenous bursting by synaptically isolated pacemakers. Lowering [Na+]o also decreased the regularity of fictive eupneic activity generated by the ventral respiratory group (VRG) population and hypoglossal motor output. Voltage clamp data indicate that lowering [Na+]o, in a range that results in irregular population rhythm generation, decreased persistent sodium currents, but not transient sodium currents underlying action potentials. Our data suggest that background sodium currents play a major role in determining the regularity of the fictive eupneic respiratory rhythm.  相似文献   
56.
Acute tumor lysis syndrome (ATLS) is a well-described oncological emergency that is usually associated with hematological malignan-cies complicated by treatment. It is typically related to a high tumor burden, rapidly growing and chemosensitive malignancies.  相似文献   
57.
HYPOTHESIS: Mortality in children with shock is more closely related to the nature, rather than the magnitude (base deficit/excess), of a metabolic acidosis. OBJECTIVE: To examine the relationship between base excess (BE), hyperlactataemia, hyperchloraemia, 'unmeasured' strong anions, and mortality. DESIGN: Prospective observational study set in a multi-disciplinary Paediatric Intensive Care Unit (PICU). PATIENTS: Forty-six children, median age 6 months (1.5-14.4), median weight 5 kg (3.2-8.8), admitted to PICU with shock. INTERVENTIONS: Predicted mortality was calculated from the paediatric index of mortality (PIM) score. The pH, base excess, serum lactate, corrected chloride, and 'unmeasured' strong anions (Strong Ion Gap) were measured or calculated at admission and 24 h. MEASUREMENTS AND RESULTS: Observed mortality ( n=16) was 35%, with a standardised mortality ratio (SMR) of 1.03 (95% CI 0.71-1.35). There was no significant difference in admission pH or BE between survivors and nonsurvivors. There was no association between elevation of 'unmeasured' anions and mortality, although there was a trend towards hyperchloraemia in survivors ( P=0.08). Admission lactate was higher in nonsurvivors (median 11.6 vs 3.3 mmol/l; P=0.0003). Area under the mortality receiver operating characteristic curve for lactate was 0.83 (955 CI 0.70-0.95), compared to 0.71 (95% CI 0.53-0.88) for the PIM score. Admission lactate level >5 mmol/l had maximum diagnostic efficiency for mortality, with a likelihood ratio of 2.0. CONCLUSION: There is no association between the magnitude of metabolic acidosis, quantified by the base excess, and mortality in children with shock. Hyperlactataemia, but not elevation of 'unmeasured' anions, is predictive of a poor outcome.  相似文献   
58.
Rib fracture secondary to blunt chest trauma is an indicator of the severity of injury. It is one of the factors associated with morbidity and mortality in blunt chest trauma. Current management of such patients stresses on provision of adequate analgesia and early institution of aggressive physiotherapy. The current study evaluates the analgesic efficacy of continuous thoracic paravertebral infusion of Bupivacaine in unilateral multiple rib fracture (MRF).

Study design

Retrospective, non-randomized case series of 11 patients with unilateral MRF.

Method

Thoracic paravertebral (TPV) space on the side of fractured ribs was catheterized with an epidural catheter. TPV block was initiated with 0.3 ml/kg body weight of 0.25% Bupivacaine with adrenaline. The block was maintained with a continuous infusion of 0.2% Bupivacaine 30 min later, at 0.1–0.2 ml/(kg/h) for a total of 4 days or for the length of admission, which ever was earlier.

Patients were monitored for pain scores at rest and when asked to cough and vital capacity manoeuvre, respiratory rate, oxygen saturation, oxygen index (PaO2/FiO2) and percentage change in incentive spirometry.

There were significant improvements in pain scores at rest (p = 0.0097), on cough (p = 0.0039) and vital capacity manoeuvre (p = 0.0078). Other respiratory parameters like respiratory rate, PaO2 and oxygen index showed persistent improvement from baseline. None of the patients had any complications or side effect related to procedure and technique.

Conclusion

Our study confirms that continuous TPV block is a safe and effective technique for analgesia in patients with unilateral MRF.  相似文献   

59.
BACKGROUND/AIMS: Alcohol use and hepatitis C are prominent risk factors for liver injury and this review offers the current understanding of each factor's effects on liver disease. METHODS: A Medline database search was preformed for English articles with a focus on alcohol, hepatitis C and liver disease. Article citations were also considered for further applicable articles, and the strongest studies were included in our review. RESULTS: Up to 60% of patients with hepatitis C have a past history of alcohol use. In patients with hepatitis C, chronic alcohol consumption of more than 5 drinks/day increases the rate of liver fibrosis, risk for cirrhosis, hepatocellular carcinoma, and, possibly, death from liver disease. Numerous studies have further found that even moderate amounts of alcohol can be detrimental to hepatitis C patients. The prevalence of hepatitis C is higher in alcoholics with advanced liver disease than in alcoholics without liver disease. Also, recent alcohol use decreases the response rate to interferon treatment. CONCLUSIONS: Hepatitis C and alcohol use are often co-occurring risk factors for liver disease, and though their interaction is not clear, it is known that heavy drinking significantly promotes liver disease progression.  相似文献   
60.
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