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OBJECTIVE: To investigate the hemodynamic effects of a moderately low-salt diet in a 9-week, randomized, double-blind, crossover study in 20 hypertensive, ambulatory patients. METHODS: All subjects followed a 9-week, low-salt diet. During this period, they received capsules containing either lactose or salt in 4-week treatment periods, separated by a 1-week washout period. Hemodynamic and biological parameters were evaluated on the day of randomization and at the end of weeks 4 and 9. We defined a low-sodium diet (LSD) as a salt-restriction period with lactose capsules, and a normal-sodium diet (NSD) as a salt-restriction period with capsular salt supplementation. RESULTS: Blood pressure was significantly lower during LSD compared with NSD. This fall in blood pressure was associated with a decrease in peripheral resistance in carotid and forearm circulation. Brachial artery diameter was larger during LSD whereas carotid artery diameter remained unchanged. The changes in brachial artery were: (1) not related to blood pressure changes; (2) positively related to age, and (3) negatively correlated with baseline intracellular sodium content. CONCLUSIONS: These results suggest that moderate low-salt restriction is capable of decreasing blood pressure and peripheral resistance in carotid and forearm circulation. The increase in brachial, but not carotid, artery diameter following salt restriction suggests a difference in salt dependence among different arteries.  相似文献   
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Admissions for scorpion sting in 1 year and deaths resulting from scorpion sting over 3 years were analysed. Features that indicated the severity of the clinical condition were identified. Pulmonary oedema and shock were the usual causes of death. Poor management of fluid therapy was responsible for the frequently unsatisfactory resolution of envenoming, especially when purified human plasma was used. The role of the scorpion antivenom used is questioned and controversy regarding the most appropriate sedative to use in the management of scorpion sting is still not resolved. An in-depth study of these management issues is urgently required.  相似文献   
4.
Levels of brain creatine kinase (CK), aspartate aminotransferase (ASAT), and lactate dehydrogenase (LD) in CSF after cardiac arrest were studied in dog models. Ventricular fibrillation cardiac arrest lasting 10 min or asphyxiation cardiac arrest lasting 0-10 min was followed by cardiopulmonary resuscitation and 96-h intensive care. Outcome was scored as neurologic deficit (0% = normal, 100% = brain death) and overall performance category (1 = normal, 5 = death). Both measures correlated with EEG return time after asphyxiation cardiac arrest, but not after ventricular fibrillation cardiac arrest. Peak activity of enzymes in CSF at 48-72 h post arrest correlated with outcome, and CK was the best predictor. Brain histopathologic damage score at autopsy 96 h post arrest correlated with CK level in CSF (r = 0.79, n = 39) and neurologic deficit (r = 0.70, n = 50). Ischemic neuronal changes occurred after ventricular fibrillation cardiac arrest of 10 min, and neuronal changes plus microinfarcts occurred after asphyxiation cardiac arrest of 1.5-10 min. Brain enzymes were decreased at 6 h post arrest in regions with worst histologic damage (gray matter of neocortex, hippocampus, caudate nucleus, cerebellum). Brain CK decreased further, ASAT remained low, and LD increased at 72 h after arrest. The temporal changes in CK level paralleled the temporal ischemic neuronal changes in the brain, and time to peak activity was unaffected by the severity of the ischemic insult. Peak activity of individual enzymes in CSF was determined predominantly by the brain concentration, but was also influenced by rate of decomposition. This "chemical brain biopsy method" represents a useful adjunctive tool to predict permanent, severe brain damage during comatose states after cardiac arrest and resuscitation.  相似文献   
5.
Helicobacter pylori is a common and persistent human pathogen of the gastric mucosa. Surfactant protein D (SP-D), a component of innate immunity, is expressed in the human gastric mucosa and is capable of aggregating H. pylori. Wide variation in the SP-D binding affinity to H. pylori has been observed in clinical isolates and laboratory-adapted strains. The aim of this study was to reveal potential mechanisms responsible for evading SP-D binding and establishing persistent infection. An escape variant, J178V, was generated in vitro, and the lipopolysaccharide (LPS) structure of the variant was compared to that of the parental strain, J178. The genetic basis for structural variation was explored by sequencing LPS biosynthesis genes. SP-D binding to clinical isolates was demonstrated by fluorescence-activated cell sorter analyses. Here, we show that H. pylori evades SP-D binding through phase variation in lipopolysaccharide. This phenomenon is linked to changes in the fucosylation of the O chain, which was concomitant with slipped-strand mispairing in a poly(C) tract of the fucosyltransferase A (fucT1) gene. SP-D binding organisms are predominant in mucus in vivo (P = 0.02), suggesting that SP-D facilitates physical elimination. Phase variation to evade SP-D contributes to the persistence of this common gastric pathogen.  相似文献   
6.
Pseudo-angiomatous hyperplasia of mammary stroma (PASH) is a histopathological entity which is a microscopic fortuitous finding in mammary biopsies performed for different reasons. It may be symptomatic and appears then as a palpable lump. The term pseudo-angiomatous emphasizes the characteristic aspect of the stroma simulating a vascular tumor. We report a case of PASH in a 71 year-old woman who presented a recurring breast mass with rapid swelling of the mammary gland (70 x 60 x 20 cm) treated by mastectomy. PASH must be distinguished from a well-differentiated angiosarcoma. It is ruled out by immunohistochemistry.  相似文献   
7.
One-hundred five influenza B-positive specimens obtained from southeast Asia in 2002 were categorized on the basis of DNA sequencing of HA1 gene as well as real-time PCR analysis of the NA gene. Phylogenetic analysis of the HA1 gene sequences showed that the majority of the viruses (96.2%) belonged to the B/Victoria/2/87 lineage, while a smaller percentage of the viruses (3.8%) belonged to the B/Yamagata/16/88 lineage. The B/Yamagata/16/88 viruses displayed significant antigenic drift in the deduced amino acid sequences of the HA1 protein, and the B/Victoria/2/87-like viruses consisted of B/Hong Kong/1351/02-like (72.3%) and B/Hong Kong/330/01-like (27.7%) viruses. The B/Hong Kong/1351/02-like viruses were reassortants with the HA gene belonging to the B/Victoria/2/87 lineage and the NA gene belonging to the B/Yamagata/16/88 lineage, whereas both the HA and NA genes of B/Hong Kong/330/01 virus belonged to the B/Victoria/2/87 lineage. In this study, however, all the B/Hong Kong/330/01-like isolates exhibited the B/Yamagata/16/88-like NA gene, which likely resulted from reassortment of B/Hong Kong/330/01 and B/Hong Kong/1351/02 viruses during coinfection. Additional molecular characterization of the six internal genes showed that the M, NS, PA, and PB2 genes of the new variants were B/Hong Kong/1351/02 in origin, whereas the NP and PA genes retained the B/Hong Kong/330/01 origin. Interestingly, these new variants all appeared late in the year 2002. These results support the notion that influenza B viruses continued to evolve through antigenic drift and shift.  相似文献   
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Soluble interleukin-2 receptor (sIL-2R) levels were followed up after thymectomy by a quantitative immunoradiometric assay in 59 patients with myasthenia gravis (MG). Increased levels of sIL-2R were found in 30.5% of the patients before thymectomy. Serum levels were significantly higher in severely affected patients. Sequential sampling after thymectomy indicated a significant and progressive decline of sIL-2R levels within 2 years after surgery, which was well associated with clinical improvement or remission. The sIL-2R purified from sera of patients with MG had a molecular mass of 45 kDa as the normal sIL-2R. The decline after thymectomy of sIL-2R titers suggests a possible role of the thymus in the occurrence of sIL-2R in the periphery. Soluble IL-2R levels may represent a marker of disease severity in MG, which might be useful in the follow-up of individual patients.  相似文献   
10.
The disruption of transaminases and phosphatases from the normal values denotes biochemical impairment and lesions of tissues and cellular function because they are involved in the detoxification process, metabolism and biosynthesis of energetic macromolecules for different essential function. The results of the present study revealed that feeding chicken in profenofos contaminated feed at levels of 50, 100 and 200 ppm for three weeks, resulted in a significant increase in the values of glutamic-pyruvic transaminase (GPT), glutamic oxaloacetic transaminase (GOT), Alkaline phosphatase (A.P.) and cholesterol, especially at levels of 100 and 200 ppm. Upon return of normal feed free from profenofos for 10 days, these values decreased gradually but not to normal and the decreases were not significant.  相似文献   
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