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991.
A prospective weekly home surveillance study was undertaken to determine morbidity patterns within the Butajira Rural Health project in central Ethiopia. Overall prevalence of illness was 5.8% in 1216 person-years observed among rural Ethiopian children aged under 5 years. Acute respiratory infections (ARI) (prevalence 2.8%) and acute diarrhoea (2.4%) were the commonest conditions. Episodes of illness were distributed unequally among children, with a mean of 2.34 episodes per child. These included an average of 1.13 episodes of ARI (of which 0.16 had lower respiratory symptoms [ALRI]) and 1.17 episodes of acute diarrhoea. Sanitation factors were the principal risks for gastroenteritis, while living in rural areas predisposed children to ARI. Parental factors such as illiteracy were also linked to morbidity.  相似文献   
992.
In this study we have examined (1) the integrated function of the mitochondrial respiratory chain by polarographic measurements and (2) the activities of the respiratory chain complexes I, II-III, and IV as well as the ATP synthase (complex V) in free mitochondria and synaptosomes isolated from gerbil brain, after a 30-min period of graded cerebral ischaemia. These data have been correlated with cerebral blood flow (CBF) values as measured by the hydrogen clearance technique. Integrated functioning of the mitochondrial respiratory chain, using both NAD-linked and FAD-linked substrates, was initially affected at CBF values of approximately 35 ml 100 g-1 min-1, and declined further as the CBF was reduced. The individual mitochondrial respiratory chain complexes, however, showed differences in sensitivity to graded cerebral ischaemia. Complex I activities decreased sharply at blood flows below approximately 30 ml 100 g-1 min-1 (mitochondria and synaptosomes) and complex II-III activities decreased at blood flows below 20 ml 100 g-1 min-1 (mitochondria) and 35-30 ml 100 g-1 min-1 (synaptosomes). Activities declined further as CBF was reduced below these levels. Complex V activity was significantly affected only when the blood flow was reduced below 15-10 ml 100 g-1 min-1 (mitochondria and synaptosomes). In contrast, complex IV activity was unaffected by graded cerebral ischaemia, even at very low CBF levels.  相似文献   
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995.
Diastolic heart failure, in the absence of LV systolic dysfunction, is a common clinical condition that can be demonstrated in as many as one third of patients with congestive heart failure. Diastolic dysfunction caused by abnormalities in LV filling can be a result of many pathologic conditions, including hypertrophy, infiltrative cardiomyopathies, or myocardial ischemia. The major physiologic determinants of LV filling can be divided into cellular mechanisms, hemodynamic characteristics, and hormonal influences. Cellular mechanisms for impaired LV inactivation are determined by the handling of calcium within the myocyte during excitation-contraction-relaxation coupling. The hemodynamic characteristics of LV diastolic filling are determined by loading conditions, the time constant of isovolumic relaxation, heart rate, ventricular nonuniformity, pericardial restraint, myocardial elasticity, chamber compliance, and coronary blood flow. The sympathetic nervous system and the renin-angiotensin system are important modulators of diastolic filling, directly or indirectly. The diagnosis of heart failure is confirmed by a combination of clinical tests including invasive and noninvasive techniques, each of which has advantages and disadvantages. Treatment of medical conditions in which diastolic heart failure is a prominent component include pharmacotherapy with calcium channel antagonists, beta-adrenergic blocking agents, diuretic agents, and angiotensin-converting-enzyme inhibitors. Certain conditions associated with diastolic filling abnormalities such as pericardial disease or severe ischemic heart disease may be best managed by surgical or percutaneous intervention. Future research will include further delineation of the cellular mechanisms of active myocardial relaxation and clinical investigation into treatment directed at improving outcome.  相似文献   
996.
With regard to its chemical structure, methcathinone is to cathinone what methamphetamine is to amphetamine. Although it is a drug of abuse outside the United States, methcathione is only recently making an appearance on the clandestine market in this country and has just been classified a Schedule I substance under the Emergency Scheduling Act. We have previously demonstrated that racemic methcathinone produces locomotor stimulation in mice, and substitutes for cocaine and (+)amphetamine in rats trained to discriminate either cocaine or (+)amphetamine, respectively, from saline in tests of stimulus generalization. Because an enantiomeric potency comparison has never been reported for the optical isomers of methcathinone, in the present investigation we synthesized samples of S(-)- and R(+)methcathinone and compared them for their ability: a) to produce locomotor stimulation in mice, b) to elicit cocaine-like responding in rats trained to discriminate 8.0 mg/kg of cocaine from saline vehicle, and c) to elicit (+)-amphetamine-appropriate responding in rats trained to discriminate 1.0 mg/kg of (+)amphetamine from saline vehicle. S(-)Methcathinone was about twice as potent as S(+)amphetamine and three to five times more potent than R(+)methcathinone in the three pharmacologic assays. We conclude that both optical isomers possess central stimulant character, but that S(-)methcathinone is somewhat more potent than R(+)methcathinone.  相似文献   
997.
We measured gluconeogenesis (GNG) in rats by mass isotopomer distribution analysis, which allows enrichment of the true biosynthetic precursor pool (hepatic cytosolic triose phosphates) to be determined. Fractional GNG from infused [3-13C]lactate, [1-13C]lactate, and [2-13C]glycerol was 88 +/- 2, 89 +/- 3, and 87 +/- 2%, respectively, after 48 h of fasting. [2-13C]Glycerol was the most efficient label and allowed measurement of rate of appearance of intrahepatic triose phosphate (Ra triose-P), by dilution. IV fructose (10-15 mg/kg/min) increased absolute GNG by 81-147%. Ra triose-P increased proportionately, but endogenous Ra triose-P was almost completely suppressed, suggesting feedback control. Interestingly, 15-17% of fructose was directly converted to glucose without entering hepatic triose-P. IV glucose reduced GNG and Ra triose-P. 24-h fasting reduced hepatic glucose production by half, but absolute GNG was unchanged due to increased fractional GNG (51-87%). Reduced hepatic glucose production was entirely due to decreased glycogen input, from 7.3 +/- 1.8 to 1.1 +/- 0.2 mg/kg/min. Ra triose-P fell during fasting, but efficiency of triose-P disposal into GNG increased, maintaining GNG constant. Secreted glucuronyl conjugates and plasma glucose results correlated closely. In summary, GNG and intrahepatic triose-P flux can be measured by mass isotopomer distribution analysis with [2-13C]glycerol.  相似文献   
998.
OBJECTIVE: To study the effectiveness of combining DNA ploidy and the blood-group related membrane antigen Tn as bladder tumour markers which have been individually associated with high tumour grade and poor prognosis. In particular to (i) determine whether use of these two markers would improve tumour detection compared with either alone, particularly of high grade disease and (ii) determine whether intermediate rates of marker expression would occur in bladder cancer patients with no current tumour compared with those with a tumour and a control group with benign prostatic hypertrophy. PATIENTS AND METHODS: A total of 102 patients undergoing cystoscopic monitoring for either benign prostatic hyperplasia (BPH) or for transitional cell carcinoma (TCC) at the Repatriation Hospital and Flinders Medical Centre were included in the study. The patients comprised three study groups, those with BPH (n = 37), with TCC but no tumour present (n = 38) and those with TCC and a tumour present at cystoscopy (n = 27). Exfoliated cells obtained from bladder washings at cystoscopy were double-labelled using a monoclonal antibody to the Tn antigen and a DNA stain, propidium iodide and examined by flow cytometry. RESULTS: Rates of marker expression in 27 patients with tumours were 30% for Tn antigen, 30% for aneuploidy and 48% for either marker. Marker expression was strongly associated with tumour grade, with no expression at grade 1, 38% (3/8) tumours at grade 2 and 90% (9/10) at grade 3. In patients with a history of bladder tumours but no current tumour, rates were intermediate (30%) compared with patients with current transitional cell carcinoma (42%) and control patients (19%). CONCLUSION: The use of Tn antigen combined with DNA flow cytometry can increase tumour detection, particularly of high grade, aggressive disease. Gradation of expression of these markers across patient groups at increasing risk of a tumour, with intermediate expression in patients with no current tumour, suggests that marker expression may be detecting a preneoplastic stage of the disease, which is not possible with cytology. Given two parallel disease processes for superficial papillary and for high grade disease with invasive potential, the expression of high grade tumour markers in cells from cystoscopically normal bladders may represent a pre-clinical stage of aggressive disease. The identification of patients at risk of invasive disease using combinations of tumour markers may offer advantages in clinical management, particularly when no tumour is present and therefore no histopathological assessment is made.  相似文献   
999.
136 1-yr-old infants were tested on tasks of visual–tactual cross-modal transfer and tactual intramodal processing. In Exp I, Ss successfully differentiated novel from familiar objects by tactual exploration after 60 sec of either visual familiarization (V–T) or 60 sec of tactual familiarization (T–T); all testing that involved tactual exploration was carried out in total darkness, using infrared videotaping. In both tasks, Ss spent significantly more time manipulating novel than familiar shapes. In the T–T task they also engaged in more manipulatory episodes and exhibited more hand-to-hand transfers with the novel shapes. Neither type of transfer was shown with shorter (30-sec) familiarization periods. The finding of successful T–T transfer with 60-sec familiarization was confirmed in Exp II using different stimuli and a modified testing procedure. In both experiments there was evidence that T–T processing surpassed V–T transfer. (23 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
1000.
Investigated in 4 studies with 101 infants 25.5–32 wks of age the ability of Ss to transfer information about shape across modalities. Ss were familiarized either orally or tactually and then tested for visual recognition memory. In Exp I, Ss failed to show evidence of cross-modal transfer on any of the tasks (1 oral–visual, 2 tactual–visual). When familiarization times were increased from 30 to 60 sec in Exp II, Ss showed evidence of transfer on both tactual–visual tasks. Exp III eliminated the 5–7 sec delay that generally intervenes between the familiarization and test phase. Ss were permitted to retain the stimulus in their hand (or mouth) during the test phase while simultaneously viewing a novel stimulus and a duplicate of the familiar stimulus. This modification resulted in successful transfer on 1 of the 2 tactual–visual tasks. Ss did not show evidence of transfer on the oral–visual problem in any of these studies, despite evidence from Exp IV that they could visually discriminate the paired stimuli used in these tasks and that they showed recognition memory when familiarization and testing were both visual. Results suggest that, although cross-modal transfer of information about shape is present among 6-mo-olds, it is a less robust phenomenon than that seen in older infants. (16 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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