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At sites of purinergic neurotransmission, synaptic ecto-ATPase is believed to limit the actions of ATP following its neural release. However, details of the modulation by this enzyme of the ATP-mediated conductance change and the possible mechanisms mediating this modulation remain unelucidated. We have addressed these issues by studying the effect of ARL 67156, a selective ecto-ATPase inhibitor, on ATP-mediated electrical and contractile activity in the sympathetically innervated guinea-pig vas deferens. ARL 67156 at 100 μ m significantly potentiated the amplitude of spontaneous excitatory junction potentials (SEJPs) by 81.1% ( P < 0.01) and prolonged their time courses (rise time by 49.7%, decay time constant by 38.2%; P < 0.01). Moreover, the frequency of occurrence of SEJPs was strikingly increased (from 0.28 ± 0.13 to 0.90 ± 0.26 Hz; P < 0.01), indicating an additional, primarily presynaptic, effect of ecto-ATPase inhibition. The frequency of occurrence of discrete events (DEs), which represent nerve stimulation-evoked quantal release of neurotransmitter, was also increased (∼6-fold; P < 0.01), along with the appearance of DEs at previously 'silent' latencies. Purinergic contractions of the vas deferens were potentiated significantly ( P < 0.01) by ARL 67156; these potentiated contractions were suppressed by the A1 agonist adenosine ( P < 0.01) but left unaffected by the A1 antagonist 8-phenyltheophylline (8-PT). Our results indicate (i) that ecto-ATPase activity, in addition to modulating the ATP-mediated postjunctional conductance change, may regulate transmitter release prejunctionally under physiological conditions, and (ii) that the prejunctional regulation may be mediated primarily via presynaptic P2X, rather than A1, receptors.  相似文献   
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A total of 121 uropathogenic Pseudomonas aeruginosa strains were examined for production of several virulence-related factors. These strains were distributed in five predominant O-serotypes, i.e. O 4, O 12, O 11, O 6 and O 5, which accounted respectively for 23.9, 23.1, 12.3, 8.2 and 5.7% of isolates. Pyochelin and pyoverdin siderophores were produced by most of the isolates, defective variants occurring at very low frequency (2.4% for pyochelin and 7.4% for pyoverdin). Adherence to uroepithelial cells and production of cytotoxins was demonstrated in 52.8 and 67.7% of the strains, respectively, with higher frequencies for epidemiologically related strains belonging to serotypes O 4 and O 12. Titration of total proteases, elastase and phospholipase C revealed a high degree of heterogeneity among isolates. However, examination of individual O-serotypes by exoenzyme production showed that elevated levels of total proteases and elastase were characteristics of serotypes of minor numerical importance, i.e. O 1, O 10, O 11 and O 17, whilst low levels of elastase were produced by strains belonging to the predominant serotypes, namely O 4 and O 12. Moreover, epidemiologically related strains belonging to serotypes O 4 and O 12 appeared more homogeneous than the whole serogroup, when compared with other groups on the basis of exoenzyme levels.  相似文献   
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Transient osteoporosis is an infrequent condition of uncertain etiology with pain, limited range of motion and radiographic evidence of osteoporosis affecting one or more joints. It is self-limited, reversible and can involve only the hip (transient osteoporosis of the hip, TOH) or, less frequently, one or more joints contemporaneously or at different times (regional migratory osteoporosis, RMO). We studied four men with transient osteoporosis, including two with TOH and two with RMO. All patients underwent a standard radiographic work-up of the affected joints, arteriovenous Doppler US, computed tomography, magnetic resonance imaging (MRI) and three-phase bone scanning. In all patients, symptoms were related to bone marrow edema demonstrated at MRI and to a transitory regional arterial hyperflow observed at the early scintigraphic analysis. On the basis of our observations, we hypothesize that regional arterial hyperflow may be the cause of the bone marrow edema and therefore of the transient osteoporosis.  相似文献   
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Lipoprotein (a) (Lp(a)) and other lipid values have been correlated with angiographically defined [table: see text] coronary artery disease. To study this relationship in Indian patients, plasma levels of Lipoprotein (a) and other lipids were assessed in 74 patients undergoing Coronary arteriography and also in 53 age and sex matched healthy male blood bank donors who served as controls. Total cholesterol (mg/dl) (211 +/- 56 vs 186 +/- 43; p < 0.001), low density lipoprotein Cholesterol (mg/dl) (117 +/- 40 vs 88 +/- 29; p > 0.001) and low density lipoprotein/high density lipoprotein cholesterol ratio (2.6 +/- 0.8 vs 2.2 +/- 0.9; p < .001) were significantly higher in patients than controls. High density lipoprotein-cholesterol (mg/dl) (43.5 +/- 6 vs 42.1 +/- 7; p-ns) very low density lipoprotein-cholesterol (mg/dl) (49.7 +/- 17 vs 56.1 +/- 25; p-ns) and triglycerides (mg/dl) (155 +/- 101 vs 167 +/- 88; p-ns) were not statistically different in two groups. Lipoprotein (a) levels showed highly skewed distribution. Patients (n = 74) showed almost five fold higher lipoprotein (a) levels (mg/dl) as compared to controls (n = 53) [105 +/- 565 vs 23 +/- 76]. Patients with very high lipoprotein (a) levels [values of more than 40 mg/dl] (n = 18) had high density lipoprotein cholesterol and total cholesterol significantly lower than rest of the patient group. [high density lipoprotein cholesterol (mg/dl) 41.00 +/- 3.7 vs 44 +/- 6.4; p < 0.01 and total cholesterol (mg/dl) 192 +/- 34 vs 217 +/- 53; p < 0.05].  相似文献   
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Despite efforts to promote infant and young child feeding (IYCF) practices, there is no collective review of evidence on IYCF enablers and barriers in India. This review was conducted using 2015 Preferred Reporting Items for Systematic reviews and Meta-Analysis (PRISMA) guidelines. Six computerized bibliographic databases, Scopus, PubMed, PsycINFO, CINAHL, Embase, and Ovid MEDLINE, were searched for published studies on factors associated with IYCF practices in India from 1 January 1993, to 30 April 2020. IYCF practices examined were early initiation of breastfeeding, exclusive breastfeeding, continued breastfeeding at one year, introduction to solid semi-solid or soft foods, minimum dietary diversity, minimum meal frequency, minimum acceptable diet, continued breastfeeding at two years, predominant breastfeeding, and bottle feeding. In total, 6968 articles were retrieved, and 46 studies met the inclusion criteria. The common enablers of IYCF were higher maternal socioeconomic status (SES) and more frequent antenatal care visits (ANC) (≥3). Common barriers to IYCF practices were low SES and less frequent ANC. The review showed that the factors associated with IYCF practices in India are largely modifiable and multi-factorial. Improving IYCF practices would require the adoption of both facilities- and community-based policy interventions at the subnational and national levels in India.  相似文献   
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Quality of Life Research - Routine Electronic Monitoring of Health-Related Quality of Life (HRQoL) (REMOQOL) in clinical care with real-time feedback to physicians could help to enhance...  相似文献   
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Body growth was studied in 32 subjects with vesicoureteric reflux (VUR), diagnosed following the prenatal finding of urinary tract dilatation, who had normal renal filtration function and who received antibacterial prophylaxis by the first few days of life. They were followed for 1–5 years (mean 2.3 years). Most had persistent VUR during the 1st year of life. Body growth performance was compared with that of 94 subjects with VUR diagnosed and treated by us after the neonatal period. During the follow-up period, none of the patients with prenatally detected VUR had a height Z score below –2, nor a weight-for-height index below 90%, and 1 had variations in height Z score ≥1. The difference in the percentage of patients with prenatally detected VUR (1/32) and those with VUR diagnosed and treated after the neonatal period (20/94) who had variations in height Z score ≥1 was significant (P=0.035). Patients with prenatally detected VUR and normal renal filtration function, given antibacterial prophylaxis by the first few days of life, have normal body growth, although VUR still persists. Received: 19 March 1998 / Revised: 10 February 1999 / Accepted: 10 February 1999  相似文献   
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