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1.
Purely public water supply systems are characterized by highcosts, insufficient supplies and chronic deficits that are coveredby central government transfers. The private water supply programmein Abidjan has not met its coverage targets either, but thesystem has remained financially solvent and fostered a rapidgrowth in capacity through the informal sector. The materialreviewed here and the experience of developing country watersystems in general support several conclusions. (1) Water vendingis common in developing countries, which suggests that chargingfor water is not culturally unacceptable. Demand for wastewaterservices is low, but surcharges could be imposed on water usageto cover some sanitation costs. (2) Incentives are criticalto sound management of water supply and sanitation services.They are typically part of the structure of private firms, butare rare in publicly run systems. (3) The private sector's rolein the provision of water supply and sanitation can be extensive.Regulation of private activity and quality control by publicauthorities is essential to maintain competition and ensureproper and fair operation. (4) Public efforts to supply watercan be supplemented by a government-regulated, parallel systemto increase the amount of water available. Normally these systemsinvolve trucked water, but private sales outlets with pipe infrastructureshould be encouraged where feasible. (5) Even where the publicsector decides to control and operate the water supply and sanitationsystem, some partnership with the private sector is possiblethrough contracting out specific tasks such as billing, metering,maintenance of various components or tracking water losses.Finally, the supply of water is an ideal activity for a public-privatepartnership. Both sectors have comparative advantages that arebest applied in conjunction with the other. 相似文献
2.
M. J. ANSSON B.-O. NILSSON E. ROSENGREN J. EKSTROM O. LUNDGREN 《Acta physiologica (Oxford, England)》1993,149(4):483-490
The aim of this study was to investigate to what extent polyamine metabolism in the small intestine of the rat is controlled by the enteric nervous system. Polyamine metabolism was followed by measuring the activity of ornithine decarboxylase (ODC) and in some instances also the content of polyamines (putrescine, spermidine and spermine). ODC activity in the intestine was increased when intraluminal pressure was increased and 3 h after placing cholera toxin in the intestinal lumen. Cholera toxin also increased the tissue putrescine content. Atropine or hexamethonium given i.v. did not influence the evoked changes of ODC activity. The pressure induced changes were not decreased by placing lidocaine on the serosal surface. On the other hand, the ODC activity of control segments were decreased by hexamethonium or atropine. The presence of glucose in the intestinal perfusate did not augment tissue ODC activity, neither did the heat stable enterotoxin from Escherichia coli (STa). It is concluded that the effect on polyamine metabolism evoked by luminal pressure or cholera toxin seems not to be mediated via nerves, while nerves seem to influence ODC activity during control conditions. The experiments with enterotoxins suggest that cAMP is the intracellular second messenger controlling intestinal ODC activity. 相似文献
3.
Cisapride in the treatment of post-operative ileus 总被引:2,自引:0,他引:2
B. HALLERBÄCK B. BERGMAN† H. BONG‡ P. EKSTRÖM§ H. GLISE K. LUNDGREN| O. RISBERG† 《Alimentary pharmacology & therapeutics》1991,5(5):503-511
The effect of cisapride on duration of post-operative ileus after surgery was investigated in a randomized, double-blind, placebo-controlled study. Patients undergoing elective upper gastrointestinal (n = 47) or colonic (n = 22) surgery were pre-operatively randomly allocated to treatment with either cisapride 30 mg t.d.s., by rectal administration, or placebo. Treatment started exactly 48 h after surgery if the patient at this time had not passed stool. Time to passage of first stool after surgery was estimated. Mean time to passage of stool was 85 (32) h (s.d.) for cisapride-treated and 91 (43) h for placebo-treated patients. No difference between the treatment groups was noted. Treatment with cisapride did not shorten the duration of postoperative ileus after either upper gastrointestinal or colonic surgery. 相似文献
4.
The aim of this analysis was to demonstrate the importance ofexamining the context of alcohol consumption with regard toa criminal event. The paper explores information which was partof a larger study of alcohol use by violent and non-violentoffenders. Data were collected by interview from the offendersand correlated with other reports. Earlier findings of the studywhich have been reported suggested that level of consumptionwas associated with the type of offence. In this paper a morecomplex drinking/drinking context and crime relationship isshown to exist. The circumstances at the time of the crime wererelated more to the level of alcohol consumption than to theviolent or non-violent nature of the crime. Type of beverage,companionship and time of day were found to be particularlygood indicators of the amount of alcohol consumed. 相似文献
5.
PETER R. KOWEY M.D. MICHAEL KOSLOW M.D. ROGER A. MARINCHAK M.D. TED D. FRIEHLING M.D. 《Journal of cardiovascular electrophysiology》1989,3(2):156-159
The term masquerading bundle-branch block has been used to describe a peculiar electrocardiographic abnormality in which the standard leads exhibit a left bundle-branch block pattern while the precordial leads manifest a right bundle-branch configuration. Autopsy studies of patients who have had this electrocardiographic pattern in life have shown diffuse conduction system disease, but direct recordings of conduction system function have never been reported. We recently cared for a man with masquerading bundle-branch block, and in this report we summarize the results of invasive electrophysiological testing. Our findings confirm that masquerading bundle-branch block can be associated with severe and diffuse conduction system disease, and that patients with this finding may require permanent pacemaker implantation, especially if they are symptomatic. 相似文献
6.
The effect of adrenal steroids,corticotropin, and growth hormone on resistance to experimental infections
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Cortisone acetate, hydrocortisone, and hydrocortisone acetate depress the resistance of mice to pneumococcal and influenza viral infections, although hydrocortisone acetate is somewhat less effective than the free alcohol, when given subcutaneously. Pituitary adrenocorticotropin, even in highly purified form and in oil and beeswax, does not significantly alter the resistance of mice to these experimental infections, even when given in doses which may cause profound eosinopenia, lymphopenia, and weight loss, and which are at the limit of tolerance of the animals. Corticosterone depresses resistance to pneumococcal infections significantly, but fails to alter resistance to influenza viral infections. The findings suggest that murine adrenals may produce one of the known adrenal steroids such as corticosterone along with another steroid, or may produce a steroid other than cortisone, hydrocortisone, or corticosterone. When resistance is decreased by adrenal steroids, survival time is invariably shortened, and the effect of the steroid hormones is frequently demonstrable within the 1st day after infection with pneumococci, making it unlikely that the depression of resistance that is seen is primarily due to depression of antibody formation. A single dose of 5 mg. of cortisone may cause depression of resistance and may decrease the survival time for 3 to 6 days afterward. Growth hormone (somatotropic hormone) in highly purified form, and in the doses used, did not overcome the weight loss induced by cortisone, but the animals treated with growth hormone and cortisone regained their lost weight more rapidly than those receiving cortisone alone. Growth hormone alone caused a slight increase in the rate of gain in weight over controls. Growth hormone alone did not increase resistance to infection, and did not increase the survival time, in mice infected with either pneumococci or influenza virus. Growth hormone in various dosages failed to overcome the effect of cortisone in depressing resistance to these infections. Cortisone, hydrocortisone, corticosterone, and corticotropin did not alter significantly the titers of influenza virus attained in the murine lungs during the first 2 days after infection, but cortisone and hydrocortisone markedly delayed the rate at which virus titers declined during the subsequent 6 days. Corticosterone and corticotropin delayed the rate at which the titers declined but slightly, and growth hormone had no apparent effect, as compared with controls. Growth hormone did not overcome the effect of cortisone and hydrocortisone on viral titers. No detectable antibody was found as late as 6 days after infection, in controls or in hormone-treated animals. 相似文献
7.
The pattern of axially (perpendicular to the occlusal plane) directed occlusal forces developed during light tooth tapping in habitual occlusion, chewing, swallowing and maximal biting was studied in twelve subjects whose dentitions were periodontally treated and prosthetically restored with cross-arch bridges with unilateral posterior two-unit cantilevers. The measuring devices consisted of four strain-gauge transducers uniformly and bilaterally mounted in pontics of maxillary bridges to represent the posterior (end abutment and distal cantilever respectively) and anterior regions. Thus, the forces could be studied locally in various parts of the dentition simultaneously as well as totally over the entire dentition. The results demonstrated that the distal cantilever unit, on average, was subjected to forces about or less than half of those over the contralateral end abutment unit irrespective of the activity studied. Furthermore, the cantilever forces either equalled or were even significantly smaller than those of the anterior regions. All subjects preferred the end abutment side as the chewing side. When the cantilever side was used as the chewing side, which occurred most infrequently, the bolus was usually located in the anterior region. The mean total chewing force (about 50 N) was only about half of that found in a previous study of subjects supplied with cross-arch bridges with bilateral end abutments (Lundgren & Laurell, 1985). Furthermore, on average only 26% of the voluntary muscular capacity was used during chewing, compared with 37% in the 'bilateral end abutment group' referred to. The reasons for the comparably small forces over the distal cantilever unit and the lower muscular utilization during chewing in cross-bridges with unilateral posterior two-unit cantilevers as well as the implications of the findings for the dimension of such bridge constructions are discussed. 相似文献
8.
1. Two patients, a father and his only son, suffered from a severe congenitalhemolytic syndrome, which was characterized by the presence of spontaneousinclusion bodies in erythrocytes and by the excretion of dark-brown pigmentsin the urine.2. The inclusion bodies present in approximately one-third of the erythrocytes, were indistinguishable from Heinz-Ehrlich bodies. They occurred inreticulocytes and occasionally in normoblasts. In addition to these bodies,many erythrocytes contained basophilic stippling, siderocytic granules androd-like structures. These morphologic abnormalities are believed to be theresult of an inherited metabolic abnormality of the red cells.3. The urinary pigments were found to have properties which were similarto mesobilifuscin. It is believed that these pigments possessed a dipyrrolicstructure and were derived from erythrocyte catabolism.4. Transfusion of the patients erythrocytes into a normal recipient resultedin rapid removal of the heterologous cells from the circulation and in excretion of similar dark pigments in the urine. Submitted on November 4, 1958 Accepted on November 30, 1958 相似文献
9.
JANE L. STOHLER R.N. PETER R. KOWEY M.D. ROGER A. MARINCHAK M.D. TED D. FRIEHLING M.D. 《Journal of cardiovascular electrophysiology》1987,1(6):568-574
Propafenone is a Class IC antiarrhythmic drug that has been under investigation for over 10 years and is on the threshold of release for general use. Clinical trials have been completed that present compelling evidence of the safety and efficacy of the drug for the treatment of malignant ventricular arrhythmias. As with other potent antiarrhythmic agents, propafenone has the propensity to interact with a variety of other drugs, and these interactions are of critical importance to physicians who will prescribe the drug to patients with cardiac arrhythmias. A particularly detailed knowledge of the interactions between propafenone and such commonly used drugs as anticoagulants, digoxin, cimetidine, other antiarrhythmics, and even food is essential to its safe administration. This paper reviews current information regarding the drug interactions of propafenone so that, once released and available, it will be used appropriately and safely. 相似文献
10.
GENEVIVE ESTENNE-BOUHTOU KLAS KULLANDER MAGNUS KARLSSON TED EBENDAL ULI HACKSELL KRISTINA LUTHMAN 《Chemical biology & drug design》1996,48(4):337-346
Nine low molecular weight nerve growth factor (NGF)-like peptides have been designed to mimic the putative receptor-binding epitope of NGF defined by two β-hairpin loops. Eight different spacers were used as variable links between the β-loop amino acid residues, which from mutagenesis experiments were found to play an important role in the biological activity of NGF. These spacers were amino acids, natural or non-natural, differing in length (5–13 Å) and polarity. The peptides were synthesized via the Fmoc solid-phase peptide synthesis and purified by reversed-phase HPLC. Their primary sequences were analyzed by a combination of automated Edman degradation and mass spectrometry. The peptides were tested using two different biological assays, the fibre outgrowth from chick embryonic sympathetic ganglia and the PC 12 cell differentiation assay. Weak antagonistic effects could be observed for some peptides. © Munksgaard 1996. 相似文献