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81.
Greater Cape Town has developed a geographical network of perinatal health care services for low-income mothers using community-based clinics with hospital referrals. This study analyzes 25,409 births recorded in 162 different urban residential areas during 1987. The data apply to two populations--black and mixed. Information on the mother, such as height, weight, education, parity, and prenatal visits is indicated by suburb, as well as birth outcomes such as gestational age, birthweight, and method of obstetrical delivery. Comparisons are drawn between black and mixed populations and among suburbs. High utilization rates and successful maternity and infant outcomes suggest that the outreach clinics of Cape Town could provide a model for urban agglomerations in other African countries. 相似文献
82.
The public sector in Britain has been subjected to over a decade of major reform aimed at breaking up public service monopolies, at containing costs while at the same time opening services up to greater consumer choice. Health and social services have not been exempt from this revolution in the organization and management of public sector services. The long-standing policy of care in the community is being subjected to market principles and the introduction of a ‘contract culture’ very similar to the NHS reforms introduced in 1991. This paper reviews the origins of these developments in the doctrines of ‘new public management’, a movement which has proved attractive to policy-makers in many countries. Local authority social services departments have been identified as the lead agency for the development of a mixed economy of care following a review of community care policy by the government's health adviser, Sir Roy Griffiths, and a subsequent white paper. This paper examines the limited empirical evidence available on how managers and providers are meeting the challenge bestowed upon them, and concludes that most authorities are moving ahead cautiously if at all. Only a handful of authorities studied have embraced the reforms with any degree of enthusiasm. The paper concludes with an assessment of the reforms from two perspectives: a pessimistic one and an optimistic one. There are many worrying features of the reforms, not least among these being a lack of clarity over their intended purpose. Tensions and contradictions are plentiful, which places in jeopardy the certainty of the reforms in becoming user led rather than provider driven. A more optimistic scenario is that the changes are leading to a loosening up of services and practices which have often suffered from sclerotic tendencies, paternalism and sometimes complacency. If the reform process is skilfully handled and not rushed and if the ends are clearly established and communicated then users and carers could prove to be the principal beneficiaries. 相似文献
83.
84.
Limited value of technetium 99m-labeled red cell scintigraphy in localization of lower gastrointestinal bleeding 总被引:9,自引:0,他引:9
The aim of this study was to assess the accuracy of technetium 99m-labeled red cell scintigraphy in localizing the site of lower gastrointestinal bleeding. The outcome of 203 patients undergoing technetium 99m-labeled red cell scintigraphy was reviewed, and the scan result was compared with the true site of bleeding. The true site of bleeding was determined by other methods including angiography and surgical pathology. Fifty-two scans (26%) were positive and indicated a specific site of bleeding. A definitive bleeding site was identified in 22 patients by other means and correlated with the technetium scan in only 9 cases. The nuclear scan was incorrect in the remaining 13 cases, implying a localization error of 25% (13 of 52). A subgroup of 19 patients with a positive scan underwent a surgical procedure directed by the nuclear scan. Eight of these 12 patients had incorrect surgical procedures based upon findings of more definitive tests, indicating a surgical error of 42% (8 of 19). We conclude that the technetium 99m-labeled red cell scan's ability to accurately localize the site of lower gastrointestinal bleeding is limited. Furthermore, performing a surgical procedure that relies exclusively on localization by red cell scintigraphy will produce an undesirable result in at least 42% of patients. 相似文献
85.
86.
BACKGROUND—Ocular alkali burns can be associated with a poor visual outcome. The release of collagenases and proteases after the injury leads to corneoscleral melting. The role of topical steroids in such patients is controversial as they have been postulated to exacerbate corneoscleral melting.
METHODS—30 patients were reviewed retrospectively after admission to King's College Hospital with alkali burns between 1990 and 1993. All patients were treated with an intense and prolonged regimen of topical steroids and topical and systemic vitamin C.
RESULTS—22 patients had mild injuries and eight had severe injuries as estimated by the Roper-Hall grading system. 23 patients were treated with topical steroids for > 10 days and 22 patients were treated with topical vitamin C for more than 10 days. One patient with a severe injury developed corneoscleral melting.
CONCLUSION—Prolonged treatment with topical steroids when used in conjunction with topical vitamin C is not associated with corneoscleral melting.
相似文献
METHODS—30 patients were reviewed retrospectively after admission to King's College Hospital with alkali burns between 1990 and 1993. All patients were treated with an intense and prolonged regimen of topical steroids and topical and systemic vitamin C.
RESULTS—22 patients had mild injuries and eight had severe injuries as estimated by the Roper-Hall grading system. 23 patients were treated with topical steroids for > 10 days and 22 patients were treated with topical vitamin C for more than 10 days. One patient with a severe injury developed corneoscleral melting.
CONCLUSION—Prolonged treatment with topical steroids when used in conjunction with topical vitamin C is not associated with corneoscleral melting.
相似文献
87.
88.
The ureteral access set was used 43 times during an 18-month period between 1984 and 1985. Stones lodged throughout the ureter and in the renal pelvis were extracted with a success rate of 51 per cent. Of the upper tract strictures 92 per cent were dilated successfully. Filling defects were diagnosed in 88 per cent of the cases. Foreign bodies were retrieved, Double-J stents were placed and biopsies were successful in each case. Ureteral perforation in 28 per cent of the cases was caused by the dilator in 8 of 12 (19 per cent over-all). The technique and short-term results are discussed. Long-term followup data are not yet available. 相似文献
89.
P-glycoprotein expression was demonstrated in two human intestinal adenocarcinoma cell-lines (HCT-8, ileocaecal and T84, colonic) by immunoprecipitation of a 170-180 kDa protein with monoclonal antibody JSB-1. Both HCT-8 and T84 formed functional epithelial cell layers of high transepithelial electrical resistance (greater than 700 omega.cm2) when grown on permeable matrices. These epithelial layers demonstrated vectorial secretion (net vinblastine fluxes in the basal-to-apical direction of 0.135 and 0.452 pmol h-1 cm-2 in HCT-8 and T84 cell layers, respectively, from bathing solutions containing 10 nM vinblastine). These vectorial vinblastine secretions were sensitive to inhibition by verapamil. Passive transepithelial vinblastine permeation was limited by the presence of intercellular (tight) junctions, as demonstrated by the high transepithelial electrical resistance, and verapamil increased this passive vinblastine permeation concomitant with a reduction in the electrical resistance. Cellular vinblastine loading was significantly greater from the basal side, and this was also susceptible to inhibition by basal verapamil. The demonstration of vectorial transport of vinblastine in human intestinal colonic adenocarcinoma cell layers is direct evidence in favour of the hypothesis that the function of mdr1 in epithelial from the gastrointestinal tract is to promote detoxification by a process of epithelial secretion. This study also highlights that cellular vinblastine accumulation depends not only upon P-glycoprotein function, but also upon differential apparent membrane permeabilities and the presence of intercellular (tight) junctions that may restrict drug permeation and cellular accumulation to apical or basal membrane domains. 相似文献
90.
John M. Meredith Catherine J. Auger Jeffrey D. Blaustein 《Journal of neuroendocrinology》1994,6(6):639-648
Low amplitude pulses of estradiol-17β (E2-17β) are more effective than large single bolus injections or constant exposure to E2-17β in inducing progesterone-facilitated sex behavior in female rats and guinea pigs. The present study examined whether the increased responsiveness to E2-17β is due to an increase in the number of estrogen receptors in the estrogen receptor rich areas of the hypothalamus and amygdala. Initial studies examined the rapid effects (20 min) of a high dose of E2-17β (50 μg) on estrogen receptor immunostaining using either the H222 antibody or the ER 21 antiserum. ER 21 immunostaining was not affected by the E2-17β treatment suggesting that it binds to both occupied and unoccupied estrogen receptors. Therefore the ER 21 antiserum was used to characterize the regulation of estrogen receptor immunoreactivity (ER-IR) by E2-17β. ER-IR was examined for 48 h and serum E2-17β for 24 h following a 2 μg s.c. injection of E2-17β (a dose similar to that used in multiple pulse paradigms). Serum E2-17β peaked 15 to 30 min following the injection and returned to baseline values by 1 h. In all but one area maximal suppression of ER-IR occurred at 12 h. In summary, 1) decreases in estrogen receptor immunoreactivity following E2-17β are consistent with studies in which estrogen receptors were assayed by binding assays and estrogen receptor mRNA was determined by in situ hybridization; 2) the ER 21 antiserum is able to detect both occupied and unoccupied estrogen receptors and 3) H222 immunoreactivity is influenced by the presence of E2-17β, so that the level of H222-IR is a reflection of ligand/receptor binding dynamics. The data suggest that up-regulation of estrogen receptors does not account for the increase in behavioral sensitivity which is observed following multiple pulses of E2-17β. 相似文献