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101.
Despite some serious past efforts to clarify its multiple dimensions and meanings, access to health care has remained a rather elusive concept, hampering the work of health care policymakers and professionals as they endeavor to effect meaningful health care reform. This article provides perhaps the most detailed clarification of the access concept, especially the crucial linkages among the various access dimensions, and presents a comprehensive conceptual framework for evaluation and planning activities as they relate to people's access to health care services. The proposed conceptual model recognizes access as the outcome of a process involving the interplay between the characteristics of the health care service system and of potential users in a specified area, and moderated by health care related public policy and planning efforts. An elaborate typology of access, incorporating four pairs of access dimensions, is also derived. This atomization of the concept allows us to focus on specific aspects of the access to health care problem, and to develop precise outcome indicators of health system performance for evaluative purposes. Further, it enables the access concept and its pertinent dimensions to be put into proper perspective when assessing the health care access situation in a specific national or regional context. The relevance of the proposed access model and the typology to health care planning in general, and to spatial planning of health care service systems in particular, is also discussed.  相似文献   
102.
75-80% of the general public in Pakistan visits a private practitioner first in the case of illness. Private practitioners are therefore an important primary target for HIV/AIDS training and clinics are an ideal site in which to convey HIV prevention messages. The Physicians Forum for Family Planning in 1991 conducted a random survey of private practitioners' knowledge, attitudes, and beliefs about AIDS. 48% did not know what AIDS stands for, 68% were unaware of the meaning of HIV, none could identify all three modes of HIV transmission, 33% knew that contaminated needles can transmit HIV, and none knew about perinatal transmission. Training workshops were therefore organized to improve HIV/AIDS awareness among private practitioners, concentrating upon transmission, risk factors, clinical signs and symptoms, HIV prevention, HIV and contraception, the role of private practitioners in prevention and care, and counseling. 398 private practitioners had participated in the workshops by the end of September 1993. When pre- and post-workshop awareness were compared, correct answers had increased from 45% to 95%. It was difficult, however, to convince participants that kissing is not risky. It was also a challenge to make them understand the difference between HIV infection and AIDS. Interactive discussions and slide talks were particularly popular. Counseling on sexuality and clinical care for and counseling people with HIV/AIDS are areas for follow-up for those interested. A post-intervention evaluation in 1994 found that the workshops had a significant impact upon the clinical practice of private practitioners.  相似文献   
103.
This report responds to a resolution that asked the American Medical Association (AMA) to take action to reduce potential health risks from the use of methylcyclopentadienyl manganese tricarbonyl (MMT) in gasoline. Information for this report was derived from a search of the MEDLINE database and references listed in pertinent articles, as well as through communications with medical and public health experts. Based on this information, the AMA Council on Scientific Affairs determined that there is insufficient scientific evidence to assess the public health impact of MMT use. While limited evidence indicates that general-population exposures to manganese from the use of MMT in gasoline are low, more research is needed to determine possible health effects from long-term, low-dose exposures to MMT and its combustion products. Until such data are available, educational and informational strategies should be developed to improve public awareness of the health and environmental issues surrounding MMT use.  相似文献   
104.
105.
BACKGROUND: In unselected patients, cardiac failure accounted for most deaths after antiarrhythmic operation (ER) for postinfarction ventricular tachycardia (VT). This study aimed to determine whether patients at low risk of this outcome could be predicted from a retrospective analysis of variables from 100 consecutive ER patients. METHODS: Thirteen variables suggested by other researchers as predictive of outcome were analyzed. At the time of study, ER was the only therapy available for drug refractory VT. RESULTS: Only emergency ER, wall motion score less than 3 and Killip classification were significantly related to death from cardiac failure. The lack of correlation between emergency ER and variables of ER timing, VT less than 24 hours of ER or VT type implies that the need for emergency ER is also related to ventricular dysfunction. Multivariate analysis identified a group at particularly low risk of death with a specificity of 95%. CONCLUSIONS: Patients at low risk of death after ER can be identified prospectively. In the implantable cardioverter defibrillator era, elective ER is best reserved for such patients. Emergency ER may still be justified in younger patients without comorbidity who will die of VT without it.  相似文献   
106.
BACKGROUND: With the rapid growth of the elderly segment of the population, more octogenarians are referred for complex cardiac interventions, including reoperations. Data regarding the outcomes, quality of life, and long-term results after reoperative open-heart surgical procedures in octogenarians are scarce. METHODS: We retrospectively studied 113 consecutive octogenarians (mean age, 83+/-2.6 years) who underwent reoperative cardiac procedures within a 13-year period. Coronary artery bypass grafting (CABG) was performed in 49 patients (CABG group), valvular procedures (aortic, mitral, or tricuspid valve, alone or in combination) in 35 (valve group), and combined CABG and valve intervention in 29 (combined CABG and valve group). RESULTS: The 30-day mortality rate was 8% (4 of 49) for the CABG group, 9% (3 of 35) for the valve group, and 17% (5 of 29) for the combined CABG and valve group. One- and 5-year actuarial survival rates were, respectively, 85%+/-5% and 58%+/-10% for the CABG group, 78%+/-7% and 53%+/-12% for the valve group, and 69%+/-9% and 63%+/-10% for the combined CABG and valve group. Sixty-one percent of patients in the CABG group, 40% in the valve group, and 38% in the combined CABG and valve group were in New York Heart Association class I or II postoperatively at a mean follow-up time of 2.1+/-2.4 years. Similarly, 91%, 85%, and 80%, respectively, thought that they had an improved quality of life and were satisfied with their functional status. CONCLUSIONS: Cardiac reoperations can be performed successfully in most octogenarians, although with an increased risk, particularly in the combined CABG and valve group. Long-term survival is acceptable with improved quality of life and functional status. However, it is possible that these results could be improved in this high-risk group of patients with earlier referral and surgical intervention, for the effective use of health care resources.  相似文献   
107.
Aneurysm formation in the left ventricular outflow tract related to the proximal end of the pulmonary autograft after the Ross procedure was present in 2 patients. Both occurred late after operation and were associated with prolapse of a leaflet of the autograft and significant regurgitation. Both were repaired with no immediate complications. There was no evidence of infection at time of operation. The probable mechanisms underlying this complication and the possibilities of avoiding it are discussed.  相似文献   
108.
The effects of 0.15% quasi-steady-state end-tidal isoflurane on two saccadic eye-movement tests were examined in five volunteers using a newly devised computer-based recording system. The tests were saccadic latency and a countermanding task, the latter being an indicator of the highest levels of conscious performance. A moving light-emitting diode target was displayed on a screen and in the saccadic-latency task the latency of eye movement to the target was measured. In all five subjects the latency increased with anaesthetic by an amount which varied from 8 to 45 ms. This result was significantly different (p < 0.05) from subjects without anaesthetic. In the countermanding task, the subject had to voluntarily inhibit movement to the target. Again anaesthetic increased the latency of response, which varied from 6 to 33 ms. This result was significantly different (p < 0.05) from subjects without anaesthetic. In these studies it appeared that two tasks, one a simple latency test and the other, the countermanding task, requiring higher cortical processing were equally impaired at subanaesthetic concentrations of isoflurane.  相似文献   
109.
Urine contains several macromolecules that inhibit calcium oxalate (CaOx) crystallization. Among them is bikunin, the light chain of most of the inter-α-inhibitor (IαI) family of glycoproteins. This study aimed to verify whether bikunin and other members of the IαI family are synthesized in the kidneys or derived exclusively from the plasma. Proteins extracted from homogenized bovine kidney were applied successively to three chromatographic steps on DEAE-Sephacel, Sephacryl S-300, and Mono Q column. The inhibitory activity was assayed using a CaOx crystallization system. The presence of IαI-related proteins was determined by␣electrophoresis and Western blotting. The results showed that kidney extract contained a 125-kDa protein that cross-reacted with anti-IαI antibodies. This protein inhibited CaOx crystallization efficiently. According to its molecular weight and immunoreaction with anti-IαI antibody, the 125-kDa protein could be pre-α-inhibitor. The latter is known to encompass a heavy chain and bikunin, which may explain its inhibitory activity against CaOx crystallization. Consequently, we hypothesize that kidneys may produce some IαI-related proteins that are involved in the inhibition of stone formation. Received: 18 February 1998 / Accepted: 9 July 1998  相似文献   
110.
Household members of people with hepatitis C are at increased risk of HCV infection. The prevalence and routes of transmission of HCV to household members in Hafizabad, Pakistan were investigated. Household members of 24 index cases were given a risk factor questionnaire, tested for HCV infection, and the risk factors between the infected and uninfected were compared. Twelve of 74 household members (16.2%) were seropositive for HCV antibody. This was 2(1/2) times the rate of infection in the general population (OR = 2.8; P = 0.01). None of the routes of transmission studied within the household was associated with an increased risk. Household members who received more than 4 injections per year were 11.9 times more likely to be infected than those who had not (P = 0.016). In Hafizabad, the greatest risk for HCV infection to household members of infected people is injections given by health-care workers rather than household contact with infected persons.  相似文献   
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