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21.
A patient in chronic renal failure, who was receiving large doses of the combined alpha- and beta-blocking agent, labetalol, was selected for renal transplantation. A low concentration of halothane was used for induction and maintenance of anaesthesia, but severe myocardial depression occurred which proved unresponsive to atropine or isoprenaline, although it responded to a dopamine infusion. Synergism has already been reported between labetalol and high concentrations of halothane, but this case suggests that, in patients with previous myocardial damage, much lower concentrations of this inhalational agent may prove fatal.  相似文献   
22.
In a previous study we described a problem-based criterion-referenced test of the clinical competence of medical students which was felt to offer advantages over the traditional final-year examination. This paper reports the validity and reliability studies on which it is possible to judge the value of this new test when compared to the traditional approach.
The results demonstrate a high level of content validity and provide evidence of the construct validity of the test. Efforts to obtain measures of concurrent and predictive validity were thwarted by a failure to attain reliable assessments of ward performance from resident and consultant staff. Satisfactory levels of internal consistency were established for the whole test. Marker reliability was satisfactory in all sections of the test except for those requiring examiners to rate practical clinical skills. This was so despite the use of simulated patients, behavioural check-lists and rater training. Possible solutions to this problem are discussed.
It is concluded that this new approach overcomes many of the measurement problems inherent in the traditional final examination. It has been shown to be feasible to construct and administer in the medical school setting without the need for the allocation of additional resources.  相似文献   
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Antigen presenting dendritic cells (DCs) can serve as sites for HIV replication and as vehicles for transmission of the virus to T cells. It is known that the numbers of DCs in blood is reduced during HIV-1 infection. Here we monitored the two major subsets of blood DCs in 12 individuals undergoing a change, primarily initiation, of highly active antiretroviral therapy. The numbers of plasmacytoid DCs were reliably higher on therapy, although in the 1–3 month interval we followed, these numbers did not return to those seen in HIV uninfected controls. An increase in plasmacytoid DCs was accompanied by an increase in IFN- production in response to a standard challenge in culture with UV-inactivated herpes simplex virus. The levels of myeloid DCs also demonstrated an increase while on HAART, and these numbers become comparable to the HIV uninfected controls. The numbers of plasmacytoid and myeloid DCs varied inversely with the levels of plasma HIV viremia. These longitudinal studies extend prior work showing that virus infection with HIV leads to a decrease in the number of dendritic cells in blood, and that this can be reversed at least in part by therapy.  相似文献   
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1. Phosphoglucomutase phenotypes have been studied in several generations of the family of an individual heterozygous at each of the three loci, PGM1, PGM2, and PGM3. 2. PGM1 and PGM2 phenotypes were determined using red cells. Fibroblasts grown in tissue culture were used for PGM3 phenotyping. 3. The family results support the genetical hypothesis based on the analysis of dizygotic twin pairs that the PGM3 isozyme patterns found in the placenta are determined by two alleles, PGM13 and PGM23. 4. Locus PGM3 is not closely linked to locus PGM2 5. The data also support the previous findings that locus PGM1 is not closely linked to PGM2 or PGM3.  相似文献   
27.
Policy Points
  • Medicaid policymakers have a growing interest in addressing homelessness as a social determinant of health and driver of the potentially avoidable use of expensive medical services.
  • Drawing on extensive document reviews and in‐depth interviews in four early‐adopter states, we examined the implementation of Medicaid''s Section 1115 demonstration waivers to test strategies to finance tenancy support services for persons experiencing or at risk of homelessness.
ContextThe Affordable Care Act extended Medicaid eligibility to large numbers of individuals experiencing or at risk of homelessness. This legislative development and the growing recognition of homelessness as a significant social determinant of health have encouraged advocates and policymakers to seek new ways to use Medicaid to provide housing supports.MethodsWe conducted 28 semistructured interviews with 36 stakeholders in four states. The stakeholders were government administrators, health care providers, nonprofit housing staff, and consultants. We supplemented these interviews with extensive reviews of public documents, media accounts, think‐tank reports, and published literature. We also conducted a systematic inductive qualitative analysis.FindingsWe identified seven challenges to the successful implementation of tenancy support demonstration projects: resolving the housing supply and NIMBY, removing silos between health care and homeless services providers, enrolling and retaining the target populations in Medicaid, contracting with and paying tenancy support providers, recruiting and retaining key workers, ensuring Medicaid''s waiver durability, and reducing administrative crowd‐out and waiver burden.ConclusionsNotwithstanding these challenges, three of the four states have made significant progress in launching their initiatives. At this point, the fourth state has delayed its start‐up to consider alternatives to a Medicaid demonstration waiver to provide tenancy supports. The experience of the four states suggests lessons for Medicaid officials in other jurisdictions that are interested in pursuing tenancy support initiatives. Nevertheless, the limitations of tenancy support waiver programs suggest that federal policymakers should consider allowing states to more directly subsidize housing costs for those experiencing or at risk of homelessness as an optional Medicaid benefit.  相似文献   
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Policy Points
  • One of the most important possibilities of value‐based payment is its potential to spur innovation in upstream prevention, such as attention to social needs that lead to poor health. Screening patients for social risks such as housing instability and food insecurity represents an early step physician practices can take to address social needs.
  • At present, adoption of social risk screening by physician practices is linked with having high innovation capacity and focusing on low‐income populations, but not exposure to value‐based payment.
  • Expanding social risk screening by physician practices may require standardization and technical assistance for practices that have less innovative capacity.
ContextOne of the most important possibilities of value‐based payment is its potential to spur innovation in upstream prevention, such as attention to social needs that lead to poor health. However, there is uncertainty about the conditions under which value‐based payment will encourage health care providers to innovate to address upstream social risks.MethodsWe used the 2017‐2018 National Survey of Healthcare Organizations and Systems (NSHOS), a nationally representative survey of physician practices (n = 2,178), to ascertain (1) the number of social risks for which practices systematically screen patients; (2) the extent of practices’ participation in value‐based payment models; and (3) measures of practices’ capacity for innovation. We used multivariate regression models to examine predictors of social risk screening.FindingsOn average, physician practices systematically screened for 2.4 out of 7 (34%) social risks assessed by the survey. In the fully adjusted model, implementing social risk screening was not associated with the practices’ overall exposure to value‐based payment. Being in the top quartile on any of three innovation capacity scales, however, was associated with screening for 0.95 to 1.00 additional social risk (p < 0.001 for all three results) relative to the bottom quartile. In subanalysis examining specific payment models, participating in a Medicaid accountable care organization was associated with screening for 0.37 more social risks (p = 0.015). Expecting more exposure to accountable care in the future was associated with greater social risk screening, but the effect size was small compared with practices’ capacity for innovation.ConclusionsOur results indicate that implementation of social risk screening—an initial step in enhancing awareness of social needs in health care—is not associated with overall exposure to value‐based payment for physician practices. Expanding social risk screening by physician practices may require standardized approaches and implementation assistance to reduce the level of innovative capacity required.  相似文献   
30.

Context

In keeping with the Patient Protection and Affordable Care Act, Congress revised the law related to workplace wellness programs. In June 2013, the Departments of Treasury, Labor, and Health and Human Services passed the final regulations, updating their 2006 regulatory framework. Participatory programs that reward the completion of a health risk assessment are now the most common type of wellness program in the United States. However, legal and ethical concerns emerge when employers utilize incentives that raise questions about the voluntariness of such programs. At issue is that under the Americans with Disabilities Act (ADA) of 1990, employers cannot require health-related inquiries and exams.

Methods

To analyze the current interpretation of the ADA, I conducted research on both LexisNexis and federal agency websites. The resulting article evaluates the differences in the language of Congress''s enabling legislation and the federal departments’ regulations and how they may conflict with the ADA. It also reviews the federal government''s authority to address both the legal conflict and ethical concerns related to nonvoluntary participatory programs.

Findings

Employers’ practices and the federal departments’ regulations conflict with the current interpretation of the ADA by permitting employers to penalize employees who do not complete a health risk assessment. The departments’ regulations may be interpreted as conflicting with Congress''s legislation, which mentions penalties only for health-contingent wellness programs. Furthermore, the regulatory protections for employees applicable to health-contingent wellness programs do not apply to participatory programs.

Conclusions

Either Congress or the federal agencies should address the conflict among employers’ practices, the wellness regulations, and the ADA and also consider additional protections for employees. Employers can avoid ethical and legal complications by offering voluntary programs with positive incentives.  相似文献   
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