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31.
第3产程,即从胎儿娩出开始到胎盘娩出,是分娩的最后阶段,其自然进程包括脐带搏动停止,胎盘从子宫壁剥离和胎盘通过产道。失血量的多少取决于胎盘从宫壁剥离的时间和产后初期子宫的有效收缩能力。 相似文献
32.
BRUCE B. LERMAN KENNETH M. STEIN STEVEN M. MARKOWITZ 《Pacing and clinical electrophysiology : PACE》1996,19(12):2120-2137
Right ventricular outflow tract (RVOT) tachycardia is the most common form of idiopathic ventricular tachycardia (VT). Phenotypically, RVOT tachycardia segregates into two predominant forms, one characterized by repetitive monomorphic nonsustainnd VT and the other by paroxysmal exercise induced sustained VT. There is an increasing body of evidence to support the concept that both forms of tachycardia reflect disparate clinical manifestations of an identical cellular mechanism (i.e., cAMP-mediated triggered activity), which is identified clinically by the tachycardia's sensitivity to adenosine. The clinical characteristics, natural history, and approaches to therapy of RVOT tachycardia are delineated herein. 相似文献
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IAN LOVETT STEVEN DONCHEY BRUCE DOUST JOHN BRANSON VINCENT MUNRO 《Journal of Medical Imaging and Radiation Oncology》1989,33(2):124-127
The water soluble contrast agents GastrografinR (Sodium diatrizoate and meglumine diatrizoate, Schering, Berlin), Iopamiro 300 R (Iopamidol, Schering, Berlin), and Dionosil AqueousR (propyliodone BP, Glaxo, England) were instilled into the tracheobronchial tree of rats in doses of either 0.1 ml and 0.25 ml. Rats being used as controls, underwent sham operations with the instillation of air instead of contrast agent. In all, 85 rats were used. All rats that had not already died from the effects of contrast agent were sacrificed 30 minutes after instillation. The relative effects of the contrast agents were measured by comparing: 1. survival time; 2. radiographic effects of the contrast agents on the lungs and; 3. pathological changes as estimated by post mortem lung section andmicroscopy. The least toxic agent was the one with the lowest osmotic activity, namely Aqueous Dionosil. It is therefore recommended that Aqueous Dionosil be used in preference to Gastrografin or Iopamidol for studies of the oesophagus whenever there is a danger of aspiration of contrast agent into the tracheobronchial tree. 相似文献
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R. STAUGAS A. J. MARTIN G. BINNS I. M. STEVEN 《Journal of paediatrics and child health》1985,21(4):275-277
Tracheal aspirates from 46 children were examined for the presence of fat-filled macrophages. They had no history suggestive of gastro-oesophageal reflux. The number of positive results from this group (46%) was compared with the number of positive results (73%) in a group of 40 children with proven gastro-oesophageal reflux. The difference in proportion of positive results between the two groups was statistically significant ( P <0.05). In addition, subgroups of subjects, negative for gastro-oesophageal reflux and lower respiratory tract disease, were compared with children who had both conditions. A slightly greater difference, although at a similar level of significance, was found. The fact that 42% of subjects without lower respiratory tract disease or gastro-oesophageal reflux had tracheal aspirates positive for fat-filled macrophages would, however, suggest that this test is of limited clinical value and may need better quantitation before it can be recommended for widespread clinical use. 相似文献
37.
Context: Counseling smokers to quit smoking and providing them with pharmaceutical cessation aides are among the most beneficial and cost‐effective interventions that clinicians can offer patients. Yet assistance with quitting is not universally covered by health plans or offered by all clinicians. Analysis of stakeholders' perspectives and interests can identify the barriers to more widespread provision of cessation services and suggest strategies for the public policy agenda to advance smoking cessation. Methods: Review of literature and discussions with representatives of stakeholders. Findings: All stakeholders—health plans, employers, clinicians, smokers, and the government—face barriers to broader smoking cessation activities. These range from health plans' perceiving that covering counseling and pharmacotherapy will increase costs without producing commensurate health care savings, to clinicians' feeling unprepared and uncompensated for counseling. Like other preventive measures aimed at behavior, efforts directed at smoking cessation have marginal status among health care interventions. State governments can help correct this status by increasing Medicaid coverage of treatment and expanding coverage for state employees. The federal government can promote the adoption of six initiatives recommended by a government subcommittee on cessation: set up a national quit line, develop a media campaign to encourage cessation, include cessation benefits in all federally funded insurance plans, create a research infrastructure to improve cessation rates, develop a clinician training agenda, and create a fund to increase cessation activities through a new $2 per pack cigarette excise tax. Both the federal and state governments can increase cessation by adopting policies such as the higher cigarette tax and laws prohibiting smoking in workplaces and public places. Conclusions: Public policy efforts should assume greater social responsibility for smoking cessation, including more aggressive leadership at the state and federal levels, as well as through advocacy, public health, and clinician organizations. 相似文献
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F. REED JOHNSON JUAN MARCOS GONZALEZ JUICHEN YANG SEMRA OZDEMIR STEVEN KYMES 《The Milbank quarterly》2021,99(3):771
Policy Points
- Public funding for mental health programs must compete with other funding priorities in limited state budgets.
- Valuing state‐funded mental health programs in a policy‐relevant context requires consideration of how much benefit from other programs the public is willing to forgo to increase mental health program benefits and how much the public is willing to be taxed for such program benefits.
- Taxpayer resistance to increased taxes to pay for publicly funded mental health programs and perceived benefits of such programs vary with state population size.
- In all states, taxpayers seem to support increased public funding for mental health programs such as state Medicaid services, suggesting such programs are underfunded from the perspective of the average taxpayer.
40.
STEVEN S. WITKIN 《American journal of reproductive immunology (New York, N.Y. : 1989)》1988,17(2):61-64
ABSTRACT: The production of autoantibodies to spermatozoa in males and isoantibodies in females is inhibited both by the physical isolation of spermatozoa from the systemic immune system and by active immunosuppression mechanisms. Lymphoid cells present in the epithelial lining of the rete testis, epididymis, and vas deferens, as well as the human ejaculate, are predominantly T suppressor/cytotoxic cells. Mononuclear cells derived from semen inhibit the in vitro activation of peripheral blood lymphocytes. Soluble specific T suppressor/cytotoxic cell activators in semen or on the sperm surface may be responsible for the predominance of this T cell subset in the male reproductive tract. The activation of T suppressor/cytotoxic cells following coitus may also limit the immune response to spermatozoa in females. Spermatozoa can also initiate immunosuppression, either by selectively inducing T suppressor cells or through the generation of activated complement components that block antibody production. Antisperm antibodies in sera from females may be associated with either a deficiency in the ability of their T suppressor/cytotoxic cells to be induced by factors in semen or by the occurrence in their husbands' ejaculates of microorganisms, antibodies, or other factors that induce T helper lymphocytes. Activated T cells produce interferon gamma, which induces Ia antigen expression on macrophages and allows the female's T helper cells to recognize processed sperm antigens. Recognition of the role of cell-mediated immune functions in the male and female genital tract identifies possible new target sites for the development of contraceptive agents. 相似文献