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991.
Independent Practice Associations (IPAs) are the fastest growing segment of the Health Maintenance Organization (HMO) industry, but little is known about their provision of health promotion and disease prevention to subscribers. To examine the extent to which IPA policies encourage health promotion and disease prevention, we interviewed medical directors and other senior administrators of six newly developing IPA-HMOs in New York City. We also reviewed promotional literature to assess how extensively health promotion and disease prevention were marketed to the potential subscriber. Although medical protocols for preventive screening exist in most IPAs, compliance with guidelines is left largely to the individual physician's judgment for implementation. IPA respondents suggested that their physician panels are oriented toward prevention, but there is uncertain evidence in this regard, and incentive payments could discourage referrals for screening. Health education programs are sporadic. Health promotion and disease prevention do not appear to be a high priority among six newly established IPAs in New York City. We recommend several steps that would encourage IPA-HMOs to increase their health promotion activities.  相似文献   
992.
Topical dexamethasone was used to elevate rabbit intraocular pressure in order to study the interaction with a steroid antagonist, mifepristone. Dexamethasone did not cause a consistently significant increase in intraocular pressure. Animals treated with mifepristone followed by dexamethasone showed no apparent increase in intraocular pressure after dexamethasone, indeed mifepristone caused a lower intraocular pressure than seen in other groups whether in the presence or absence of dexamethasone. Reductions of intraocular pressure when mifepristone was given after 14 days of dexamethasone administration were not found. No conclusion can be reached regarding any dexamethasone antagonism by mifepristone, except that intraocular pressure tended to be lower even in the presence of dexamethasone.  相似文献   
993.
Changes in phosphorus metabolites and intracellular pH in acute liver failure induced by D-galactosamine (GAL) were evaluated non-destructively and continuously using 31P-NMR spectroscopy. Furthermore, changes in these parameters under ischemia were also examined. GAL(1.0g/kg) was injected intravenously to male Wistar rats. NMR measurements in perfused livers were performed with a GX-270FT NMR spectrometer (JEOL). Typical changes in 31P-NMR spectra were observed after GAL administration. ATP levels decreased to 57.4 +/- 12.4% at 12 hours and to 65.4 +/- 7.7% at 24 hours after the administration compared with that in control rats. Pi levels increased remarkably to 632.1 +/- 76.4% at 3 hours and recovered to 127.5 +/- 22% at 24 hours. NAD+/NADH and UDP-sugar levels gradually increased to 253.5 +/- 33.4 and 456.3 +/- 60.9%, respectively, at 24 hours. In GAL treated livers, ATP levels fell rapidly and Pi levels rose correspondingly during ischemia, and they rapidly recovered by reperfusion. The intracellular pH decreased to 7.16 +/- 0.032 from 7.38 +/- 0.065 at 3 hours after GAL administration. However, significant changes in pH were not observed until 24 hours. In GAL treated livers, slight changes in pH were observed under ischemia. These results indicate that 31P-NMR is a useful method to evaluate the damage of acute liver failure, and to diagnose liver diseases involving the intrahepatic energy metabolism.  相似文献   
994.
The authors analyze the efficacy of He-Ne laser therapy of amblyopia of various origins in 48 children (81 eyes). Group 1 children were not treated at all in order to assess the visual function background fluctuations (absolute controls). Along with He-Ne laser, used in Group 2, a 'placebo', slit lamp with blinking light, was used in Group 3. Vision acuity was assessed with the use of Sivtsev-Golovin's and Orlova's tables and by visocontrastometry in a blind test. Common visometry has shown a reliable and approximately similar improvement of the vision acuity in Groups 2 and 3 patients, whereas visocontrastometry has not detected any changes of visual function in all the 3 groups. These results cast doubt on the true efficacy of He-Ne laser stimulation of visual function, at least in children, and once again demonstrate that such investigations may be carried out only with a reliable ('blind') control and placebo.  相似文献   
995.
We successfully replanted five amputated legs in five patients and followed the patients for two years or more (average, six years and three months). Although some patients found it impossible to squat and to run because of joint contractures, muscle weakness, or deformities of the foot, all patients could perform other activities without difficulty. None had important pain or any intolerance to cold, and all were satisfied with the results of the replantation.  相似文献   
996.
Aberrometry in the diagnosis of eye diseases   总被引:1,自引:0,他引:1  
Four methods (by means of Smirnova-Korniushina's aberrometer; with the help of aberroscope--Cherning's lattice; by presenting a figure of a cross; and by automatic refractometry through different portions of the pupil) were used for studying aberration of the optic system of the eye in 490 persons. Among them, 37 were healthy persons, 27--patients with ametropia of moderate degree, 24--with high myopia, 9--with astigmatism above 3.0 D, 16--with monocular diplopia, 327--with keratoconus, 7--with scars of the cornea, 21--with initial cataract, 47--after keratotomy. In norm and in ametropia to 6.0 D, a histogram of refraction distribution by the pupil has a small disperse and a pronounced peak, the Cherning's lattice is straight. In high myopia, the disperse of refraction increases, the peak is slightly pronounced, the lattice is curved along the margins. In astigmatism, the disperse of refraction is great, but there can be peaks. The whole lattice is curved. In monocular diplopia, two more peaks can be seen on the histogram. The lattice is greatly curved. In keratoconus, aberrometry without correction is possible only at the initial stage and shows a rather mixed picture. The histogram of refraction represents a low irregular row. In aberroscopy, the bands are greatly curved, frequently overstep the bounds of the frame that itself looses a form of a circle, becomes oval or polygonal. Contact correction improves the aberration picture considerably. In scars of the cornea, the lattice is distorted and infrequently repeats their forms. In initial cataract, the course of the bands becomes interrupted and rounded spots appear between them.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
997.
As natural rubber latex (latex) has become more widespread in our environment, physicians have become increasingly aware of the problem of possible allergic reactions. Many fatal and near-fatal incidents have been reported (mainly during surgery) (1—3) and data has been published on groups frequently exposed to latex, such as patients with spina bifida (4—9), healthcare professionals (10—12) and occupationally exposed persons (13). The incidence of latex allergy in children seems to be increasing (14). Tests are therefore needed which can reliably detect sensitization to latex. Our aim was to compare the diagnostic accuracy of three commercial immunoassays for measuring specific IgE in serum to latex.  相似文献   
998.
The treatment of neoplasia with interleukin-2 (IL-2) can be complicated by neurological deficits resembling transient Ischemic attack and stroke. We investigated whether interleukin-2 contributes to the natural course of cerebrovascular ischemia and particularly to the pathogenesis of infection-associated stroke. Plasma levels of interleukin-2 were below the level of detectability in almost all measurements. Patients with and without previous infection (n = 11, 805 ±445 U/ml vs n = 19, 824 ± 501 U/ml) did not have significantly higher levels of soluble interleukin-2 receptors than control subjects with (n = 14, 667 ± 229 U/ml) or without vascular risk factors (n = 17, 567 ± 176 U/ml). Receptor levels increased in patients during the first week after stroke (n = 15, 1157 ± 1013, p < 0.02). Levels of soluble T8 antigen (sT8) were higher in patients (n – 26, 320 ± 112 U/ml) than in healthy control subjects (n = 15, 246 ± 92 U/ml; p < 0.05) and sT8 levels increased during the first week after stroke (p < 0.05). These results reflect an immunological response to the cerebral infarct; they do not indicate a general role of the IL-2 system in the pathogenesis of ischemic stroke with or without previous infection.  相似文献   
999.
This paper concerns the diagnostic classification of nonaffective acute remitting psychosis (NARP), which we also term acute brief psychosis. We argue that NARP can be delineated from both schizophrenia and the affective psychoses and considered as a single diagnosis. As indicated by the term NARP, four criteria would be central to the diagnosis: 1. nonaffective, 2. acute onset (over less than two weeks), 3. recovery within a brief duration (less than six months), and 4. psychosis broadly defined. We review the rationale and the empirical evidence for this proposed classification.  相似文献   
1000.
Computer simulations of bone remodeling in response to mechanical stresses can be used to understand normal growth and development of the skeleton or to predict the remodeling of bone in response to prosthetic devices. Using a previously derived bone maintenance theory, a technique for computing bone density distributions was applied to the proximal femur and tibia using two-dimensional, multiple-loading finite element models. The models initially represented solid, homogeneous structures. Using an iterative bone remodeling technique that relates bone apparent density to loading history, the internal distributions of apparent density and elastic modulus for the normal bones were predicted. The finite element models were then modified to represent bones in which porous-coated femoral surface replacements and tibial tray components had been implanted. The same iterative remodeling method was then applied to predict the distribution of bone around these components. The predicted bone density distributions for the natural femur and tibia agree with previously documented normal bone morphology. The predicted bone density distributions around various implanted prostheses were characteristic of the component under investigation and were consistent with clinical and experimental findings of other investigators. In the femoral head, stress shielding occurred underneath the metal surface replacement cup, resulting in lower densities in the femoral head. The addition of a central femoral cup fixation peg caused bone hypertrophy around the peg. In the tibia, the stress concentrations around the pegs also resulted in denser bone, with a concomitant decrease in bone density at more peripheral locations underneath the prosthetic tray. This remodeling technique has the potential to be an important tool in predicting the possible remodeling consequences of new implant design features.  相似文献   
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