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41.
Private financing for long-term care now comes almost exclusively from out-of-pocket payments. Long-term-care costs quickly impoverish most elderly, resulting in Medicaid dependency. The consequences are profound for the western Sun Belt with its rapidly growing elderly population. Key private financing options are long-term-care individual retirement accounts (LTC/IRAs), home equity conversion, social-health maintenance organizations and long-term-care insurance. Study of data from the past half century suggests that the LTC/IRA approach would prove unsatisfactory for the purpose despite the intuitive appeal of this mechanism. Experience with home equity conversions is still very limited, and unresolved questions limit this approach to the role of a reserve option for now. While promising, social-health maintenance organizations are still in the experimental stages and not yet commercially available. Long-term-care insurance is currently sold on a thin market and emphasizes nursing home coverage. New approaches to private financing through long-term-care insurance seem to offer the best approach for immediate implementation.  相似文献   
42.
Bromocriptine administration in the form of slow-release injections to male blue foxes during March-May abolished the normal spring rise in plasma prolactin concentrations seen in May and June. The spring moult was prevented and the treated animals retained a winter coat of varied quality and maturity until the end of the study in August. Plasma testosterone concentrations fell normally from March until August. Testicular regression was, however, delayed, although there were individual variations in response. Estimation by DNA flow cytometry in early July of the relative numbers of haploid, diploid and tetraploid cells in the testis showed that, in the treated animals, 74-80% of the cells were haploid (maturing germinal cells), 4-6% tetraploid (mainly primary spermatocytes) and the rest diploid cells (somatic cells and the remaining germinal cell types). In the control males, however, no haploid cells were detected and the majority of cells were diploid (93-99%). At castration in August, histological examination revealed various stages of testicular regression in the treated and control animals.  相似文献   
43.
The chloromethyl ketone derivative of D-Ala2-Leu5-enkephalin was synthesized in a radioactive form, and the resulting compound (3H-DALECK) was used to label opioid receptors. 3H-DALECK binds with high affinity, specificity and saturability to rat brain membranes. The number of sites labeled is 130 fmoles/mg protein. Unlabeled opioids inhibited the binding of 3H-DALECK; etorphine and DAGO being most potent. A 10-fold preference for mu sites over delta was seen in site-specific competition experiments; while DALECK displayed low affinity for kappa sites of rat brain. DALECK irreversibly blocked a certain population of sites. Approximately 40% of 3H-DALECK binding at 15 min, and 60% at 60 min association time did not dissociate in the presence of a large excess of unlabeled DALECK and was resistant to washing. Autoradiography performed after SDS-PAGE revealed specific alkylation of proteins with molecular weight of 74, 65, 56, 43 and 34 kD. These results demonstrate the applicability of using 3H-DALECK to covalently label opioid receptors.  相似文献   
44.
A Louilot  M Le Moal  H Simon 《Life sciences》1987,40(20):2017-2024
Buspirone is a non-benzodiazepine drug with anxiolytic properties. It has been reported to induce a marked increase in the metabolism of dopamine in the striatum and the nucleus accumbens which is similar to that induced by neuroleptics. It has been suggested that the effect observed in the striatum reflects an action of buspirone on dopaminergic autoreceptors in both terminals and cell bodies. In the present study, presynaptic effects of buspirone on dopaminergic metabolism in the nucleus accumbens were investigated, and they were compared to the effects of the classical neuroleptic, haloperidol. Dopaminergic terminals were isolated by infusion of tetrodotoxin into the median forebrain bundle in order to evaluate the effects of buspirone and haloperidol on presynaptic receptors. Changes in dopamine metabolism were determined by in vivo voltammetry. Buspirone administered after interruption of the impulse flow did not affect dopamine metabolism. In contrast haloperidol treatment led to an increase in metabolism of dopamine. It is concluded that buspirone did not act at the presynaptic level and furthermore on dopaminergic autoreceptors.  相似文献   
45.
This study was essentially an in vivo protection experiment designed to test further the hypothesis that stress induces release of endogenous opioids which then act at opioid receptors. Rats that were either subjected to restraint stress for 1 hr or unstressed were injected ICV with either saline or 2.5 micrograms of beta-funaltrexamine (beta-FNA), an irreversible opioid antagonist that alkylates the mu-opioid receptor. Twenty-four hours later, subjects were tested unstressed for morphine analgesia (tail-flick assay) or were sacrificed and opioid binding in brain was determined. [3H]D-Ala2NMePhe4-Gly5(ol)enkephalin (DAGO) served as a specific ligand for mu- opioid receptors, and [3H]-bremazocine as a general ligand for all opioid receptors. Rats injected with saline while stressed were significantly less sensitive to the analgesic action of morphine 24 hr later than were their unstressed counterparts. Beta-FNA pretreatment attenuated morphine analgesia in an insurmountable manner. Animals pretreated with beta-FNA while stressed were significantly more sensitive to the analgesic effect of morphine than were animals that received beta-FNA while unstressed, consistent with the hypothesis that stress induces release of endogenous opioids that would protect opioid receptors from alkylation by beta-FNA. beta-FNA caused small and similar decreases in [3H]-DAGO binding in brain of both stressed and unstressed animals. Stressed rats injected with saline tended to have increased levels of [3H]DAGO and [3H]-bremazocine binding compared to the other groups. This outcome may be relevant to the tolerance to morphine analgesia caused by stress.  相似文献   
46.
47.
Transformation of chicken embryo fibroblasts by avian retroviruses induces the tyrosine phosphorylation of a 34-39 kD cellular protein (p34). In vitro, p34 isolated from intestine interacts with F-actin in a Ca2+-dependent manner. We report here that, in the absence of Ca2+ chelators, three proteins co-purified with p34 extracted from a cytosolic or membrane fraction of chicken embryo fibroblasts; these two fractions account respectively for 10-20% and 50% of the total cellular p34. Isolated from the cytosoluble fraction of fibroblasts by sucrose gradient centrifugation and hydrophobic chromatography, p34 and the other proteins behaved as a homogeneous species upon non-denaturing gel electrophoresis, gel filtration, and CsCl density gradient centrifugation, thus indicating a strong association. Moreover, an analysis by electron microscopy following uranyl acetate staining revealed particles with a raspberry-like shape. This association was always disrupted by the calcium-chelating agent, EGTA.  相似文献   
48.
A method for obtaining high-molecular-weight chromosomal DNA from Bacteroides intermedius and Bacteroides gingivalis is described. This technique is a modification of the guanidine isothiocyanate isolation procedure for RNA and should be useful for isolating intact DNA from organisms with high endogenous nuclease activity.  相似文献   
49.
Spectrophotometric assay for ornithine decarboxylase   总被引:11,自引:0,他引:11  
A rapid and sensitive spectrophotometric assay for ornithine decarboxylase is described. It is based on the observation that the product of ornithine decarboxylase, putrescine, reacts with 2,4,6-trinitrobenzenesulfonic acid to give a colored product soluble in 1-pentanol whereas ornithine does not. The amount of putrescine produced by the enzyme was determined by measuring the absorbance of the 1-pentanol extract of the reaction mixture at 420 nm, and by comparing the results to those obtained by the trapping of 14CO2 and by HPLC assays. The three assays were found to be equivalent in sensitivity, with the spectrophotometric assay having the advantages of being relatively rapid, requiring only common laboratory equipment, and not requiring the use of radioactive isotopes.  相似文献   
50.
Summary The assignment of the human prealbumin (PALB) gene to chromosome region 18q11–q12.1 has been achieved using a human genomic probe in the study of human-mouse somatic cell hybrids and by in situ hybridization. Because familial amyloidotic polyneuropathy was reported previously to be due to a mutation in prealbumin, it can be inferred that the gene for this disorder also maps to 18q11.2–q12.1.  相似文献   
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