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151.
BACKGROUND: Reference drug pricing (RP) is a cost-sharing strategy commonly used to control drug expenditures. Under RP, a benefit plan fully reimburses medications that are equally or less expensive than the reference price, and requires patients to pay the extra cost of therapeutically equivalent but higher priced drugs. Critics argued that drug plan savings are offset by administrative costs and increased spending on other health services. OBJECTIVE: We evaluated net healthcare savings in beneficiaries >or=65 years from the perspective of the British Columbia provincial health insurance system after it applied RP to angiotensin-converting enzyme (ACE) inhibitors in 1997. METHODS: We estimated savings in new users of antihypertensives after the start of RP plus associated administrative costs and savings from reductions in retail drug prices. Findings were integrated with earlier results on the consequences of RP on expenditures for drugs, physicians, and hospitalizations among all seniors who used ACE inhibitors before the introduction of RP. RESULTS: During the first year after the implementation of RP, savings for continuous users were CAN dollars 6.0 million. Savings for new users were dollars 0.2 million. Approximately five sixths thereof were achieved by utilization changes and one sixth by cost shifting to patients. There were no savings through drug price changes. Administering RP cost dollars 0.42 million. Overall net savings were estimated to be dollars 5.8 million during the first year after the start of RP. The magnitude of these savings is equal to 6% of all cardiovascular drug expenditures in seniors. After 10 years, approximately 50% of savings will be achieved by new users. CONCLUSION: We observed substantial net savings from RP for ACE inhibitors for the provincial health insurance system in British Columbia, although there were generous exemptions from the policy. In other jurisdictions, savings could be higher if drug prices decline after the start of reference pricing.  相似文献   
152.
The existence of atypical lymphocytes with specific morphological characteristics in the peripheral blood of schizophrenic patients has been suggested in several reports over the last 40 years. In our study this observation was examined not only by using the formerly applied method of light microscopy for general cell distribution and lymphocyte morphology but also by applying flow cytometry, a well established immunological method for lymphocyte patterns such as lymphocyte subgroups and lymphocyte activity. In contrast to the previously published data, our results demonstrated no differences in cell distribution (lymphocytes, polymorphonuclear cells, eosinophil and basophil granulocytes, monocytes), lymphocyte morphology ("atypical lymphocytes" vs. "normal lymphocytes"), distribution of lymphocyte-subtypes (T-cells (CD3(+)), T-helper-cells (CD3(+)/CD4(+)), cytotoxic T-cells (CD3(+)/CD8(+)), B-cells (CD19(+)), NK-cells (CD3(-)/CD56(+))) or state of T-lymphocyte activity (CD25(+) or HLA-DR(+)-cells) in schizophrenic patients compared to healthy controls. We suggest that possible immunological alterations in schizophrenia do not correlate with morphological characteristics of lymphocytes observable by light microscopy or an altered state activity of T-lymphocytes examined by flow cytometric parameters. Further studies should concentrate on intracellular and functional aspects of the different lymphocyte subgroups.  相似文献   
153.
Abstract The age-related structural changes of the human hippocampus are not entirely understood. The goal of the present investigation was to understand better the nature of age-related hippocampal changes by a comparative MR-analysis of four complementary aspects of hippocampal integrity: total volume, metabolite concentration, neuron to glial cell ratio and amount of extracellular diffusion space for water. To that end, we applied MR-based methods of manual and computerized (voxel-based morphometry) volumetry, diffusion-weighted imaging and 1H MR spectroscopy to characterize specific age-related hippocampal effects in a group of 22 healthy old adults in comparison with a group of 13 healthy younger adults. Age-related reductions of the hippocampal N-acetyl aspartate to creatine/choline ratio together with only marginal age-related reductions in hippocampal volumes and increases in diffusion parameters suggest that the process of aging affects mainly the metabolic status of the hippocampus with little equivalent age-related changes in hippocampal cell density. The metabolic changes are unspecific as they are not restricted to the hippocampus but equally occur in measures obtained from extrahippocampal temporal lobe regions.  相似文献   
154.
Abstract. Neuronal consequences of recurrent single epileptic seizures have been discussed controversially for some time. Various cross-sectional magnetic resonance imaging (MRI) studies have shown a positive correlation between the severity of epilepsy and the extent of hippocampal damage. However, the open question whether recurrent epileptic seizures induce hippocampal structural pathology can be assessed only in longitudinal studies. The few recent follow-up studies have revealed conflicting results. In the current MRI study we have employed volumetry and T2 relaxometry to quantify hippocampal structural changes of patients with chronic partial epilepsies over a period of 3 years. Our main findings demonstrate that these patients who experience continuing epileptic seizures do no show any development of new pathology or any relevant deterioration of pre-existing hippocampal structural lesions. This argues against the assumption that recurrent epileptic seizures cause or increase structural hippocampal damage.  相似文献   
155.
BACKGROUND: In pharmacodynamic studies with antiplatelet agents, platelets are usually activated in vitro with single agonists (e.g., ADP) solely. We questioned whether differences occur between single and combined stimulation of platelets [involving the major thrombin-receptors, protease-activated receptors (PAR)1 and PAR4], and whether the pharmacodynamic response to common antiplatelet drugs vary when a combined stimulus is applied instead of a single agonist. METHODS: We investigated the influence of different antiplatelet agents (aspirin [500 mg]) in vivo, the P2Y12-antagonist AR-C 69931MX (4 nM) and the GPII/IIIa-antagonist (abciximab ([5 microg/ml] in vitro) on the degranulation response (CD62) and expression of the activated GPIIb/IIIa-receptor (PAC-1) after stimulation with ADP (2 microM), collagen (4 microg/ml), a PAR1-activating peptide (3 microM TRAP) and a PAR4-activating peptide (200 microM AYPGKF) alone or in a combination of each two agonists by flow cytometry in healthy subjects. RESULTS: (1) Combined activation of TRAP with AYPGKF resulted in synergistic CD62 and PAC-1 expression. Only AYPGKF but neither TRAP nor ADP acted synergistically with collagen. (2) AR-C 69931MX inhibited platelet degranulation (CD62) in all inducer combinations with ADP or the combination TRAP with AYPGKF. The effect was considerably smaller or absent for the combination of collagen with a second inducer. (3) Aspirin intake reduced platelet degranulation and PAC-1 expression only for AYPGKF costimulation with collagen. CONCLUSION: Because a variety of different agonists influence platelet activation and its distinct functions at a time, investigations which regard the concert of these agonists might be closer to the in vivo situation and better reflect the pharmacodynamic profile of an antiplatelet agent than using one single inducing agent.  相似文献   
156.
Milestones of neuronal development in the adult hippocampus   总被引:26,自引:0,他引:26  
Adult hippocampal neurogenesis originates from precursor cells in the adult dentate gyrus and results in new granule cell neurons. We propose a model of the development that takes place between these two fixed points and identify several developmental milestones. From a presumably bipotent radial-glia-like stem cell (type-1 cell) with astrocytic properties, development progresses over at least two stages of amplifying lineage-determined progenitor cells (type-2 and type-3 cells) to early postmitotic and to mature neurons. The selection process, during which new neurons are recruited into function, and other regulatory influences differentially affect the different stages of development.  相似文献   
157.
BACKGROUND: Anecdotal reports suggest that the second trimester is the safest time to conduct a laparoscopic procedure on a pregnant patient, but this supposition has not been tested empirically. METHODS: Previously instrumented preterm sheep (total n = 8) at gestational day 90 (term, 145 days) were anesthetized and then insufflated with carbon dioxide for 60 min at a pressure of 15 mmHg. Cardiovascular parameters were continuously recorded while blood gas status was determined before and at 15-min intervals during and up to 2 h after insufflation. RESULTS: Insufflation produced minimal maternal blood gas or cardiovascular changes except for a significant reduction in uterine blood flow. The decrease in perfusion increased fetal arterial blood partial pressure of carbon dioxide and decreased fetal pH, oxygen saturation, and oxygen content; there was also progressive fetal hypotension and bradycardia. After manually deflating the ewe, uterine blood flow returned to normal, and the fetal partial pressure of carbon dioxide and pH changes resolved within 1 h. However, fetal oxygen saturation and content remained depressed, and fetal cardiovascular status continued to decline during the 2-h postinsufflation monitoring period. CONCLUSION: Previous studies with near-term sheep determined that carbon dioxide pneumoperitoneum produces respiratory acidosis but does not decrease fetal oxygenation. In contrast, the current findings indicate that in the preterm fetus, insufflation-induced hypercapnia and acidosis are accompanied by prolonged fetal hypoxia and cardiovascular depression. This result suggests that additional work should be conducted to confirm the presumed safety of conducting minimally invasive procedures during the second trimester.  相似文献   
158.
The 5'AMP-activated protein kinase (AMPK) is a potential antidiabetic drug target. Here we show that the pharmacological activation of AMPK by 5-aminoimidazole-1-beta-4-carboxamide ribofuranoside (AICAR) leads to inactivation of glycogen synthase (GS) and phosphorylation of GS at Ser 7 (site 2). In muscle of mice with targeted deletion of the alpha2-AMPK gene, phosphorylation of GS site 2 was decreased under basal conditions and unchanged by AICAR treatment. In contrast, in alpha1-AMPK knockout mice, the response to AICAR was normal. Fuel surplus (glucose loading) decreased AMPK activation by AICAR, but the phosphorylation of the downstream targets acetyl-CoA carboxylase-beta and GS was normal. Fractionation studies suggest that this suppression of AMPK activation was not a direct consequence of AMPK association with membranes or glycogen, because AMPK was phosphorylated to a greater extent in response to AICAR in the membrane/glycogen fraction than in the cytosolic fraction. Thus, the downstream action of AMPK in response to AICAR was unaffected by glucose loading, whereas the action of the kinase upstream of AMPK, as judged by AMPK phosphorylation, was decreased. The fact that alpha2-AMPK is a GS kinase that inactivates GS while simultaneously activating glucose transport suggests that a balanced view on the suitability for AMPK as an antidiabetic drug target should be taken.  相似文献   
159.
OBJECTIVES: This study sought to identify demographic, socioeconomic, and clinical predictors of aftercare noncompliance by pediatric emergency department (ED) patients. METHODS: The authors conducted a prospective, observational study of pediatric patients presenting to a university teaching hospital ED from July 1, 2002, through August 31, 2002. Demographic and clinical information was obtained from guardians during the ED visit. Guardians were contacted after discharge to determine compliance with ED aftercare instructions. Subjects were excluded if they were admitted or if guardians were unavailable or unwilling to consent. Data were analyzed using multivariable logistic regression to identify predictors of noncompliance from a list of predetermined variables. RESULTS: Of the 409 patients enrolled in the study, 111 were prescribed medications and 364 were given specific follow-up instructions. Subtypes of the variable "insurance status" were significantly associated with medication noncompliance in multivariable regression analysis. "Insurance status" and "low-acuity discharge diagnoses" were significantly associated with follow-up noncompliance. CONCLUSIONS: Disparity in health insurance has been shown to be a predictor of poor aftercare compliance for pediatric ED patients within the patient population.  相似文献   
160.
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