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Objective: To determine serotonin system abnormalities related to major depression or previous suicidal behavior.

Methods: [11C]WAY100635, [18F]altanserin and positron emission tomography were used to compare 5-HT1A and 5-HT2A binding in MDD patients divided into eight past suicide attempters (>4yrs prior to scanning) and eight lifetime non-attempters, and both groups were compared to eight healthy volunteers.

Results: The two receptor types differed in binding pattern across brain regions from each other, but there were no differences in binding between healthy volunteers and the two depressed groups or between depressed suicide attempters and non-attempters. No effects of depression severity or lifetime aggression were observed for either receptor.

Conclusion: Limitations of this study include small sample size and absence of high lethality suicide attempts in the depressed attempter group. No trait-like binding correlations with past suicide attempt or current depression were observed. Given the heterogeneity of nonfatal suicidal behavior, a larger sample study emphasizing higher lethality suicide attempts may find the serotonin biological phenotype seen in suicide decedents.  相似文献   

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OBJECTIVES: Resin-modified glass ionomer cements (RMGI) are hybrid materials prepared by incorporation of polymerizable components (typically 2-hydroxyethyl methacrylate (HEMA) with possible addition of multifunctional methacrylates) into a conventional acid-base mixture (a polymeric acid with powdered calcium fluoro-aluminosilicate glasses). During setting, the photopolymerization process and the acid-base reaction affect each other. The aim of this work was to examine the effect of a 45% aqueous solution of poly(acrylic acid) (PAA) and the liquid component of a commercial glass ionomer cement on HEMA and triethyleneglycol dimethacrylate (TEGDMA) photopolymerization. METHODS: The polymerization was initiated by 2,2-dimethoxy-2-phenylacetophenone (DMPA) and camphorquinone (CQ)/coinitiator system. The reaction course was monitored under Ar and air by isothermal differential scanning calorimetry. RESULTS: The main effect of addition of polyacid solution (PAA and commercial) up to 10wt% to HEMA on the polymerization initiated with DMPA was earlier onset of autoacceleration. For the process initiated by the CQ-based system, the addition of 5wt% of PAA solution strongly accelerated the polymerization and increased the conversion, both in Ar atmosphere as well as in air. TEGDMA photopolymerization was not influenced or slightly retarded by the presence of 3wt% of PAA solution (the upper limit of solubility), depending on the initiating system used. SIGNIFICANCE: Under initiation conditions used in curing of commercial dental products (CQ-based two component initiating system), the presence of polyacid-aqueous solution in HEMA-based photocurable component increases markedly the polymerization rate and the conversion both in Ar atmosphere as well as in air. This result contributes to a characterization of the setting process of RMGIs.  相似文献   
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Lowering of the elevated plasma FFA concentration in 18- 24-h fasted rats with nicotinic acid (NA) caused complete ablation of subsequent glucose-stimulated insulin secretion (GSIS). Although the effect of NA was reversed when the fasting level of total FFA was maintained by coinfusion of soybean oil or lard oil (plus heparin), the more saturated animal fat proved to be far more potent in enhancing GSIS. We therefore examined the influence of individual fatty acids on insulin secretion in the perfused rat pancreas. When present in the perfusion fluid at 0.5 mM (in the context of 1% albumin), the fold stimulation of insulin release from the fasted pancreas in response to 12.5 mM glucose was as follows: octanoate (C8:0), 3.4; linoleate (C18:2 cis/cis), 5.3; oleate (C18:1 cis), 9.4; palmitate (C16:0), 16. 2; and stearate (C18:0), 21.0. The equivalent value for palmitoleate (C16:1 cis) was 3.1. A cis--> trans switch of the double bond in the C16:1 and C18:1 fatty acids had only a modest, if any, impact on their potency. A similar profile emerged with regard to basal insulin secretion (3 mM glucose). When a subset of these fatty acids was tested in pancreases from fed animals, the same rank order of effectiveness at both basal and stimulatory levels of glucose was seen. The findings reaffirm the essentiality of an elevated plasma FFA concentration for GSIS in the fasted rat. They also show, however, that the insulinotropic effect of individual fatty acids spans a remarkably broad range, increasing and decreasing dramatically with chain length and degree of unsaturation, respectively. Thus, for any given level of glucose, insulin secretion will be influenced greatly not only by the combined concentration of all circulating (unbound) FFA, but also by the makeup of this FFA pool. Both factors will likely be important considerations in understanding the complex interplay between the nature of dietary fat and whole body insulin, glucose, and lipid dynamics.  相似文献   
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Effects of bar coding on a pharmacy stock replenishment system   总被引:2,自引:0,他引:2  
A bar-code stock ordering system installed in the ambulatory-care pharmacy and sterile products area of a hospital pharmacy was compared with a manual paper system to quantify overall time demands and determine the error rate associated with each system. The bar-code system was implemented in the ambulatory-care pharmacy in November 1987 and in the sterile products area in January 1988. It consists of a Trakker 9440 transaction manager with a digital scanner; labels are printed with a dot matrix printer. Electronic scanning of bar-code labels and entry of the amount required using the key-pad on the transaction manager replaced use of a preprinted form for ordering items. With the bar-code system, ordering information is transferred electronically via cable to the pharmacy inventory computer; with the manual system, this information was input by a stockroom technician. To compare the systems, the work of technicians in the ambulatory-care pharmacy and sterile products area was evaluated before and after implementation of the bar-code system. The time requirements for information gathering and data transfer were recorded by direct observation; the prevalence of errors under each system was determined by comparing unprocessed ordering information with the corresponding computer-generated "pick lists" (itemized lists including the amount of each product ordered). Time consumed in extra trips to the stockroom to replace out-of-stock items was self-reported. Significantly less time was required to order stock and transfer data to the pharmacy inventory computer with the bar-code system than with the manual system.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
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ABSTRACT: Pemphigus vulgaris (PV) is an autoimmune disease of the skin and mucous membranes characterized by an autoantibody response against an epidermal cadherin. We performed high resolution HLA class II typing in 19 patients with PV from Rawalpindi, Pakistan and 19 non-Jewish European PV patients from Boston by sequence-specific oligonucleotide probe hybridization. The results were compared with two separate ethnically matched control populations. We found that PV patients from Pakistan had significantly increased frequencies of DRB1*1404 ( p = 0.01), DQA1*0101 ( p = 0.02), and DQB1*0503 ( p = 0.01). Among the patients of non-Jewish European ancestry, DRB1*1401 ( p < 10−6), DQA1*0101 ( p < 10−5) and DQB1*0503 ( p < 10−6), were increased in PV patients. Formal linkage analysis between the major histocompatibility complex and the PV antibody was performed in 67 relatives of the 19 Pakistani patients. The results showed strong evidence for linkage of HLA-DRB1*1404, DQA1*0101, DQB1*0503, with the presence of PV antibody in relatives’ families with a significant logarithm of the odds score of 6.06. Based on the three dimensional structure of class II molecules, we propose that HLA-DQA1*0101 and DQB1*0503, encode a negatively charged P9 peptide binding pocket of the DQ molecule and are significantly associated with susceptibility to PV in non-Jewish populations.  相似文献   
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