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51.
BACKGROUND: A systematic approach to determining drug intoxication has been developed for use by police officers. By considering specific physiological signs, trained officers can detect the effects of seven major drug types. METHODS: Officers follow a 12-step testing sequence and evaluate signs such as pupil sizes and responses, eye movements, heart rate, body temperature, mental timing, and balance. A matrix is then used to compare that subject's signs to those that would be produced by the seven types of drugs. If a pattern match is found, the officer concludes that the subject is under the influence of a drug and specifies the drug type. RESULTS: Several field and laboratory validation studies have been conducted using these procedures. In general, officers were 70% to 90% accurate in determining intoxication status and drug classification, but poly-drug use and drug rebound effects can sometimes cause problems in interpretation. CONCLUSION: Ocular and other physiological signs can be used to detect drug intoxication and classify the type of drug taken. Knowledge of the procedures used in the Drug Recognition Program can enable optometrists to serve as consultants to the police and as expert witnesses in cases involving the use of ocular signs that indicate illicit drug use.  相似文献   
52.
The purpose of this double-blind study was to investigate the influence of adding a quercetin-containing supplement to the diet on plasma quercetin status, serum/platelet fatty acid levels and risk factors for heart disease. Healthy men and women with cholesterol levels of 4.0-7.2 mmol/L, consumed four capsules daily of either a quercetin-containing supplement (1.0 g quercetin/d) or rice flour placebo for 28 d. Quercetin intakes were approximately 50-fold greater than the dietary intakes associated with lower coronary heart disease mortality on the basis of epidemiologic studies. Subjects consuming quercetin-containing capsules had plasma quercetin concentrations approximately 23-fold higher than those of subjects consuming the control capsules. Quercetin supplementation did not modify serum total, LDL or HDL cholesterol or triglyceride levels. There were also no alterations of other cardiovascular disease or thrombogenic risk factors, including platelet aggregation, platelet thromboxane B2 production, blood pressure or resting heart rate. Furthermore, there was no effect on the levels of (n-6) or (n-3) polyunsaturated fatty acids in serum or platelet phospholipids. In conclusion, supplementation with quercetin-containing capsules markedly enhanced the plasma quercetin concentration but had no effect on other cardiovascular or thrombogenic risk factors.  相似文献   
53.
Adherence with inhaled beta-agonists and corticosteroids in 24 asthmatic children was tracked over 3 months utilizing the metered-dose inhaler chronolog (MDIC). Patients seldom took all of their medications as prescribed, and failed to take any inhaled corticosteroid doses on a median of 41.8% of days or inhaled beta-agonists on 28.1% of days despite prescribed daily use. Medication nonadherence was correlated with lower levels of asthma knowledge (Asthma Knowledge Questionnaire) and family dysfunction (Family Assessment Device), but not child behavior disorder (Child Behavior Checklist). Patients tended to dramatically over-report medication use. Improved identification of the markers of nonadherence can directly facilitate more efficient targeting of behavioral interventions, resulting in improved adherence, better illness control, and less requirement of urgent medication intervention.  相似文献   
54.
Studies conducted with the goal of discovering a second-generation platelet-activating factor (PAF) antagonist have identified a novel class of potent and orally active antagonists which have high aqueous solubility and long duration of action in animal models. The compounds arose from the combination of the lipophilic indole portion of Abbott's first-generation PAF antagonist ABT-299 (2) with the methylimidazopyridine heterocycle moiety of British Biotechnology's BB-882 (1) and possess the positive attributes of both of these clinical candidates. Structure-activity relationship (SAR) studies indicated that modification of the indole and benzoyl spacer of lead compound 7b gave analogues that were more potent, longer-lived, and bioavailable and resulted in the identification of 1-(N, N-dimethylcarbamoyl)-4-ethynyl-3-[3-fluoro-4-[(1H-2-methylimidazo[4,5-c] pyrid-1-yl)methyl]benzoyl]indole hydrochloride (ABT-491, 22 m.HCl) which has been evaluated extensively and is currently in clinical development.  相似文献   
55.
BACKGROUND: Withdrawal from long-term cocaine use is accompanied by symptoms resembling major depression. Because acute cocaine affects serotonin (5-HT) neurons, and 5-HT dysfunction is implicated in the pathophysiology of depression, we evaluated the effects to 5-HT agonists in rats withdrawn from repeated injections of cocaine (15 mg/kg i.p., b.i.d., 7 days) or saline. METHODS: In the first study, prolactin (PRL) responses elicited by the 5-HT-releasing agent fenfluramine, the 5-HT1A agonist (+/-)-8-hydroxy-2-(di-n-propylamino)tetralin (8-OH-DPAT), and the 5-HT2A/2C agonist (+/-)-1-(2,5-dimethoxy-4-iodophenyl)-2-aminopropane hydrochloride (DOI) were examined as indices of postsynaptic 5-HT receptor function. In a second study, specific responses induced by 8-OH-DPAT, namely inhibition of brain 5-HT synthesis and stimulation of feeding, were examined as correlates of 5-HT1A autoreceptor function. RESULTS: Prior treatment with cocaine did not modify fenfluramine-evoked PRL release; however, the PRL secretory response to 8-OH-DPAT was blunted and the PRL response to DOI was potentiated after chronic cocaine treatment. Cocaine exposure did not alter the inhibitory effect of 8-OH-DPAT on 5-HT synthesis. 8-OH-DPAT-induced feeding was influenced by prior cocaine, but this effect was secondary to pronounced baseline hyperphagia in the cocaine-treated group. CONCLUSIONS: These data indicate that withdrawal from chronic cocaine renders specific subpopulations of postsynaptic 5-HT1A receptors subsensitive and 5-HT2A/2C receptors supersensitive. No evidence for cocaine-induced changes in 5-HT1A autoreceptor responsiveness was found. A survey of the literature reveals similarities in the profile of 5-HT dysfunction between rats withdrawn from cocaine and humans diagnosed with depression. We propose that withdrawal from chronic cocaine in rats may serve as a useful animal model of depressive disorders.  相似文献   
56.
BACKGROUND: Prior research has suggested reductions in the density of serotonin transporter (SERT) binding sites in blood platelets and post-mortem brain tissue of depressed patients. We sought to determine whether patients with unipolar major depression have diminished SERT availability as assessed by both brainstem [123I] beta-CIT SPECT and platelet [3H]paroxetine binding. METHODS: Drug-free depressed and healthy subjects were injected with 211 +/- 22 MBq [123I] beta-CIT and imaged 24 +/- 2 h later under equilibrium conditions. A ratio of specific to nonspecific brain uptake (V3" = (brainstem-occipital)/occipital), a measure proportional to the binding potential (Bmax/Kd), was used for all comparisons. RESULTS: Results showed a statistically significant reduction in brainstem V3" values in depressed as compared to healthy subjects (3.1 +/- .9 vs. 3.8 +/- .8, p = .02). Platelet [3H]paroxetine binding was not altered (Bmax = 2389 +/- 484 vs. 2415 +/- 538 fmol/mg protein, p = .91) and was not significantly correlated with brainstem [123I] beta-CIT binding (r = -0.14, p = .48). CONCLUSIONS: These data are the first to suggest reductions in the density of brain SERT binding sites in living depressed patients. These findings provide further support for a preeminent role for alterations in serotonergic neurons in the pathophysiology of depression.  相似文献   
57.
Hereditary nonpolyposis colorectal cancer (HNPCC) is a syndrome involving a predisposition to cancers of the colon, endometrium and several other extra-colonic sites, accounting for approximately 1-5% of all colorectal cancer cases. It is not easily recognized because of a lack of distinctive clinical markers, making diagnosis and management of this disease problematic. To provide a basis for uniformity in diagnosis of HNPCC, the Amsterdam criteria were proposed and are currently in use. More recently, the discovery of four human mismatch repair genes (hMSH2, hMLH1, hPMS1 and hPMS2) has provided novel insight into the genetic basis of this disease, and raised the possibility of genetic diagnosis for management of HNPCC patients and their family members. This report summarizes the clinicopathologic aspects of HNPCC, reviews the recent genetic findings and surveillance strategies, and suggests a novel designation of certain patients as suspected HNPCC.  相似文献   
58.
In Hirschsprung's disease (HD), certain intestinal nervous plexuses are absent. Sprouting nerve endings contain different amounts of synaptophysin (SY), a protein and main constituent of acetylcholinesterase (AChE) storage compartments. Due to the lack of specific markers for synapses, a qualitative analysis of nerve endings of intestinal segments affected by HD has not yet been undertaken. For this study, resected colorectal specimens from patients with HD (n = 8, mean age 2.1 years) were investigated in parallel for AChE, SY, and content of small synaptic vesicles by biochemical, immunohistochemical, and electronmicroscopic means. In the microdissected muscular layer, reduced SY (1.4 microgram/mg total protein, normal 24 +/- 0.3) was observed. Immunohistochemistry showed in affected tissues reduced numbers of SY-positive nerve fibers and nerve endings, which in turn were thickened and distorted, in both the muscle proper and the muscularis mucosae. Combining both morphologic and biochemical findings, in HD the number of cholinergic vesicles in the remaining nerve endings seems to be increased as measured by SY, a marker molecule specific for synaptic vesicles. Our data also suggest that nerve endings in HD may contain high concentrations of cholinergic vesicles, paralleling the known high amounts of acetylcholine and AChE found in intestinal segments of patients with HD.  相似文献   
59.
1. The present study examines the effect of leptin on glucose transport and metabolism in incubated soleus muscle from male lean albino rats. 2. Insulin (100 microU/ml) increased glucose uptake by twofold while the leptin group (100 nmol/l) reached 75% of the insulin response after 1 hr of incubation. However, leptin did not potentiate the insulin effect on glucose uptake in soleus muscle. 3. Leptin elicited a significant increase (27.7%) in total lactate production, accompanied by a three-fold increment in glycogen synthesis from [U-14C]D-glucose. 4. Insulin raised glycogen synthesis by sixfold. The leptin plus insulin group increased glycogen synthesis by eightfold, which is equivalent to the sum of the separated leptin and insulin groups. 5. Leptin per se exerts an insulin-like effect stimulating glucose uptake, glycogen synthesis, and lactate formation and also seems to potentiate the effect of insulin on glucose incorporation into glycogen in incubated soleus muscle.  相似文献   
60.
This study evaluated the efficacy of low-dose dopamine for prevention of amphotericin B-induced nephrotoxicity in autologous bone marrow transplant and leukemia patients. Seventy-one patients undergoing cytoreductive therapy who required amphotericin B were randomly assigned in an unblinded fashion to a group receiving continuous-infusion low-dose dopamine (3 microgram/kg/min) or a group receiving no dopamine. Amphotericin B was dosed at 0.5 or 1.0 mg/kg/day based on computerized tomography scan results or presence of positive blood cultures. No patient received saline boluses. The rate of nephrotoxicity, severity as graded by Southwest Oncology Group toxicity criteria, and time to each grade of nephrotoxicity were compared between the two groups. Eighty percent of the no-dopamine group and 66.7% of the dopamine group developed nephrotoxicity, defined as a 1.5-fold or greater increase in baseline serum creatinine level (P = 0.20). No statistical difference was noted at any grade of nephrotoxicity between the two groups. Thirty-four percent of patients in the no-dopamine group versus 17.6% in the dopamine group had a 2.5-fold or greater increase in serum creatinine level, which was not statistically significant (P = 0.0888). Ten patients developed grade IV nephrotoxicity and were withdrawn from the study, 7 in the no-dopamine group and 3 in the dopamine group (P = 0.19). The time to each grade of nephrotoxicity was also not significantly different for the two groups. Eleven adverse drug reactions were reported in the dopamine group in comparison to one in the no-dopamine group. Thus, dopamine offers little in the way of prevention of nephrotoxicity associated with amphotericin B therapy. Although the significance of drug reactions in the dopamine group is not clearly established due to lack of cardiac monitoring in the no-dopamine group, dopamine therapy is not without complications.  相似文献   
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