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971.
Chiral resolution of a number of cationic drugs of forensic interest (amphetamine, methamphetamine, cathinone, methcathinone, cathine, cocaine, propoxyphene, and various alpha-hydroxyphenethylamines) is achieved via capillary electrophoresis (CE) with added cyclodextrins (CDs), including novel mixtures of neutral and anionic CDs. In the latter studies, resolution and migration speed are readily adjusted by varying the ratio of the two added CDs, as the anionic CD acts as a counter-migrating complexing reagent. The neutral CD, heptakis(2,6-di-O-methyl)-beta-CD, was found suitable for the analysis of illicit cocaine and khat leaves (Catha edulis Forsk), which contain (-)-alpha-aminopropiophenone ((-)-cathinone), (+)-norpseudoephedrine (cathine), (-)-norephedrine, and trace levels of the phenylpentenylamines (+)-merucathinone, (+)-merucathine, and possibly (-)-pseudomerucathine. The use of mixtures of the neutral and the anionic CD (beta-CD sulfobutyl ether IV) was found suitable for the analysis of illicit amphetamine, methamphetamine, methcathinone, and propoxyphene. A model is presented for the impact of mixtures of neutral and anionic CDs on migration behavior and chiral resolution in CE.  相似文献   
972.
An outbreak of 26 cases of vampire bat bite in one month in the rural area of Honorópolis, a Brazilian village, is reported. All patients were bitten during the night, when they were asleep, and most bites were on their toes. No complication attributed to the bite was reported. The patients were given prophylactic antirabies serum and rabies vaccine. Control of the outbreak was achieved by visiting bat roosting sites, smearing captured vampire bats (Desmodus rotundus) with a paste of 2% warfarin in vaseline, and releasing them. No case of human or animal rabies was diagnosed in a 5-month follow-up. A possible explanation for the outbreak of bat bite is that, because of man-induced environmental modifications in their habitats, vampire bats in Honorópolis now live in the peridomiciliar area, where people are more exposed to their bites. An alternative explanation is related to the use in cattle of a pyrethroid insecticide to control the horn fly, Haematobia irritans, as both events were temporally related. The insecticide could have had a repellent effect on bats, that then started to seek alternative food sources.  相似文献   
973.
Successful eradication of Helicobacter pylori infection in children has required long treatment regimens that may result in noncompliance with failure to eradicate this organism. Despite full compliance with shorter therapeutic regimens, such as amoxycillin and omeprazole for 2 wk, the H. pylori eradication rate is poor in children. OBJECTIVES: The aim of this study was to evaluate the efficacy of, and compliance with, a 2-wk treatment with metronidazole, omeprazole, and clarithromycin in eradicating H. pylori disease in children. METHODS: Over a 15-month period, children diagnosed to be H. pylori positive by Steiner's stain of gastric antral biopsy specimens were treated with metronidazole, omeprazole, and clarithromycin. Follow-up upper GI endoscopy was performed 6-8 wk after completion of therapy. RESULTS: Of 15 patients with H. pylori-positive antral gastritis, 11 had duodenal ulcer disease; three patients with severe abdominal pain and one with vomiting had H. pylori gastritis only. H. pylori eradication was seen in 11 of 11 (100%) patients with duodenal ulcer disease and in three of four (75%) with gastritis only; the overall success rate was 93%. Duodenal ulcer disease healed when H. pylori was eradicated in all but one patient, who at presentation had a penetrating ulcer with a duodenobiliary fistula. Fourteen of 15 patients (93%) were fully compliant, and no adverse reactions were reported. CONCLUSIONS: Two weeks of therapy with metronidazole, omeprazole, and clarithromycin is effective H. pylori therapy in children. It is well tolerated, and full compliance can be achieved.  相似文献   
974.
Two-year postsurgical developmental outcomes were assessed in 24 children with infantile spasms who underwent resective surgery. The mean age of onset of infantile spasms was 12.0 weeks and the mean age at surgery was 20.8 months. Developmental outcomes were assessed using the Vineland Adaptive Behavior Scales (VABS). There was a significant increase in developmental level at 2 years postsurgery compared with presurgical levels. At 2 years postsurgery only one of the children in this series was severely retarded. The developmental outcomes of patients in the series were better than those in prior studies of symptomatic patients receiving medical treatment for infantile spasms. It is surprising that the children in the UCLA series frequently had developmental outcomes equal to and sometimes superior to other groups of children with infantile spasms, since all the UCLA patients were symptomatic, had neurologic deficits and had failed to respond to adrenocorticotrophic hormone (ACTH) and antiepileptic drugs. The 2-year postsurgery developmental outcomes were best for the children who received surgery when they were relatively young and who had the highest level of developmental attainments presurgically.  相似文献   
975.
OBJECTIVE: To ascertain whether childbearing would decrease oral glucose-stimulated insulin and C-peptide levels and increase the risk of NIDDM and impaired glucose tolerance in a population of Hispanic and non-Hispanic white women residing in the San Luis Valley of Colorado. Several investigators have related childbearing to subsequent abnormal glucose tolerance. RESEARCH DESIGN AND METHODS: In a population-based case-control epidemiological study, diabetic patients 20-74 yr of age (n = 196) and randomly sampled control women subjects (n = 735) underwent a glucose tolerance test, a physical examination, and an in-person standardized interview. The relations between the live-birth number and fasting and oral glucose stimulated glucose, insulin and C-peptide concentrations, and NIDDM and impaired glucose tolerance were estimated using linear or logistic regression to adjust for extraneous variables. RESULTS: In women selected as control subjects, the live-birth number was related to a significant decrease in the sum of 1- and 2-h C-peptide concentrations (coefficient = -0.077, P < 0.001) and the logarithm of the sum of 1- and 2-h insulin concentrations (coefficient = -0.014, P = 0.02). After adjustment for subscapular skin-fold thickness, the relative odds of NIDDM for the live-birth number, which was small and of borderline significance, diminished (odds ratio = 1.04 for one birth, P = 0.18). Findings were similar for impaired glucose tolerance. CONCLUSIONS: Childbearing was related to lower C-peptide and insulin levels in Hispanic and non-Hispanic women of the San Luis Valley. It had little apparent effect on later risk of NIDDM or impaired glucose tolerance.  相似文献   
976.
Delusions of parasitosis is a rare disorder in which patients have the false and fixed belief that they are infested by parasites. It is a psychiatric disorder, but patients usually present to a dermatologist and referral to a psychiatrist is almost always rejected. Treating a patient with delusions of parasitosis requires patience and tact. The neuroleptic pimozide is the treatment of choice, but a significant problem is convincing the patient to take the drug. We report a study of 33 patients (13 men and 20 women) with delusions of parasitosis. The mean age at onset was 56.9 years and the mean duration of symptoms before attending the department of dermatology was 1.3 years. Pimozide (Orap) was prescribed for 24 patients, but only 18 patients took it. Follow-up information was available for 18 patients: five had full remission, four were less symptomatic, five were unchanged and four had died of unrelated causes.  相似文献   
977.
Underhand pitching has received minimal attention in the sports medicine literature. This may be due to the perception that, compared with overhead pitching, the underhand motion creates less stress on the arm, which results in fewer injuries. The purpose of this study was to calculate kinematic and kinetic parameters for the pitching motion used in fast pitch softball. Eight female fast pitch softball pitchers were recorded with a four-camera system (200 Hz). The results indicated that high forces and torques were experienced at the shoulder and elbow during the delivery phase. Peak compressive forces at the elbow and shoulder equal to 70-98% of body weight were produced. Shoulder extension and abduction torques equal to 9-10% of body weight x height were calculated. Elbow flexion torque was exerted to control elbow extension and initiate elbow flexion. The demand on the biceps labrum complex to simultaneously resist glenohumeral distraction and produce elbow flexion makes this structure susceptible to overuse injury.  相似文献   
978.
The purpose of our study was to compare selective arterially enhanced spiral computed tomographs (ACT) with digital subtraction angiographies (DSA) in the presurgical assessment of cerebral aneurysms. A total of 24 aneurysms in 18 patients were explored in a prospective study by ACT and DSA, using an interactive combined CT-angiography suite. Dimensions of the aneurysm, its relation to the parent vessel, and the aneurysmal index were defined on DSA and on surface-shaded display of 3D reformatted images obtained from ACT. Results were correlated with surgical findings. Three aneurysms suspected on DSA were not confirmed by ACT. One fusiform aneurysm suspected on DSA corresponded to a sacciform aneurysm on ACT. Surgical findings confirmed 20 sacciform aneurysms. The aneurysmal index could be measured in all 20 cases of sacciform aneurysms on ACT and could not be determined with confidence in 55 % of the cases on DSA. DSA and ACT gave identical results in 35 % of cases. In 10 %, the index measured by ACT was superior to that determined by DSA for aneurysms which had a diameter of less than 3 mm. In conclusion, the combination of DSA and ACT improved the results of DSA alone. ACT is a reliable method to measure the aneurysmal index in aneurysms with a diameter superior to 3 mm.  相似文献   
979.
The regulation of central mu-opioid receptors in women during the menstrual cycle was explored with positron emission tomography and the selective radiotracer [11C]carfentanil. Ten healthy women were studied twice, during their follicular and luteal phases. Plasma concentrations of estradiol, progesterone, testosterone, and beta-endorphin were determined immediately before scanning. LH pulsatility was measured over the 9 h preceding each of the two positron emission tomography scans. No significant differences in the binding potential of mu-opioid receptors (binding capacity/Kd) were observed between phases of the menstrual cycle. However, significant negative correlations were observed between circulating levels of estradiol during the follicular phase and mu-receptor binding measures in the amygdala and hypothalamus, two regions thought to be involved in the regulation of GnRH pulsatility. LH pulse amplitude was positively correlated with mu binding in the amygdala, whereas LH pulse number was negatively correlated with binding in this same region. No significant associations were noted between LH pulse measures and the hypothalamus for this sample. These results suggest that amygdalar mu-opioid receptors exert a modulatory effect on GnRH pulsatility, and that circulating levels of estradiol also regulate central mu-opioid function.  相似文献   
980.
Mammalian adenylyl cyclases possess 12 transmembrane-spanning domains and bear a superficial resemblance to certain classes of ion channels. Some evidence suggests that bacterial and sea urchin sperm adenylyl cyclases can be regulated by membrane depolarization. In the present study, we explored the effect of altering membrane potential on the adenylyl cyclase activity of cerebellar granule cells with acute potassium depolarization. A biphasic stimulatory and then inhibitory response is evoked by progressive increases in the extracellular [K]:[Na] ratio in the absence of extracellular Ca2+. This effect does not mimic the linear increase in membrane potential elicited under the same conditions. Instead it appears as though membrane depolarization opens L-type (nimodipine-sensitive) Ca2+ channels, allowing the entry of Na+, which directly stimulates adenylyl cyclase activity. Gramicidin, which generates pores that are permeable to monovalent cations, and concurrently eliminates the membrane potential, permits a similar stimulation by extracellularly applied Na+. Although the results indicate no direct sensitivity of cerebellar granule cell adenylyl cyclase to membrane potential, they do demonstrate that, as a result of membrane depolarization, the influx of Na+, as well as Ca2+, will elevate cAMP levels.  相似文献   
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