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31.
To assess the interaction of dopamine and acetylcholine systems in the rat nucleus accumbens in response to direct D-amphetamine administration, in vivo microdialysis measures of acetylcholine were used during reverse dialysis of amphetamine alone and in combination with D1 and D2 receptor antagonists SCH 23390 and sulpiride, respectively. During a 15-min exposure to amphetamine (50 microM) in the nucleus accumbens, acetylcholine increased to 33% above pre-infusion levels, became maximal at 15 min post-infusion (+41%) and gradually returned to baseline levels by 60 min post-amphetamine. Conversely, amphetamine (1 mM) administration caused a biphasic change in acetylcholine release with a trend toward a decrease (-14%) during exposure followed by a significant increase (+36%) at 30 min post-amphetamine that returned to baseline levels by 60 min after infusion. The increases observed during amphetamine (50 microM) exposure and during recovery from amphetamine (1 mM) were both blocked by co-administration with the D1 antagonist, SCH 23390 (10 microM), but not with the D2 antagonist, sulpiride (10 microM). Co-infusion of sulpiride eliminated the trend toward reduced acetylcholine release observed during 1 mM amphetamine whereas co-administration of SCH 23390 potentiated this decrease. A possible tonic D1 facilitation of nucleus accumbens acetylcholine release was indicated by the consistent reductions in acetylcholine release observed during infusion of SCH 23390. These results suggest that amphetamine administration in the nucleus accumbens induces a bidirectional change in acetylcholine release that is dependent on dose and opposing effects of nucleus accumbens D1 and D2 activation. In general, relatively low doses of amphetamine administered into the nucleus accumbens caused an increase in acetylcholine release that was dependent on dopamine D1 receptors whereas higher doses of amphetamine resulted in a D2-mediated decrease.  相似文献   
32.
We report a 10-year-old boy who presented with a piece of chicken stuck in his throat. He had similar episodes in the past that resolved spontaneously. The foreign body was removed and oesophagoscopy revealed no abnormality. Post-operative barium swallow showed oesophageal intramural pseudodiverticulosis.  相似文献   
33.
The functional status of the oxidative-antioxidative system was studied in 72 patients after vast cancer operations. Traditional surgical treatment and its combination with intraoperative irradiation were shown to lead to tense antioxidative defense and to suppressed T-cell immunity and to call for antioxidative and immunomodulating therapy. High intraoperative blood loss complicated by hemorrhagic shock injured the oxidative-antioxidative system greatly. The magnitude of this damage correlated with the rate of prehypoxia. Addition of the potent antioxidant Ceruloplasmin to the drug regimen normalized a recovery period, helped to correct posthypoxic multiorgan insufficiency, to recover oxidative-antioxidative balance, and to decrease the incidence of pyoinflammatory complications. Patients with endogenous intoxication showed activated lipid peroxidation, decreased functional activity of antioxidative defense components and of T-cell immunity in homeostasis. The use of Ceruloplasmin and Laprot had pronounced antiinflammatory and detoxifying effects on the patient's body and activated its antioxidative defense.  相似文献   
34.
ABSTRACT

A non-hazardous groundwater treatment waste (GWTW) was examined as a low-cost sorbent for Pb(II) and Cu(II) ions. The content of the dominant elements in GWTW was as follows: 78% Fe2O3, 7.4% P2O5, 7.4% CaO and 5.2% SiO2. The removal of Pb(II) and Cu(II) was fast, and more than 67–95% of ions were accumulated by GWTW during the first 3 min. The sorption capacity of GWTW depends on solution pH, concentration and temperature. Equilibrium data fitted well with Langmuir–Freundlich and Langmuir-partition models. The inherently formed nano-adsorbent could be utilized for the treatment of water contaminated with Pb(II) and Cu(II) ions.  相似文献   
35.

Purpose

To examine the effect of betaine supplementation on cycling sprint performance.

Methods

Sixteen recreationally active subjects (7 females and 9 males) completed three sprint tests, each consisting of four 12 sec efforts against a resistance equal to 5.5% of body weight; efforts were separated by 2.5 min of cycling at zero resistance. Test one established baseline; test two and three were preceded by seven days of daily consumption of 591 ml of a carbohydrate-electrolyte beverage as a placebo or a carbohydrate-electrolyte beverage containing 0.42% betaine (approximately 2.5 grams of betaine a day); half the beverage was consumed in the morning and the other half in the afternoon. We used a double blind random order cross-over design; there was a 3 wk washout between trials two and three. Average and maximum peak and mean power were analyzed with one-way repeated measures ANOVA and, where indicated, a Student Newman-Keuls.

Results

Compared to baseline, betaine ingestion increased average peak power (6.4%; p < 0.001), maximum peak power (5.7%; p < 0.001), average mean power (5.4%; p = 0.004), and maximum mean power (4.4%; p = 0.004) for all subjects combined. Compared to placebo, betaine ingestion significantly increased average peak power (3.4%; p = 0.026), maximum peak power max (3.8%; p = 0.007), average mean power (3.3%; p = 0.034), and maximum mean power (3.5%; p = 0.011) for all subjects combined. There were no differences between the placebo and baseline trials.

Conclusions

One week of betaine ingestion improved cycling sprint power in recreationally active males and females.  相似文献   
36.
The purpose of this report was to develop solvent‐free biodegradable drug‐eluting implants that provide sustained release of metronidazole and doxycycline. The drug‐eluting implants were prepared using the compression molding technique. To fabricate the implants, polylactide‐polyglycolide copolymers were premixed with metronidazole or doxycycline. The mixture was then compression molded and sintered to form implants of various sizes and geometries. An elution method and an HPLC assay were used to characterize the in vitro release rates of the antibiotics over a 28‐day period. A bacterial inhibition test was also carried out to determine the bioactivity of released antibiotics. The concentrations of both metronidazole and doxycycline were much greater than the minimum inhibitory concentration of Escherichia coli for up to 3 and 4 weeks, respectively, and the bioactivities of the antibiotics remained high after the fabrication process. Furthermore, the initial burst could be minimized and the release rate could be reduced by increasing the size of the implants and by adopting low drug to polymer ratios. By using this compression molding technique and appropriate processing parameters, we will be able to fabricate biodegradable implants of various types of antibacterial drugs for long‐term local deliveries. Eventually, biodegradable drug‐eluting implants may be used to treat various periodontal diseases. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013  相似文献   
37.
The dynamic curing behavior of sheet molding compound (SMC) has been investigated by using a cylindrical cure reactor. Both thermal and mechanical responses were determined for R-25 SMC paste. The responses from this material were analyzed to determine the chemical and physical transformations that occur during the SMC molding process. The thermal response was obtained from a thermocouple placed along the centerline of the paste sample in the cure reactor. The thermal history at this location shows distinctive stages associated with heat transfer and crosslinking reactions during the cure cycle. The R-25 paste has a precure time of 160 seconds, a reaction time of 25 seconds, and a temperature rise of 134°C. The mechanical response describes the volume change and the pressure of the paste. The displacement curve shows volume changes due to thermal expansion, cure shrinkage, and thermal contraction during the course of a cure cycle. We found a less than 1% shrinkage during the reaction of the R-25 paste. The pressure response of the paste was found to parallel the volume transformation, although it also is strongly influenced by mechanical interactions between the press and the paste.  相似文献   
38.
A series of 238 hydronephrotic kidneys in 219 children is reported. The condition was more common in the male than in the female subject and occurred more frequently on the left side. It was often bilateral, especially in infants, with an abdominal mass as the common presenting feature. Loin or abdominal pain was the most frequent complaint in older children. In some cases hydronephrosis presented as a ruptured kidney following trauma. Only 1 patient was hypertensive. The lesion was asymptomatic in 18 cases and the incidence of urinary infection was low. Dismembered pyeloureteroplasty was the procedure of choice for reconstruction. Preliminary nephrostomy was used rarely and nephrectomy was done in 10 per cent of the kidneys. Of the 7 reoperations 4 were for persistent obstruction and 3 were because stones had formed after the pyeloplasty. The late results, assessed clinically and radiologically, have been entirely satisfactory. Many kidneys of initially doubtful value showed useful improvement after reconstructive operation and no secondary nephrectomies were performed. The only death in the series occurred 2 1/2 years postoperatively and was unrelated to the urinary tract.  相似文献   
39.
Two hundred and thirty-five entrants into the MRC trial for mild to moderate hypertension were matched with control subjects in order to assess the psychological effects of a screening programme and recruitment into a clinical trial. The prevalence and incidence of psychiatric morbidity among the trial participants were compared with those of the controls by means of responses to a self-administered questionnaire and diagnostic psychiatric interviews. No differences among the groups were shown between screening and entry into the trial, but after entry the prevalence of psychiatric morbidity among the trial participants fell. This was due to a greater improvement of those with psychiatric symptoms at entry in this group, the incidence of new morbidity being similar among the groups.  相似文献   
40.
Red cell and haemoglobin values in 44 women with a typical picutre of anorexia nervosa showed that 20.5% presented a picture of true anaemia. Blood iron was low, sometimes very low, with a mean value of 66 mg 0/0. Clotting parameters: PTT, TT, PT, circulating platelets and TEG were normal. This finding serves to explain the low incidence of haemorrhage and the ready haemostasis noted in this disease, in spite of the considerable food deficit.  相似文献   
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