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991.
Abstract: Disposition kinetics and urinary excretion of sulphadimidine were investigated in 16 dogs following a single intravenous injection (100 mg/kg body weight). Biochemical parameters including blood pH, blood glucose, plasma triglycerides and total plasma proteins of these animals were determined. The animals were injected alloxan (125 mg/kg) intravenously and when blood glucose level exceeded 300 mg%, the biochemical parameters, disposition kinetics and urinary excretion of sulphadimidine were determined again. After alloxan treatment of the dogs, there was a highly significant (P < 0.01) decrease in blood pH, increase in blood glucose and plasma triglycerides levels when compared with the pretreatment values. The alloxan diabetic dogs showed a highly significant (P < 0.01) reduction in elimination half-life (t1/2β) and apparent volume of distribution (Vd(area) and increase in overall elimination rate constant (kel), total body clearance (ClB) and percentage of sulphadimidine dose excreted in urine. In normal dogs, one-half of the intravenous dose and after alloxan treatment two-third of the dose was eliminated through urinary excretion during 48 hours after injection. This study shows that the metabolic alterations of alloxan induced diabetes in dogs, influence the drug disposition and urinary excretion which indicate the need for the adjustment of dosage regimen in such metabolic disorders.  相似文献   
992.
Epigastric pain is a common complaint throughout Africa, mostly in the form of non-ulcer dyspepsia. It has recently been suggested that Helicobacter (= Campylobacter) pylori, a bacterium that colonizes the gastric mucosa and causes type B gastritis, may be the cause of this epigastric pain. This paper reports the endoscopic, histological and bacteriological findings in 57 patients presenting with epigastric pain to the University of Maiduguri teaching hospital during one year, together with a review of the African literature. Of 57 patients, 49 had non-ulcer dyspepsia, 7 peptic ulceration and 1 carcinoma of the stomach. 93% of the patients had histological gastritis, and of these 87% were colonized with H. pylori. The bacterium was cultured from 13 patients. This high prevalence of gastritis and H. pylori has been found throughout Africa. The figures support a causative role for H. pylori in histological gastritis. At present the evidence in support of a causative role in non-ulcer dyspepsia is not strong enough to be able to recommend the routine use of anti-H. pylori therapy in patients with epigastric pain.  相似文献   
993.
994.
1. The opioid type of swim-stress induced antinociception (SIA) is mediated via mu-sites in preweanling rats and predominantly by delta-sites in postweanling animals. We have studied the effect of delay of weaning on the receptor transition of this behaviour in the developing rat. 2. Litters were weaned normally at day 21 or allowed to remain with their mothers until assessment of swim SIA. Animals were stressed by warm water (20 degrees C) swimming for 3 min periods and antinociception assessed by the tail immersion test (50 degrees C). 3. Naloxone (10 mg kg-1) partially reversed swim SIA in both 25 day old weaned and non-weaned rats. 4. Naltrindole (1 mg kg-1) partially reversed swim SIA in 25 day old weaned rats but had no effect in non-weaned animals. Naltrindole (5 mg kg-1) completely abolished swim SIA in weaned rats but was without effect in non-weaned groups. Antinociceptive responses to the mu-agonist, alfentanil (60 micrograms kg-1) were unaffected by naltrindole at 1 mg kg-1 but were partially reversed at 5 mg kg-1. 5. In 30 day old non-weaned rats, naltrindole (5 mg kg-1) abolished the swim SIA. 6. In conclusion, transition from mu to delta-receptor control of swim SIA in rat pups can be delayed by between 5 and 10 days by delay of weaning. The environmental stimulus of weaning can activate opioid receptor subtype operation of biological responses in the developing animal.  相似文献   
995.
Physical examination of a patient in whom a significant vascular injury of the extremity is suspected will almost always provide a prompt and accurate diagnosis of arterial injury. Prompt operation based on the clinical assessment, without specialized diagnostic studies, results in limb salvage and minimal morbidity.  相似文献   
996.
The effect of temperature and pregnant mare's serum gonadotropin (PMSG) was observed on the testes of Uromastix hardwicki at a time of the year (November) when the seminiferous epithelium contained abundant proliferating spermatogonia and some primary spermatocytes. This recrudescent state of the testes was maintained by keeping the animals at 20° for 10 days. But, in lizards kept at 35°, there was a marked decrease in the testis weight. The seminiferous tubules were lined mostly with Sertoli cells and a few resting types of spermatogonia. The interstitial cells were only slightly affected and there was no reduction in androgen concentrations in the testicular tissue or plasma, as measured by testosterone radioimmunoassay. At 20°, injections of 20 IU of PMSG daily for 10 days induced an increase in the number of primary spermatocytes and production of spermatids in certain regions of the tubules. In the PMSG-treated lizards kept at 35° the testes contained a single layer of resting spermatogonia placed along the basement membrane. Under these conditions PMSG failed to maintain the active state of the seminiferous epithelium. Unlike the germinal cells, the interstitial cells were markedly stimulated by PMSG at 20 or 35°. Testicular and plasma androgen levels were increased severalfold in gonadotropin-treated lizards. The elevation of androgen levels as a result of PMSG stimulation was higher in lizards kept at 35°. It is suggested that in Uromastix hardwicki, the germinal epithelium responds differentially to PMSG treatment at the two different temperatures and that the activity of the interstitial cells is not inhibited by hyperthermia.  相似文献   
997.
998.
999.
This study examined the differences between full‐time self‐employed and organizationally employed individuals in Canada (n = 248) and Pakistan (n = 306) in terms of overall burnout and its three dimensions (emotional exhaustion, depersonalization and lack of accomplishment), turnover intentions and non‐work satisfaction. Data were collected by means of a structured questionnaire from Canadian employees in Montreal and Pakistani employees in Lahore. One‐way analysis of variance and multivariate analysis of variance were used to analyse the data. The self‐employed reported significantly higher overall burnout, emotional exhaustion, lack of accomplishment, non‐work satisfaction and turnover intention than the organizationally employed in both countries. No significant differences were found between self‐employed and organizationally employed in terms of depersonalization in both countries. Results are discussed in light of previous empirical evidence on self‐employment and the quality of work and non‐work life from cross‐cultural perspectives. Copyright © 2007 John Wiley & Sons, Ltd.  相似文献   
1000.
Management of osteochondral lesions of the joint has been difficult, because articular cartilage has a poor healing capacity as a result of its lack of vessels, nerve supply, and its isolation of systemic regulation. Although a lot of basic research and surgical treatments for cartilage repair have focused on osteochondral lesions in the knee joint, orthopedic surgeons have recently diverted their attention to osteochondral lesions in the ankle joint, partly because of the widespread introduction of arthroscopy in ankle surgery. There have been many attempts to treat articular cartilage defects in the ankle joint as well as in the knee joint. However, no treatment has achieved efficient healing with hyaline cartilage. Recently, tissue engineering technique for cartilage repair has been gaining much attention in the orthopedic field. In this study, we reported on a patient with osteochondritis dissecans of the talar dome, successfully treated by transplantation of tissue-engineered cartilage made ex vivo using atelocollagen gel and low tibial osteotomy.  相似文献   
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