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991.
Metoclopramide (MET) has long been used as a neuroleptic and antiemetic drug in clinical practice. Motor impairment and dyskinesia have been reported in some patients following chronic treatment with MET. Occasionally, the adverse symptoms may appear even after acute exposure to MET in more susceptible population (such as elderly individual) or due to concomitant exposure to MET and certain neurotoxins. Iminodipropionitrile (IDPN), a prototype nitrile toxin, has been shown to produce dyskinetic syndrome in rodents. This study reports the effect of concomitant exposure of rats to MET and IDPN on behavioral abnormalities in rats namely excitation, circling and chorea (ECC) syndrome. Four groups of female Wistar rats (aged 3 months) were given MET (0, 10, 40 and 80 mg/kg, i.p., for 11 days) 30 min before IDPN (100 mg/kg, i.p. for 8 days). Two additional groups of rats were treated with either saline (control group) or 80 mg/kg of MET (drug alone group). The animals were observed for neurobehavioral abnormalities including dyskinetic head movement, circling, tail hanging, air righting reflex and contact inhibition of righting reflex. Horizontal and vertical locomotor activities and fore limbs grip strength were also measured. On day 12, the animals were sacrificed and brains were collected for biochemical analysis. MET significantly and dose-dependently protected the animals against IDPN-induced ECC syndrome, motor impairment and deficiency in grip strength. MET also protected the animals against IDPN-induced oxidative stress.  相似文献   
992.
Two simple and sensitive validated spectrophotometric methods have been described for the assay of nicorandil in drug formulations. Method A is based on the reaction of the drug with phloroglucinol-sulfanilic acid reagent in sulfuric acid medium to give yellow-colored product, which absorbs maximally at 425 nm. Method B uses the oxidative coupling of 3-methyl-2-benzothiazolinone hydrazone hydrochloride (MBTH) with DL- 3,4 - dihydroxyphenylalanine (DL-dopa) in the presence of nicorandil as oxidant in sulfuric acid medium to form an intensely colored product having maximum absorbance at 530 nm. Beer's law is obeyed in the concentration range 2.5 to 50.0 and 1.0 to 15.0 microg mL(-1) with methods A and B, respectively. Both methods have been successfully applied for the analysis of drug in pharmaceutical formulations. The reliability and the performance of the proposed methods are established by point and interval hypothesis and through recovery studies. The experimental true bias of all samples is smaller than +/-2%.  相似文献   
993.
Genotoxicity of acrylamide and glycidamide   总被引:1,自引:0,他引:1  
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994.
BACKGROUND: The best treatment option for patients with locally advanced esophageal carcinoma has not yet been determined, especially because the benefits of esophagectomy after neoadjuvant chemoradiotherapy are still controversial. We report the results of a retrospective cohort comparison of definitive chemoradiotherapy without surgery (CRT) versus neoadjuvant chemoradiotherapy followed by planned surgery (CRTS) in patients with advanced esophageal squamous cell carcinoma (SCC). MATERIALS AND METHODS: Between January 1991 and December 2002, 67 patients were enrolled in this study. Fifty of the 67 patients were considered to have inoperable tumors due to distant organ metastasis, distant lymph node metastasis, severe organ dysfunction or rejection of surgery by the patient and received CRT, while the remaining 17 patients were treated with CRTS. The clinical responses of the primary tumors were evaluated. RESULTS: In the 50 CRT patients, the one- and 2-year survival rates were 33.8% and 20.2%, respectively, and the median survival time (MST) was 13.5 months. In the 17 CRTS patients, the response rate (CR + PR) was 76.5%, and the pathological complete response (pCR) rate was 29.4%. Their one- and 2-year survival rates were 61.6% and 35.9%, respectively, and the MST was 24.4 months. The survival rates of the CRT patients were lower than those of the CRTS patients (p = 0.1288). When the 12 patients with distant organ metastases were removed from the CRT group, the one- and 2-year survival rates of the remaining 38 patients were 36.5% and 24.1%, respectively, and the MST was 14.7 months. The survival rates of these 38 CRT patients without distant organ metastases were similar to those of the 12 CRTS patients in the pathological partial response (pPR) group (p = 0.6279). CONCLUSION: This retrospective cohort comparison of CRT versus CRTS demonstrated that there may not be any survival benefit from the addition of surgery in the pPR group for advanced esophageal carcinomas. For patients with a poor response to neoadjuvant chemoradiotherapy, we suggest that the addition of chemoradiotherapy, instead of planned esophagectomy, may show a similar survival rate to definitive CRT. Thus, a large series of a randomized control study will be required to confirm the benefit of surgery after chemoradiotherapy.  相似文献   
995.
996.
The objectives in this epidemiology review are to measure and report the extent of morbidity and mortality due to tuberculosis (TB), the proportion of new sputum smear positive cases in districts and the status of cohort analysis as of 1999. As for leprosy, the main objective is to determine morbidity and the treatment outcomes of Multiple Drug Therapy (MDT). Based on the results obtained, a comprehensive action plan for prevention, control and monitoring of tuberculosis and leprosy cases and patients is being produced and implemented throughout the state. The analysis concentrated on patients diagnosed at all out-patient units and admitted in all of the state's hospitals. The patient particulars were recorded using a standardized format based on TB and Leprosy Health Management Information System (TB HMIS). TB was the second highest by notification of communicable diseases in Malaysia in 2001. 29% or about one-third of the national TB cases are from Sabah. However, it has been noted that there was an average decline of 2.6% in annual notification since 10 years ago to date. There was also a reduction of 11.4% in 2001 as compared to annual notification in 2000. Immigrants contribute more than 24% in detection of new cases since 1990. Treatment success rate in term of completion of treatment to date is 82%. Mortality rate has steadily declined from 14 deaths to 7 deaths per 100,000 population. Leprosy in Sabah also contributes to 30% of the yearly total caseload of Malaysia and has the highest notification rate of 2 per every 100,000 population as compared to other states. The average registered leprosy cases over the past 5 years are 239 cases and the prevalence rate is 0.7/10,000 population. The state has successfully achieved its goal to decrease leprosy as per the World Health Organization (WHO) goal of yearly overall prevalence rate of less than 1 case for every 10,000 population. However, the districts of Kudat, Tawau, Lahad Datu, Kota Kinabalu and Semporna are still within the prevalence rate of more than one per 10,000 population. This review highlights some interesting findings which can be incorporated into the State and Districts action plans and strategies. It is also noted that in order to translate National Plans and Strategies into effective action at the community level, health workers need relevant up-to-date knowledge of the pattern of health and disease, and of their determinants, in each district. The Sabah Health Department continues to organize and support programs related to management and control of tuberculosis and leprosy to progressively reduce the incidence of these diseases in the community by breaking the chain of transmission of Mycobacterium tuberculosis and M. leprae, respectively.  相似文献   
997.
998.
The human leukocyte antigen (HLA) region located on chromosome 6p encodes the highly polymorphic, classical class I and II genes essential for normal lymphocyte function; it also encodes a further 224 genes. Many early studies investigating this region were limited by small sample size, poor statistical methodology, population stratification and variable disease definition. Although more recent studies have improved study design, investigators are still challenged by the complex patterns of linkage disequilibrium across this gene-dense region, and by the disease heterogeneity characteristic of all genetically complex disorders. However, a number of important observations have emerged from recent studies: (1) the HLA harbours gene(s) that determine susceptibility to colonic inflammation in both ulcerative colitis (UC) and Crohn's disease (CD); (2) most of the specific associations with UC and CD appear to differ; (3) associations between different ethnic groups differ; (4) markers in the HLA might predict the course of disease and the development of complications, notably the extraintestinal manifestations of disease.  相似文献   
999.
A 2‐year‐old Saudi boy was seen in our dermatology clinic with symmetrical, brown, linear macules over the legs, trunk, and arms ( Figs 1–3 ). He was a product of a full‐term vaginal delivery following an uneventful first pregnancy in a 22‐year‐old mother. The birth weight was 2.3 kg. The hyperpigmented macules followed the lines of Blaschko and were noticed a few months after birth; they had enlarged with body growth until the age of 18 months. There was no family history of a similar condition and the boy's parents were unrelated. No blistering or inflammatory changes preceded the hyperpigmentation. The palms, soles, nails, scalp, mucous membranes, and teeth were normal. In addition to the hyperpigmented macules, the patient started to have generalized convulsions at the age of 2 months.
Figure 1 Open in figure viewer PowerPoint Linear hyperpigmented macules following the lines of Blaschko  相似文献   
1000.
PURPOSE: To evaluate the effects of sex and estrus cycle on biphasic anticonvulsant and proconvulsant modulation of seizure threshold by morphine. METHODS: The threshold for the clonic seizures (CST) induced by acute intravenous administration of gamma-aminobutyric acid (GABA)-antagonist pentylenetetrazole (PTZ) was assessed in male and female mice. Estrus cycle was assessed by vaginal smears. The effect of removing circulating sex hormones was assessed by gonadectomy. RESULTS: At baseline, diestrus females had a higher CST compared with males and estrus females. Morphine at lower doses (0.5-3 mg/kg) had a significant anticonvulsant effect in males and estrus females compared with that in vehicle-treated controls, whereas female mice in diestrus phase showed a relative subsensitivity to this effect. Morphine at higher doses (30 and 60 mg/kg) significantly decreased CST in males and diestrus females, with less relative effect in estrus mice. In both phases, morphine exerted stronger effects in males compared with females. Ovariectomy brought the baseline CST to the male level and resulted in significant expression of both phases of morphine effect but did not abolish the sex difference in responsiveness to morphine. CONCLUSIONS: The biphasic modulation of seizure threshold is subject to both constitutive sex differences in sensitivity to morphine and hormonal fluctuations during the estrus cycle.  相似文献   
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