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991.
The International Association for the Study of Pain, has defined pain as “an unpleasant sensory and emotional experience connected with actual or potential tissue damage or described in terms of such damage”. It was thought that the newborn baby does not experience pain because of incompletely developed nervous system. However, it has been shown that neurological system known to be associated with pain transmission and modulation, is intact and functional. A study was conducted in our center to study the analgesic effect of administration of oral glucose in various concentrations, in neonates undergoing heel punctures, for collection of blood for investigations. This was compared with the analgesic effects of breast milk (which contains lactose). 125 full term normal neonates with no history of birth asphyxia or underlying neurological abnormality, requiring heel punctures for collection of blood for various investigations were selected for the study. They were matched for gestational age, birth weight and sex distribution and divided into 5 groups of 25 each. One group comprised control subjects and was administered sterile water. 3 groups were administered 1 ml of varying strengths of glucose solutions i.e. 10%, 25% and 50% respectively. The last group was given 1 ml of expressed breast milk (EBM). Prior to heel pricks, state of arousal, baseline heart rate (HR) and transcutaneous oxygen saturation (SpO2) were recorded by pulse oximeter in each neonate. Autolet, a mechanical device for capillary sampling, was used for heel pricks to give equal strength of painful stimulus in each procedure. Audio tape recorder was used to record the cry. The oral solution was administered slowly over 30 seconds by means of a syringe placed in the mouth. Heel puncture was done after 2 minutes, taking all aseptic precautions. HR and SpO2 were monitored using pulse oximeter. Pain response was assessed, by recording duration of crying, change in HR, change in SpO2 and facial action score after the procedure. Mean duration of cry and total cry over 5 minutes was significantly less in groups given 25% and 50% glucose solutions as compared to the control group and babies given EBM. Difference in mean increase in HR, fall in SpO2 were statistically significant between control group, EBM group and neonates given 25% and 50% glucose solutions respectively. Compared to control group, all other administered solutions (10%, 25%, 50% glucose and EBM) were found to reduce physiological and behavioral responses in neonates undergoing heel punctures. 25% and 50% glucose solutions were found to have maximal analgesic effect and both were found to be equally effective. EBM and 10% glucose solution have an equal analgesic effect but less than 25% or 50% glucose. This simple, cheap and safe method of oral analgesia can be easily used in neonates undergoing heel prick procedures during routine neonatal care.Key Words: Analgesic effect, Breast milk, Glucose, Neonates 相似文献
992.
Shahrzad S Quayle L Stone C Plumb C Shirasawa S Rak JW Coomber BL 《Cancer research》2005,65(18):8134-8141
Mutation of the K-ras gene is one of the most common genetic alterations in solid tumors, including colorectal cancer. The relatively late emergence of K-ras mutations in colorectal cancer is particularly striking in the class of mismatch repair-deficient tumors associated with early-onset microsatellite instability. We, therefore, tested the hypothesis that the microsatellite instability phenotype itself does not efficiently trigger K-ras mutations in colorectal cancer cells, but rather that tumor-associated microenvironmental conditions (e.g., hypoxia and hypoglycemia) contribute to this event by modulating genetic instability. We examined K-ras(G13D) mutation using PCR-RFLP analysis in two different microsatellite instability colorectal cancer cell lines (HCT116 and DLD-1) and their variants in which the mutant (but not the wild-type) K-ras allele has been genetically disrupted (Hkh-2 and Dks-8). We found K-ras(G13D) mutation to occur at far greater incidence in cells derived from xenografted tumors or exposed to conditions of combined hypoxia and hypoglycemia in vitro. Interestingly, this mutagenesis was neither enhanced by induced oxidative damage nor prevented by the antioxidant vitamin E. Moreover, the accumulation of K-ras mutations was paralleled by down-regulation of the key mismatch repair protein MSH2 in xenografted tumors, particularly in hypoperfused areas and under hypoglycemic conditions (in vitro). In contrast, the microsatellite stable colorectal cancer cell line Caco-2 neither accumulated K-ras mutations nor showed down-regulation of MSH2 under these conditions. Thus, our study suggests that ischemia may not simply select for, but can actually trigger, increased mutation rate in crucial colorectal cancer oncoproteins. This finding establishes a novel linkage between genetic instability, tumor ischemia, and genetic tumor progression and carries important implications for applying anticancer therapies involving tumor hypoxia (e.g., antiangiogenesis) in microsatellite instability cancers. 相似文献
993.
Remirez D Tafazoli S Delgado R Harandi AA O'Brien PJ 《Drug metabolism and drug interactions》2005,21(1):19-29
Vimang is an aqueous extract of Mangifera indica used in Cuba to improve the quality of life in patients suffering from inflammatory diseases. In the present study we evaluated the effects of Vimang at preventing reactive oxygen species (ROS) formation and lipid peroxidation in intact isolated rat hepatocytes. Vimang at 20, 50 and 100 microg/ml inhibited hepatocyte ROS formation induced by glucose-glucose oxidase. Hepatocyte cytotoxicity and lipid peroxidation induced by cumene hydroperoxide was also inhibited by Vimang in a dose and time dependent manner at the same concentration. Vimang also inhibited superoxide radical formation by xanthine oxidase and hypoxanthine. The superoxide radical scavenging and antioxidant activity of the Vimang extract was likely related to its gallates, catechins and mangiferin content. To our knowledge, this is the first report of cytoprotective antioxidant effects of Vimang in cellular oxidative stress models. 相似文献
994.
Michel Labrecque John Pile David Sokal Ramachandra CM Kaza Mizanur Rahman SS Bodh Jeewan Bhattarai Ganesh D Bhatt Tika Man Vaidya 《BMC urology》2005,5(1):1-9
Background
Simple ligation of the vas with suture material and excision of a small vas segment is believed to be the most common vasectomy occlusion technique performed in low-resource settings. Ligation and excision (LE) is associated with a risk of occlusion and contraceptive failure which can be reduced by performing fascial interposition (FI) along with LE. Combining FI with intra luminal thermal cautery could be even more effective. The objective of this study was to determine the surgical vasectomy techniques currently used in five Asian countries and to evaluate the facilitating and limiting factors to introduction and assessment of FI and thermal cautery in these countries.Methods
Between December 2003 and February 2004, 3 to 6 major vasectomy centers from Cambodia, Thailand, India, Nepal, and Bangladesh were visited and interviews with 5 to 11 key informants in each country were conducted. Vasectomy techniques performed in each center were observed. Vasectomy techniques using hand-held, battery-driven cautery devices and FI were demonstrated and performed under supervision by local providers. Information about interest and open-mindedness regarding the use of thermal cautery and/or FI was gathered.Results
The use of vasectomy was marginal in Thailand and Cambodia. In India, Nepal, and Bangladesh, vasectomy was supported by national reproductive health programs. Most vasectomies were performed using the No-Scalpel Vasectomy (NSV) technique and simple LE. The addition of FI to LE, although largely known, was seldom performed. The main reasons reported were: 1) insufficient surgical skills, 2) time needed to perform the technique, and 3) technique not being mandatory according to country standards. Thermal cautery devices for vasectomy were not available in any selected countries. Pilot hands-on assessment showed that the technique could be safely and effectively performed by Asian providers. However, in addition to provision of supplies, introducing cautery with FI could be associated with the same barriers encountered when introducing FI in combination with LE.Conclusion
Further studies assessing the effectiveness, safety, and feasibility of implementation are needed before thermal cautery combined with FI is introduced in Asia on a large scale. Until thermal cautery is introduced in a country, vasectomy providers should practice LE with FI to maximize effectiveness of vasectomy procedure. 相似文献995.
Warts are common in renal allograft recipients, with a reported incidence of warts ranging from 24% to 100%. These patients also demonstrate an accelerated course from wart to carcinoma. Although the histologic appearance of common warts is predictable in immunocompetent patients, this has not been shown in renal allograft recipients. The purpose of the study was to evaluate the histopathologic findings of warty lesions in renal allograft recipients and to determine the degree of dysplasia or malignant transformation in such lesions. We examined 55 renal allograft recipients for warty lesions. We obtained biopsy specimens from 50 lesions that appeared on clinical examination to be common warts and evaluated their histopathologic features. Median time from transplantation was 49 months (<5 years). All patients were treated with cyclosporine, azathioprine, and prednisolone. Among 55 renal allograft recipients, 17 patients (30.9%) had warty lesions. Forty-seven lesions (94%) showed changes of verruca vulgaris on histologic examination, and only three lesions (6%) showed warts with mild dysplasia. No malignant transformation was reported. Our findings were in contrast to a previous, similar study. This may be attributable to the relatively short period from transplantation to biopsy in our patients. 相似文献
996.
继前报后,又从异叶梁王茶[Nothopanax davidii(France)Harms]树皮中分离得到两种五环三萜皂甙。经化学和波谱(IR,1HNMR,~(13)CHMR,1H-1HCOSY,13C-1H COSY,MS)分析,分别鉴定为3-O-α-(2’,4’-O-二乙酰基)-L-吡喃阿拉伯糖-3β-羟基齐墩果-12-烯-28,29-双羧酸-28-O-[α-L-吡喃鼠李糖(1-4)-β-D-吡喃葡萄糖(1—6)-β-D-吡喃葡萄糖]酯甙(Ⅲ),命名为异叶梁王茶甙Ⅲ和3-O-β-(2-O-乙酰基)-D-吡喃木糖-3β-羟齐墩果-12-烯-28,29-双羧酸甙(Ⅳ),命名为异叶梁王茶甙Ⅳ。这两种皂甙均系首次从植物中分出的新化合物。 相似文献
997.
CT of the pulmonary nodule: a cooperative study 总被引:31,自引:0,他引:31
Zerhouni EA; Stitik FP; Siegelman SS; Naidich DP; Sagel SS; Proto AV; Muhm JR; Walsh JW; Martinez CR; Heelan RT 《Radiology》1986,160(2):319-327
To evaluate the role of computed tomography (CT) in the investigation of pulmonary nodules, a special reference phantom that enabled CT densitometric measurements independent of variations between scanners and patients was used in ten institutions. A total of 384 nodules not considered calcified by conventional methods were examined; 118 (31%) proved to be benign, and in 65 of these (55%), unsuspected calcification was demonstrated. In 28 of the 65, definite calcification could be identified on thin-section CT scans by simple inspection of the scans at narrow windows. In the remaining 37, presence of calcification could not be clearly established without comparison with the reference CT number from the calibration phantom. CT was most effective in establishing the benignancy of nodules 3 cm or less in diameter and those with discrete or smooth margins. CT rarely yields a confident diagnosis of benign disease in larger nodules and in those with irregular or spiculated borders. After review of prior spot radiographs, low kilovolt peak spot radiographs, and conventional tomograms, the authors conclude that thin-section CT aided by a reference phantom in equivocal cases should be an integral part of the diagnostic approach to the pulmonary nodule. 相似文献
998.
999.