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991.
Background and Aims:  To investigate the utility of a new method of carrying out esophageal manometry using a narrow gauge manometry catheter via a transnasal endoscope.
Methods:  The Frequency Scale for the Symptoms of gastroesophageal reflux disease (GERD) (FSSG), a GERD-specific questionnaire, was given to 45 subjects. Subjects 
underwent transnasal endoscopy with three dry and three wet (3 mL water) swallows. Direct observations of the primary peristaltic wave and peristaltic pressure measurement were conducted simultaneously.
Results:  Endoscopic observation of lower esophageal motility associated with swallowing revealed dilatation of the esophageal lumen after swallowing, followed by contraction in association with the primary peristaltic wave. The peristaltic pressure was significantly lower with increased FSSG scores for dry swallows ( r  = −0.347, P  = 0.0212), but no significant correlation was seen for wet swallows.
Conclusions:  The significant negative correlation between reflux symptoms and peristaltic pressure in dry swallows was thought to be that reduced pressure immediately rostral to the lower esophageal sphincter leads to decreased clearance following gastric acid reflux, playing a large part in the onset of symptoms.  相似文献   
992.
In early postnatal life, sensory inputs deeply influence development as well as function of the brain. Plasticity of synaptic transmission including its experimentally induced form, long‐term potentiation (LTP), is affected by sensory deprivation in neocortex. This study is devoted to assess if dark rearing and a dark phase synthesized hormone melatonin influence LTP in the hippocampus, an area of brain involved in learning and memory. In vivo experiments were carried out on two groups of 45‐days‐old male Wistar rats kept in standard 12‐h light/dark condition [light reared (LR) tested during the light phase] or in complete darkness [dark reared (DR)] since birth to testing. Each group, in turn, was divided to two, vehicle‐ and melatonin‐treated, groups. Stimulating the Schaffer collaterals of CA3 area of hippocampus extracellular postsynaptic potentials (EPSPs) were recorded in the CA1 area. Having the stable baseline responses to the test pulses, the hippocampus was perfused by either vehicle or 2 μg melatonin and EPSPs were recorded for 30 min. Then, for induction of LTP, the tetanus was applied to the Schaffer collaterals and the field potentials were pooled for 120‐min post‐tetanus. The light deprivation resulted in a significant augmentation in the amplitude of baseline responses. Also, we observed a melatonin‐induced increase in amplitude of the baseline recordings in either LR or DR animals. Tetanic stimulation elicited LTP of EPSPs in both LR and DR groups, robustly in the former where it lasted for about 90 min. Generally, melatonin inhibited the production of LTP in the two groups especially in the LR animals leading to a noticeable depression. We concluded that higher level of neuronal activity in the DR rats gives rise to a lower level of LTP. Weaker effect of melatonin on blocking the potentiation of post‐tetanus EPSPs in the DR rats may be the result of a desensitization of melatonin receptors due to chronically increased levels of this hormone in the visually deprived rats. © 2009 Wiley‐Liss, Inc.  相似文献   
993.
Vascular lesions such as hemangiomas can be found in the oral cavity. Some therapeutic modalities can be used in the treatment of these lesions and Nd:YAG 1064 nm long pulse laser shows good results with easy application, fewer complications and satisfactory results. This study describes the technique and outcome of a case of hemangioma located on the tongue treated with Nd:YAG laser.  相似文献   
994.
Background and Aims: In the management of peptic ulcer bleeding, the benefits of second‐look endoscopic treatment with thermal coagulation or injections in controlling recurrent bleeding is unsure. This study set out to compare efficacy of routine second‐look endoscopy with treatment using either thermal coagulation or injections versus single endoscopy by pooling data from published work. Methods: Full publications in the English‐language published work as well as abstracts in major international conferences were searched over the past 10 years, and six trials fulfilling the search criteria were found. Outcome measurements included: (i) recurrent bleeding; (ii) requirement of surgical intervention; and (iii) mortality. We examined heterogeneity of trials and pooled the effects by meta‐analysis. The quality of studies was graded according to the prospective randomization, methods of patient allocation, the list of exclusion criteria, outcome definitions and the predefined salvage procedures for uncontrolled bleeding. Results: Among 998 patients recruited in these five randomized trials, 119 received routine second‐look endoscopy with thermal coagulation, and 374 received second‐look with endoscopic injection and 505 had single endoscopic therapy. Less recurrent bleeding was reported after thermal coagulation (4.2%) than single endoscopy (15.7%) (relative risk [RR] = 0.29; 95% confidence interval [CI] = 0.11–0.73), but no reduction was reported for the requirement of surgical intervention and all‐cause mortality. Injection therapy did not reduce re‐bleeding (17.6%) when compared to single endoscopy (20.8%; RR = 0.85; 95% CI = 0.63–1.14), requirement for surgery and mortality. Conclusion: Routine second‐look endoscopy with thermal coagulation, but not injection therapy, reduced recurrent peptic ulcer bleeding. There is no proven benefit in reducing surgical intervention and overall mortality.  相似文献   
995.
996.
目的分析反流性食管炎患者的临床及内镜特点。方法回顾性分析我院消化内镜中心诊治的反流性食管炎767例患者的性别、年龄,并且按照洛杉矶标准(LosAngeles classifica-tion,简称LA)进行分级。结果 767例反流性食管炎患者中,男577例,女190例,男女比例3.04∶1,患者发病高峰年龄41~60岁。结论反流性食管炎男性患者检出量多于女性患者,反流性食管炎的发病主要以A、B级为主,A、B级患者占94.1%。  相似文献   
997.
Aim: The major limitation of capsule endoscopy (CE) has been the lack of a standardized and validated severity scale for mucosal injury. The aim of the present study was to verify the usefulness of quantifying small bowel mucosal changes associated with giving low‐dose aspirin (LDA) using a CE scoring index. Methods: The CE score for small bowel mucosal injury was investigated to evaluate the severity of mucosal injury. Healthy volunteers and patients suspected of having small bowel disease were recruited for this study. The short‐term LDA group (V + S‐LDA group) consisted of volunteers who took low‐dose aspirin for 14 days; this group was then compared with healthy volunteers who did not receive LDA treatment (V‐Control group). The long‐term LDA group (L‐LDA group) consisted of patients with at least a 3‐month history of daily LDA use; this group was compared with non‐users of LDA (P‐Control group). Results: The CE score was significantly higher in the V + S‐LDA group than in the V‐Control group. In the V‐Control group, almost all the subjects were categorized as exhibiting a ‘normal’ change. ‘Mild’ changes were observed significantly more frequently in the V + S‐LDA group than in the V‐Control group. The CE score was significantly higher in the L‐LDA group than in the P‐Control group. ‘Mild’ or ‘moderate or severe’ changes were observed significantly more frequently in the L‐LDA group than in the P‐Control group. Conclusion: The CE scoring system was useful for evaluating LDA‐associated small bowel mucosal disease activity and for objectively scoring the small bowel inflammatory disease state.  相似文献   
998.
Although it is well known that cadmium (Cd) causes adverse effects on male rat reproductive organs, few studies have quantified alterations caused by its low doses. Quantification of these alterations, especially in the testis, was measured using morphometry. A single dose of cadmium chloride (1 or 1.2 mg/kg BW) was injected i.p. in adult rats, killed after 7 or 56 days. The lower dose caused slight alterations as measured by morphometrical analysis. The higher dose caused significant reduction in testis and epididymis weight, gonadossomatic index and length of seminiferous tubule (ST) after 7 and 56 days. Cadmium significantly reduced the ST diameter after 56 days. Decreased volume density of ST, after 7 and 56 days, was accompanied by an increase in interstitium volume density. The damage caused by the dose of 1.2 mg/kg can be clearly observed with light microscope. After 7 days, the tubule lumens were filled with degenerated germ cells and multinucleated spermatid aggregates. Vacuolization of the seminiferous epithelium was also observed. After 56 days, increased damage resulted in vacuolated ST, consisting only of Sertoli cells. Scanning electron microscopy examination of the testis showed that, in the group cadmium treated (1.2 mg/kg) and killed after 56 days, the interstitial tissue presents a compact and fibrous appearance with absence of fenestrae. The seminiferous epithelium height diminished and the absence of spermatozoa can be noted. The results show that a very small difference of Cd dose causes a sudden increase in testicular damage, apparently overpowering this tissue’s natural defences.  相似文献   
999.
Small bowel pseudomelanosis is a rarely reported clinical entity characterized by brown pigmentation of small bowel mucosa. The authors describe two cases, both with iron deficiency anemia, one of an 81‐year‐old female patient submitted for capsule endoscopy that revealed a brown pigmentation of all small bowel mucosa and another of an 81‐year‐old male whose retrograde double‐balloon enteroscopy revealed a diffuse brown pattern of small bowel mucosa. Ileal biopsies confirmed intense iron deposition in the macrophages of the lamina propria. Both patients were on oral iron therapy and the second one had a previous double‐balloon enteroscopy, 2 years earlier, which revealed only ileal angiodysplasias. These two cases demonstrate the importance of two new endoscopic methods for diagnosis of small bowel pseudomelanosis, the rarity of such an entity and its close relation with oral iron therapy.  相似文献   
1000.
Ultraviolet (UV) irradiation is a common disinfection option for water treatment in the developed world. There are a few systems installed in developing countries for point-of-use treatment, but the low-pressure mercury lamps currently used as the UV irradiation source have a number of sustainability issues including a fragile envelope, a lifetime of approximately one year, and they contain mercury. UV light emitting diodes (LEDs) may offer solutions to many of the sustainability issues presented by current UV systems. LEDs are small, efficient, have long lifetimes, and do not contain mercury. Germicidal UV LEDs emitting at 265 nm were evaluated for inactivation of E. coli in water and compared to conventional low-pressure UV lamps. Both systems provided an equivalent level of treatment. A UV-LED prototype was developed and evaluated as a proof-of-concept of this technology for a point-of-use disinfection option, and the economics of UV-LEDs were evaluated.  相似文献   
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