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951.
952.
Laparoscopy-assisted orchidopexy: an ideal treatment for children with intra-abdominal testes 总被引:2,自引:0,他引:2
Esposito C Damiano R Gonzalez Sabin MA Savanelli A Centonze A Settimi A Sacco R 《Journal of endourology / Endourological Society》2002,16(9):659-662
BACKGROUND AND PURPOSE: The investigation of a child with a nonpalpable testis is probably the most frequent indication for laparoscopy in pediatric patients. The objective of this study was to evaluate the results and advantages of laparoscopy-assisted orchidopexy performed without dividing the spermatic vessels. PATIENTS AND METHODS: During a 3-year period, 85 boys with nonpalpable testes (NPT) (91 testes overall) underwent laparoscopic diagnostic exploration. Twenty-five patients (27.4%) showed an intra-abdominal testis (IAT): 24 underwent a laparoscopy-assisted orchidopexy (LAO) without sectioning of the spermatic vessels, and one, whose inner spermatic vessels were not adequately long for LAO without tension, underwent a two-step Fowler-Stephens (FS) procedure. The technique consists of dissection and mobilization of the inner spermatic vessels and the vas deferens from the posterior peritoneum, sectioning of the gubernaculum attachments, and bringing down of the testis into the scrotum through the internal inguinal ring, if open, or through a neo-inguinal ring created medial to the epigastric vessels. RESULTS: Surgery lasted between 40 and 80 minutes (median 60 minutes). All the testes were brought down into the scrotum. There was only 1 (4%) intraoperative complication, which occurred in the second patient operated on with this procedure. He experienced an iatrogenic rupture of the spermatic vessels secondary to excessive traction. CONCLUSION: Laparoscopic orchidopexy is the logical extension of diagnostic laparoscopy for the evaluation of NPT. Concerning the technique, we believe that LAO with intact spermatic vessels could be considered the treatment of choice in the patient with IAT, as it does not affect normal testicular vascularization. Alternatively, in the case of very high IAT (more than 3 cm from IIR), an FS procedure may be considered. 相似文献
953.
Intraoperative MMC after excimer laser surgery for myopia 总被引:1,自引:0,他引:1
Maldonado MJ 《Ophthalmology》2002,109(5):826; author reply 826-826; author reply 828
954.
Retinal thickness study with optical coherence tomography in patients with diabetes 总被引:15,自引:0,他引:15
Sánchez-Tocino H Alvarez-Vidal A Maldonado MJ Moreno-Montañés J García-Layana A 《Investigative ophthalmology & visual science》2002,43(5):1588-1594
PURPOSE: To quantitatively assess retinal thickness by optical coherence tomography (OCT) in normal subjects and patients with diabetes. This study was intended to determine which retinal thickness value measured with OCT best discriminates between diabetic eyes, with and without macular edema. METHODS: OCT retinal thickness was measured by a manual technique in a total of 26 healthy volunteers (44 control eyes) and 85 patients with diabetes (148 eyes) with the clinical diagnosis of no diabetic retinopathy (45 eyes), nonproliferative diabetic retinopathy without clinically significant macular edema (CSME; 54 eyes), proliferative diabetic retinopathy without CSME (21 eyes), and 28 eyes with diabetic retinopathy with CSME. Independent predictors of the presence of CSME were quantified by using univariate and multivariate logistic regression analyses. Receiver operating characteristic (ROC) curves were generated to evaluate and compare the predictor variables. The correlation of retinal thickness measurements and visual acuity was calculated. RESULTS: There were statistically significant differences in foveal thickness between control eyes and all the other eye groups (P = 0.001). Diabetic eyes with CSME had a statistically significant greater thickness in each of the areas compared with the other groups. In a multivariate logistic regression model, foveal thickness was a strong and independent predictor of CSME (odds ratio [OR], 1.037; 95% confidence interval [CI] 1.02-1.05). The area under the ROC curve of this predictor variable was 0.94 (P = 0.001). For a cutoff point of 180 microm, the sensitivity was 93%, and specificity was 75%. Foveal thickness correlated with visual acuity in a log minimum angle of resolution (logMAR) scale (Spearman's rho = 0.9, P = 0.001). CONCLUSIONS: These results suggest that foveal thickening over 180 microm measured by OCT may be useful for the early detection of macular thickening and may be an indicator for a closer follow-up of the patient with diabetes. 相似文献
955.
In the Posner cueing paradigm, observers' performance in detecting a target is typically better in trials in which the target is present at the cued location than in trials in which the target appears at the uncued location. This effect can be explained in terms of a Bayesian observer where visual attention simply weights the information differently at the cued (attended) and uncued (unattended) locations without a change in the quality of processing at each location. Alternatively, it could also be explained in terms of visual attention changing the shape of the perceptual filter at the cued location. In this study, we use the classification image technique to compare the human perceptual filters at the cued and uncued locations in a contrast discrimination task. We did not find statistically significant differences between the shapes of the inferred perceptual filters across the two locations, nor did the observed differences account for the measured cueing effects in human observers. Instead, we found a difference in the magnitude of the classification images, supporting the idea that visual attention changes the weighting of information at the cued and uncued location, but does not change the quality of processing at each individual location. 相似文献
956.
Many models of visual processing assume that visual information is analyzed into separable and independent neural codes, or features. A common psychophysical test of independent features is known as a summation study, which measures performance in a detection, discrimination, or visual search task as the number of proposed features increases. Improvement in human performance with increasing number of available features is typically attributed to the summation, or combination, of information across independent neural coding of the features. In many instances, however, increasing the number of available features also increases the stimulus information in the task, as assessed by an optimal observer that does not include the independent neural codes. In a visual search task with spatial frequency and orientation as the component features, a particular set of stimuli were chosen so that all searches had equivalent stimulus information, regardless of the number of features. In this case, human performance did not improve with increasing number of features, implying that the improvement observed with additional features may be due to stimulus information and not the combination across independent features. 相似文献
957.
Rubio G Manzanares J Lopez-Muñoz F Alamo C Ponce G Jimenez-Arriero MA Palomo T 《Journal of substance abuse treatment》2002,23(4):131-366
Naltrexone is widely used in therapeutic programs with abstinence as a goal. However, it has been used in only a few studies aimed at reducing alcohol consumption. The purpose of this study was to evaluate the efficacy of naltrexone as an adjunct in controlled drinking programs. This was an open randomized study of 12 weeks duration that compared two therapeutic strategies: use of naltrexone in a controlled drinking program (NTX+CD) and the controlled drinking program alone (CD), without NTX. Each group comprised 30 male patients with mild alcohol dependence. During treatment, there were no differences between groups in drinking behavior, though the NTX+CD group showed significantly less craving. In the 12-month follow-up period, the NTX+CD group showed significantly fewer drinking days and heavy drinking days and less craving than the CD group. The results of this study suggest a role for naltrexone in controlled drinking programs. 相似文献
958.
We recorded the activity over one year of users of two identical teleradiology systems installed at different primary care centres. In one centre, which generated 3711 cases, the process was conducted according to the decisions made by the general practitioner (GP); in the second, which generated 3786 cases, the radiologist at the referral hospital controlled the process. In a one-year study, the number of studies created, transmitted and interpreted per day was similar in the two scenarios (14.3 vs 14.6, respectively); however, there were considerable differences in the number of images (2.2 vs 1.8, respectively) and folder volume (19.2 vs 14.3 Mbyte, respectively) per study. Also, there were differences in the time taken to create the patient folders (4 min 35 s vs 2 min 55 s, respectively) and the time taken for the radiologist to diagnose a case (3 min 32 s vs 2 min 47 s, respectively), which may be important at high workloads. The radiologist-driven scenario included 64 rejected requests (1.6% of cases) and 280 studies in which additional images were required (7.4% of cases). Whenever it is possible to choose, the radiologist-driven scenario for teleradiology appears to be preferable. A prerequisite for successful teleradiology is the availability of appropriate bandwidth and operational protocols. 相似文献
959.
Martínez-González MA Fernández-Jarne E Serrano-Martínez M Marti A Martinez JA Martín-Moreno JM 《European journal of nutrition》2002,41(4):153-160
Summary.
Background: Although an important secondary prevention trial reported an impressive protection by a Mediterranean dietary pattern on
reinfarction and cardiovascular death, scarce direct epidemiologic evidence is currently available regarding the role of the
Mediterranean diet in the aetiology of coronary heart disease. Aims: The aim of the study was to quantify the risk reduction of incident myocardial infarction provided by a Mediterranean dietary pattern. Methods: We included 342 subjects (171 patients who suffered their first acute myocardial infarction and 171 matched controls) in
a case-control study. A validated semi-quantitative food frequency questionnaire (136 items) was used. We defined an a priori Mediterranean dietary pattern. We assessed six food items that we considered protective: 1) olive oil, 2) fiber, 3) fruits,
4)vegetables, 5) fish and 6) alcohol. For each of these six dietary factors, we calculated the distribution according to quintiles
within the study and assigned each participant a score of 1 to 5 corresponding to the quintile of intake, with 1 representing
the lowest and 5 representing the highest quintile. We also estimated the quintiles of two other elements assumed to be associated
with a higher risk: 7) meat/meat products and 8) some items with high glycaemic load (white bread, pasta and rice). For these
two elements we inversely ranked the score, with 1 representing the highest and 5 representing the lowest quintile. Finally,
we summed up the eight quintile values for each participant.
A second score (post hoc pattern) was built using only a single cut-off point for these eight elements. The cut-off points for each element in this
post hoc pattern were decided according to the dose-response relationships between the consumption of each food item and the risk
of myocardial infarction observed in the analyses that used quintiles of each food item. Results: For both patterns, we found that the higher the score, the lower the odds ratio of myocardial infarction. A significant linear
trend was apparent after adjustment for the main cardiovascular risk factors. For each additional point in the a priori Mediterranean pattern (observed range: 9–38) the odds ratio (95 % confidence intervals) was 0.92 (0.86–0.98). This estimate
was 0.55 (0.42–0.73) when we used the post hoc pattern (range: 0–8). Conclusions: Our data support the hypothesis that a Mediterranean diet (that emphasizes olive oil, fiber, fruits, vegetables, fish and
alcohol and reduces meat/meat products) can be an effective measure for reducing the risk of myocardial infarction. However,
our results support the exclusion of refined cereals with a high glycaemic load as healthy elements of this pattern.
Received: 24 January 2002, Accepted: 13 May 2002 相似文献
960.
Del Arco I Navarro M Bilbao A Ferrer B Piomelli D Rodríguez De Fonseca F 《European journal of pharmacology》2002,454(1):103-104
The endogenous cannabinoid, anandamide, has been shown to attenuate naloxone-precipitated opiate withdrawal in rodents. Here we show that the spontaneous, but not the naloxone-precipitated withdrawal syndrome in morphine-dependent mice is attenuated by the inhibitor of carrier-mediated anandamide transport N-(4-hydroxyphenyl) arachidonylethanolamide (AM404) (2 and 10 mg/kg, i.p.). These results suggest that spontaneous but not opioid antagonist-precipitated withdrawal is associated with dynamic changes in endogenous cannabinoid signaling. 相似文献