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Jerry  A.  Shields  Ralph  C.  Eagle  Jr  Carol  L  Shields  Brian  P.  Marr  李学民 《美国医学会眼科杂志(中文版)》2006,18(1):33-39
众所周知,视网膜星形细胞瘤常伴有结节性硬化的表现。视网膜星形细胞瘤一般是发生在视网膜神经纤维层的无蒂轻度隆起性病变。临床上可以是单侧发生,也可以是双侧发生。可以单个病灶,也可以多个病灶。可以是透明的,也可以是不透明的。可以有钙化,也可以没有钙化。视网膜星形细胞瘤相对固定的伴有眼内结节性硬化,很少表现为浸润性增长。在很少的情况下视网膜星形细胞瘤可以表现出浸润性增长,造成局部严重并发症。  相似文献   
3.
BACKGROUND: Solid-organ transplantation has become the treatment of choice for patients with end-stage renal disease, end-stage liver failure, and some patients with type 1 diabetes mellitus. Similarly, surgical expertise and mechanical improvements have led to significant advances in laparoscopic surgery. Laparoscopic interventions are sometimes not pursued in transplant recipients due to the lack of strong supporting evidence for the use of laparoscopic techniques in these patients. METHODS: Using an extensive literature search, we review herein the available data on the utility of laparoscopic interventions in transplant recipients, with particular attention to the risks and benefits, indications, and contraindications for this complex patient population. RESULTS: Although randomized trials are few, multiple case reports indicate that many transplant recipients have benefited from laparoscopic interventions. CONCLUSION: The well-known benefits of laparoscopy could be extended to transplant recipients.  相似文献   
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Recently we have reported that injections of d-amphetamine into the nucleus accumbens enhanced the number of switches to cue-directed behaviours without an effect on the number of switches to non-cue-directed behaviours in a swimming test. In the present study we investigated to what extent this effect is mediated via the dopaminergic system in the nucleus accumbens. For that purpose drugs selective for D1- and D2-receptors were studied in this swimming test. It was found that the selective D2-agonist LY 171 555 (50 ng/0.5 microliters) enhanced the number of different cue-directed behaviours. The selective D2-antagonist raclopride (50 ng/0.5 microliters) decreased it. Furthermore an ineffective dose of raclopride attenuated the effect of LY 171 555. Both the selective D1-antagonist SCH 23390 (400 ng/0.5 microliters) and the selective D1-agonist SKF 38393 (50-400 ng/0.5 microliters) decreased the number of different cue-directed behaviours. The effect induced by SCH 23390 could not be blocked by SKF 38393. Similarly the effect induced by SKF could not be attenuated by SCH 23390. These data point to a role for dopamine D2-receptors in the ability to switch to cue-directed behaviours. The present findings do not yet allow the conclusion that D1-receptors are involved.  相似文献   
6.
The possible effect of Government Consumption (a component of Gross Domestic Product (GDP)) on attainment of the hunger Millennium Development Goal (MDG1) was analyzed by evaluating the effect of macroeconomic, social, demographic and policy variables on average undernourished population. Eighty-four developing countries with data available on undernourished population were included in an ecological study. Regression models were applied to explore possible determinants of Undernourished between 1990 and 2004 and consequent achievement of the projected 2004 MDG1. In 2004, 1.4% of the overall undernourished population in the studied countries [70.16 million people] was in excess of the projected level required to meet MDG1. The multiple linear regression showed significant associations between Undernourished and poverty levels, the Gini Index, rural population and Government Consumption. The multiple logistic regression showed significant associations between achievement of projected 2004 MDG1 levels and Government Consumption and the Gini Index. The significant associations between Undernourished and Government Consumption suggest that the effects of GDP components on social conditions call for more thorough research and that policymakers such as governments and international financial institutions need to ensure that changes in distributive and redistributive policies do not negatively affect the possibility of achieving MDG1.  相似文献   
7.
Arthroscopic acromioplasty. Technique and results   总被引:3,自引:0,他引:3  
Of forty-four patients who were treated by arthroscopic acromioplasty from July 1984 through August 1986, forty were available for analysis. The average age was 43.2 years, and 86 per cent of them had participated regularly in sports but were disabled due to symptoms of impingement. All patients had had a minimum of six months of non-operative therapy. The final diagnoses, which were based on the findings at arthroscopy and on clinical examination, plain radiographs, and arthrograms, were Stage-II impingement in twenty-four patients, a partial-thickness tear of the rotator cuff in six, and a full-thickness tear of the rotator cuff in ten. The shoulders were scored before the operation and again at follow-up. Preoperatively, thirty-six shoulders were rated as poor and four, as fair. After a minimum follow-up of twelve months (average, seventeen months), the scores had increased in all but one patient. The result was rated good or excellent in twenty-nine (73 per cent) of the forty patients: twenty of the twenty-four who had Stage-II impingement, four of the six who had a partial-thickness tear, and six of the ten who had a full-thickness tear. The over-all average time to return to work was nine days, and the average time to return to sports was 2.4 months. Of the thirty-three patients who had participated in sports, twenty-five (76 per cent) had returned to sports activity at the time of the most recent follow-up. The average time until full recovery was 3.8 months. There were no complications, and, over-all, thirty-eight (92 per cent) of the forty patients were satisfied with the result. In four patients, the result was a failure, and three of the four had a reoperation that relieved the symptoms.  相似文献   
8.
A Soutar  C Harker  A Seaton  M Brooke    I Marr 《Thorax》1994,49(4):352-356
BACKGROUND--There is widespread concern that the cultivation of oilseed rape leads to seasonal epidemics of respiratory symptoms in populations living in the neighbourhood, and it has been suggested that the plant is a potent allergen. A study was therefore undertaken to determine the prevalence of seasonal symptoms in rural populations close to and far from areas of oilseed rape cultivation, and to measure the levels of allergen and other potentially harmful substances released by the crop. METHODS--Random samples of 1000 adults from the general practice populations of two villages surrounded by oilseed rape fields, and 1000 adults from one village far from such cultivation, were taken. The subjects completed a previously validated questionnaire on respiratory and other symptoms, including questions on symptom seasonality, occupation, and smoking habits. Pollen and fungal spore counts were made around fields of oilseed rape and in the villages. The chemicals released by oilseed rape were measured in the field. RESULTS--Overall, 86.8% of the subjects completed the questionnaires and the populations of the two samples were generally comparable. Spring and summer exacerbations of symptoms occurred equally in the two areas in approximately 25% of the population. There were small but significant excesses of cough, wheeze, and headaches in spring in the oilseed rape area (2.3% v 1.1%, 6.8% v 4.6%, and 4.8% v 2.8%, respectively), and cough, wheeze, and itchy skin were more prevalent in smokers. Counts of oilseed rape pollen were generally low except adjacent to fields, and counts of fungal spores were mostly higher in the rape than the non-rape areas. Oilseed rape was shown to give off terpenes and these were detected close to fields. CONCLUSIONS--While it is likely that a proportion of the spring symptoms occurring in people living in close proximity to oilseed rape is caused by the plant, the excess of such symptoms is small. This, together with the low levels of pollen in the area, suggests that allergy to oilseed rape pollen is uncommon. The general prevalence of seasonal symptoms in rural areas is of interest, and a proportion of these cases is likely to be caused by factors other than allergy. Release of chemicals by plants and natural rises in summer ozone levels may be contributors.  相似文献   
9.
Our current knowledge of the biology of Trypanosoma cruzi and its relation to the development of chemotherapy for Chagas' disease are reviewed. This includes recent developments in the understanding of kinetoplast DNA and glycosomes; the action of oxygen radicals; intermediary metabolism of purines, pyrimidines, and folic acid; and the formation of microtubules. At this time, these organelles and metabolic pathways appear to be the most promising for potential exploitation for chemotherapeutic purposes. Compounds of current experimental interest also are discussed. These are agents that have shown promise in the laboratory and for which data exist regarding probable mechanisms of action. The activities of these agents correlated, in so far as is possible, with those structures or metabolic pathways in the trypanonsome that are affected by their actions. The compounds are of two general groups: nitro compounds and purine analogues.  相似文献   
10.
Previous analyses of non-prospectively randomized trials have suggested that early oral postoperative feeding might be a benefit unique to laparoscopic surgery. However, some authors have indicated that early feeding can be tolerated by the majority of patients after elective open surgery. Aim: This prospective randomized study was undertaken to assess whether the time prior to oral intake of food after laparoscopy-assisted surgery is shorter than that after standard laparotomy. Methods: This trial included 40 patients who were divided randomly into two groups before operation. Group I included 20 patients (mean age, 52 years; range , 15 – 77 years) who underwent a laparoscopy-assisted colon or rectal procedure (LAP). Group II consisted of 20 patients (mean age, 56 years, range, 41 – 74 years) who underwent surgery with a standard midline incision (SMI). On the evening after surgery, patients were allowed clear liquids ab libitum. This regimen was continued until the first postoperative day at which time they could elect to start eating a regular diet. If a patient had two episodes of vomiting, a nasogastric tube was inserted. Results: Five laparoscopic procedures were converted to SMI because of adhesions (25%) and an equal number of patients was excluded from the group that was treated in the traditional manner. Therefore, only 30 patients were included in the analysis. There were no deaths in this trial. Complications appeared in four of the patients in the LAP group and in two of the patients in the SMI group (no significant difference). There were no statistically significant differences between the two groups in terms of the ability to tolerate the early oral intake of food, in the frequency of vomiting or in the incidence of insertion of a nasogastric tube. The time to the first bowel movement was 5.4 days in LAP and 5.5 days in SMI, and the difference was not significant. Conclusion: This study invalidates the claim by laparoscopic surgeons that earlier oral intake of food is tolerated by their patients than by patients who undergo standard procedures.
Résumé. Des études randomisées non prospectives ont suggéré que la reprise précoce de l'alimentation orale peut être un bénéfice particulier à la chirurgie laparoscopique. Certains auteurs ont indiqué que la reprise précoce de l'alimentation orale peut être bien tolérée par la plupart des patients après chirurgie élective ouverte. Cette étude prospective randomisée a été entreprise pour déterminer si la reprise orale de l'alimentation après chirurgie laparoscopique peut être plus précoce qu'après une laparotomie standard. Quarante patients ont été inclus dans cette étude et ont été divisés de manière randomisée en deux groupes avant chirurgie. Le groupe 1 comporte 20 patients (15 à 77 ans, moyenne d'age 52 ans) qui ont subi une résection colique ou rectale laparoscopique (LAP). Le groupe II comporte 20 patients (41 à 74 ans, moyenne d'age 56 ans) qui ont subi une chirurgie par une incision médiane standard (SMI). Le soir de l'intervention chirurgicale, les patients ont été autorisés à boire librement. Ce régime a été continué le premier jour postopératoire à partir duquel les patients pouvaient débuter une alimentation normale. Si un patient présente deux épisodes de vomissements, une sonde naso-gastrique a été mise en place. Cinq interventions laparaoscopiques ont d?être converties en chirurgie ouverte en raison d'adhérences (25%) et un nombre égal de patients ont été exclus du groupe qui a été traité de manière traditionelle. En conséquence, 30 patients ont été inclus dans l'analyse. Aucun décès n'est à déplorer. Quatre complications sont survenues chez des patients du groupe laparoscopique et deux dans le collectif des patients ayant subi un chirurgie ouverte (pas de différence statistique significative). Il n'y a pas de différence statistique significative entre les deux groupes en ce qui concerne la tolérance à la reprise orale de l'alimentation, à la fréquence des vomissements ou à la nécessité de réinsérer un tube naso-gastrique. La première exonération est survenue au 5.4 jour dans le groupe laparoscopique et au 5,5 jour dans le groupe de chirurgie ouverte sans que la différence ne soit significative. En conclusion: Cette étude infirme l'idée que la chirurgie laparoscopique permet une reprise précoce et bien tolérée de l'alimentation en comparaison à la chirrugie ouverte.


Accepted: 20 June 1996  相似文献   
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