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91.
PURPOSE: To analyze visual and anatomic results following surgical repair of cytomegalovirus (CMV)-related retinal detachment (RD) without silicone oil permanent tamponade. METHODS: We analyzed five consecutive patients (six eyes) with acquired immunodeficiency syndrome and CMV-related RD that were repaired with pars plana vitrectomy with peeling of the posterior hyaloid, laser photocoagulation, encircling scleral buckle, and intraocular gas tamponade. RESULTS: Preoperative vision ranged from 20/40 to hand motion. Total retinal reattachment was achieved in five of six eyes (83%). Macular reattachment was achieved in all eyes. Mean postoperative visual acuity was 20/40 (range 20/30-20/60). Mean postoperative follow-up was 12 months (range 7-19 months). All patients in this series presented with low preoperative CD4+ T-lymphocyte counts (mean, 24 cells per microL) and received highly active antiretroviral therapy. One retina (Patient 1) redetached 7 months after initial repair and was successfully reattached without using silicone oil. Postoperatively, visual acuity remains 20/30, and total retinal reattachment has been maintained for 16 months. CONCLUSION: Good anatomic and visual success can be achieved and maintained in CMV-related RD without the use of silicone oil.  相似文献   
92.
Fat emulsions can cause changes in blood-clotting and fibrinolysis. The aim of this study was to examine the relation between the use of the short-acting hypnotic propofol and alteration of the blood clotting system. In a double-blind randomized study, 36 patients with an aortocoronary bypass operation were given either midazolam/fentanyl or propofol/alfentanil. Eleven blood samples were taken at fixed times pre-, intra- and postoperatively to determine changes caused by the anesthetic agents on the hemostaseologic parameters during the whole operation. Perioperative blood pressures of both groups were measured at seven fixed points. From the beginning of the extracorporeal circulation (ECC) to the end of the operation, the measured values of the factor XIIa- and kallikrein-like activity in the propofol group were significantly higher than those of the midazolam group. Also the values of the kallikrein inhibition capacity and the indicators of fibrinolysis (t-PA and D-dimers) suggest a stronger activation of the contact phase at the start of the recirculation and as a result of it a stronger fibrinolysis within the propofol group. Besides, the hypotensive side-effect in the propofol group was evident in contrast to the midazolam group. With this investigation, a correlation between the application of propofol/alfentanil, contact phase activation with activation of the kallikrein-kinin-bradykinin system and the observed hypotension can be set up.  相似文献   
93.
During the past 10 years investigations have demonstrated that heparin-coated devices used for extracorporeal circuits show an improved hemocompatibility. We investigated the pathway of adsorption of plasma proteins at heparin-coated artificial surfaces and the further activation of the humoral and cellular defense mechanisms of the blood. Twenty milliliters of fresh human blood (1 IU heparin/ml) filled a 50 cm long tubes (with and without covalent heparin-coating), prepared as an in vitro "Closed-Loop" model and recirculated at a temperature of 37 degrees C. After 5, 15, 30, 60 and 120 min fibrinogen and high molecular weight kininogen (HMWK) adsorption was measured by a newly developed modified ELISA technique. In addition, changes in coagulation and platelet activation were measured by well established assays. High concentrations of fibrinogen were detected after very short blood material contact, both on uncoated as well as heparin-coated tubes. However, high amounts of HMWK were only found on the heparin-bonded surfaces. In addition, the concentrations of the soluble coagulation marker prothrombin fragment F1+2 and the marker for platelet activation beta-thromboglobulin were significantly higher in the non-coated tubes. We presume that adsorption of HMWK to heparin-coated surfaces contributes to the improved hemocompatibility of these bondings.  相似文献   
94.
95.
A patient with downbeat nystagmus subsequent to ankylosing spondylitis was studied. His nystagmus was found to exhibit both increasing- and decreasing-velocity exponential slow phases as well as the linear form more often reported. Alternation between waveforms sometimes occurred on a beat-to-beat or even intrabeat basis. Possible explanations for all three waveforms are presented in terms of short-term gain changes in cerebellar compensation for leaky brainstem neural integrators. A computer model was developed and its results are discussed.  相似文献   
96.
We report on the acute poisoning of a 5-year-old boy by the herbicide "dichlorprop". This preparation is described as an effective means of plant protection. The effects of the intoxication were established by changes observed in almost all of the child's organs. The predominant effect was haemolytic anemia. All the pathological parameters regressed as a result of symptomatic therapy. General conclusions are drawn about intoxication, especially by means of plant protection agents.  相似文献   
97.
98.
Over the past decade, prostate brachytherapy has been increasingly utilized as definitive management for early stage carcinoma of the prostate gland. One risk of the procedure is pulmonary seed embolization. In this article we report the incidence and timing of seed migration. Pulmonary embolization of radioactive seeds occurs in approximately 20% of patients undergoing prostate brachytherapy. To date, no acute or delayed detrimental effects have been reported which are attributable to the pulmonary embolization of the seeds; nevertheless, it is imperative that patients and health care providers be cognizant of this possible event.  相似文献   
99.
Molecular and cellular biology of prostate cancer   总被引:7,自引:0,他引:7  
Prostate cancer is an enigmatic disease. Although prostatic-intraepithelial neoplasia appears as early as the third decade and as many as 80% of 80 year old men have epithelial cells in their prostate that fit the morphological criteria for cancer, only about 10% of men will ever have the clinical disease and less than 3% will die from it. There have been no significant proven interventions which have altered the natural history of the disease since hormone down regulation was introduced in the 1940s and new research has been poorly supported. There is however an urgent need to develop new criteria to distinguish those patients with localised disease who will benefit from intervention from those that do not require it or who will have occult extra prostatic metastases. Similarly, there is an urgent need to develop new treatment for those in whom the disease is extra-prostatic and therefore incurable by conventional treatments. This review covers the latest developments in epidemiology, cellular and molecular biology including new areas such as ion channels in the field of prostate cancer.  相似文献   
100.
Objective: Our purpose was to determine the incidence of gestational diabetes mellitus in an adolescent population and to determine the cost of screening. Study Design: A retrospective review of 509 adolescent pregnancies was performed. The incidence of gestational diabetes mellitus was determined and the cost of screening analyzed. Results: Five hundred nine adolescent pregnancies were screened for gestational diabetes mellitus with a 1-hour, 50 gm oral glucose challenge test. Twenty-three of the screens (4.5%) had positive results at a plasma glucose level of ≥140 mg/dl. Three-hour 100 gm oral glucose tolerance tests were performed on screen-positive women, six of whom were diagnosed with gestational diabetes mellitus, for an incidence of 1.18%. The cost per case diagnosed was $2733. Conclusions: The incidence of gestational diabetes mellitus in an adolescent population is low. The cost of universal screening may be prohibitive in this population. Large prospective studies are needed to better analyze outcome data and efficacy of screening in adolescent pregnancies. (Am J Obstet Gynecol 1998;178:1251-6.)  相似文献   
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