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991.
992.
BACKGROUND: [corrected] A National Institutes of Health-funded clinical trial of patients undergoing coronary artery bypass randomized perfusate and myocardial preservation to cold, tepid, or warm temperatures. The goal of the trial was to evaluate neurologic function before and after operation (4 days and 1 month after operation) and to measure hematologic data for fibrinolytic potential. METHODS: The three groups comprised 116 patients who completed neurologic evaluation by means of the Mathew scale out of 130 entered into the trial (37 cold group, 50 tepid, and 43 warm). Twenty-five patients had complete hematologic studies done. All three groups were comparable before operation. The myocardial preservation protocol used blood cardioplegic solution at cold (8 degrees to 10 degrees C), tepid (32 degrees C), or warm (37 degrees C) temperature and the systemic perfusate temperature during cardiopulmonary bypass was 20 degrees (cold), 32 degrees C (tepid), or 37 degrees (warm). RESULTS: Patients in the cold group had a longer duration of intubation and postoperative hospitalization and a slightly but significantly higher peak postoperative creatine kinase MB level than patients in the warm group. There were no deaths. There was deterioration in Mathew scale findings in all three groups, and no distinction could be made between groups. However, a significantly higher number in the cold group had an abnormal postoperative neurologic examination result that prompted computed tomographic scanning (18.9% cold, 2% tepid, 9.3% warm). A cerebrovascular accident was documented by computed tomographic scanning in 8.1%, 0%, and 4.7% of patients in the cold, tepid, and warm groups, respectively (not significant). Hematologic data documented significantly increased fibrinolytic potential in the warm group. CONCLUSIONS: Perfusion temperature is a factor in recovery from cardiopulmonary bypass. Cold has more adverse neurologic sequelae that prompt computed tomographic scanning whereas warm has more activation of fibrinolytic potential. Tepid is the best temperature for optimizing recovery from cardiopulmonary bypass.  相似文献   
993.
This report describes an 11-year-old male who presented to his pediatrician at the Bowman Gray School of Medicine in Winston-Salem, N.C., because of long standing enuresis. During evaluation and the following two-week period, this patient was found to have extreme thrombocytosis ranging from 2,175 x 10(9)/L to 3,700 x 10(9)/L. In the absence of any apparent reactive cause, a presumptive diagnosis of essential thrombocythemia was made. Although chemotherapy was considered, the patient was temporarily lost to follow-up before there was a final decision about therapy. One year later, this patient's platelet count had spontaneously decreased to normal (273 x 10(9)/L), and has remained normal during a follow-up period of seven years, although only sporadic platelet counts have been obtained. His most recent physical examination revealed no abnormalities. The case is presented as further evidence that extremely high platelet counts are not necessarily dangerous and do not all require therapy.  相似文献   
994.
995.
Women who received Norplant contraceptive implants from any of fifteen clinical settings in southeast Texas, U.S.A., were followed for one year to determine their reactions to the method. Of 1,385 who enrolled to receive Norplant implants, 1,253 had implants inserted. Side effects were reported by 78% of those receiving implants and 70% described changes in bleeding patterns. Spotting or irregular bleeding, weight gain and headaches were the conditions reported most frequently. Nine pregnancies were reported during the study period. Six of these, however, existed before the implants were inserted. At the one year anniversary, 143 of women receiving implants had had them removed. Those who discontinued method use were less satisfied, reported more side effects and were more likely to have planned to have another child, thus using the method for spacing, or to have had a change in their marital status while they were using the contraceptive. Providers should counsel patients to focus attention on plans for the future in selecting their contraceptive method. In addition, we recommend, as does the product's distributor, that providers confirm that patients are not pregnant prior to inserting implants.  相似文献   
996.
997.
The classic appearance of porokeratosis is characterized by a hyperkeratotic annular rim that expands peripherally, leaving an atrophic center. Linear porokeratosis is a variant with collections of such lesions arranged in a linear fashion, usually corresponding to a dermatome or Blaschko's lines. Ulcerations have rarely been reported in patients with porokeratosis. We report an unusual case of linear porokeratosis at birth, with erosions and ulcerations of the face and lower extremity, that eluded diagnosis for nearly a year. Porokeratosis should be considered in the differential diagnosis of erosions in the newborn period.  相似文献   
998.
999.
Red blood cell lysis and histidine degradation, photosensitized by tiaprofenic acid (TIA), were investigated. Photohaemolysis was markedly enhanced in oxygenated solutions, but was also intense in the presence of nitrogen. Photohaemolysis was inhibited by butylated hydroxyanisole and reduced glutathione, but was unaffected by sodium azide, superoxide dismutase and mannitol. The TIA-induced photo-oxidation of histidine was greatly enhanced in the presence of oxygen and almost completely inhibited in solutions bubbled with nitrogen. Sodium azide, butylated hydroxyanisole and reduced glutathione inhibited the photodegradation of histidine. Phototoxicity to histidine was unaffected by mannitol and superoxide dismutase. The overall results suggest that molecular mechanisms involving free radicals and singlet oxygen are responsible for TIA-photosensitized reactions. These two in vitro models (photohaemolysis and histidine degradation) represent different mechanisms of phototoxicity, but complement one another in the investigation of potential phototoxic substances.  相似文献   
1000.
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