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991.
From September 1984 to December 1989, 38 patients of pediatric age with localized bone sarcomas received intraoperative radiotherapy (IORT) as part of a multidisci plinary treatment program. The age ranged from 6 to 21 years. The tumor histologies were 22 osteosarcomas and 16 Ewing's sarcomas. Thirty-four had initial primary disease (90%) and 4 were treated for local recurrence (10%). IORT was used on 32 untreated patients and in 6 previously treated with external beam radiotherapy (EBR). The IORT field included the surgically exposed tumor bed area. Single radiation doses ranging from 10 to 20 Gy were delivered, using 6–20 MeV electron beams. The median follow-up time for the entire group is 25 months (2–65+ months). The projected 5-year disease-free and overall survival rates are 65% and 69%, respectively. One patient developed a local recurrence in each histological group: one chondroblastic osteosarcoma and one cervical Ewing's sarcoma. Six patients died from metastatic progression: 3 initially recurrent tumors and three primary disease cases. Severe neuropathy and soft tissue necrosis were seen in some patients as IORT related complications. IORT is a feasible technique to be integrated in multidisciplinary programs that may promote local control in pediatric and adolescent patients with bone sarcomas. Peripheral nerves are dose-limiting tissue structures for IORT.  相似文献   
992.
993.
HemorrhagicfeverwithrenalsyndromevirusinfectioninliversstudiedbyinsituhybridizationandimmunohistochemistryYangShoujing(杨守京);L...  相似文献   
994.
995.
Abstracts     
Chronic Cough Irwin, Curley, and French: Am Rev Respir Dis 141: 640-647, 1990

The Interrelationship Among Bronchial Hyperresponsiveness, the Diagnosis of Asthma, and Asthma Symptoms Pattemore PK, Asher MI, Harrison AC, Mitchell EA, Rea HH, Stewart AW: Am Rev Respir Dis 142: 549-554, 1990

Inhaled Albuterol and Oral Prednisone Therapy in Hospitalized Adult Asthmatics: Does Aminophylline Add Any Benefit? Self TH, Abou-Shala N, Burns R et al: Chest 98:1317, 1990

Formoterol in the Treatment of Nocturnal Asthma Maesen FPV, Smeets JJ, Gubbelmans HLL, Zweers PGMA: Chest 98: 866, 1990  相似文献   
996.
Background. Proximal tubular epithelial cells express a surface C3-convertase activity which induces C fixation and insertion of the C5b-9 membrane attack complex (MAC) into the cell plasma membrane. The physiopathological consequences of this phenomenon are unknown. Methods. The effect of C fixation on the production of inflammatory mediators by human proximal tubular epithelial cells in culture was explored. Results. Proximal tubular epithelial cells incubated with a sublytic amount of normal human serum as a source of C, but not with heat-inactivated human serum, showed a time-dependent calcium influx and a concomitant release of 14C-arachidonic acid (14C-AA). Eicosanoid synthesis following the arachidonic acid mobilization was studied as prostaglandin E2 release. Mg2+/EGTA, which did not prevent C activation by the C3-convertase, and p-bromodiphenacyl bromide, a phospholipase A2-inhibitor, inhibited mobilization of 14C-AA. These results suggest the activation of an extracellular Ca2+-dependent, phospholipase A2. Complement fixation was associated with the synthesis of proinflammaotry cytokines such as IL-6 and TNF-&agr;. Experiments with C6-deficient sera indicated that the release of 14C-AA and the production of cytokines were dependent on the insertion of the terminal components of complement in the plasma membrane. Indeed, the reconstitution of normal haemolytic activity of C6-deficient sera with purified C6 restored also the release of 14C-AA and the production of cytokines. Conclusion. In vitro complement activation on the proximal tubular cell surface triggers the generation of proinflammatory mediators, which may potentially contribute to the pathogenesis of tubulointerstitial injury.  相似文献   
997.
Purpose To compare the differences in practice and outcome of all radiologically and surgically placed central venous catheters retrospectively over a 2-year period simultaneously, at a single institution. Methods A total of 253 Hickman catheters were inserted in 209 patients; 120 were placed radiologically in 102 patients and 133 were placed surgically in 107 patients. The indication was chemotherapy in 76% of radiological and in 47% of surgical cases; the remainder were for total parenteral nutrition and venous access. Results There were 6 (4.5%) primary surgical failures and a further 17 (13%) surgical cases requiring multiple placement attempts. Pneumothorax occurred once (0.8%) surgically and four times (3.3%) radiologically. There were no radiological primary misplacements but there were five (3.7%) surgical ones. Catheter or central vein thrombosis occurred in four (3.3%) radiological and five (3.7%) surgical cases. The rate of infection per 1000 catheter-days was 1.9 in radiologically placed catheters and 4.0 in surgically placed ones (p<0.001). Average catheter life-span was similar for the two placement methods (100±23 days). Conclusion Radiological placement is consistently more reliable than surgical placement. There are fewer placement complications and fewer catheter infections overall.  相似文献   
998.
目的 :观察氯沙坦对行维持性血透治疗的慢性肾功能衰竭 (CRF)患者心血管保护作用。方法 :6 0例维持性血透患者 (血肌酐≥ 70 0 μmol·L- 1 ) ,治疗组 (给予氯沙坦 5 0~ 10 0mg·d- 1 )及对照组 (给予非血管紧张素受体拮抗剂和非ACEI类降压药 )各 30例 ,记录用药前后各组患者血压 ,运用多普勒组织成像 (DTI)技术观察用药前后两组患者二尖瓣环峰值收缩速度 (VS)、收缩时间速度积分 (TVIS)、舒张早期速度 (VE)、舒张晚期速度 (VA)、VE VA 比值。结果 :治疗组及对照组患者治疗后血压均明显下降 ,二尖瓣环VS、TVIS、VE、VE VA ,则均明显上升 ;治疗组与对照组血压分别在治疗前、后相比并无明显差异 ;治疗前两组间二尖瓣环VS、TVIS、VE、VE VA 并无显著性差异 ,但在治疗12个月后 ,治疗组二尖瓣环VS、TVIS、VE、VE VA 则明显高于对照组。结论 :氯沙坦对行持续性血透的CRF患者具有良好的心脏保护作用 ,可有效改善其心功能 ,且不依赖于其降压作用  相似文献   
999.
The Kasabach-Merritt syndrome is characterized by thrombocytopenia and localized coagulopathy associated with a hemangioma. Most techniques applied to eradicate the tumor or accelerate its involution (surgery, radiation therapy, embolization) are invasive and require transfusion of large amounts of blood products. In some cases, medical treatment is the only alternative. Efficacy of steroids and antifibronolytic agents has already been described, but even this approach is associated with the administration of blood products. We report two cases of infants with Kasabach-Merritt syndrome associated with cardiac and hepatic hemangiomas. At admission, both had signs of cardiac failure. They were successfully treated with prednisone and epsilon-aminocaproic acid (EACA). Blood products were not required once the diagnosis was made. These observations have important implications for the management of patients with Kasabach-Merritt syndrome because they show that even in severe cases blood transfusions can be avoided by the use of prednisone and EACA.  相似文献   
1000.
The variation in mortality rates among hospitals has often been described informally as having three major components: patient severity, quality of care and random variation. These informal concepts are characterized formally by partitioning sums of squares and finding their expected values. The partition relates to commonly used tests for whether individual hospitals have unusual mortality rates. Application of the partition to the hospital mortality reports by the Health Care Financing Administration shows that their models for patient risk account for about one-half the variation among hospital mortality rates. An example using clinical measures of severity accounts for about two-thirds of mortality variation among hospitals.  相似文献   
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