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991.
Felipe A. Calvo David Ortiz de Urbina Luis Sierrasesúmaga Oscar Abuchaibe Ignacio Azinovic Federico Antillon Manuel Santos Jos Canadell 《Pediatric blood & cancer》1991,19(6):478-485
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.
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
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.
Alternative pathway complement activation induces proinflammatory activity in human proximal tubular epithelial cells 总被引:7,自引:1,他引:6
David S; Biancone L; Caserta C; Bussolati B; Cambi V; Camussi G 《Nephrology, dialysis, transplantation》1997,12(1):51-56
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.
A comparative analysis of radiological and surgical placement of central venous catheters 总被引:3,自引:1,他引:2
Kieran D. McBride Ross Fisher Neil Warnock David A. Winfield Malcolm W. Reed Peter A. Gaines 《Cardiovascular and interventional radiology》1997,20(1):17-22
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.
Marie-Francoise Dresse Michele David Heather Hume Herve Blanchard Pierre Russo Nicolas Van Doesberg Georges E. Rivard 《Pediatric hematology and oncology》1991,8(4):329-334
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.
David W. Smith 《Statistics in medicine》1994,13(10):1001-1013
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