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991.
This report describes a 4-month-old infant with multisystem organ failure who developed severe hypernatremia (sodium 168 mEq/l) due to rapid free water removal associated with acute peritoneal dialysis instituted for fluid overload. The current report describes the pathophysiology of the hypernatremia, and its correction by low-sodium hypertonic peritoneal dialysis without compromising ultrafiltration or supplementing with free water. Although peritoneal dialysis can cause hypernatremia, a modified solute concentration in the dialysate can treat the hypernatremia successfully. Received: 2 January 2001 / Revised: 24 April 2001 / Accepted: 24 April 2001  相似文献   
992.
993.
Although there have been experimental approaches to understanding the etiology of Parkinson's disease, the cause of cell degeneration in this neurological disorder remains a mystery. Herein, a hypothetical model is proposed to explain the mechanism leading neurons to die. The model is based on recent experimental evidence and it attempts to dissect the actions of dopamine and metal ions as potential triggers for the activation of an ordered cascade of events of the cell death machinery.  相似文献   
994.
The emergence of a sizable Hispanic population in the US is a relatively recent historical phenomenon, and thus much is still unknown about this group of North Americans. Data from national surveys suggest small differences between Hispanic and non-Hispanic white populations in the age-adjusted prevalence of self-reported arthritic conditions. However, the rate of activity-limitation attributable to arthritis is higher among Hispanic patients. This likely reflects the poorer socioeconomic conditions and lack of health insurance that prevail among Hispanic populations, which may limit their access to rheumatologic care. Osteoporotic vertebral and hip fractures are less frequent, and proximal femoral mineral density is higher, in Hispanic individuals than in non-Hispanic white individuals. The mechanisms for these observations are currently under investigation. There have been no studies of the prevalence of osteoarthritis, rheumatoid arthritis, or systemic lupus erythematosus among Hispanic populations. However, important immunogenetic, clinical, and psychosocial differences between Hispanic and non-Hispanic patients in regard to rheumatoid arthritis and systemic lupus erythematosus have been reported. There is no published information on the prevalence or characteristics of other rheumatic diseases in the US Hispanic population. Emerging evidence suggests considerable underuse of certain health services for arthritis among Hispanic patients, likely due in part to socioeconomic factors. Further research is needed to determine whether biologic, cultural or psychosocial factors contribute to underuse as well. There is clearly a need for data on the prevalence and characteristics of arthritis and other rheumatic and musculoskeletal diseases in this emerging US population.  相似文献   
995.
Protective effect of melatonin against adriamycin toxicity in the rat   总被引:1,自引:0,他引:1  
Adriamycin, an anthracyclinic antibiotic frequently used in quimioterapeutic treatments is highly toxic; it inhibits protein synthesis and provokes prooxidant effects. Melatonin has recently been shown to have high antioxidative properties. We tested if melatonin is able to neutralize the oxidative damage induced by a single dose (20 mg/kg, i.p.) of adriamycin preceded (3 days) and followed (7 days) by a low pharmacological dose (50 microg/kg, i.p.) of melatonin. After the administration of a single dose of adriamycin (20 mg/kg i.p.) to male Wistar rats, the reduced to oxidized glutathione (GSH/GSSG) ratio and the glutathione peroxidase (GPx, E.C. 1.11.1.9.) activity in the brain, intestine, heart, kidney, and lung were significantly reduced. When the treatment of adriamycin was preceded and followed by low pharmacological doses of melatonin, the decrease in the GSH/GSSG ratio was significantly reduced but the reduction in GPx activity was not attenuated. A significant increase in lipid peroxidation products was observed in brain, heart, and kidney tissues after a single administration of adriamycin, which was attenuated by pre- and post-treatment with a low pharmacological dose of melatonin. Our results demonstrate that oxidative damage induced by the antitumor drug, adriamycin, can be reduced by low pharmacological doses of melatonin.  相似文献   
996.
997.
Organ preservation has been investigated in muscle-invasive bladder cancer over the past decades as an alternative to standard radical cystectomy. The results of large prospective protocols and population-based studies suggest that an organ-preserving approach is possible without deferring the survival probability. Organ preservation requires a trimodal schedule, including transurethral surgery (transurethral resection of bladder tumor (TURBT)), radiation, and chemotherapy. A complete TURBT is the most important single prognostic factor, and should be attempted. Radiotherapy, in conjunction with concurrent platinum-based chemotherapy, can control the vast majority of urothelial bladder tumors. The histologically-proven complete remission rates of macroscopic tumors (unresectable by TURBT) lie in the range of about 70%. After radiochemotherapy, a histological response evaluation with repeated TURBT is recommended. Patients with residual tumor require salvage cystectomy. In cases of complete remission, patients can maintain their bladders but they should be closely followed over years. The risk of severe late-radiation sequelae is low, in the range of less than 5%. About 75% of long-term survivors maintain a normally functioning bladder.  相似文献   
998.
Combined modality treatment is the recommended standard adjuvant therapy for patients with locally advanced rectal cancer in the United States and Germany. During the last decade substantial progress has been made in treatment modalities, and surgical management currently includes a broad spectrum of operative procedures ranging from radical operations to innovative sphincter-preserving techniques. Specialized groups have reported excellent local control rates with total mesorectal excision (TME) alone. New and improved radiation techniques (conformal and intraoperative radiotherapy) and innovative schedules (protracted intravenous and chronomodulated infusion) and combinations (oxaliplatin and irinotecan) of chemotherapy may have the potential to further increase the therapeutic benefit of adjuvant treatment. Moreover, the basic issue of timing (pre- or postoperative) within a multimodal regimen is currently being addressed in prospective trials. Evidently there is a need to question the current monolithic approaches, which were established by studies conducted more than a decade ago. It is also under discussion whether to apply the same schedule of postoperative radiochemotherapy to all patients with stage II/III rectal cancer, or to give preoperative intensive short-course radiation according to the Swedish concept for all patients with resectable rectal cancer irrespective of tumor stage and treatment goal (e.g., sphincter preservation). This review discusses different irradiation settings in more recent and ongoing studies of perioperative radiotherapy for rectal cancer, and focuses on the issue of which patient should receive radiotherapy (if at all), and if so, how and when.  相似文献   
999.
1000.
The difference with which the pre-lingual and post-lingual profoundly deaf confront their deafness is evident: the reticence of many pre-lingual deaf persons when faced with technological advances and genetic investigations is not present among the post-lingual deaf. This article looks at this difference from the person as a whole, and aims to carry out a comparative study of the personalities of both groups and of the non-deaf. To this end, three samples were taken (one of pre-lingual deaf persons, one of post-lingual deaf persons and a third of non-deaf persons) and the Mini-Mult personality questionnaire was employed as a measuring instrument. Significant differences were found in 5 clinical scales: Hs (hypochondria), Hy (hysteria), Pa (paranoia), Pt (psychastenia), Sc (schizophrenia). The differences between the deaf and the non-deaf are statistically significant. The profile obtained for the pre-lingual deaf is high on the schizophrenia scale (Sc), and suggests a kind of person where the said scale might detect isolation derived from deafness. The profile of the post-lingual deaf, marked by the hypochondria scale, shows persons with severe hypersensibility and fears regarding their state of health. The significant influence of variables such as level of education and state of employment on the post-lingual deaf and, in particular, on his feeling of loneliness and his worries regarding his deafness, his state of mind and his possible paranoiac tendencies, makes them factors that must be taken into consideration when fundamentally evaluating the personality of a post-lingual deaf person. These personality traits influence the way a profoundly deaf person confronts his deafness.  相似文献   
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