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71.
L-asparaginase, an effective antileukemia and antilymphoma agent, is toxic to many organ systems. We report a case of ureteral obstruction caused by L-asparaginase via the inflammatory complication of acute pancreatitis. The patient was an 11-year-old boy with acute lymphoblastic leukemia. Six days after completing a 4-week induction therapy containing 9 doses of L-asparaginase, severe left abdominal pain developed. Abdominal computed tomography showed phlegmon formation anterior to the pancreatic head and in the left posterior pararenal space. The strands of inflammatory soft tissues encased the upper third of the left ureter, causing left hydroureter and left hydronephrosis. The ureteral obstruction resolved after insertion of a double-J catheter that remained in place for 66 days. This case suggests that L-asparaginase may play a role in the pathogenesis of ureteral obstruction in children receiving chemotherapy.  相似文献   
72.
Submitral ventricular aneurysm is a thoroughly studied pathology but is not well known due to its rarity. Clinically, it is manifested by symptoms and signs of heart failure, mitral regurgitation and/or ventricular arrhythmias, and may be associated with thromboembolic phenomena and myocardial ischemia due to compression of the coronary arteries by the aneurysm. A rare complication of this type of aneurysm is rupture into the left atrium. Transthoracic echocardiography plays an important role in the definitive diagnosis of this pathology, although the role of transesophageal echocardiography in the evaluation of these patients is less known. We report a case of a submitral ventricular aneurysm complicated by rupture into the left atrium, which was diagnosed by transesophageal echocardiography.  相似文献   
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74.
This study investigated a discrete-trial, titration duration discrimination procedure in behavioral pharmacology. Pentobarbital and d-amphetamine, measured with this procedure, selectively affected discrimination more than response tendencies. Pentobarbital also tended to affect selectively discrimination of longer durations, whereas d-amphetamine did not. Further experiments showed that (1) other algorithms for modulating stimulus duration are useful in behavioral pharmacology and toxicology, (2) threshold estimates are similar with the method of constant stimuli and the method of titration, and (3) this titration procedure permits the separate examination of drug effects upon discrimination and upon response tendencies; the fixed-interval procedure does not. Baseline variability was an important correlate of drug effects in that the endpoints with more variable baselines were also more sensitive to drugs.  相似文献   
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76.
This study examined the mitogenic response to keratinocyte growth factor (KGF) of normal and tumour-derived human oral keratinocytes in which the degree of cellular differentiation was known and in contiguous fibroblast cultures derived from the malignant epithelial cultures. Keratinocytes, but not fibroblasts, were stimulated by KGF. There by demonstrating epithelial target cell specificity of the ligand. KGF-induced stimulation of the tumour-derived keratinocytes cultured in the absence of the 3T3 fibroblast support broadly correlated with the degree of cellular differentiation; well-differentiated keratinocytes were stimulated more by KGF than their less differentiated counterparts. Malignant oral keratinocytes expressed KGF cell surface receptors (KD 451-709 pM; receptors/cell 2306-413645), but KGF receptor mRNA did not correlate with either KGF-induced mitogenesis or the degree of epithelial cell differentiation. When the tumour-derived keratinocytes were cultured in the presence of 3T3 fibroblasts, the mitogenic response to KGF was comparable to normal epithelial cells. The results suggest that KGF-mediated growth stimulation may not be significant in providing a selective advantage for the growth of malignant keratinocytes.  相似文献   
77.
In order to determine whether a specialist psychogeriatric nursing home was fulfilling its intended role of caring for the most behaviourally disturbed dementia sufferers, 24 of its demented residents were compared with 28 demented individuals discharged from a psychiatric unit to ordinary nursing homes and 30 mobile dementia sufferers in nursing home wards of a geriatric centre. Those in the psychogeriatric nursing home showed more disturbed behaviours than those in the other two settings. Scores on the Rating Scale for Aggressive Behaviour in the Elderly were compared with degree of cognitive impairment for the first time in the literature and showed no correlation with degree of cognitive impairment for the first time in the literature and showed no correlation with congnitive performance.  相似文献   
78.
Background : A retrospective analysis of 103 case records from 1978 to 1996 with a provisional diagnosis of Buerger's disease was undertaken at the Department of Surgery, University of Hong Kong, Queen Mary Hospital. The aim of the study was to elucidate the clinical course and evaluate the results of surgical intervention of Buerger's disease in Hong Kong Chinese people. Methods : Fourteen patients were subsequently excluded from the study because of inability to fulfil our diagnostic criteria. Data on clinical presentation, investigations, indications and results of surgical intervention were reviewed. Sympathectomies and arterial reconstructions were performed on 42 and four patients, respectively, for critical ischaemia or rest pain. Outcome was analysed with respect to the rate of ulcer healing, pattern of recurrence and limb loss. Results : The patients were all young male heavy smokers with a mean age of 36.5 years. The majority of patients (80%) presented with ischaemic ulceration or gangrene. Vascular reconstruction was undertaken in four patients and satisfactory long-term results were obtained in three patients. Sympathectomy was able to relieve symptoms in 87% of operated patients and ischaemic ulceration healed in 2.6 (mean) ± 1.7 (SD) months after the operation. If the patient continued to smoke, surgical intervention did not exempt the patient from a relapse or amputation. Conclusion : Sympathectomy provides short-term pain relief and promotes ulcer healing in patients with Buerger's disease but carries no long-term benefit. Complete abstinence from smoking is the only means of arresting the progression of the disease.  相似文献   
79.
白细胞介素—2新的功能位点及其中枢镇痛作用   总被引:2,自引:0,他引:2  
白细胞介素-2(IL-2)不仅是重要的免疫调节因子,而且还具有重要的中枢调节作用。本实验以钾离子透入引起大鼠甩尾反应为指标,发现侧脑室注射IL—2能显著提高动物痛阈,并能被纳洛酮所阻断,表示IL-2的中枢镇痛作用可能与阿片受体有关。利用基因定位突变技术获得的无免疫活性IL-2实查体仍具有中枢镇痛作用,表明IL—2分子上发挥镇痛和免疫调节作用的功能位点是相互独立的。纳洛酮能够阻断IL—2的中枢镇痛作用,而不能影响IL—2增殖CTLL-2细胞的作用,提示IL-2发挥镇痛和免疫调节作用可能通过不同的受体途径。IL-2分子中第45位Tyr残基突变为Val后,虽仍保留了免疫活性,但丧失了镇痛功能,表示45位Tyr残基是IL—2发挥中枢镇痛功能的关键残基之一。我们推测IL—2的镇痛功能位点可能在IL—2分子中第45位Tyr残基附近区域。  相似文献   
80.
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