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51.
Summary: The present study was undertaken in the hope that conflicting opinions concerning interrelationships among minimal change disease (MCD), mesangial proliferative glomerulonephritis (MPG) and focal segmental glomeruloscierosis (FSGS) might be elucidated by morphometric methods performed by image analysis, as well as to study whether serum creatinine and changes in quantitatively analysed glomeruli could correlate with the interstitial fibrosis in these glomerulopathies. Fifteen renal biopsy specimens from children with MCD, 10 with primary MPG and 12 with FSGS for whom both light and electron microscopy as well as immunofluorescence microscopy and full clinical data were available, were examined quantitatively. As a control five biopsy and 10 autopsy specimens of the normal kidneys were used. Our quantitative study showed that in MCD, MPG and FSGS glomerular and interstitial values differed from normal. Morphometric differences between MPG and both MCD and FSGS groups were also shown. Although the mean values of total glomerular area and relative interstitial volume were increased in FSGS patients, in total glomerular cells per unit of glomerular area and mesangium (% of total glomerular area) were similar in both MCD and FSGS groups. In MPG strong positive correlations existed between interstitial volume and serum creatinine, interstitial volume and total glomerular cells per unit of glomerular area as well as between interstitial volume and glomerular mesangium (% of total glomerular area). In FSGS there was significant positive correlation between interstitial volume and serum creatinine. In the MCD group all correlations were weak and not significant. In conclusion, our morphometric studies suggest a close relationship between MCD and FSGS, and indicate that MPG is a separate morphologic entity in children.  相似文献   
52.
The objectives of this study was to assess the overall effect of N-acetylcysteine (NAC) in preventing radiocontrast-induced nephropathy (RCIN) using all available data in the literature. RCIN is associated with increased morbidity and mortality. Existing randomized trials of NAC are small and show inconsistent results. Prior meta-analyses do not include data from the most current studies. We used standard search protocols to identify all published articles and abstracts of prospective trials using NAC with fluid hydration compared to hydration alone in patients with chronic renal insufficiency undergoing contrast procedures. A rise in serum creatinine by 0.5 mg/dl or 25% above baseline at 48-72 hr after contrast exposure was used as the primary outcome. We identified 14 trials of NAC with 1,584 patients published as full-text articles. Using a random-effects model, the use of oral NAC resulted in a significant reduction in the risk for developing RCIN (RR = 0.57; 95% CI = 0.37-0.84; P = 0.01). This finding did not significantly change in a fixed-effect model (RR = 0.55; 95% CI = 0.42-0.73) or when the data were reanalyzed using only randomized trials in all forms (i.e., articles and abstracts; RR = 0.67; 95% CI = 0.47-0.95). We identified only one important difference between the positive and the negative studies: the cumulative exposure to contrast media (174 vs. 152 ml). Metaregression did not show a significant relationship between contrast volume and the RR of developing RCIN (P > 0.10). In the trials showing benefit for NAC, the treated patients' postprocedure creatinine unexpectedly decreased by 0.21 mg/dl (95% CI = 0.33-0.08). Prophylaxis with NAC significantly reduces the risk for RCIN. The reasons for improvement in serum creatinine in patients treated with NAC are unclear, but may include improved renal blood flow due to NAC and/or vigorous hydration.  相似文献   
53.
54.
Geographical variations in the incidence of disease are of considerable theoretical and practical importance. It has been claimed that the distribution of acute lymphoblastic leukemia (ALL) phenotypes in Saudi Arabia is different from that recorded in the Western literature. One hundred and twelve (112) patients under 15 years of age, diagnosed as ALL between January 1992 and May 1994 had immunophenotypes performed on their blast cells. Common ALL (cALL) together with pre-B-ALL, formed 86.5% of the total; B-cell 3%, T-cell 6% and null cell 4.5%. These figures are not significantly different from the Western literature. A previous claim from this institution in 1990, that both null and B-cell ALL were significantly increased compared with elsewhere, is not supported by the present figures. Age and sex distribution, and FAB classification, L1 77%, L2 20% and L3 3%, were also of the same order as described elsewhere and, in particular, there was no increase in the frequency of L3 subtype.  相似文献   
55.
To determine if dexamethasone has a role in the treatment of meningeal leukemia, 8 consecutive patients with acute lymphoblastic and signs or symptoms of CNS were included in the study. After the confirmation of leukemic blast cells on cerebrospinal fluid, they received intrathecal and IV dexamethasone; 3 days later the patients received “triple” intrathecal chemotherapy with dexamethasone, methotrexate and cytarabine, and the spinal fluid was studied again. All patients had good clinical response and 7 out of the 8 patients showed reduction on the CSF cell count after the use of dexamethasone alone. The results suggest that dexamethasone is a lympholytic agent that could play a more active role in the prevention and therapy of meningeal leukemia and should be preferred over hydrocortisone in the so called “triple” intrathecal chemotherapy for the prevention and treatment of CNS leukemia. © 1995 Wiley-Liss, Inc.  相似文献   
56.
Renal gene transfer techniques are being developed as a novelexperimental approach to understand the pathogenesis of renaldisease and to potentially develop new therapeutic tools. Wereview the currently available technology to introduce foreigngenetic material into renal tissue, i.e., retroviral, adenoviral,and liposomal transfer systems with their respective advantagesand caveats. Today, the transfer efficiency of these methodsappears to be sufficiently high to study the effects of transducedgenes on renal function and morphology in rat kidney. This willallow (i) the elucidation of the function of genes on the courseof renal disease in experimental animal models and (ii) themodulation of local expression of endogenous genes which presumptivelycontribute to renal pathology in these models. One strategyto accomplish this aim is the use of recombinant DNA technologyto design antisense DNA constructs or oligonucleotides, whichinterfere with the renal expression of target genes. We willalso discuss some of the shortcomings of the currently usedtechniques with respect to potential therapeutic use of genetransfer systems and gene modulation.  相似文献   
57.
The announcement of the National Heart Attack Alert Program by the National Heart, Lung and Blood Institute in June of 1991 prompted leaders of the Florida Chapter of the American College of Cardiology to develop a statewide program to reduce the morbidity and mortality from acute myocardial infarctions within Florida. It became apparent that the success of such a program would require the prompt institution of thrombolytic agents or other revascular-ization procedures in appropriate patients. No longer could the decision regarding institution of therapy await discussion by telephone and/or the arrival at the emergency department (ED) of the patient's primary care physician or cardiologist. Efforts to establish appropriate protocols for therapy revealed that many of the 25,000 or more physicians currently staffing the 5,600 or so EDs in this country were moonlighting residents or practitioners from a variety of specialties or subspe-cialties with limited or no formal EM training. Furthermore, it was learned that there were in the entire country only about 800 postgraduate, year-one Council for Graduate Medical Education accredited training positions. There were only 21 such training positions in the entire state of Florida. The reasons for these deficiencies are discussed and a challenge to correct this person power crisis is issued, not principally to the leadership of EM, but to the entire medical profession.  相似文献   
58.
急性心肌梗塞患者血清唾液酸含量测定   总被引:2,自引:0,他引:2  
本文测定了50例正常人,32例急性心肌梗塞,54例冠心病无梗塞者血清SA水平,结果表明,急性心肌梗塞组血清SA水平与冠心病无梗塞组及正常人相比,具显著性差异,可能与心肌梗塞造成心肌细胞受损所致使细胞表面成份释放入血有关,所以血清SA测定可提供一新的心肌梗塞诊断依据。  相似文献   
59.
The influence of a fraction obtained from Galeopsis ladanum L. on the central nervous system of rodents was examined. The results of these investigations show that the fraction impeded CNS activity. It is practically nontoxic and at a dose of 2000 mg/kg i.p. it does not have a soporific influence on mice. It reduces considerably the spontaneous locomotor activity of mice as well as the locomotor activity of mice stimulated by caffeine, but did not influence the locomotor activity induced by amphetamine. The extract did not exhibit a synergetic effect with barbiturates. The results suggest that the pharmacological activity of the extract resembled the activity of drugs which generally depress the CNS, being on the border between ataractic and sedative drugs.  相似文献   
60.
Congenital agranulocytosis terminating in acute myelogenous leukemia has been previously reported in only two cases of adolescent males. We describe the clinical and laboratory features of a 13-year-old male with congenital agranulocytosis, treated with G-CSF with initial good neutrophil response, who subsequently developed acute myeloid leukemia. This rare complication may define a preleukemic subset of patients for whom G-CSF therapy is ineffective. The diagnostic challenges of this case are presented.  相似文献   
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