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51.
In an infant with Menkes's steely-hair syndrome, early treatment (from 21 days of age) with parenteral copper failed to halt the disease. In addition to urinary tract abnormalities, panlobular emphysema was present a finding not previously noted in the syndrome.  相似文献   
52.
A history of pet contact and/or apparent clinical sensitivity was obtained in 65 (55%) of 118 unselected asthmatic children. These 65 children were skin tested and their sera examined for specific IgE using the radioallergosorbent test. Those children who had apparent clinical sensitivities had larger skin test reactions and were more likely to have positive specific IgE results than those without apparent sensitivities. Positive skin tests were very common (80%), but the larger the skin test reaction (weal diameter greater than 4 mm diameter) the more likely was there to be a positive history or a positive specific IgE result. Hence a large skin test reaction can provide a helpful pointer to animal allergy of clinical importance. Commercially available animal extracts have limitations for diagnostic tests. A questionnaire survey of 150 day schools emphasized the potential opportunities for contact with animal allergens at school.  相似文献   
53.
High-dose intravenous gammaglobulin (IVIgG) was given to 12 children and adults with chronic idiopathic thrombocytopenic purpura (ITP) to avoid splenectomy or because they either failed to respond to or required maintenance with high doses of steroids and/or immunosuppressives. The average platelet count increase to initial therapy was 239,500/microliters (range 23,000-790,000). A concomitant IgG Fc receptor blockade, measured by IgG-sensitized 51Cr-labeled autologous erythrocytes, was seen in 11 of 11 patients tested, both splenectomized and not splenectomized, lasting 3-4 wk. Six or more months after treatment, 2 children are in remission, 2 children and 2 adults are stable requiring no therapy with platelet counts of approximately 50,000 and 30,000, respectively, 3 children require maintenance IVIgG therapy at 2-10-wk intervals, and 1 child and 2 adults have become refractory to further IVIgG. Splenectomy was not performed in 4 children. Two adults were able to discontinue daily prednisone. The 3 patients who became unresponsive to Swiss Red Cross gamma-globulin (IgSRK) therapy did so in conjunction with a markedly elevated platelet-associated IgG and IgM. Serum IgM increased an average of 103 mg/dl after the IVIgG infusions. No significant side effects were seen.  相似文献   
54.
Grade progression and regression in recurrent urothelial cancer   总被引:3,自引:0,他引:3  
PURPOSE: Recurrent urothelial cancers are reported to have characteristics similar to those of the primary tumor, with 10% to 25% of low grade tumors recurring as high grade disease. We determined how often grade progression and regression occur and whether abnormalities in p53 protein expression in original tumors are preserved in recurrences. MATERIALS AND METHODS: Two groups of patients treated for recurrent stages Ta/T1 urothelial bladder cancers with at least 1 tumor-free examination between the index and recurrent tumors were reviewed. Group 1 included 115 patients in whom the first available tumor was compared with the last recurrence and group 2 included 42 in whom the initial tumor was compared with the first recurrence. Immunohistochemical analysis of p53 expression was performed on a subset of 34 tumor pairs. RESULTS: In group 1, 33 grade 3 tumors (45%) recurred as grade 1 or 2 tumors, while 9 of 82 grades 1 and 2 tumors (11%) recurred as grade 3 tumors. Five of 7 group 2 grade 3 tumors (71%) recurred as grade 1 or 2 disease, while 1 of 35 grades 1 and 2 tumors (3%) recurred as grade 3 disease. In the 34 pairs studied immunohistochemically 6 of 14 grade 3 tumors recurred at lower grades. Nuclear p53 over expression occurred in 21 index tumors (12 of 14 grade 3, 8 of 17 grade 2 and 1 of 3 grade 1) and in 9 recurrences (6 of 10 grade 3, 2 of 17 grade 2 and 1 of 7 grade 1). Only 7 of 21 p53 positive and 2 of 12 p53 negative index tumors were p53 positive on recurrence. CONCLUSIONS: While progression from low to high grade occurred in less than 15% of patients, grade regression was observed in almost 50%. The loss of p53 positivity in regressing tumors indicates that these recurrences are molecularly distinct from the corresponding initial tumor.  相似文献   
55.
Ethanol can injure the nervous system by disturbing the growth of neural processes. PC12 cells, which form neurites in response to nerve growth factor (NGF), fibroblast growth factor (FGF), and cAMP analogues, were used to study mechanisms by which ethanol alters process outgrowth. Ethanol potentiated NGF-induced neurite outgrowth in cells cultured on different substrata and in serum-containing or defined medium. Ethanol did not increase NGF receptor binding or internalization of NGF. Neurite outgrowth induced by basic FGF was also increased by ethanol but outgrowth induced by forskolin was not. Ethanol potentiated NGF-induced expression of Thy-1, but not of neural cell adhesion molecule (N-CAM), indicating that some, but not all actions of NGF are enhanced by ethanol. In some brain regions, chronic exposure to ethanol increases the growth of dendrites. This has been explained as a compensatory response of surviving neurons to the loss of neighboring cells, and not as a direct effect of ethanol. The present findings suggest that, in some cells, ethanol directly promotes growth factor-mediated neurite formation. This could harm the nervous system by disturbing the balanced development and organization of synapses.  相似文献   
56.
SUMMARY Serum potassium was measured within 24 hours in 156 patients (48 male, 108 female) with an average age of 81.9 years admitted to the unit with acute illness. Of the 156 patients, 88 (56.4%) were taking diuretics (none was on ACE inhibitors); 20 patients (12.8%) were also on digoxin therapy. In all, 24 patients (16%) had hypokalaemia and 3 (2%) hyperkalaemia. Hypokalaemia was seen in patients associated with acute illness. There was no significant difference between the diuretic and non-diuretic groups. Monitoring of serum potassium is not routinely indicated to detect hypokalaemia in patients on diuretic therapy except in those with severe hepatic or renal impairment or those on digoxin.  相似文献   
57.
Low-level echogenicity in intraventricular hemorrhage versus ventriculitis   总被引:1,自引:0,他引:1  
Grant  EG; White  EM; Schellinger  D; Rosenbach  D 《Radiology》1987,165(2):471-474
Serial cranial sonograms of 55 neonates with large perinatal intraventricular/intraparenchymal hemorrhages and moderate-to-severe posthemorrhagic hydrocephalus were reviewed. In all 55 patients, the ventricles were initially enlarged and filled with anechoic cerebrospinal fluid, which contained discrete hyperechoic fragments of hematoma. Between 7 and 25 days after the initial hemorrhagic episode, however, diffuse, low-level echogenicity appeared in the ventricles of 34 patients. The low-level echogenicity was transient and persisted for 7-59 days (average, 18 days). In 32 patients, low-level echogenicity was a benign finding associated with prior intraventricular hemorrhage. In two patients, the low-level echogenicity was associated with ventriculitis. Low-level echogenicity appeared, increased, then cleared, but reappeared with the onset of ventriculitis in these two patients. Thickening of the ependyma and abnormal periventricular echogenicity, signs of inflammation, were also present. Although low-level echogenicity may commonly be a benign finding, the possibility of ventriculitis should not be ignored.  相似文献   
58.
Aim: The aim of this study was to investigate heart rate variability (HRV) in a clinical sample of female adolescents with anxiety disorders (AD) and/or major depressive disorder (MDD) compared with healthy controls and to assess the effect of selective serotonin reuptake inhibitors (SSRI) on HRV. Methods: Heart rate variability was measured in adolescent female psychiatric patients with AD and/or MDD (n = 69), mean age 16.8 years (range: 14.5–18.4), from 13 out‐patient clinics and in healthy controls (n = 65), mean age 16.5 years (range: 15.9–17.7). HRV was registered in the sitting position during 4 min with no interventions. Results: Logarithmically transformed high frequency HRV (HF), low frequency HRV (LF) and standard deviation of inter beat intervals (SDNN) were lower in the clinical sample compared with the controls (Cohen’s d for HF = 0.57, LF = 0.55, SDNN = 0.60). This was not explained by body mass index, blood pressure or physical activity. Medication with SSRI explained 15.5% of the total variance of HF, 3.0% of LF and 6.5% of SDNN. Conclusions: Adolescent female psychiatric patients with AD and/or MDD show reduced HRV compared with healthy controls. Medication with SSRI explained a part of this difference.  相似文献   
59.
口服Carvedilol治疗心力衰竭多中心研究(MOCHA)   总被引:1,自引:0,他引:1  
标题 Carvedilol对慢性心力衰竭患者左心室功能的改善和存活的提高呈剂量相关性作者 BristowMR,GilbertEM,AbrahamWT,等  Circulation1996,94:2807~2816  研究疾病:充血性心力衰竭。目的:对Carvedilol治疗慢性心力衰竭患者剂量-疗效特征进行评价。  设计:随机、双盲、安慰剂对照的多中心研究,剂量效应关系研究。病人资料:共345名心力衰竭患者,年龄18~85岁,左室射血分数≤0-35,心力衰竭症状时间≥3月,研究前所有患者必须用利…  相似文献   
60.
Cultures of human normal urothelial (HU) cells and transitional cell carcinoma (TCC) cell lines were tested for their ability to specifically bind and respond to epidermal growth factor (EGF). The criteria of response investigated were stimulation of growth and induction of ornithine decarboxylase (ODC) activity. All four human TCC cell lines tested were stimulated to grow by EGF (1-100 ng/ml) in a dose related fashion while only one of four HU cell cultures was similarly stimulated, and growth stimulation of this cell line occurred only at early passage. TCC and HU cells bound EGF to similar degrees with Kds of 0.86 nM for TCC and 2.54 nM for HU (P greater than 0.05) and 91637 +/- 9816 (SD) (high affinity) receptors/cell for TCC and 124275 +/- 16841 for HU (P greater than 0.10). Baseline ODC activity was statistically similar in the two TCC and the three HU cell cultures tested. However, EGF induced dose related ODC activity only in the TCC cell lines and not in any of the HU cell cultures. Thus, while both malignant and normal urothelium bind EGF equally well in vitro, only TCC responds to EGF in two parameters relevant to neoplasia: growth and induction of ODC activity.  相似文献   
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