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991.
Scientific-Research Center of Biomedical Radioelectronics, Moscow. Translated from Meditsinskaya Tekhnika, No. 6, pp. 36–37, November–December, 1992.  相似文献   
992.
993.
What is clusterin?   总被引:1,自引:1,他引:0       下载免费PDF全文
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994.
Ultrasonography was performed in 661 dialysis patients and acquired cystic disease of the kidney was found in 156 (125 men and 31 women). A higher incidence of cystic disease was found in males. There was no significant difference between the patients with and those without acquired cystic disease in terms of average age, but the duration of haemodialysis in those with acquired cystic disease was significantly longer. There was an increased incidence of cystic disease in patients with glomerulonephritis and the duration of haemodialysis in these patients was significantly longer. This suggests that the increased incidence of acquired cystic disease of the kidneys in the patients with glomerulonephritis is simply related to the longer duration of treatment. Twelve patients with renal carcinoma were found in this study. The average age at diagnosis of renal carcinoma was not significantly different between the patients with and those without acquired cystic disease, but the duration of dialysis was significantly longer in renal carcinoma patients with acquired cystic disease. The incidence of renal carcinoma in dialysis patients with acquired cystic disease was 3.85% and in those without it was 1.19%. These rates are considerably higher than those found in the general population and indicate that the risk of renal carcinoma is higher in dialysis patients both with and without acquired cystic disease.  相似文献   
995.
Ten patients with osteosarcomas and rotation plasties made themselves available for a psychological survey. The time elapsed after their operations was between two and ten years, giving an average of six years. All patients were free of tumours at the time of the follow-up examination. Both in personal interviews and in psychological tests, it was possible to observe a very positive development of these patients' attitudes. Contributory factors in this context were discussions with the doctors administering treatment, the cheerful atmosphere of the hospital and the nursing staff, the physicotherapists and ergotherapists, and the excellent social support which all those interviewed also received from their relatives. Continuous positive motivation, a favourable social dialogue and patients' ability to control their own lives would appear to be the key factors in helping patients to come to terms with their illness.  相似文献   
996.
997.
T Hibi  N Shitara  S Genka  T Fuchinoue  I Hayakawa  T Tsuchida  K Nomura  T Kondo  K Takakura 《Neurosurgery》1992,31(4):643-50; discussion 650-1
An analysis of 39 patients under 20 years of age with brain stem glioma treated with radiotherapy between 1977 and 1991 was undertaken. Twenty-eight (71.2%) of the patients responded well to initial radiotherapy, and 11 (28.8%) responded poorly. Median survival for the total patient population was 10 months. Response rates and median survivals were influenced by radiation dose: 45.5% and 9 months at doses less than 4499 cGy (n = 11), 83.3% and 13 months at doses between 4500 and 5499 cGy (n = 12), 66.7% and 11.5 months at doses between 5500 and 6499 cGy (n = 9), and 100% and 10 months at doses more than 6500 cGy (n = 7). Multivariate analysis revealed the response to initial radiotherapy was the only predictor of survival with radiation doses up to 6499 cGy. Four of the patients who responded well demonstrated radiological and/or histological calcification within or around the tumor at the time of clinical deterioration. Radiation injury was confirmed in two autopsy cases. The possibility that intratumoral radiation injury causes clinical deterioration is suggested.  相似文献   
998.
We have developed an immunoadsorbent (IA) for ex vivo removal of IgE after in vitro screening of matrix (Sepharose and tresyl-activated Toyopearl) and ligand (monospecific rabbit polyclonal anti-IgE antiserum and monoclonal antibodies (Abs) or their Fab fragments). Specific adsorptive capacity (SAC) for IgE was maximal in Sepharose-based IA with both types of Abs. Fab-containing IA on Sepharose retained 70-90% of the SAC of native Ab-containing IA. Toyopearl-based IA showed comparable SAC under static conditions but worked unsatisfactorily under continuous flow conditions. To assess the complement-activating capacity (CAC) of IA in vitro anaphylatoxin (C3a, C4a, C5a) generation was applied. CAC was directly related with the amount of immobilized Ab ligand, without depending on Ab specific activity. Fab-containing IA showed more CAC than native Ab-containing IA, and polyclonal IA more than monoclonal IA. Therefore, IA for IgE apheresis were prepared from native monoclonal Abs and CNBr-activated Sepharose CL 4B under aseptic conditions and packed into a glass column. This IA was used in 17 clinical IgE apheresis treatments of five atopic asthma patients. No substantial side effects were observed; in vivo IA effectively removed IgE from plasma (83 to 98%).  相似文献   
999.
Aims In an attempt to reverse multidrug resistance, in a recent trial of verapamil in association with doxorubicin, we used escalating doses of continuous intravenous (i.v.) verapamil under close haemodynamic monitoring. We report the pharmacokinetics of escalating doses of verapamil. Methods We studied nine patients [ seven males, two females; median age 46 years (range, 31–57)] with advanced adenocarcinoma of the colon and normal renal, hepatic, and cardiac functions. After a loading dose (0.15 mg kg−1 followed by 12 h continuous i.v. infusion at 0.20 mg kg−1 h−1 ), the infusion rate (ko) of verapamil was increased every 24 h (0.25, 0.30, 0.35, and 0.40 mg kg−1 h−1 ). The highest rate was maintained for 48 h. Doxorubicin was given as a continuous i.v. infusion from 12 to 108 h (n=4) or 60 to 108 h (n=5). Blood samples and urine collections were taken every 12 h. Verapamil and nor-verapamil were assayed by high performance liquid chromatography. We calculated systemic clearance of verapamil (CL=ko/Css ) and renal clearance (CLr) of verapamil and nor-verapamil. The Cssvs rate relationship was fitted to a Michaelis-Menten equation: Css=ko(Km+Css )/(V Vm ). Results CL was dose-dependent and in all nine patients a significant reduction in CL was observed over the dose range (mean CL±s.d. were 0.51±0.31, 0.38±0.16, 0.32±0.18, and 0.27±0.11 l h−1 kg−1, respectively, at 0.25, 0.30, 0.35, and 0.40 mg kg−1 h−1; P=0.0001). Css increased more than proportionally to the dose rate and the Cssvs rate relationship was best defined by a Michaelis-Menten equation (Km=730 μg l−1; V Vm=0.55 mg kg−1 h−1 ), (r=0.994; P=0.006). CLr of verapamil and nor-verapamil was not saturable but the contribution to the elimination was only 2 to 4% of the dose. Conclusions These findings suggest a non-linear, capacity-limited metabolic clearance of high-dose verapamil. Using escalating infusion rates, high verapamil concentrations (1500–2500 ng ml−1 ) were achieved without major toxicity. Saturable clearance may cause higher bioavailability and slower elimination of verapamil after acute oral overdoses.  相似文献   
1000.
1. As part of a broader study to characterize neuronal purinoceptors, the effects of adenosine 5'-triphosphate (ATP) and a range of ATP analogues were investigated on the extracellularly recorded membrane potential of the rat isolated vagus nerve, using a 'grease-gap' technique. 2. ATP evoked depolarization of the rat vagus nerve. The concentration-effect curve to ATP was not monophasic: at the lower concentrations (1 x 10(-5)-1 x 10(-3) M) the curve was shallow (< 50% of the near maximal response to 5-hydroxytryptamine (5-HT)) whilst at higher concentrations the relationship between concentration and amplitude of depolarization was steeper (> 135% of the response to 5-HT at the highest concentration tested, 1 x 10(-2) M). On washout of the high drug concentrations large after-hyperpolarizations were often observed. 3. alpha,beta-methylene ATP (1 x 10(-6)-3 x 10(-4) M), beta,gamma-methylene ATP (1 x 10(-6)-1 x 10(-3) M), and 5'-adenylylimidodiphosphate (beta,gamma-imido ATP; 1 x 10(-6)-1 x 10(-3) M) were all more potent than ATP and produced large depolarizations of the rat vagus nerve at the highest concentrations tested (> 150% of the response to 5-HT). The overall rank order of potency was alpha,beta-methylene ATP > beta,gamma-methylene ATP = beta,gamma-imido ATP > ATP. 4. In contrast, 2-methylthio ATP (1 x 10(-6)-1 x 10(-3) M) produced relatively small depolarizations (< 100% of the response to 5-HT). As was the case with low concentrations of ATP, the concentration-effect curve to 2-methylthio ATP was very shallow.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
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