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11.
Twenty heterophoric and 10 heterotropic patients with long standing severe visual symptoms were corrected with prisms for permanent wearing using the full-correction method of H.-J. Haase. The patients were reexamined 1 and 5 years after completion of treatment. Stable corrections obtained by stepwise optical full-correction were also maintained during a follow-up period of 5 years. Sensory and motor adaptations were largely removed and asymptomatic binocular vision was obtained for nearly all patients. A few cases of partly irreversible amblyopia were indicated, but even in these cases largely normal binocular functions were attained. When glasses were suspended, sensory and motor readaptations took place.  相似文献   
12.
1. The effect of strophanthidin on the slow inward current (Isi) and on contractile force were studied in guinea-pig isolated ventricular myocytes and intact papillary muscles, respectively. In myocytes, both low (10 nmol/L) and high (1-10 mumols/L) concentrations had small or no effects in either direction on Isi whereas norepinephrine (10-100 nmol/L) increased it. To determine whether the same results are obtained after decreasing or increasing intracellular calcium or sodium, the same concentrations of strophanthidin were tested in different procedures that are known to (i) increase [Ca]i and decrease [Na]i (high [Ca]o, 3.6-5.4 mmol/L; low [Na]o, 112 mmol/L; (ii) decrease [Ca]i and increase [Na]i (low [Ca]o, 0.45-1 mmol/L; Sr, 1 mmol/L; (iii) decrease [Ca]i and [Na]i (Cd, 0.1-0.2 mmol/L); and (iv) increase [Ca]i and [Na]i (veratridine, 0.2 mumol/L). High [Ca]o and veratridine increased whereas low [Ca]o and Cd decreased Isi. In contrast, during these various procedures, strophanthidin had small and inconsistent effects at a low or high concentration. In intact papillary muscles, low strophanthidin decreased whereas high strophanthidin increased contractile force. It is concluded that strophanthidin has little direct or indirect effect on Isi and that the decrease in force by low and increase in force by high concentrations in intact muscle are probably related to demonstrated decrease and increase, respectively, in intracellular sodium activity.  相似文献   
13.
岛津数字胃肠机IF OVER故障产生的原理及维修   总被引:1,自引:0,他引:1  
雷烈 《医疗设备信息》2007,22(6):113-113
分析了岛津3200数字胃肠机IFOVER故障产生的原因,并结合实际故障现象,具体介绍了排除方法。  相似文献   
14.
本文通过分析近5年来我院18例女性直肠癌全直肠系膜切除术后直肠阴道痿的临床资料。发现直肠阴道痿多发生于中低位直肠癌行全直肠系膜切除保肛手术的患者。痿的发生与肿瘤的位置、肿瘤的分期、肿瘤距肛门口的距离.以及手术技巧、手术难度、引流方法有关。而与是否进行预防性造口,以及是否采用腹腔镜手术无关。预防上强调应重视术中直肠前壁的锐性分离、结肠直肠吻合以及术后盆腔的负压引流。治疗上应首先进行保守治疗,即肠内营养,阴道冲洗。早期配合肠外营养、及全身或局部抗炎治疗,大部分直肠阴道痿通过保守治疗可以治愈。保守治疗无效时考虑结肠或回肠末端造口。若长期不愈应考虑吻合口肿瘤复发的可能。  相似文献   
15.
胶原基真皮再生支架的微结构控制   总被引:6,自引:0,他引:6  
综述了影响胶原基真皮再生支架微结构的各种因素及其控制方法。胶原基真皮支架的生物活性和修复创面的能力受到诸如除胶原外的其它主要材料 (第二组分 )、支架的孔径和孔隙率、支架厚度、生物活性因子以及交联度等多方面因素的综合影响。从材料学、生物学和医学的角度综合地应用物理、化学和生物学的手段探索各种影响因素的控制方法是组织工程皮肤研究的重点。  相似文献   
16.
Alleles of HLA class II genes DQB1, DQA1, and DRB1 in the MHC region are major determinants of genetic predisposition to type 1 diabetes (T1D). Several alleles of each of these three loci are associated with susceptibility or protection from disease. In addition, relative risks for some DR-DQ genotypes are not simply the sum or product of the single haplotype relative risks. For example, the risk of the DRB1*03-DQB1*02/DRB1*0401-DQB1*0302 genotype is often found to be higher than for the individual DRB1*03-DQB1*02 and DRB1*0401-DQB1*0302 homozygous genotypes. It has been hypothesized that this synergy or epistasis occurs through formation of highly susceptible trans-encoded HLA-DQ(alpha 1, beta 1) heterodimers. Here, we evaluated this hypothesis by estimating the disease associations of the range of DR-DQ genotypes and their inferred dimers in a large collection of nuclear families. We determined whether the risk of haplotypes in DRB1*0401-DQB1*0302-positive genotypes relative to the DRB1*03-DQB1*02-positive genotypes is different from that of DRB1*01-DQB1*0501, which we used as a baseline reference. Several haplotypes showed a different risk compared to DRB1*01-DQB1*0501, which correlated with their ability to form certain trans-encoded DQ dimers. This result provides new evidence for the potential importance of trans-encoded HLA DQ molecules in the determination of HLA-associated risk in T1D.  相似文献   
17.
Positive selection plays a role, together with negative selection, in the prevention of autoimmunity. Thymus-specific serine protease is highly expressed in the thymus and is believed to be involved in positive selection of T cells. The gene encoding thymus-specific serine protease (PRSS16) maps to the extended HLA complex, which harbours several genes predisposing for autoimmune diseases. Here we report the results of scanning the genetic region containing PRSS16 for polymorphisms. Twenty-two polymorphisms were identified, including one missense polymorphism, one deletion leading to elimination of five amino acids, as well as several SNPs in the promoter region.  相似文献   
18.
Isolated polyarteritis of testis in hairy-cell leukemia   总被引:1,自引:0,他引:1  
A polyarteritis nodosalike systemic vasculitis in hairy-cell leukemia was first reported in 1979, and since then at least 30 additional cases of this unusual association have been reported in the literature. Reported herein is, to my knowledge, the first known example of hairy-cell leukemia with necrotizing vasculitis limited to the testis only.  相似文献   
19.
Measurements of anesthetized dogs by the heat-accumulation technique showed that cyanide reduced equally the metabolic rates of outer medulla and cortex, whereas combined infusion of ethacrynic acid and chlorothiazide reduced mainly the metabolic rate of the outer medulla. During ethacrynic acid and chlorothiazide infusion, cyanide reduced the remaining sodium reabsorption by an average of 19% and the remaining cortical metabolic rate by 43%, but had no additional effect on the outer medullary metabolism. Metabolic rates remained essentially constant when glomerular filtration rate (GFR) was raised during cyanide infusion from 63 plus or minus 3 to 135 plus or minus 7% of control by carotid constriction or intravenous infusion of angiotensin. Glomerulotubular balance, defined as proportional relationship between sodium reabsorption and GFR during infusion of ethacrynic acid and chlorothiazide, was present only at GFR less than 80% of control in experiments with and without cyanide infusion. We conclude that cyanide inhibits proximal energy-requiring sodium transport which cannot be inhibited by ethacrynic acid and chlorothiazide, but does not alter the range of GFR over which glomerulotubular balance applies.  相似文献   
20.
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