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1.
The authors report the case of a woman admitted to hospital for minor trauma of the left hip and who presented major ST segment elevation on the second day suggesting an acute anterior wall myocardial infarction at the same time as a cerebrovascular accident. Complementary investigations and follow-up excluded the diagnosis of myocardial infarction with normalisation of the ECG on the 5th day. ECG changes during cerebrovascular accidents may be very variable ranging from extrasystoles to ST elevation mimicking myocardial infarction. They carry a poor prognosis with an increased risk of sudden death necessitating continuous ECG monitoring until the ECG reverts to normal. The cardiac involvement is not ischaemic but due to disease of the insular cortex of the brain which induces myocytolysis (centered around the intra-cardiac nerve endings) due to the sudden liberation of catecholamines. These lesions may be treated by propranolol or phentolamine.  相似文献   
2.
A prospectively studied group of 55 uncemented Press Fit Condylar total knee arthroplasties was compared retrospectively with a matched group of 51 cemented Press Fit Condylar total knee arthroplasties at a mean of 10 years after operation. For the cemented group, the pain and function scores improved from 32 and 45 preoperatively to 95 and 77, respectively. For the uncemented group the scores improved from 33 and 50 preoperatively to 93 and 60, respectively. There were 10 revisions in the uncemented group for femoral or tibial aseptic loosening or osteolysis compared with two revisions in the cemented group. Exclusive of problems related to patellar metal backing, survival to revision for aseptic failure or radiographic loosening was 72% in the uncemented group and 94% in the cemented group at 10 years. A significantly higher revision rate was found in the uncemented compared with cemented total knee arthroplasty of the Press Fit Condylar design.  相似文献   
3.
Using ion exchange chromatography and an ATP-dependent actin precipitation step, we have isolated three myosin-I isozymes that, together, account for most of the K+EDTA-ATPase activity recovered from extracts of Dictyostelium. The two major myosin-I isozymes, present in approximately equal amounts, had apparent molecular masses of 125 kDa on SDS gels and have been identified by amino acid sequence analysis as the products of the Dictyostelium myosin-IB (DMIB) and myosin-ID (DMID) genes. DMIB, with a specific K+EDTA-ATPase activity 10-fold higher than DMID, was responsible for most of the activity in cell extracts. The third isozyme, present in low amounts, had an apparent molecular mass of 137 kDa on SDS gels and is too large to be the product of any of the known myosin-I genes. DMIB eluted from DE53 cellulose columns as two distinct peaks (II and III). Addition of the phosphatase inhibitor okadaic acid to the extraction buffer increased the fraction of DMIB recovered from growth phase cells in peak III from 35 to 70%. DMIB isolated from peak III, but not from peak II, displayed a significant level of actin-activated MgATPase activity. These results indicate that peak III represents a phosphorylated, actin-activatable form of DMIB.  相似文献   
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BACKGROUND: The association of serum lipids with coronary heart disease has been studied extensively in middle-aged men and, to a lesser extent, in similar women. Less well defined are lipid variables predictive of CHD in individuals of age > or = 60 years. METHODS AND RESULTS: The Systolic Hypertension in the Elderly Program recruited 4736 persons (mean age, 72 years; 14% were black; and 43% were men). Mean systolic and diastolic blood pressures were 170 and 77 mm Hg, respectively. Baseline mean total cholesterol was 6.11 mmol/L (236 mg/dL); HDL cholesterol, 1.39 mmol/L (54 mg/dL); and non-HDL cholesterol, 4.72 mmol/L (182 mg/dL). Triglyceride levels were 1.62 mmol/L (144 mg/dL) for fasting participants and 1.78 mmol/L for the total group. LDL cholesterol, estimated in fasting samples with triglycerides of < 4.52 mmol/L, averaged 3.98 mmol/L (154 mg/dL). Mean follow-up was 4.5 years. In multivariate Cox regression analyses, baseline total, non-HDL, and LDL cholesterol levels and the ratios of total, non-HDL, and LDL to HDL cholesterol were significantly related to CHD incidence. HDL cholesterol and triglycerides were not significant in these analyses. In fasting participants with triglyceride levels of < 4.52 mmol/L, a 1.03 mmol/L (40 mg/dL) higher baseline total, non-HDL, or LDL cholesterol was associated with a 30% to 35% higher CHD event rate. CONCLUSIONS: The results of this study support the concept that serum lipids are CHD risk factors in older Americans.  相似文献   
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The wakefulness-sleep cycle characteristics changes in Wistar line rats after unilateral lesions of the neuronal elements of the caudate nucleus head with kainic acid (at sparing the conducting ways going through this structure) were studied. It was shown that in 4 days after acid injection the share of the active wakefulness and light slow-wave sleep is significantly increased, whereas the percentage of the passive wakefulness, deep slow-wave stage, and paradoxal sleep (up to 80%) is reduced. The wakefulness-sleep cycle in rats is completely normalized on the 7th day after injection. The obtained data allow to consider the caudate nucleus as a modulator for wakefulness-sleep cycle, that is the structure involved in the motive activity regulation.  相似文献   
8.
Temperature-regulated expression of recombinant proteins in the tac promoter (Ptac) system was investigated. Expression levels of fungal xylanase and cellulase from N. patriciarum in E. coli strains containing the natural lacI gene under the control of the Ptac markedly increased with increasing cultivation temperature in the absence of a chemical inducer. The specific activities (units per milligram protein of crude enzyme) of the fungal xylanase and cellulase produced from recombinant E. coli strain pop2136 grown at 42 degrees C were about 4.5 times higher than those of the cells grown at 23 degrees C and were even slightly higher when compared with cells grown in the presence of the inducer isopropyl beta-D-thiogalactopyranoside. The xylanase expression level in the temperature-regulated Ptac system was about 35% of total cellular protein. However, this system can not be applied to E. coli strains containing lacIq, which confers over production of the lac repressor, for high-level expression of recombinant proteins. In comparison with the lambda PL system, the Ptac-based xylanase plasmid in E. coli pop2136 gave a considerably higher specific activity of the xylanase than did the best lambda PL-based construct using the same thermal induction procedure. The high-level expression of the xylanase using the temperature-regulated Ptac system was also obtained in 10-litre fermentation studies using a fed-batch process. These results unambiguously demonstrated that the temperature-modulated Ptac system can be used for overproduction of some non-toxic recombinant proteins.  相似文献   
9.
Belonging to the Annonaceae family, marolo (Annona coriaceae) is a native species of the Brazilian "cerrado" región (Minas Gerais, Goiás and Distrito Federal) and can be found in South American tropical zones. Its fruits are highly consumed by local people and commercialized in markets or street stalls. There is, however, a tendency for the extinction of marolo due to deforestation and the large scale plantation of monocultures instead of native plants. The literature still offers no data on the chemical composition of the proximate composition and vitamin C, A and tannin contents were carried out on the yellow marolo pulp as well as the determination of the physico-chemical characteristics of the seed oil. Five batches of fruit from the Alfenas region--south of Minas Gerais State--were analysed in this work and their average composition were: humidity 77%, total sugar 15%, reducing sugar 11%, crude protein 1%, lipids 3%, fiber 5% and fixed mineral residue 1%. The contents of vitamin C and A were 8.2 mg/100g and 117.5 RE/100g, respectively, and the tannin content was 245 mg/100g. The results showed high fiber and lipid contents of marolo pulp in comparison with many other tropical fruit pulps. The vitamin C contents were equivalent to those found in avocado, pineapple and watermelon, while the vitamin A contents were equivalent to papaya, peach, guava and several other tropical fruits. Marolo seed contains 45% of oil on a dry basis. Its composition and physico-chemical characteristics showed the possibility of producing a good quality oil, with great potential for the fine oil market. However the presence of alkaloids in the oil needs to be further studied. Their elimination could be done by refining or extraction in a continuous press. The results exalt the high quality of marolo pulp, showing that the preservation of native species should be stimulated.  相似文献   
10.
BACKGROUND: The aim of the study is to determine what concentration of ketorolac and morphine administered together i.v. achieve best synergic effect between NSAID antiinflammatory and opioids analgesic properties. DESIGN: Randomized comparative study was carried out on 180 patients, ASA II-IV, undergoing major general surgery, in an University Clinic. METHODS: Postoperative pain therapy by i.v. PCA: group 1 morphine 0.75 mg.ml + ketorolac 0.75 mg.ml; group 2 morphine 0.50 mg.ml + ketorolac 1.50 mg.ml; group 3 morphine 0.25 mg.ml + ketorolac 1.50 mg.ml; in saline solution. Initial bolus: 2 ml. Continuous infusion 1.5 ml.h. Demand bolus: 0.2 ml. Lockout time: 30 minutes. Evaluations included: pain intensity (T0, T3, T18); total amount of infused drugs (T18); number of valid demands and attempts (T18); amount of autoadministered analgesic drugs in percent of highest available amount (T18); side effects (T18); patient's judgment. DATA ANALYSIS: ANOVA and Student's "t"-test. RESULTS: A statistically significant reduction of pain intensity was found after 3 and 18 hours in the three groups, no differences were found among the groups. Group 2 required an amount of autoadministered drugs significantly lower than other groups. Rare side effects. Patient's judgment was generally positive. CONCLUSIONS: Results suggest a greater synergetic effect between morphine and ketorolac in concentrations used in group 2.  相似文献   
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