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191.
Factor VII and extrinsic pathway inhibitor in acute coronary disease   总被引:1,自引:0,他引:1  
This report describes studies on the activation of coagulation factor VII (FVII) and the inhibition of the extrinsic coagulation pathway in acute ischaemic heart disease. FVII and the inhibitor of the tissue thromboplastin-FVII complex, called extrinsic pathway inhibitor (EPI), were determined in plasma from 68 patients and compared to findings in 37 normal individuals. The mean FVII amidolytic activity, the mean FVII clotting activity, as well as the FVII clotting/FVII amidolytic ratio were not significantly different in the patient groups as compared to the controls. The fraction of FVII clotting activity that is sensitive to phospholipase C, 'the FVII-phospholipid complex', was 8% in controls, 19% (P less than 0.05) in patients with acute myocardial infarction, 15% (n.s.) in angina pectoris and 13% (n.s.) in heart failure/arrhythmia patients. The 'FVII-phospholipid complex' was highly significantly correlated to triglycerides in plasma in patients with acute myocardial infarction (r = 0.88, P less than 0.001) and angina pectoris (r = 0.89, P less than 0.001). The mean EPI levels were significantly increased in patients with acute myocardial infarction (132%), angina pectoris (134%), and heart failure (150%) as compared to the control population (110%). The FVII clotting/EPI ratio was significantly decreased both in patients with acute myocardial infarction and heart failure, whereas the FVII amidolytic/EPI ratio was significantly decreased only in the heart failure group. Apparently, in patients with acute ischaemic heart disease, a moderate increase in the procoagulant activity is accompanied by a marked increase in the anticoagulant activity of the extrinsic coagulation pathway, suggesting a balanced activation system.  相似文献   
192.
Several tuberculins, strengths and setting methods are in everyday use. We wanted to compare the Norwegian reference adrenaline Pirquet test with the internationally recommended Mantoux PPD test and Rhoditest. In responders of a random sample of young adults, with randomization of test subjects, we intra-individually compared the adrenaline-Pirquet (aP) test with Norwegian-produced synthetic medium tuberculin (SMT) with either the Mantoux test with PPD 2 tuberculin units (TU) (M2), the Mantoux-PPD 5 TU (M5) or the PPD 2 TU-Rhoditest (Rh). The criteria for a positive reaction were > or = 4mm for the aP test, > or = 10 mm for the M2 test, > or = 6 mm for the M5 test and > or = 2 mm for the Rh test. Strongly positive reactions were defined as aP test > or = 10 mm and M2/M5 test > or = 15 mm. One of the tuberculin tests was positive while the comparison test was negative in 14% of the M2 test group (n = 236), 15% in the M5 test group (n = 162) and 20% in the Rh test group (n = 187). The three PPD tests had positive reactions 3-10 times as often, with a simultaneous negative aP test, than vice versa. Strongly positive reactions occurred in 7% of the aP tests (> or = 10 mm), 32% of the M2 tests (> or = 15 mm) and in 41% of the M5 tests (> or = 15 mm). Receiver operating characteristic (ROC) curves gave the best agreement, with aP test >3mm compared with the M2 and the Rh tests. Regression equations are presented for transformations of the Norwegian reference method of adrenaline-Pirquet results to internationally recommended PPD tests. The international recommendations, globalization in general and the skill of Norwegian public health nurses in performing intra-dermal BCG suggest a future shift to the PPD 2 TU Mantoux test in Norway. Due to the lack of sensitivity and specificity of all tuberculin tests they might be used in targeted tuberculin testing and not as a general screening procedure in a low-incidence tuberculosis area with BCG-vaccinated inhabitants.  相似文献   
193.
Introduction: AA amyloidosis develops as a result of prolonged inflammation and is characterized by deposits of N-terminal proteolytic fragments of the acute phase reactant serum amyloid A (SAA). Macrophages are usually found adjacent to amyloid, suggesting their involvement in the formation and/or degradation of the amyloid fibrils. Furthermore, accumulating evidence suggests that lipid membranes accelerate the fibrillation of different amyloid proteins.

Methods: Using an experimental mouse model of AA amyloidosis, we compared the amyloidogenic effect of liposomes and/or amyloid-enhancing factor (AEF). Inflammation was induced by subcutaneous injection of silver nitrate followed by intravenous injection of liposomes and/or AEF to accelerate amyloid formation.

Results: We showed that liposomes accelerate amyloid formation in inflamed mice, but the amyloidogenic effect of liposomes was weaker compared with AEF. Regardless of the induction method, amyloid deposits were mainly found in the marginal zones of the spleen and coincided with the depletion of marginal zone macrophages, while red pulp macrophages and metallophilic marginal zone macrophages proved insensitive to amyloid deposition.

Conclusions: We conclude that increased intracellular lipid content facilitates AA amyloid fibril formation and show that the mouse model of AA amyloidosis is a suitable system for further mechanistic studies.  相似文献   

194.
BACKGROUND/AIMS: Reflux of bile to the oesophagus has been shown to be of importance in the development of gastro-oesophageal reflux disease. This study aims to assess oesophageal motility patterns in relation to acid and bile reflux to the oesophagus. METHODS: Forty-nine subjects with and without reflux disease underwent 24-hour ambulatory recordings of oesophageal pH, bile and 3-channel manometry. Gastroscopy was performed to assess severity of oesophagitis. The percentage of effective peristaltic contractions (oesophageal contractions with a peristaltic pattern and a pressure >30 mm Hg) were correlated to the degree of acid and bile reflux. Ten subjects were re-evaluated within 2 years post-fundoplication. RESULTS: Acid and bile reflux were associated with fewer effective contractions (R(2) = 0.07, p = 0.06 and R(2) = 0.21, p = 0.008, respectively). However, in a multivariate model including acid, bile, age and gender dependency, only bile could show a systematic effect on the variation in percentage of effective peristaltic contractions (R(2) = 0.22, p = 0.001). One year after laparoscopic fundoplication, 24-hour oesophageal motility was unchanged. CONCLUSION: Reflux of duodenal juice to the oesophagus is associated with less effective oesophageal motility, which in turn can perpetuate the disease by less effective oesophageal clearance of bile and acid. The reduced oesophageal motility is not reversed by fundoplication.  相似文献   
195.
Several DNA topoisomerase II (Topo II; EC 5.99.1.3) partial cDNA clones obtained from a human Raji-HN2 cDNA library were sequenced and two classes of nucleotide sequences were found. One member of the first class, SP1, was identical to an internal fragment of human HeLa cell Topo II cDNA described earlier. A member of the second class, SP11, shared extensive nucleotide (75%) and predicted peptide (92%) sequence similarities with the first two-thirds of HeLa Topo II. Each class of cDNAs hybridized to unique, nonoverlapping restriction enzyme fragments of genomic DNA from several human cell lines. Synthetic 24-mer oligonucleotide probes specific for each cDNA class hybridized to 6.5-kilobase mRNAs; furthermore, hybridization of probe specific for one class was not blocked by probe specific for the other. Antibodies raised against a synthetic SP1-encoded dodecapeptide specifically recognized the 170-kDa form of Topo II, while antibodies raised against the corresponding SP11-encoded dodecapeptide, or a second unique SP11-encoded tridecapeptide, selectively recognized the 180-kDa form of Topo II. These data provide genetic and immunochemical evidence for two Topo II isozymes.  相似文献   
196.
STUDY QUESTION: What is the prevalence of respiratory symptoms and obstructive pulmonary disease by age, sex, and smoking history in a population aged 70 years and older? What is the association between selected comorbidities and obstructive pulmonary disease? PATIENTS AND METHODS: A questionnaire on respiratory symptoms and disease, selected comorbidities, and smoking history was mailed to a cross-sectional, sex- and age-stratified, random sample of the population 70 years and older of Bergen, Norway. RESULTS: About 11% of these elderly persons reported having at least one current obstructive pulmonary disease, 8% reported daily wheezing, and 12% reported significant dyspnea. The only respiratory symptom or disorder to show any clear age-related pattern was dyspnea, which increased through age 89 before declining. Dyspnea, current asthma, and current chronic bronchitis were about half as likely in males as females, after adjusting for smoking pack-years. Persons with obstructive pulmonary disease reported problems with walking, heart disease, and muscle/joint disease more frequently than those without. CONCLUSIONS: The prevalence of respiratory symptoms and obstructive pulmonary disease has been estimated. Only dyspnea was associated with age in this elderly population. Female sex was a predictor of dyspnea, current asthma, and current chronic bronchitis.  相似文献   
197.
The plant, Stevia rebaudiana Bertoni (SrB), has been used for the treatment of diabetes in traditional medicine. Previously, we have demonstrated that long-term administration of the glycoside stevioside has insulinotropic, glucagonostatic, anti-hyperglycemic and blood pressure-lowering effects in type 2 diabetic animal models. The aim of this study was to elucidate if long-term administration of rebaudioside A, another glycoside isolated from the plant SrB, could improve glycemic control and lower blood pressure in an animal model of type 2 diabetes. We divided male Goto-Kakizaki (GK) rats into two groups which were fed a standard laboratory chow diet for eight weeks. The diet was supplemented with oral rebaudioside A (0.025 g/kg BW/day) in the experimental group. Blood glucose, weight, blood pressure and food intake were measured weekly. Animals were equipped with an intra-arterial catheter, and at week eight the conscious rats underwent an intra-arterial glucose tolerance test (IAGTT) (2.0 g/kg BW). During the IAGTT, the level of glucose, glucagon, and insulin responses did not differ significantly between the two groups. Fasting levels of glucose, glucagon, insulin or levels of blood lipids did not differ between the groups throughout the study period. We observed no effect on blood pressure or weight development. In conclusion, oral supplementation with rebaudioside A (0.025 g/kg BW/day) for eight weeks did not influence blood pressure or glycemic control in GK rats. Rebaudioside A failed to show the beneficial effects in diabetic animals previously demonstrated for stevioside.  相似文献   
198.
The activity of eosinophils and neutrophils with respect to the release of granule proteins was studied in 11 patients with the hypereosinophilic syndrome (HES). Granulocytes or purified eosinophils were stimulated with serum-opsonized Sephadex particles (C3b-induced release), and the released amounts of eosinophil cationic protein (ECP), eosinophils protein-X (EPX) and myeloperoxidase (MPO) were measured by means of specific radioimmunoassays (RIA). Eosinophils obtained from patients with HES released significantly more ECP ( P <0·002) and EPX ( P <0·01) after 20 min of incubation than cells from the control group. The cellular content of ECP and EPX in eosinophils obtained from the patients with HES was significantly reduced to 50% and 62%, respectively, of the content of these granule proteins of eosinophils from the control group. In separated eosinophils light-density eosinophils released more of both ECP and EPX than normal density eosinophils. There was no difference in MPO release between the patients and the control group. We conclude that the eosinophils from patients with HES have an increased propensity to release their granule proteins and the releasability seems to be related to the density of the cells.  相似文献   
199.
Endocrine pancreatic tumours (EPTs) are uncommon, with a major challenge to alert physicians to their recognition and requirements of treatment. Functioning EPTs cause well-known clinical syndromes of hormone excess. Insulinomas, gastrinomas and glucagonomas are most common; vipomas and somatostatinomas are rare. EPTs also occur as non-functioning lesions without symptoms of hormone excess occasionally with ectopic hormone, such as ACTH and Cushing syndrome as a late complication. The majority of EPTs are sporadic, but they may also be part of a multiple endocrine neoplasia type 1 syndrome or rarely the von Hippel-Lindau syndrome. EPTs have been of great interest to endocrine surgeons and we have, during recent years, witnessed continuing advances in diagnosis, imaging and treatment of the different tumour entities. It has become obvious that surgical treatment of these tumours is of increased concern and can have a marked impact on symptoms and survival.  相似文献   
200.
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