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21.
Flaujeac trait is the functional deficiency of a plasma protein of the intrinsic coagulation, kinin-forming, and plasma fibrinolytic pathways. The Flaujeac factor in man has been isolated and tentatively identified as a kininogen of high molecular weight (HMW). Highly purified bovine HMW-kininogen, but not bovine low molecular weight kininogen, repaired Flaujeac factor deficiency. The two subspecies of this molecule, HMW-kininogen a and HMW-kininogen b, also corrected Flaujeac factor deficiency. When bovine HMW-kininogen was incubated with bovine plasma kallikrein, kinin-free HMW-kininogen, bradykinin, and a glycopeptide fragment (peptide 1-2; 12,584 daltons) were rapidly released. None of these fragmentation products corrected Flaujeac factor deficiency alone or in mixtures. The function of HMW-kininogen appeared to depend upon the structural integrity of the native molecule. When injected in concentrations of 2 pmol-8 nmol/0.1 ml, peptide 1-2 caused increased vascular permeability in rabbits, rats, or guinea pigs. The enhanced permeability was maximal within 1-2 min and terminated in 5-10 min, differing from that of bradykinin or histamine. Injected together in equimolar amounts, peptide 1-2 and bradykinin produced a synergistic permeability response which was immediate in onset as well as prolonged in duration. Peptide 1-2 is a rapidly acting, highly basic glyco-peptide which mediates increased vascular permeability in a complementary and synergistic manner with bradykinin.  相似文献   
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Analysis of the pathological findings in 500 cases of fatal acute myocardial infarction showed that in 469 this was localized to one transmural area of the left ventricle; in 31 there was diffuse subendocardial necrosis. In the former occlusive coronary thrombus was found in the related artery in 95 per cent of cases. Variation in the percentage of occlusions found was noted between different prosectors and when coronary artery calcification was present. Only 4 of the 31 patients with subendocardial necrosis had recent occlusion; triple vessel disease was common in this group suggesting general failure of coronary perfusion. It is essential in necropsy studies of the relation of coronary thrombosis to myocardial infarction to be sure that muscle necrosis is present, to distinguish the two forms of myocardial necrosis, and to employ a meticulous dissection technique with decalcification of the arteries when necessary.  相似文献   
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On the internal or parietal surface of the left ventricle in man and in mammals are two papillary muscles, which are almost identical and well developed. In man, these muscles are known as the m. papillaris parietalis anterior sinister and the m. papillaris parietalis posterior dexter, in mammals, the m. papillaris parietalis cranialis sinister and caudalis dexter, or, in shorter form, mm. papillaris parietalis sinister et dexter. In the right ventricle in man, there are two papillary parietal muscles: the mm. papillares anteriores et posteriores. On the septum of this ventricle there is, as in mammals, a muscle called the m. papillaris septalis medialis seu subarteriosus. Beside it are one or several smaller muscles, varying from one individual to another: the mm. papillares septales accessorii seu parvi. In the right ventricle of the mammalian heart is found, in addition to the m. parietalis septalis subarteriosus, already mentioned, a m. papillaris caudalis, more or less well developed in some species and, in the majority of mammals, the m. papillaris septalis cranials, which is always well developed. In certain mammals, there is, in rare cases, a m. papillaris septomarginalis seu parietalis. It may be said, in conclusion, that, in a large number of mammals, there is, on the internal surface of the external wall of the right ventricle, a reasonably well developed m. papillaris parietalis.  相似文献   
27.
Intraepithelial lymphocyte counts were evaluated in 131 jejunal mucosal biopsies taken from children with a small intestinal enteropathy arising from a variety of causes including coeliac disease, (untreated, after gluten withdrawal, and during subsequent challenge), giardiasis, cow's milk protein intolerance, and 'intractable diarrhoea'. The counts were compared with those from the biopsies of children referred for investigation but in whom no gastrointestinal disease was demonstrated and from healthy siblings of children with coeliac disease, investigated during a family study. Children with coeliac disease showed a raised count which fell after gluten withdrawal as has been demonstrated by others in adults. Lymphocytic infiltration of the epithelium increased rapidly during gluten challenge in such children, while no change was seen in those children proven ultimately not to have coeliac disease by the usually recognized criteria. In other enteropathies the range of counts was wide, overlapping with both normal and coeliac groups and indicating the nonspecificity of lymphocytic infiltration of the gut epithelium. The findings are discussed in relation to their significance and to further avenues of investigation to determine their possible diagnostic value in confirming the diagnosis of coeliac disease during gluten challenge.  相似文献   
28.
The changes of heart rate in response to i.v. administration of methylatropine (0.5 mg/kg) and/or propranolol (2 mg/Kg) or practolol (2.5 mg/Kg) were studied in conscious trained dogs. Cholinergic blockade alone or combined blockade of sympathetic and parasympathetic effector systems resulted in cardiac acceleration. Conversely, beta-adrenoceptor antagonism with either propranolol or practolol reduced heart rate. The data were analysed by means of a new method, whereby the heart (HRN) of the dog is considered to be the product of the intrinsic heart rate (HR0) and 3 further factors: HRN-HR0 times S times V times W (Multiplicative model). 2 of these factors represent the tonic sympathetic (S) and parasympathetic (V) influences, whereas the third (W) represents the sympathetic-parasympathetic interaction. This type of analysis reveals that W was approximately 1, i.e., the sympathetic-parasympathetic interaction did not play any significant role in determining the heart rate of conscious resting dogs (HRN = HRO-S-V-W = HRO-S-V). The change of heart rate due to the action of parasympathetic system (-53% of the intrinsic heart rate) was more important than the change caused by the action of the sympathetic system (26% of the intrinsic heart rate).  相似文献   
29.
Cardiac patients who have undergone 99mTc-stannous pyrophosphate (99mTc-PYP) myocardial imaging can be injected 24 hours later with 99mTc-pertechnetate (99mTc04) to assess left ventricular function. Reduction of 99mTc04 by tin remaining in the blood following the stannous pyrophosphate injection causes labeling of the red cells by 99mTc04 and the creation of a vascular tracer suitable for electrocardiographically gated imaging.  相似文献   
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Seven patients with pulmonary regurgitation (PR), normal pulmonary artery (PA) pressures and large left-to-right atrial shunts are reported. Six had secundum atrial septal defects (ASD) and one had anomalous pulmonary venous drainage. These comprised 4% of 180 patients with atrial shunts and normal PA pressures. Pulmonary regurgitation was diagnosed clinically by mid-frequency diastolic decrescendo murmurs beginning after the pulmonic component of the second heart sound, and diagnoses were confirmed by catheterization. In two patients who had serial preoperative catheterizations over 8 and 16 years, PR progressed in one and was present only on the second study in the other. All patients underwent shunt correction, at which time the pulmonic anulus and artery appeared dilated, but the pulmonic valves were normal and did not require revision. In all patients the PR murmur disappeared after shunt correction alone, and on chest X-ray both PA and overall heart size decreased. Although it is known that pulmonary regurgitation occurs with atrial septal defects and pulmonary hypertension, the present study demonstrates that it also occurs with high flow atrial shunts, in which setting it has different implications and is reversible with shunt correction alone.  相似文献   
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