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991.
Synthetic chromogenic substrates were adapted to KEM-O-MAT 2HP for an automated monitoring of anticoagulant treatments, determination of factor X (S 2337) in oral anticoagulation, anti-Xa (Hepachrom) and anti-lla (S 2238) activities of heparin in prophylactic and curative heparin therapies. In all cases, these methods revealed high sensitivity, reproducibility, and a good correlation of their results with those of classical clotting assays. The present cost of synthetic substrates seriously limits the potential value of chromogenic assays for routine controls. However, the development of automated amidolytic techniques should provide an easier standardization in the laboratory control of anticoagulant treatments.  相似文献   
992.
Three cases of metastatic basal-cell carcinoma are reported. All of the cases were relatively small when compared with other lesions reported in the literature. With early chemosurgical treatment of small recurrent carcinomas, metastasizing basal-cell carcinoma will be a condition of the past.  相似文献   
993.
Increased child abuse in families with twins   总被引:1,自引:0,他引:1  
Close spacing of children may be a significant risk factor for subsequent abuse in some families. Twin births are an extreme example of close spacing. Therefore, the authors hypothesized that twin births may predispose to an increased incidence of child abuse. Thirty-eight families with twins were compared with 97 single birth families and matched for birthdate, maternal age, race, and socioeconomic status. Families with twins experienced a significantly higher incidence of child abuse and neglect than did those with single births (p less than .003). A written questionnaire designed to study mothers' feelings and perceptions of support systems showed a significant difference only in greater difficulty in feeding twins as compared with single infants (p less than .001). Mothers of abused children were more likely not to answer the questionnaire at all (p less than .005). Neither mothers of single births nor those of twins felt that health professionals provided adequate education or support following the birth of their infants.  相似文献   
994.
Pheochromocytoma     
We present a series of 11 patients with pheochromozytomas. We recommend screening for a catecholamine-producing tumor for every patient with hypertension. Screening and diagnosis are based on demonstration of an increased catecholamine production or -excretion. In our laboratory determination of urinary vanillin-mandelic-acid proved to be quite accurate. As 6 of our 11 pheochromozytomas were found extra-adrenally preoperative evaluation with regard to localization of these tumors appears as sound practice. According to our experience no single examination can be favoured. Therefore localization of these tumors is best accomplished by multiple diagnostic procedures. Morbidity and mortality depend directly upon preoperative recognition of a catecholamine-producing tumor and thus according management. We were able to gather data on 8 of 10 surviving patients 4--13 years postoperatively. Six of these are normotensive without any treatment.  相似文献   
995.
996.
The experimental evidence relating ST segment elevation in the electrocardiogram to the progress and extent of ischaemic myocardial damage is discussed. There are difficulties in applying this to patients: the reproducibility of praecordial mapping was tested using a multiple analysis of variance. This showed that factors such as time after the onset of myocardial infarction and posture can affect measurements of sigmaST elevation significantly. There was a pattern of changes in segmaST elevation and of changes in plasma MB CK activity in a group of patients with uncomplicated anterior infarction. A significant byt weak correlation was found between sigmaST elevation in the first hour and the total MB CK activity released into the plasma, but not at any other time. The use of sigmaST elevation as a measure of the extent of ischaemic damage is unreliable. In 5 patients with a variety of complications of acute anterior infarction, changes in sigmaST elevation werr significantly different from the uncomplicated group, and MB CK release profiles suggested further necrosis. The pattern and time course of ST segment changes may be of use in assessing the progress of ischaemic myocardial damage.  相似文献   
997.
This study establishes the viscoelastic nature of the human chorioamniotic membrane. Membrane tissue taken from term pregnancies was placed in a state of biaxial stress consistent with the condition in which membranes rupture in normal healthy patients. The phenomena of creep, stress relaxation, elastic recovery, and time-dependent load deformation relations were demonstrated. The experiments needed to produce these phenomena are described. The results are graphically reported. The experiments were performed using samples of fetal membranes and compared to gum rubber which is a known elastic material. From the results, one can conclude that fetal membranes are viscoelastic. The flow freely under applied stress, and they have elastic and viscous properties which are time dependent.  相似文献   
998.
The uni-arterial vascularisation of the lateral bilary duct makes it impossible to systematise the arteries which supply the common bile duct. Only the cystic artery is seen at coelio-mesenteric catheterization. The techniques essential for visualisation of the cystic artery are discussed, on the basis of one hundred coelio-mesenteric arteriograms: frequency of demonstration, origin, course, termination, calibre and length. The frequent finding of opacification of the wall of the gall bladder under normal conditions is stressed.  相似文献   
999.
1000.
Elevated circulating levels of immunoreactive parathyroid hormone (PTH), hypercalciuria and renal calculi were found in 3 patients with distal renal tubular acidosis (RTA). Treatment with alkali resulted in a fall of PTH toward normal and a reduction in urinary calcium, but the frequency of urolithiasis was unchanged. In one patient in whom prolonged follow-up was possible, a subtotal parathyroidectomy was performed. This was followed by virtual cessation of stone formation despite persistence of the acidification defect. This study suggests that RTA may be associated with secondary hyperparathyroidism and that the consequent elevation in PTH may play a contributory role in the pathogenesis of renal calculi.  相似文献   
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