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991.
In fetal rats whose dams were fed a low-protein diet, 35S sulfate uptake into the growth plate of the long bone and rib was higher than in the control group. The elution pattern of guanidine-HCl extract in gel chromatography revealed that the malnourished group had more high molecular weight proteoglycans in the dissociative condition and a larger aggregated portion in the associative condition than did the control group; however, the same chondroitin-sulfate chain size existed. Calcium content did not differ in both groups. Aggregated proteoglycan or a high molecular weight proteoglycan that existed in the malnourished group probably played an inhibitory role in calcification. Prenatal protein-energy malnutrition may delay the change of proteoglycan character, which could affect mineralization of fetal bones.  相似文献   
992.
The role of hemoglobin in arterial narrowing after subarachnoid hemorrhage   总被引:3,自引:0,他引:3  
A porcine model for subarachnoid hemorrhage has been developed to allow the selective application of blood and its components to cerebral arteries. Whole blood was centrifuged to produce two fractions consisting of washed erythrocytes (red blood cells, RBC's) and white blood cells (WBC) plus platelet-rich plasma (PRP); the RBC fraction was subsequently separated into hemoglobin (Hb)-containing cytosol and erythrocyte membranes. Each fraction was selectively applied to the middle cerebral artery (MCA) of pigs for 10 days; after which, vessels were perfusion-fixed and examined by light and transmission electron microscopy and immunohistochemical studies. By morphometric analysis, a marked reduction in the MCA lumen cross-sectional area was observed after selective application of RBC's or Hb/cytosol but not of WBC/PRP or erythrocyte membranes. In both RBC- and Hb/cytosol-treated vessels, luminal narrowing was associated with a differential increase in vessel wall thickness of the ventral (subarachnoid) compared to the dorsal (brain) aspect of the artery, but no significant change in cross-sectional area of the vessel wall. After 10 days of exposure to RBC's or Hb/cytosol, there was a spectrum of ultrastructural changes in the vessel wall comparable to those seen after periadventitial application of whole blood. Selective application of commercially available Hb to MCA produced similar structural and morphometric changes. The degree of luminal narrowing after exposure to whole blood or RBC's was proportional to the volume of the erythrocyte mass adjacent to the vessel at sacrifice. These data suggest that arterial narrowing after SAH is mediated by mechanisms related to prolonged exposure of the vessel wall to hemoglobin or its catabolites from lysing subarachnoid erythrocytes.  相似文献   
993.
Certain features of head-injured patients admitted to the Chang Gung Memorial Hospital in Taiwan during the period 1977 to 1987 were reviewed. The most common causes of injury were motorcycle accidents (56.3%) and street accidents with pedestrian injury (29.47%). The age groups with the greatest incidence of injury were aged 16-20 years, 21-25 years, and 25-30 years. The pedestrian group involving the highest incidence of injury was less than 10 years of age. Overall mortality was 17.26%. The injured pedestrian group had the highest mortality (19.1%). Initial clinical assessment was recorded using the Glasgow Coma Scale. Head-injured patients with a GCS less than 8 had a mortality in the injured pedestrian group of 46%, whereas the mortality rate in the motorcycle accident group was 41%. Additional features studied were time of occurrence of injury and pattern of injury. Information gathered from this study would suggest the need to establish a Head Injury Prevention Program in Taiwan. This of course implies major cooperation among the providers of health care delivery, the medical profession, legislators, and the government at all levels.  相似文献   
994.
Seventy-three fractures of the femoral shaft (seventy patients) were randomized to treatment with interlocked nailing with either the Brooker-Wills femoral nail (thirty-nine fractures) or the Russell-Taylor femoral nail (thirty-four fractures). Sixty-one patients (sixty-four fractures) were prospectively followed from admission until healing of the fracture. Specific attention was paid to recording operative details, including technical difficulties associated with insertion of the nails. Technical difficulties were encountered in insertion of the proximal screw, distal screw, and nail, and in deployment of the fins. Insertion of the Russell-Taylor nail was associated with less technical difficulty, operative time, and estimated loss of blood. The two nails differ in their biomechanical properties, methods of fixation, and instrumentation. These differences did not affect the clinical outcome; the fractures in both groups of patients healed with excellent functional results.  相似文献   
995.
The principles of treatment of tibial pseudoarthroses complicated by skin and soft tissue loss with the use of cancellous bone grafts from posterolateral approach to the tibia by Harmon method were discussed. The detailed surgical technique was presented. Management of 3 patients that resulted in bone union was described.  相似文献   
996.
Activation of an endogenous opioid system has been associated with an elevation in pain threshold during late pregnancy and the early postpartum period in rats. It is well established that endogenous opiates are involved in the physiological regulation on prolactin secretion. This study examined the influence of lactation on pregnancy-induced analgesia during the early postpartum period in rats. Three tests (colorectal distension, tail-flick and hot-plate) were used to assess each animal's response to painful stimuli. After determining pregnant baseline values, one group of rats (lactating, n = 21) were mated and retested on Day 7 and 21 of gestation and 1, 3, 5, 7 and 14 days after parturition. A non-lactating group of animals (n = 14) whose pups were removed immediately after delivery was tested in the same manner. On Day 21 of gestation significantly higher thresholds and longer latencies were observed. On Day 1 and 3 in both lactating and non-lactating rats, the values were still elevated. No significant difference was observed during the early postpartum period between the two groups. This study confirms the existence, in rats, of pregnancy-induced analgesia late in pregnancy and the early postpartum period. The analgesia during the early postpartum period is not influenced by lactation.  相似文献   
997.
Summary The effect of haemodialysis on the pharmacokinetics of oral famotidine has been studied in five elderly anuric patients. Famotidine 20 mg was administered in a cross-over design to patients on and not on haemodialysis.The elimination rate constant of haemodialysis (k) was 4.6-fold larger than the systemic elimination rate constant (ke). Although the mean maximum serum concentration of famotidine during haemodialysis (141.5 ng·ml–1) was not significantly lower than that without haemodialysis (195.6 ng·ml–1), the AUC up to 5 h during haemodialysis was significantly decreased to 58.1% of the value without it.The data suggest that famotidine is dialysable by haemodialysis.  相似文献   
998.
Records of 34 children diagnosed as having Kawasaki disease in the Auckland region from 1979 to 1988 inclusive were reviewed. Diagnostic and associated features were similar to those reported from North America and Japan. The incidence (average 5.1 per year per 100,000 less than 5 years of age) was similar to that reported in Europe and North America amongst nonorientals and was similar in Polynesians and nonPolynesians. Coronary artery abnormalities were found in five cases (15%), and two cases, both of whom presented before five months of age, died. Those with abnormal coronary arteries had fever for a significantly longer period than those with normal coronary arteries.  相似文献   
999.
1. The time courses of the relaxation, induced by removal of extracellular Ca2+, of K-depolarized mesenteric artery preparations from stroke prone spontaneously hypertensive rats (SHRSP) and Wistar-Kyoto rats (WKY) were compared. 2. The time course of the decline in extracellular Ca2+ was estimated from the time course of the relaxation and the concentration-response curve of K(+)-depolarized preparations to Ca2+. The time course of the decline in the intracellular free Ca2+ concentration was also estimated from the reported relation between Ca2+ concentration and the contraction of skinned vascular smooth muscle. 3. The time course of relaxation was exponential, the curve being made up of three components. The time course was slower in preparations from SHRSP, especially the first component of the relaxation curve. 4. The time courses of the decline in the intracellular and extracellular Ca2+ concentrations were also exponential, being made up of three components and were also slower in the preparation made from SHRSP. 5. The wall and muscle layer of the mesenteric arteries used in the present experiments were significantly thicker in the SHRSP preparations. 6. Calculation of the half relaxation time, based on the diffusion of Ca2+ across the blood vessel wall, suggested that the slower relaxation in preparations from SHRSP is due largely to the thicker muscle layer, although differences in Ca2+ sequestration by the smooth muscle cells may also be involved.  相似文献   
1000.
This study demonstrates by a virologic culture method that human immunodeficiency virus (HIV) resides in bone. After freezing, some initially positive specimens no longer yielded virus, but those that continued to yield virus were not further altered by subsequent washing, which removed essentially all marrow, or by freeze-drying. The safeguards against potential transmission of HIV by a bone allograft are principally the screening and testing methods previously described, although there may be a further reduction of the remote residual risk by the freezing step in the usual technical sequence for tissue banking by sterile techniques.  相似文献   
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