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931.
Neutrophil production and distribution were studied in two families with autosomal dominantly inherited neutropenia to distinguish their illness from other neutropenic disorders. In addition to a reduced post-mitotic pool of bone-marrow neutrophils and neutrophil precursors, mitotic pool size was also reduced, ranging from 1.1 to 2.9 X 10(9) cells per kilogram (normal, 3.8 +/- 0.4 X 10(9) per kilogram). In vitro committed stem cells were reduced as well, ranging from 2 to 12/10(5) marrow cells (normal, 30 to 120/10(5)). In three patients neutrophil counts were observed to return to normal when they were adults. In one such subject studied, however, both the mitotic pool of neutrophil precursors and marrow committed stem cells were reduced. These abnormalities were in contrast to studies of a patient with chronic benign neutropenia of childhood and an infant with Kostmann-type congenital neutropenia, both of whom had increased marrow committed stem cells. These studies demonstrate several different mechanisms for production of neutropenia in these syndromes.  相似文献   
932.
933.
A 45-year-old man underwent a jejunoileal shunt procedure for obesity. Twenty months later he developed severe oxalosis and chronic renal failure, which required maintenance hemodialysis. The sequential observation of two biopsy specimens and the necropsy (over a span of 39 months) suggests that oxalate deposition caused tubular obstruction and destruction with subsequent atrophy of nephrons. This indicates that patients undergoing intestinal bypass are at risk for developing irreversible renal failure due to enteric hyperoxaluria.  相似文献   
934.
The activities of delta-aminolevulinic acid (ALA) synthetase and ALA dehydratase in cord blood erythrocytes of newborn infants and peripheral blood red cells of patients with beta-thalassemia major, beta-thalassemia intermedia, hemoglobin K?ln (Hb K?ln) disease, sickle cell anemia, and pyruvate kinase deficiency were studied. The activity of ALA dehydratase did not vary appreciably with the number of immature RBC (reticulocytes and nucleated red blood cells) or the severity of the hemolytic anemia except in pyruvate kinase deficiency. The activity of ALA synthetase was linearly correlated with the number of immature RBC (r=0.974, p is less than 0.001). The ALA synthetase activity was significantly decreased in the RBC of Hb K?ln (p is less than 0.01) when compared with the activity in immature RBC of newborns and of patients with pyruvate kinase deficiency, sickle cell anemia, and thalassemia intermedia.  相似文献   
935.
Radioimmunoassay of thyroxine and triiodothyronine in a 14-year-old girl with primary hypothyroidism and nodular goitre as a result of Hashimoto's thyroiditis gave falsely low values due to the presence of hormone-binding antibodies. Such antibodies occur in Hashimoto's thyroiditis and thyroid carcinoma. Their presence requires special methods for determining these hormones.  相似文献   
936.
An apparatus is described for rigid suspension of the spinal columns of mammals ranging in size from large dogs to small rabbits. This apparatus is unique in that the animal is suspended on its side, allowing free access to the entire spinal column for spinal cord studies and free access to the thoracic and abdominal regions for heart, lung, and visceral studies that may require simultaneous surgical procedures in both ventral and dorsal regions.  相似文献   
937.
Effect of magnesium and polyamines on the structure of yeast tRNAPhe   总被引:1,自引:0,他引:1  
The action of sodium azide on the electron transport chain was investigated by means of oxygen evolution, fluorescence and luminescence measurements. (1) The damping of the oxygen oscillations is progressively reduced with increasing azide concentration in the range of 10(-5) - 10(-1) M. (2) The rate of the dark decay of the S2 and S3 states is considerably slowed. The degree of slowing is dependent on concentration. (3) Luminescence is inhibited by azide both in the presence and absence of 3-(3,4-dichlorophenyl)-1,1-dimethylurea (DCMU). (4) The fluorescence induction curve in strong light is modified in the presence of azide and its shape depends on azide concentration and on incubation time. (5) At a given time after a saturating flash, the fluorescence yield in the presence of azide is much higher than that of the control. It seems to be due to a general fluorescence increase rather than to a slower Q- reduction. (6) We tentatively propose an accelerated reduction of the primary donor P+ in state S2 and S3, by the intermediate donor Z in the presence of azide. Additionally, we have to assume that in the S2 and S3 states, some centers are blocked in an inactive low fluorescent form and that azide decreases their concentration.  相似文献   
938.
939.
Hypertension and renal disease in systemic lupus erythematosus   总被引:1,自引:0,他引:1  
A retrospective analysis of 235 patients at the National Institutes of Health who met at least five criteria for systemic lupus erythematosus (SLE) indicated that 45% were hypertensive. Approximately two thirds of these hypertensive patients had creatinine clearances of more than 60 ml/min and nonnephrotic range proteinuria. Only 16% of normotensive patients had creatinine clearances of less than 60 ml/m9n. A subgroup of 36 patients with SLE and with biopsy-proved diffuse renal disease were studied. For these patients, the presence of hypertension could not be correlated with the degree of proteinuria or hematuria, with the level of serum complement, or with the presence of casts, focal necrosis, crescent formation, or interstitial inflammation. Hypertensive patients had a median age of 24.5 years; the majority had creatinine clearances of more than 60 ml/min. In SLE, hypertension is not necessarily associated with advanced renal disease, and high blood pressure may occur relatively early in the course of the disease.  相似文献   
940.
Two cases of nipples placed too high by reduction mammaplasties have been corrected by a combination of maneuvers--including (1) shortening the distance from the nipple to the inframammary line, and (2) repositioning of the areola-nipple component or putting in an implant to make the main projection of the breast directly behind the nipple.  相似文献   
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