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891.
892.
Howard Morgan M.D. 《Surgical neurology》1990,33(6):413-416
The Russian writer Dostoevsky (1821–1881) suffered from a rare form of temporal lobe epilepsy termed “ec-static epilepsy.” Dostoevsky used his epileptic experiences to create Prince Myshkin, the protagonist of The Idiot. The recent case of a patient who experienced ecstatic epilepsy as a result of a temporal lobe brain tumor is presented and compared with that of Prince Myshkin. Reading Dostoevsky can give the contemporary physician an insight into the inner life of an epileptic patient — an example of how art can directly benefit medical practice. 相似文献
893.
We have investigated anemia in patients at different stages of the evolution of three chronic renal diseases: Balkan endemic nephropathy (BEN), chronic pyelonephritis (PN) and chronic glomerulonephritis (GN). A total of 88 patients with creatinine clearances from 9 to 118 ml/min and hemoglobin concentrations from 70 to 160 g/l were studied with regard to the relationship, if any, between erythropoietin production and the type and stage of nephropathy. Anemia in BEN was a particular focus of interest since it had been stated that in BEN, anemia precedes renal failure. Our data neither prove nor disprove this statement. A significant positive correlation between creatinine clearance and hemoglobin concentration was found in all three nephropathies, indicating that in the patients studied the severity of anemia increased with the impairment of renal function regardless of the underlying disease. Serum levels of immunoreactive erythropoietin were in the normal range in 54 patients, moderately increased in 20 and slightly decreased in 14. The erythropoietin level appears to be unrelated to the stage of renal failure or the type of nephropathy. The only exception was the subgroup where the patients with glomerulonephritis and normal renal function had increased serum erythropoietin levels and significantly higher parameters of red blood cell concentration than the patients from the same subgroup with tubulointerstitial nephropathies. In patients with severe renal failure and anemia, serum erythropoietin levels were inappropriately low for the degree of anemia, indicating that erythropoietin plays a role in the pathogenesis of the anemia. 相似文献
894.
Monolayer cultures of normal human bone cells contain multiple subpopulations of alkaline phosphatase positive cells 总被引:5,自引:0,他引:5
Toshikatsu Matsuyama K. -H. William Lau Jon E. Wergedal 《Calcified tissue international》1990,47(5):276-283
Summary Cytochemical staining of normal human bone cells in monolayer cultures for alkaline phosphatase (ALP) indicated that the cultures
contained mixed-cell populations. Time course evaluations of the cytochemical staining revealed, in addition to the ALP-negative
cell population, at least two subpopulations of ALP-positive human bone cells with different levels of ALP. A cytochemical
method has been developed which separates the ALP-positive cells into high and intermediate ALP subpopulations. In this method,
human bone cells were stained for ALP using an azo-dye method and incubating at 4°C for 10 and 30 minutes, respectively. We
defined the cell population that stained positively for ALP at 10 minutes as strong ALP-positive cells, and both strong and
intermediate cells were stained at 30 minutes. The intermediate cells were determined from the difference between the values
at the two time points. The intra- and interassay variations of the assay, with the same investigator in blinded investigations,
were both less than 10% and the interobserver variation was approximately 25%. Analysis of the distribution of ALP levels
in cells with a laser densitometer confirmed the presence of at least three cell subpopulations. 1,25(OH)2D3 treatment increased the proportions of both ALP-positive cell populations, whereas TGF-beta treatment increased only the
intermediate ALP-positive cell population. On the contrary, fluoride increased the proportion of the strong ALP cells, and
IGF-1 had no effect on the proportions of either ALP-positive subpopulation. When the ALP-specific activity was compared with
the percentage of each ALP-positive subpopulations for the cells treated with effectors, the ALP-specific activity correlated
with the total ALP-positive and with the strong ALP-positive populations but not with the intermediate ALP-positive subpopulation.
In summary, this study represents the first evidence that normal human bone cells in monolayer cultures contained at least
two subpopulations of ALP-positive cells, and that bone cell effectors could have differential effects on each cell population. 相似文献
895.
Clinical characteristics and surgical treatment of sporadic primary hyperparathyroidism with emphasis on chief cell hyperplasia 总被引:4,自引:0,他引:4
In 570 patients with sporadic primary hyperparathyroidism, the age, sex, symptoms, and preoperative serum calcium values were related to the histopathologic diagnoses, operative findings, and the extent and outcome of parathyroid surgery. Renal stone formation was especially prevalent in younger patients with slight hypercalcemia and parathyroid chief cell hyperplasia, whereas neuromuscular and psychiatric disturbances were overrepresented among older women with higher serum calcium values. Serum calcium concentration was inversely correlated to the proportional incidence of chief cell hyperplasia and positively correlated to the glandular weight of both adenomas and hyperplasias. Glandular size was markedly irregular in chief cell hyperplasia, with increased gland weights of no more than two glands in 78% of patients. During follow-up, for as long as 27 years, normocalcemia was obtained in 91% of patients with adenomas, with failures mainly depending on difficulties in identifying the parathyroid glands. The rate of normocalcemia was lower (80%) among patients with hyperplasia, but an inability to visualize the glands was not a major cause of failure. In patients with hyperplasia with asymmetric and more markedly enlarged glands, it appeared sufficient to remove only the enlarged glands, whereas the findings advocated a subtotal 3- to 3.5-gland resection in patients with more symmetrically or less enlarged hyperplastic glands. 相似文献
896.
1. Effects of a novel imidazoindole derivative on cholinergic function were studied in isolated tissue preparations. 2. The compound demonstrated a dose-dependent (10(-11)-10(-9) potentiation (20-60%) of acetylcholine induced tension in guinea pig ileal tissue. 3. Increases in the size of end-plate potentials and nerve evoked muscle twitches were observed in frog nerve-skeletal muscle preparations. 4. Cholinesterase activity was not inhibited. 5. The results suggest that the compound has actions at the post-synaptic muscarinic receptor complex in smooth muscle and causes pre-synaptic increases in ACh release at the neuromuscular junction. 相似文献
897.
Absorption mechanism and absorption site of a prodrug of L-DOPA, L-3-(3-hydroxy-4-pivaloyloxyphenyl)alanine (NB-355, 1) was investigated using rats. Prodrug 1 (0.5 mM) was taken up by intestinal tissue segments time-dependently in vitro at pH 6.0. However, the rate of uptake was less than that of L-dopa. Inhibitors of the amino acid active transport system (L-Phe, dinitrophenol, ouabain) had no effect on the uptake of prodrug 1. In the intestinal tissue segments, prodrug 1 was extensively hydrolyzed by diisopropylfluorophosphate-sensitive esterase(s). To characterize the absorption site, gastrointestinal tracts were ligated to make acute loops in situ and prodrug 1 or L-dopa was injected into the loops. L-dopa disappeared rapidly from the lumen of the jejunum. In contrast, prodrug 1 disappeared rapidly from the ileum rather than the duodenum or jejunum. From these results, it was suggested that prodrug 1 was slowly absorbed primarily from the lower small intestine. 相似文献
898.
Effects of hypothermia on testicular ischemia 总被引:14,自引:0,他引:14
The ischemic effects of prolonged testicular torsion have been well documented; however, prevention or arrest of the damaging effects of prolonged ischemia has been incompletely studied. Two groups of Sprague-Dawley rats were subjected to varying lengths of bilateral testicular ischemia. Group I underwent normothermic ischemia for two, four, and six hours. Likewise, Group II underwent similar time periods of ischemia, however, after thirty minutes of normothermic ischemia the scrotum of each animal was placed into an ice bath maintained at 4C. Two weeks postoperatively, bilateral orchiectomy was performed. Histology of the testes of the two groups was compared. Neither group revealed significant destruction of the germinal epithelium after two hours of ischemia. Group I revealed only 25% preservation of the germinal epithelium at four hours and only 8% preservation at six hours of ischemia. In contrast, Group II which received ice showed 90% preservation of germinal epithelium at four hours and 85% preservation at six hours of ischemia. We conclude that external ice application significantly preserves seminiferous tubules at four and six hours of ischemic injury in the rat testicle. 相似文献
899.
We report a case of recurrent calculi in a Kock pouch continent urinary diversion. An open operation was avoided by successfully excising the Marlex mesh and removing it with the associated calculi in an endoscopic fashion. 相似文献
900.