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41.
Differentiating seizures from pseudoseizures frequently is challenging in very young children manifesting repetitive, stereotypic behavior. Using video electroencephalographic recording, we evaluated 60 patients, younger than 10 years of age, with episodic signs and symptoms believed to be seizures despite repeatedly normal routine electroencephalograms. Nine patients (15%) had simple partial and atypical absence seizures. Twenty-four patients (40%) had pseudoseizures presenting as rhythmic movements or staring. Pseudoseizure frequency was greater than the frequency of true seizures; brief staring episodes were common. Motor pseudoseizures usually were of longer duration than true seizures and could be brought on with verbal encouragement. Furthermore, the stereotypic motor presentations were quite different from those of true motor seizures but were difficult to recognize from historic, clinical, and routine electroencephalographic data. Symptomatic patients can be clinically diagnosed by analyzing confirmed episodes with video electroencephalography.  相似文献   
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43.
The objectives of this study were: 1) to identify and characterize ewe oviductal secretory proteins (OSP) de novo synthesized during the estrous cycle; 2) to examine the effect of estrogen (E) and progesterone (P) on synthesis of OSP; and 3) to determine synthesis of OSP by ampulla (A) and isthmus (I). Oviducts were collected from cyclic ewes on days 1, 8, and 16 and ovariectomized (OVX) ewes after treatment with corn oil (CO), E, P, and E + P. Tissue was incubated in the presence of 3H-leucine or 3H-glucosamine. Rates of 3H-leucine incorporation into nondialyzable macromolecules by explants was greater (P less than 0.05) on day 1 than days 8 and 16, greater (P = 0.01) in OVX E-treated ewes, greater in A than I regardless of treatment and greater (P less than 0.05) in A than I with E. Culture medium was analyzed by one- and two-dimensional polyacrylamide gel electrophoresis and fluorography. Two major basic proteins (Mr 90-92,000) and three minor proteins were only present on day 1 of estrus. E treatment demonstrated these same proteins which were not found with CO or P treatment. Two-dimensional analysis of medium from A and I cultured separately indicated that A synthesized the two major basic and three minor E-dependent proteins. Of three protein complexes present regardless of treatment or cycle day, two were dominant in the A and one was dominant in the I suggesting a synthetic gradient. Tunicamycin did not inhibit incorporation of 3H-glucosamine into E-dependent proteins. Gel filtration revealed a high Mr fraction (2 x 10(6] 2.5-fold greater on day 1 than day 8 and 2.2-fold greater with E than CO treatment. This study clearly demonstrates: 1) that the oviduct from estrus and E-treated ewes synthesizes two major basic and three minor glycoproteins not detectable on other cycle days or with OVX or P treatment; 2) the E-dependent glycoproteins are synthesized by the A; and 3) a high Mr fraction is induced or amplified by E.  相似文献   
44.
Hepatocytes isolated from the liver of rats after a necrotizing dose of thioacetamide (6.6 mmol/kg) were used to study the postnecrotic process of liver regeneration. Flow cytometry analysis revealed populations of dedifferentiated hepatocytes exhibiting physical properties (size and fluorescence emission at 530 nm) similar to those found in fetal (22 days old) liver cells. The percentage of these cells increased progressively from 24 to 48 and 72 hr after thioacetamide administration. In primary cultures of hepatocytes the effects of phorbol 12-myristate 13-acetate, bombesin and insulin were investigated on the 6-phosphofructo 2-kinase/fructose 2,6 bisphosphate system. Bombesin and insulin stimulated 6-phosphofructo 2-kinase activity and fructose 2,6-bisphosphate content both in control and in thioacetamide-treated hepatocytes. However, phorbol 12-myristate 13-acetate stimulated 6-phosphofructo 2-kinase activity and increased fructose 2,6-bisphosphate concentration in thioacetamide-treated liver cells, whereas no similar response was found in hepatocytes from control rats. The response of postnecrotic thioacetamide-treated hepatocytes to phorbol 12-myristate 13-acetate was similar to that obtained from 22-day-old fetal liver cells, which reveals that different methods might control fructose 2,6-bisphosphate content and therefore the mechanisms of glycolysis and gluconeogenesis at this regulatory step. The lack of response to glucagon of glycogen phosphorylase a and 6-phosphofructo 2-kinase from thioacetamide-treated hepatocytes may indicate that the expression of specific enzymes of carbohydrate metabolism undergoes transitions to less-differentiated isoenzymatic forms. Moreover, the isoenzyme pattern of hexokinases elicits a complete disturbance in glucokinase and hexokinases activities.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
45.
AIM: The aim of this pilot study was an investigation on photodynamic therapy (PDT) whether it is a good alternative for treating periungual and subungual warts of the hands. STUDY DESIGN: Twenty patients (mean age: 30.5 years) with a total of 40 periungual and subungual warts were treated with PDT. A photosensitizer, 20%delta-aminolevulinic acid was applied on the warts. After a mean incubation time of 4.6 h (SD: 1.2), the warts were irradiated with the VersaLight for 5-30 min (15.2 +/- 4.3 min). RESULTS: After a mean of 4.5 treatments a mean clearance of 100% was achieved in 90% of the patients. One patient (5%) showed a clearance of 50% and another showed no improvement. The subungual or periungual location of the wart had no influence on the number of treatments or end result (P > 0.05). There were two recurrences during the mean follow-up period of 5.9 months (SD: 7.6). Besides mainly pain and hyperpigmentation, most treatments had no side-effects. CONCLUSION: PDT can offer a good alternative for treating periungual warts of the hands. Larger studies are indicated.  相似文献   
46.
AIMS: The aims of this observational study were to identify the special needs of children with Type 1 diabetes in schools from the parents' point of view and the difficulties experienced with full integration, and to define a series of interventions which may improve the situation. METHODS: Parents of children aged 3-18 years with Type 1 diabetes were eligible. Those who agreed to participate completed a self-reporting questionnaire which determined the effects of the disease on children, parents and school personnel, and addressed aspects including children's integration, glycaemic control, insulin administration, meals, sports, trips and attitudes of teachers and school colleagues to their disease. RESULTS: A total of 499 questionnaires were completed and validated. Median age of children was 11.5 years (95% CI 7.8-15.2). Only 34% of parents believed that teachers could recognize the symptoms of a mild hypoglycaemic episode. Seventeen per cent of parents experienced problems at their schools when they informed staff about their children's disease, 5% were finally not accepted and 8% were forced to change school. In some cases, they had to modify glucose monitoring (9%) and treatment administration (16%) because of a lack of cooperation from the school. CONCLUSIONS: Training sessions on Type 1 diabetes, an increase in the number of nurses, better availability of resources from diabetic associations to schools and improved communication between school personnel and parents were identified as key factors that may improve the full integration of the diabetic child in this setting.  相似文献   
47.
N C Inestrosa  J Alvarez 《Brain research》1988,441(1-2):331-338
Caliber and microtubular density of myelinated fibers, acetylcholinesterase (AChE) content and its accumulation at a ligature were studied in the phrenic nerve of mature (3-4 months) and aging (2-year-old) rats. The number of axons remained constant. The cross-sectional area of the nerve was 67% greater in the older group; the axoplasm, though, constituted about 20% of the nerve tissue irrespective of age. The mean cross-sectional area of myelinated axons was twice as big in aging compared to mature rats. All axons grew in the same proportion irrespective of their original caliber. The microtubular density of 3-microns axons was about 22 microtubules/micron2 in mature and aging rats. The AChE activity of aging rats was half as much as that of mature rats if it was expressed per wet weight of nerve tissue but did not change if it was expressed per nerve fiber. Twenty-four hours after ligation of the nerve, total AChE activity rose in mature and aging rats by ca. 168%; the molecular forms--asymmetric and globular--accumulated in the same proportion in both age groups. We conclude that myelinated axons grow in the adult stage of life but the structure of axoplasm, content of AChE per axon, and rate of fast transport remain lifelong features of nerve fibers.  相似文献   
48.
The effects were studied of a toxin (Bainh) isolated from the secretion of the Caribbean sea anemone Bunodosoma granulifera on electrical and mechanical activities of rat ventricular muscle. The effects on the ionic currents of single rat and dog ventricular cardiomyocytes were studied using the whole-cell recording patch-clamp technique. In the concentration range from 1 to 10 mg/ml, Bainh increased the force of contraction and induced an increase in action potential duration of ventricular multicellular preparations. In single cardiomyocytes, at concentrations up to 10 mg/ml Bainh showed no significant effects on the sodium current. However, at 0.5–1 mg/ml it increased the L-type Ca current (ICaL) by 25–50%. This increase in ICaL was not voltage dependent and was reversible after washout. The transient outward current was not significantly affected by Bainh (1–10 mg/ml). In this concentration range, Bainh markedly (≈75%) increased the inward-going rectifier current, IK1. This effect that was not voltage dependent and was fully reversible upon returning to control solution. It is suggested that these effects on ionic currents could explain the positive inotropic action of Bainh on cardiac multicellular preparations.  相似文献   
49.
Myoclonic movements have been observed in depressed patients receiving therapeutic doses of clomipramine. Such movements, which appear in states of deep muscular relaxation such as sleep, do not appear to have any repercussion in the outcome of the depression and are reversible following withdrawal of the drug. In this study the plasma levels of clomipramine and desmethylclomipramine were determined and their possible relationship with myoclonus studied. No statistically significant relationships were found.  相似文献   
50.
This paper examines various devices used in strength building exercise programs. These include free weights, pulley machines, variable resistance weight machines, isokinetic units and elastic tubing and banding. Advantages and disadvantages of each are discussed and examined from the view point of the health care provider and the suitability of each type of device for prescribed progressive resistance exercise programs for patients. In addition to such practical aspects such as cost and maintenance, biomechanical factors, types of contraction elicited, ease of patient instruction and proprioception benefits are also compared in order to assist the clinician in selecting the most appropriate equipment for each individual patient.  相似文献   
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