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911.
The dexamethasone suppression test (DST) and response to two different antidepressant drugs (maprotiline as a specific noradrenergic, and amitriptyline as a predominantly serotoninergic drug) were investigated in 44 endogenously depressed female inpatients. The more anxious and/or agitated patients were mostly treated with amtiriptyline, the non-anxious and retarded patients with maprotiline. It was found that among maprotiline responders (N = 15) there were significantly more abnormal DSTs and postdexamethasone serum cortisol levels were significantly higher than among amitriptyline responders (N = 16). On the other hand, DST abnormalities among amitriptyline non-responders (N = 10) were similar to those among maprotiline responders. The results confirm earlier reports by Brown et al. (1980), Ettigi et al. (1983) and Fraser (1983) and indicate that abnormal DST may identify the "noradrenergic" subtype of endogenous depression and that the DST represents a good way of selecting a specific antidepressant drug for the treatment of endogenously depressed patients.  相似文献   
912.
Examination of the input-output events in functioning organs by the use of the impulse-response function (IRF) for a radioactive tracer is gaining more and more ground in nuclear medicine. This study summarizes the development of deconvolution analysis, laying special stress on the model-free approach. System linearity and time invariance are discussed, and means of eliminating noise in IRFs originating from the input and organ-time-activity curves are outlined. Typical IRFs are illustrated by flow diagrams, time-domain curves, and their representation by Laplace transforms. The cases of nondiffusible and diffusible tracers as well as parenchymally extracted and transported substances are discussed. Methods for the derivation of models and for the calculation of physiologically important parameters from theIRFs are suggested.At present, a guest scientist at the Institute for Medicine, Nuclear Research Center Jülich, Jülich, Federal Republic of Germany  相似文献   
913.
A dense osmiophilic structure was found associated to the basal lamina of the outer limiting glial membrane of the carp olfactory bulb. In certain sections this material appears as "beads" composed of small strand-like structures, and in others it seems to form a palisade-like structure. The possible origin and function of this structure is discussed.  相似文献   
914.
The neurological and psychiatric manifestations in a case of Urbach-Wiethe's disease are reported. The present case is characterized by the predominance of cerebral symptoms: ataxia, psychomotoric seizures, paranoic hallucinatory psychosis and attacks of rage. At autopsy, deposits of amyloid-like material in the walls of the brain vessels could be observed. This finding, together with the mucocutaneous alterations, confirmed the diagnosis of the rare disease know as "lipoid proteinosis cutis et mucosae".  相似文献   
915.
The blepharo-periorbitoplasty: anatomical basis   总被引:1,自引:0,他引:1  
A new combined subperiosteal-subcutaneous musculo-aponeurotic system and suborbicularis technique is described: the "blepharo-periorbitoplasty." This technique achieves complete mobilization of the forehead and brow, the lower eyelid, the raphe and lateral canthal area, the upper palpebral region, and of the suprazygomatic and infrazygomatic soft tissues, including the cheeks. These soft tissues are displaced upward and moderately backward. If a major lateral upward slant of the palpebral fissure is desired, Hinderer's lateral canthoplasty must be added. The blepharo-periorbitoplasty technique can be combined with a facial-cervical rhytidectomy. The technique is also useful for senile preectropion and postoperative "round eye" conditions with scleral show. The safety has been proven both clinically and in anatomical dissections.  相似文献   
916.
An in vivo model of liver hyperplastic noduligenesis was inducedin rats by long-term administration of thioacetamide (TAM) (50mg/kg/day i.p.). Three doses of 50 mg/kg of an antitumoral Rh(III)complex were administered at 14, 9 and 5 days before the endof TAM treatment. Plasma and urine were obtained from eitherTAM or Rh(III) complex or TAM plus Rh(III) complex treated ratsto determine the interactions of both substances with the biochemicalparameters related to liver function. The rise in alkaline phosphatase(ALP), teucine aminopeptidase (LAP), -gtutamyl transferase (GGT)and the unchanged activities in the aspartate and alanine aminotransferases(AST, ALT) in plasma of TAM-treated rats indicated that thedisease induced by this substance can be considered as a chronicobstructive biliary disease with indices of cell proliferationand tumors. The increased concentration of bilirubin both inthe plasma and urine of TAM-treated rats suggested liver cholestasisand hepatobiliary obstruction. The very low values of creatinineclearance indicated that there was some degree of kidney failuredue to the effect of TAM. The increased concentration of ammoniaboth in plasma and urine were probably a consequence of thedecreased flux in the urea cycle in the liver. The Rh(III) complexalone did not produce significant changes in the plasma enzymeactivities. The only significant changes were found in the concentrationsof uric acid and ammonia in the urine. When the Rh(III) complexwas administered to TAM-treated rats, significant restorationof the following parameters were observed: plasma enzymaticactivities, blood bilirubin and ammonia, uric acid and creatininein the urine and the creatinine clearance. These results suggestthat the altered liver function induced by TAM can be restoredby Rh(III) complex. The mechanisms by which this complex actsto counteract the TAM-induced changes are not yet established.  相似文献   
917.
We describe the clinical course of 120 children with tricuspid atresia (TA) attended in the Hospital de Cardiología y Neumología, "Dr. Luis Méndez", del Centro Médico Nacional. There were 61 males and 59 females. The age of presentation was in 79 newborn babies, seventeen between one and six months old, 20 between six and 24 months old, and four with two or more years old. The clinical picture was hypoxic spells in 89% and congestive heart failure in the others. The chest film showed cardiomegaly in 85%, with diminished pulmonary flow in 48%, increased flow in 27.5%, and normal in 9%. The electrocardiogram with superior left axis deviation in 94%, right atrial hypertrophy in 58%, left atrial hypertrophy in 47.5% and left ventricular hypertrophy in 96%. TA was classified as type I in 103 children, type Ic in 70, Ib in 27 and Ia in six, and type II in seventeen children, with eight IIc, six IIb and three IIa. In 44 the management was medical, 63 underwent systemic-pulmonary anastomosis, 37 of them with Blalock-Taussig shunt and Fontan procedure in thirteen children. There were 21 deaths. This survey is compared with the literature and from this point we make management recommendations.  相似文献   
918.
The interaction between amphetamine and clonidine on neurotransmission in the rat vas deferens was studied. In the whole vas deferens, clonidine 0.037 mumol/l displaced to the right the frequency-response curve evoked by either hypogastric or field stimulation. The frequency of stimulation that produced 50% of the maximal response (EF 50) was: control 4.0 Hz, clonidine 18.3 Hz (P less than 0.001 n = 4), for hypogastric nerve stimulation; and 2.1 Hz in controls and 17.1 Hz in clonidine-treated preparations, for field stimulation (P less than 0.001 n = 5). Preincubation with 5.4 mumol/l amphetamine antagonized the effect of clonidine (EF 50 amphetamine alone 6.2 Hz, amphetamine + clonidine 7.3 Hz; P greater than 0.5). After 12 min of incubation with clonidine 0.037 mumol/l the responses to 6.4 Hz (3 s, 0.5 ms) were decreased by 77 +/- 2.2%. Both yohimbine and amphetamine, in a concentration-dependent manner, attenuated the inhibition. Washout of clonidine produced a slow recovery of the responses. Inhibition of the motor response to nerve stimulation (6.4 Hz, 3 s) by 30 mumol/l 2',3'-cAMP was increased by 10 mumol/l dipyridamole and impaired by 100 mumol/l theophylline. Amphetamine, in a concentration that markedly reduced clonidine inhibition of neurotransmission failed to antagonize 2',3'-cAMP. In the bisected vas deferens clonidine inhibited the peak motor response to short trains of field stimuli in the prostatic portion ("non-adrenergic") and the sustained response in the epididymal portion ("adrenergic"). Yohimbine potentiated both types of responses and fully prevented the effect of clonidine. In the prostatic portion amphetamine slightly inhibited the peak motor response and attenuated the inhibitory effect of clonidine in both portions of the vas.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
919.
Summary Lower motor neuron degeneration, cerebellar hypoplasia, atrophy of pons, olives, and cerebellum, sclerosis of thalamus and pallidum, and deficient myelination were found in a 2-months-old baby with laryngeal paralysis, mental retardation, progressive amyotrophy, and slow nerve conduction velocity. Such changes seem characteristic of an unusual syndrome previously referred to as cerebellar hypoplasia in Werdnig-Hoffmann disease, or anterior horn cell disease with pontocerebellar hypoplasia. Although the pathologic changes in lower motor neurons are indistinguishable from those in other cases of infantile spinal muscular atrophy, the consistent reproducibility of a complex pathologic pattern suggests that this is probably a manifestation of a separate disease process. The term amyotrophic cerebellar hypoplasia (ACH) is a convenient designation for the syndrome.Supported in part by National Institutes of Health grant no. RR75  相似文献   
920.
Summary Considering the possibility of a paracellular route for edema resolution we studied the microvasculature of the subependymal and subcortical white matter in hydrocephalic rats. Normal adult rats were used as controls. After injection of kaolin suspension into the cisterna magna, the animals were killed at intervals of 1, 2, 4, and 8 weeks. In hydrocephalic rats at 1 week after kaolin injection, widening of the interendothelical cleft between the tight junction (dehiscence) was seen in 27 of 76 (35%) vessels. At 2 weeks after kaolin injection, the number of the dehiscences had increased (39/7:56%) and some were enlarged, forming interendothelial blisters. At 4 weeks in hydrocephalic rats, both dehiscences and blisters were still prominent (45/7363%) and at 8 weeks the dehiscences were still prominent, but the number of the blisters had decreased (25/8131%). The blisters and dehiscences were most pronounced in the corpus callosum and occipital regions. Following i.v. injection of horseradish peroxidase, the interendothelial dehiscences and blisters were completely devoid of the marker substance. These findings indicate that in obstructive hydrocephalus the tight junctions may constitute part of a paracellular pathway for the resorption of interstitial edema fluid.  相似文献   
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