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991.
A peculiar hereditary corneal disease seen in one pedigree is presented. The disease manifests itself as transient attacks of kerato-endotheliitis. These attacks last from a few days to some weeks. Clinically, corneal oedema and endothelial guttata-like changes with very slight anterior chamber reaction can be seen; after many attacks there may be permanent opacities in the stroma. Endothelial specular photography during an attack reveals dramatic changes: large black nonreflecting areas between quite normal-looking hexagonal cells. Also between the attacks and among family members who have no clinical corneal disease, changes in the endothelium: black spots in the centres of endothelial cells and marked pleomorphism, are to be seen. Among the family members a high incidence of collagen diseases was found.  相似文献   
992.
In 6 patients with medicamentously therapy-refractory tachycardias (3 times auricular flutter/auricular fibrillation with very rapid atrioventricular conduction, once focal atrial tachycardia, once paroxysmal atrioventricular reentry tachycardia, once recurrent ventricular tachycardia on the basis of an interventricular reentry) percutaneous transvenous catheter ablations of the atrioventricular conduction region (bundle of His ablation, 5 cases) and the right Tawara branch (1 case), respectively, were performed. During a follow-up period of 2-26 months (on an average 10.5 +/- 8.0 months) a permanent total block in 4 cases could be obtained (3 times AV-block III. once complete right bundle branch block). In two other patients the total AV block receded to the AV block I. and II. respectively, within 2 and 8 days, respectively; in the first case the AV node reentry tachycardias were no more to be evoked, in the second case a tolerable ventricular frequency was the result during the auricular flutter recidivations. In all patients treated by means of catheter ablation after the intervention an impressive improvement of the clinical symptomatology developed. Due to possible complication and the dependence upon the pacemaker of the patients concerned which is to be expected the indication to the ablation should be made only after the exhaustion of all medicamentous possibilities and taking into consideration other electric therapy methods.  相似文献   
993.
Kinetics of histamine released from rectal mucosa   总被引:1,自引:0,他引:1  
This kinetic study was performed to investigate the different tissue-influencing histamine amounts in Crohn's Disease (CD), Ulcerative Colitis (UC), patients with polyps and cancers (P.a.C.Gr) and in a Control Group (CG). For this purpose the endoscopically obtained specimens from rectal mucosa were immediately placed into 1000 microliters of Hank's incubation medium in order to determine the spontaneously released histamine amounts at the time points of 5, 10, 15, 20 and 30 minutes. Each time a volume of 100 microliters was removed from the incubation medium and the kinetic value (KV) was detected by using the single isotope radioenzymatic method. Influencing of natural histamine catabolism and the comparison of the tissue histamine release with or without air oxygen in the incubation medium using four kinetic programmes (KP1-4) provides clearly different KVs, not only between the KPs but also within the same KP. The P.a.C.Gr. shows higher kinetic values (KVs) compared with the CG. In KP1-3 the kinetic courses (KCs) of the Inflammatory Bowel Diseases (IBDs), CD and UC-both not yet divided in active (a.) or not active (n.a.) disease stages-cross the KCs of the CG several times. Only the differentiation of the IBDs in active and not active disease stages in KP4 reveals that CDa. and UCa. stand out from the CG by higher KVs, and in contrast, CDn.a. and UCn.a. have lower KVs than the CG. The released amounts of histamine in CDa. and UCa. are significantly higher than in CDn.a. and UCn.a.  相似文献   
994.
The influence of alpha-adrenoceptor antagonists on the overflow of endogenous norepinephrine (NE) and vasoconstrictor responses elicited by sympathetic nerve stimulation (1-4 Hz, 2 min) was investigated in desipramine-pretreated canine blood-perfused skeletal muscle in situ. The nonselective alpha-adrenoceptor antagonist phentolamine enhanced stimulation-evoked NE overflow and reduced vasoconstrictor responses concentration-dependently. Similar effects were obtained with phenoxybenzamine (irreversible alpha-adrenoceptor antagonist). Desipramine pretreatment attenuated the enhancement of stimulation-evoked NE overflow produced by phenoxybenzamine, indicating that phenoxybenzamine also inhibits neuronal uptake. The enhancement by phenoxybenzamine was independent of the stimulation frequency, suggesting a similar engagement of prejunctional alpha-adrenoceptor-mediated inhibition of transmitter release over the frequency range studied here. The alpha 2-selective adrenoceptor antagonist yohimbine enhanced nerve stimulation-evoked NE overflow at concentrations similar to those required to antagonize vasoconstrictor responses to exogenous NE; 10-fold higher concentrations were required, however, to antagonize nerve stimulation-induced vasoconstriction. The concept of a quantitatively important prejunctional alpha 2-adrenoceptor-mediated feedback inhibition of NE release in vivo is supported by our findings in the skeletal muscle vasculature. Postjunctional alpha 2-adrenoceptors appear to be preferentially activated by circulating catecholamines but also seem to be involved in the nervous control of vascular tone.  相似文献   
995.
Impaired vagal heart rate control in coronary artery disease.   总被引:1,自引:1,他引:0  
Heart rate variation in deep breathing, a sensitive non-invasive measure of cardiac parasympathetic activity, was measured in 63 patients with coronary artery disease, in 22 patients with atypical chest pain, and in 20 healthy symptom free volunteers. There was significantly less heart rate variation in deep breathing in the patients with coronary artery disease than in the healthy subjects. Twenty patients (32%) with coronary artery disease had lower than normal variation in heart rate. The patients with chest pain showed an intermediate heart rate response to deep breathing. Sinus arrhythmia in the patients with coronary artery disease was not related to the functional class, medication, number or location of narrowed vessels, or to the left ventricular ejection fraction, and end diastolic pressure. These results suggest that impairment of the parasympathetic nervous function is common in coronary artery disease.  相似文献   
996.
Short term cyclosporin A treatment of Beh?et's disease.   总被引:1,自引:1,他引:0       下载免费PDF全文
Eleven separate three-month courses of cyclosporin A, an oral solution 10 mg/kg/day, were administered to eight patients with Behçet''s disease with sight-threatening posterior uveitis. It was found to be effective in arresting the inflammatory activity in the eye as well as the mucocutaneous lesions of Behçet''s disease. Improvement in visual acuity was observed within one week of starting therapy. Severe exacerbations in the ocular and mucocutaneous lesions occurred on withdrawal of the drug. At this dosage side effects included hirsutism in all women, and a slight rise of serum bilirubins in two patients and of blood urea in one patient. The latter two conditions responded rapidly to dose adjustment.  相似文献   
997.
Based on accumulating evidence of the role of xanthine oxidase (XO) in generating oxygen free radicals and causing tissue damage during ischemia, we examined the possible role of XO in the pathogenesis of cerebral vasospasm after subarachnoid hemorrhage (SAH). After inducing SAH in dogs by two autologous blood injections 2 days apart, chronic vasospasm of the basilar artery was reliably produced. There was a 3.5-fold elevation in uric acid (UA), the product of XO, in the cerebrospinal fluid (CSF) of these animals. Parenteral administration of allopurinol (i.v., 25 mg/kg, every 6 hours), a specific blocker of XO, successfully abolished the elevation in CSF uric acid levels due to SAH. However, angiographic vasospasm measured on Day 7, morphological changes observed by electron microscope, and elevated CSF prostaglandin levels were not altered by the treatment. It can be concluded that the observed activation of the enzyme XO, which is a well-known source of oxygen free radicals in ischemia in various organs, is not playing a major role in the pathogenesis of chronic cerebral vasospasm in this animal.  相似文献   
998.
999.
A case of extracranial carotid artery dissection investigated both by conventional brain imaging and by arteriography is presented. The radionuclide angiogram showed a flip-flop phenomenon on the left hemisphere. The implications, including clinical features, pathogenesis, diagnosis, and treatment are discussed. Dissection of extracranial carotid artery is a cause of carotid hypoactivity, and this phenomenon is associated directly with a flip-flop phenomenon on brain imaging.  相似文献   
1000.
The effect of withdrawal of suppressive therapy with thyroid hormones (200 micrograms L-thyroxine/day) on serum biochemical profiles and blood cell counts were studied in ten athyreotic thyroid carcinoma patients. After 14 days off therapy, all patients but one were still clinically and biochemically euthyroid. Twenty-eight days without thyroid hormones resulted in severe clinical and biochemical (TT4, TSH) hypothyroidism. At that time, the following parameters changed significantly: CPK activities increased (in five of ten patients above normal) as well as activities of SGOT, SGPT, and LDH (means and s.d.s within the respective normal ranges). Total cholesterol and triglycerides increased within the normal range. There were minimal but significant increases of serum creatinine and of mean corpuscular volume of erythrocytes as well as decreases of serum sodium and calcium. Our study underlines the importance of further investigation if pathologic biochemical or hematologic parameters are obtained in athyreotic patients after 4 wk withdrawal of thyroid hormone therapy.  相似文献   
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