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1.
Hyperreflexia is the most common urological finding in patients with multiple sclerosis. A prospective randomized study was done to compare the effectiveness of 2 commonly used drugs, oxybutynin and propantheline. Of the 34 patients entered into the trial 19 were treated with oxybutynin and 15 with propantheline. The urological symptoms (frequency, nocturia, hesitancy, urgency and urge incontinence) were graded according to severity from 0 to 3. Patients with urinary infection were excluded. Urodynamic examination, consisting of cystometrography and electromyography, was performed in all patients before treatment. Both groups of patients had comparable neurological, urological and urodynamic status before treatment. In 4 patients (21 per cent) treated with oxybutynin and in 4 (27 per cent) treated with propantheline side effects were so severe that the treatment had to be discontinued. Symptomatic response to oxybutynin was good in 10 patients (67 per cent), fair in 2 (13 per cent) and poor in 3 (20 per cent). Propantheline produced good symptomatic results in 4 patients (36 per cent), fair in 1 (9 per cent) and poor in 6 (55 per cent). The mean increase in maximum cystometric capacity on cystometrography was significantly larger in the oxybutynin group than in the propantheline group (144 +/- 115 versus 35 +/- 101). Our results indicate that oxybutynin is more effective than propantheline in the treatment of detrusor hyperreflexia in patients with multiple sclerosis.  相似文献   
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We investigated the contribution of mechanical and sympathetic neural factors to proximal urethral sphincter dysfunction in the cat after chronic sacral rhizotomy. Concomitant vesicostomy prevented a decrease in the urethral pressure profile measured three months post-rhizotomy. Sympathetic influences on basal urethral perfusion pressure were the same in neurally-intact and chronic rhizotomised cats. A significant prazosin-sensitive component of basal urethral perfusion pressure remained after section of all extrinsic urethral innervation in both neurally-intact and chronic cats. Local intra-arterial 6-hydroxydopamine also abolished this component. After rhizotomy, noradrenaline content in the proximal urethra was significantly increased but there was no change in sensitivity to sympathetic stimulation. A small (5% of control) atropine-sensitive and prazosin-resistant constriction was seen only after chronic sacral rhizotomy. We conclude that a mechanical factor associated with bladder expression and not an alteration in sympathetic control is the major factor leading to diminished proximal urethral closure after vesicourethral lower motor neuron lesion. Furthermore, short adrenergic neurons have an important role in the maintenance of urethral pressure in the normal state and after lower motor neuron lesion.  相似文献   
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Purpose  

The aim of this study was to investigate current prescribing and dispensing practices at primary healthcare centers in Kuwait and compare them with those reported in other countries.  相似文献   
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Occult congenital temporal lobe encephalocele has rarely been reported in association with medically intractable complex partial seizures. The four previously reported cases were unsuspected preoperatively. We present the case of an 18-year-old woman with intractable complex partial seizures since age 13. Seizure onset was electrically localized to the right temporal lobe. Preoperative neuroimaging studies revealed a middle fossa defect and inferior herniation of the right temporal lobe. Pathologic examination of the resected encephalocele revealed prominent features of meningoangiomatosis. We believe this to be the first case of temporal lobe encephalocele and epilepsy to be diagnosed preoperatively, and the first case also to be associated with meningoangiomatosis. The relevant literature on meningoangiomatosis and on temporal lobe encephalocele as a cause of epilepsy is reviewed.  相似文献   
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The ultrastructure of the avian Golgi tendon organ (GTO) is described and compared with those of mammals using transverse sections through the myo-tendinous junctions of wing muscles of adult mallard ducks. The capsule, which is continuous with the perineural epithelial sheath of the Ib afferent nerve fiber, consists of four to seven flattened cellular lamellae. Two to four muscle fibers attach to large collagen bundles which enter the GTO through a tight collar at the proximal end of the fusiform capsule. These collagen bundles divide into many smaller bundles, which run longitudinally through the lumen in compartments formed by septal cells. The septal cells contain many prominent lipid accumulations. The Ib axon divides several times, and the unmyelinated branch axons weave between the small collagen bundles. Schwann cell processes or basement membrane usually intervene between the axons and collagen bundles. The small collagen bundles regroup into larger bundles, which pass through tight capsular collars and merge with the main muscle tendon. The size of the duck GTOs was measured and found to be smaller than the GTOs of man, cat or rat.  相似文献   
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Breast and ovarian cancer rates in Pakistan are significantly higher than in neighboring countries. The cancer rate discrepancies cannot be explained with discrepancies of their risk factors. We propose that observed cancer excess in Pakistan is due to cancer development by negative heterosis. Heterosis occurs when a hybrid has a phenotypic characteristic significantly different from that in either parent (hybrid vigor). At a molecular level, heterosis occurs in a heterozygote when one of the two alleles is inactivated. Gene inactivation occurs by methylation of cytosine in a promoter region of a gene. Initiation of allele inactivation is linked to the factors like stress, gender, diet, or another gene. In heterozygote, inactivation of one of the two tumor-suppressor alleles leads to monoallelic expression. This increases cancer risk in the same way the risk is increased in individual who inherit a single mutated tumor-suppressor gene (hereditary cancer syndrome). In both, cancer by heterosis and inherited cancer syndrome, cancer develops after inactivation of a second allele (second hit hypothesis). In a population, conditions that favor development of cancer by heterosis are those that favor mating of a large number of different homozygotes because they produce a large number of different heterozygotes. Among a large number of heterozygotes, there is an increased chance that some of hybrids will develop cancer by heterosis. In Pakistan, conditions were favorable for cancer development by heterosis because country has a high number of different ethnic groups and brotherhoods all of which have a higher rate of homozygosity due to a high frequency of consanguineous marriages, and marriages between members of different groups occurred because of intense population mixing. Result was birth of a large number of inter-ethnic/brotherhood hybrids (heterozygotes), some of which have developed cancer by heterosis.  相似文献   
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