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101.
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Muscle strips from the fundus, trigonum and distal ureters obtained from children at operations for vesico-ureteric reflux were studied using histochemical and immunohistochemical methods, and electrical nerve stimulation in an organ bath. A rich supply of cholinergic nerves was found and despite a partial atropine resistance the neurophysiological experiments indicated that the transmitter causing contraction of the detrusor muscle is acetylcholine. Imipramine, which is used in the treatment of enuresis, had no anticholinergic effect on the bladder in the doses used clinically. The adrenergic innervation was very sparse except around the ureter orifices. No contractile alpha-adrenoceptors could be detected but beta receptor mediated relaxation was found, which was neither of the beta 1 nor beta 2 type. A third type of beta receptor is postulated. Peptidergic nerves containing vasoactive intestinal peptide, VIP, were demonstrated in a few nerve terminals running along bundles of smooth muscle. No nerves containing enkephaline, somatostatine or substance P were found. VIP affected the detrusor muscle indicating a possible role as a modulator of transmitter action, while substance P had no effect. The anticholinergic and calcium antagonistic drug terodiline inhibited all muscle activity, whether it was induced by nerve stimulation, cholinergic drugs or a potassium rich solution, making it suitable for treatment of diurnal enuresis.  相似文献   
103.
We identified 15 patients (63 +/- 8 years) in whom CT showed no bleeding within 6 hours of stroke onset but showed ganglionic or lobar hemorrhage less than 18 hours later, without visible underlying infarct (early spontaneous intra-infarct hematoma [ESIH]). No patient had antithrombotic therapy or a coagulation disorder, but eight had hypertension. The second CT was prompted by rapid worsening (in 10) or because the first CT was not available (in five). Prior transient ischemic attacks, silent infarcts on CT, and a potential cardiac source of embolism were more common in patients with ESIH than in 200 patients with primary cerebral hemorrhage (PCH) admitted during the same period. Distal occlusions were present in four of five patients who underwent intracranial studies within the first 2 days. Most of these patients probably had embolism with early and extensive bleeding in the ischemic area. Our findings suggest that ESIH may be under-recognized, while PCH may be overdiagnosed.  相似文献   
104.
Magnetic resonance imaging (MRI) of the oropharyngeal region from 20 adult volunteers using four model inhalation devices (varying mouthpiece diameters, airflow resistances) and tidal breathing was carried out. Statistical analysis (convex hull method) selected 12 scans from 80 data sets representing the extremes of all dimensions in the population. Twelve physical mouth-throat models were made by stereolithography using the exact scan data. The aim was to produce models with varying dimensions to span the adult population, and to investigate if oropharyngeal dimensions affected throat retention for different delivery systems. In an in vitro analysis, the models were used to determine the retention effect of the oropharyngeal airspaces when drug aerosols were administered from four inhalation delivery systems: a pressurised metered dose inhaler (pMDI), two different dry powder inhalers (DPIs A and B), and a nebulizer. The aims of this work were to determine the key parameters governing mouth-throat retention and whether retention was dependent on the delivery system used. Characterizing the throat models by measuring 51 different dimensional variables enabled determination of the most influential variables for dose retention for each inhalation delivery system. Throat model retention was found to be dependent on the delivery system (pMDI approximately DPI(A) > DPI(B) > Neb.). The most influential variable was the total throat model volume. Throat models representing high, median, and low oropharyngeal filtration in healthy adults have been identified.  相似文献   
105.
Zygophyllum fahago is a herbaceous plant found widely in the Mediterranean area. There are no previous reports of its allergenicity. An aerobiologic and clinical survey was conducted in Murcia, southern Spain, to determine the quantity of airborne pollen and establish the possible role of this pollen as a cause of allergic symptoms. With a Hirst volumetric trap, we determined the atmospheric concentrations of this pollen in 1993, 1994,1995, and 1996. Of 1180 patients tested, 181 (15,34%) had a positive skin test. To determine its allergenicity, we divided 47 patients into three groups: in group 1, all the patients had symptoms of rhinoconjunctivitis plus asthma; in groups 2 and 3, rhinoconjunctivitis. In group 1, we performed a bronchial provocation test (BPT): in groups 2 and 3, we performed nasal provocation (NPT) and conjunctival provocation (CPT) tests, respectively, SDS-PAGE was used to characterize the antigenic fractions and RAST inhibition to determine cross-reactivity with other pollens. The pollen dispersion period is from May to September (445 grains/m3), BPT was positive in 13 of 15 patients, NPT in 14 of 16 patients, and CPT in 13 of 16 patients. RAST inhibition revealed cross-reactivity with Mercurialis, Ricinus, Olea. and Betula. SDS-PAGE identified 25 IgE antibody-binding components, five of which (60, 65, 41, 38, and 15.5/14,7 kDa) were recognized by 40% of the sera. By SDS-PAGE immunoblotting with sunflower antiprofilin rabbit serum and affinity chromatography we established that the Z. fahago extract has profilin. This study shows that this pollen becomes airborne and elicits an IgE response which triggers respiratory symptoms in allergic subjects.  相似文献   
106.
Patients with morbid obesity present a series of functional and morphologic alterations and require a careful planning for anesthetic management. We report a case of a woman weighing 260 kg who was operated on twice for the treatment of her base condition. In the first operation, general anesthesia was carried out and in the second one, epidural anesthesia was conducted. Main complications included hypoxemia and hypercapnia which persisted during the first week after operation carried out under general anesthesia.  相似文献   
107.
We studied 362 fractures of the femur that had occurred during the years 1950-57 and 1973-83, and 849 fractures of the tibia that occurred during the the years 1950-55 and 1980-83. There was an increase in age-specific incidence over aged 60 years. The risk of low-energy femoral shaft fractures also had increased in elderly women. Both fracture types shifted their age- and sex-specific incidence in the direction of a fragility pattern. There was no increase in the incidence of tibial shaft fractures. Fracture type, site, and degree of displacement of the tibial fractures remained unchanged during the 30 years, i.e, they were predominantly distal, longitudinal fractures with moderate displacement.  相似文献   
108.
In order to clarify the physiological role in vivo of H2O2-detoxifying enzymes at low and high levels of O2 tension we studied catalase (CAT), glutathione peroxidases (GP), and in vivo peroxidation (TBA-RS) in the lung and heart of Rana perezi frogs chronically treated with hyperoxia, aminotriazole (AT) -a CAT inhibitor-, or both. Hyperoxia did not change CAT, GP or TBA-RS. Aminotriazole caused an almost complete depletion of CAT, a 30% decrease of GP and a 132% (lung) to 200% (heart) increase of TBA-RS. Changes similar to these were found in the group treated with AT in hyperoxia. No mortality or changes in total or organ weight occurred in the experimental groups. Main conclusions are: (1) The maximal hyperoxia tolerance showed by frogs among vertebrates does not need antioxidant enzyme induction from lung or heart and is probably related to the presence of high constitutive levels of GP in relation to metabolic rate. (2) Even in normoxia the tissues present significant amounts of H2O2, and CAT is needed to avoid oxidative damage. GP does not compensate its absence. The implications of these results in relation to oxygen toxicity in man is discussed.  相似文献   
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