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141.
A tracer kinetic procedure was developed for the measurement of monoamine oxidase type B (MAO-B) activity using L-[11C]deprenyl and positron emission tomography (PET). The kinetic model consisted of two tissue compartments with irreversible binding to the second compartment (three rate constants). In addition, a blood volume component was included. Special attention was given to the accurate measurement of the plasma and whole blood input functions. The method was applied to the measurement of the dose-response curve of a reversible MAO-B inhibitor (Ro 19-6327). From the results, it followed that the rate constant for irreversible binding (k3) appeared to be a better index of MAO-B activity than the net influx constant Ki. Furthermore, regional analysis demonstrated that Ki, but not k3, was flow dependent. This implies that full kinetic analysis is required for an accurate assessment of MAO-B activity.  相似文献   
142.
The expression of two heat shock proteins, HSP72 and p57, in addition to ubiquitin, has been studied immunocytochemically in nine amyotrophic lateral sclerosis (ALS) cases and 10 age-matched controls. HSP72 and p57 antibodies did not identify the characteristic ubiquitin-immunoreactive inclusions present in anterior horn cells in ALS spinal cord. Antibodies to HSP72, but not to p57 or ubiquitin, strongly labelled structures corresponding to polyglucosan bodies in spinal grey matter. Such immunoreactive profiles were more abundant in ALS cases, although they were also present in control material. They were sometimes identified by haematoxylin and eosin and periodic acid Schiff reaction, but were not labeled by phosphotungstic acid haematoxylin or by antibodies to glial fibrillary acidic protein. Although ubiquitin, HSP72 and p57 are stress-induced proteins, they are expressed differently and might therefore have different significance in neuronal degeneration.  相似文献   
143.
Bronchoalveolar lavage fluid neutrophils were studied by the cytologic methods in 58 patients with chronic bronchitis, 63 ones with bronchiectasis, and 8 normal controls. The study included cytospectrophotometry of myeloperoxidase and alkaline phosphatase activity and estimation of active oxygen-producing cells in the NBT test. Neutrophilic functional activity was different in the patients with chronic bronchitis and bronchiectasis. Neutrophilic myeloperoxidase and alkaline phosphatase activities were lower in the patients with chronic bronchitis than in those with bronchiectasis, whereas the counts of cells active in the NBT test were low in both patient populations.  相似文献   
144.
CGS 10078B (CGS; 1-[2,3-dihydro-1,4-(2S)-benzodioxin-2-yl]-5-[2,3-dihydro-1,4-(2R)- benzodioxin-2-yl]-3-(1R,5S)-aza-1,5-pentanediol methane sulfonate) is an agent with alpha- and beta-receptor and calcium channel blocking actions. To study its antiarrhythmic activity, cats were anesthetized with alpha-chloralose, ventilated, and given atropine and gallamine. CGS (10 or 20 mg/kg, i.v.) was infused 15 min prior to ouabain. Bolus injections of ouabain (25 micrograms/kg, i.v.) were given every 15 min until death (D). Some cats were pretreated with reserpine (R; 5 mg/kg, i.p.) 24 h prior to the experiment. In other cats 6-hydroxydopamine (6-OHDA; 20 mg/kg, i.v.) was administered 3 days prior to CGS 20 mg/kg and ouabain. Data were compared with those of Lathers [Eur. J. Pharmacol. 64: 95, 1980], i.e., with 12 cats who received only ouabain and with 11 pretreated with timolol (T; 5 mg/kg, i.v.) prior to ouabain. After CGS (10 or 20 mg/kg, i.v.), but just prior to the first dose of ouabain, the blood pressure (BP) was decreased (p less than 0.05) from control (165 +/- 6 vs. 96 +/- 7, and 136 +/- 5 vs. 90 +/- 10 mm Hg, respectively). Comparable heart rate (HR) values were also decreased (p less than 0.05) from 225 +/- 17 to 166 +/- 14 and from 193 +/- 8 to 152 +/- 6 beats/min. 11 min after T, BP and HR had decreased (p less than 0.05) from 133 +/- 6 to 103 +/- 7 mm Hg and from 134 +/- 4 to 104 +/- 6 beats/min, respectively. Ouabain did not influence these decreases in BP and HR. CGS (10 or 20 mg/kg, i.v.) increased (p less than 0.05) the time to ouabain-induced arrhythmia (AR) and D. The magnitude of the protection appeared to be similar to that afforded by T. R given prior to CGS (20 mg/kg, i.v.) also increased the time to ouabain-induced AR and D while 6-OHDA increased the time to AR. The CGS protection against ouabain-induced AR was still present in animals pretreated with R or 6-OHDA. This indicates that the antiarrhythmic affect is not dependent upon adrenergic neuronal blockade.  相似文献   
145.
Reported in this paper are postoperative results recorded from 120 patients, 3 years after selective proximal vagotomy for uncomplicated duodenal ulcer. There was no intraoperative lethality and no recurrence in 96.7 per cent of all cases, while Visick grades I on II were recorded from 98.2 per cent. Radiologically and gastroscopically detected pathological processes receded soon. Average postoperative reduction in acid secretion was 66.2 per cent in BAO and 46.8 per cent in MAO. Acid values re-increased thereafter, and three years later reduction rates still amounted to 43.7 per cent in BAO and 28.6 per cent in MAO. Indications for proximal gastric vagotomy are discussed in some detail.  相似文献   
146.
Sebum excretion rate was measured by a photometric technique. We demonstrated a high correlation between sebum excretion rates on the left and right sides of the upper back and between back and forehead skin. Sebum excretion rate measurements overlying an open comedone (blackhead) were significantly lower than those obtained from normal skin. This observation demonstrates a functional obstruction to the outflow of sebum and would suggest that the lack of involvement of open comedones in inflammatory acne is not because of the maintenance of a free flow of sebum.  相似文献   
147.
A 65-year-old man with spontaneous rupture of the esophagus survived with a direct suture of the esophagus 15 hours after the onset of symptoms. Endoscopic examination of the esophagus was especially of great help in determining the surgical procedure in this patient, and we want to stress the importance of prompt diagnosis and immediate surgery for this disease.  相似文献   
148.
Effects of dexamethasone on central and peripheral ACTH systems in the rat   总被引:1,自引:0,他引:1  
To investigate the simultaneous effects of dexamethasone on peripheral and central adrenocorticotropic hormone (ACTH) systems, rats were treated with dexamethasone or saline for 4 days. Pituitary, plasma, hypothalamus and cerebrospinal fluid (CSF) were then collected and analyzed for ACTH immunoreactivity. Additionally, hypothalamic tissue extracts were analyzed for corticotropin-releasing hormone (CRH) immunoreactivity. Dexamethasone significantly lowered peripheral levels of ACTH as measured in pituitary and plasma. Hypothalamic ACTH content significantly increased while CSF ACTH significantly decreased with dexamethasone treatment. Hypothalamic CRH concentrations showed a small but statistically insignificant decrease. These results suggest that prolonged exposure to dexamethasone affects central as well as peripheral ACTH activity, corroborate our previous findings in rhesus monkeys of decreased CSF ACTH in response to prolonged dexamethasone treatment, suggest that dexamethasone may inhibit the release of ACTH from hypothalamic neurons into the CSF, and provide evidence that the effect of dexamethasone on pituitary ACTH content is of greater magnitude than its effect on hypothalamic CRH.  相似文献   
149.
Roentgen endovascular occlusion with spiral emboli was used in 240 patients with different diseases. The introduction of spiral emboli into the arteries of abdominal and retroperitoneal organs was fulfilled through usual angiographic catheters. Duration of the arterial occlusion was checked up in the following angiographic examinations and showed the devices described to be appropriate for a continuous arterial blockade. No complications resulting from the introduction of the spiral embolus were noted.  相似文献   
150.
Snoring means obstructive breathing during sleep, and its most exaggerated form is obstructive sleep apnea. Mild snoring may respond to simple self-help remedies. Heavy snoring responds well to the surgical removal or reconstruction of obstructive elements in the hypopharynx, nasopharynx or nasal passages.  相似文献   
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