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We compared the effects of alpha 2- and beta-adrenoreceptor blockade on the central actions of catecholamines and metabolites of alpha-methyldihydroxyphenylalanine, epinephrine, alpha-methylnorepinephrine, and alpha-methylepinephrine were studied. I.c.v. and nucleus tractus solitarii (NTS) injections were carried out under anesthesia. Following i.c.v. injection, both epinephrine and methylepinephrine rapidly reduced blood pressure and heart rate, but the effects of methylnorepinephrine occurred somewhat later. Following microinjection into the nucleus of the solitary tract, epinephrine, methylepinephrine, and methylnorepinephrine all caused hypotension and bradycardia. The hypotensive effects of all 3 amines in the NTS were attenuated in additive fashion by yohimbine, an alpha 2 adrenoreceptor antagonist, and timolol, a beta-adrenoreceptor antagonist, whereas only yohimbine attenuated the bradycardia. The combination of yohimbine and timolol abolished the effects of the amines. These data suggest that in the NTS both alpha 2 and beta adrenoreceptor stimulation contribute to the hypotensive effects of these amines, but that only alpha 2 adrenoreceptors are principally involved in the heart rate response.  相似文献   
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Following administration of phenothiazines for schizophrenia, a 25-year-old patient developed a malignant neuroleptic syndrome followed by bilateral periarticular ossification of the knees, with severely limited motion. Two years later, the patient regained useful motion after bilateral excision of the ossified tissue and intensive physiotherapy. No recurrence of ossification was observed 3 years after operation, and the patient has maintained almost normal motion.  相似文献   
4.
BACKGROUND: In allergic conditions, the degree of skin test reactivity does not always correlate with the severity of clinical symptoms. Additional factors may contribute to the reported symptom severity. OBJECTIVES: To investigate the association between the magnitude of the skin prick test (SPT) response and the reported symptom severity in patients with allergic rhinitis and the possible modifying role of psychological factors. METHODS: One hundred four patients with allergic rhinitis and 23 with non-allergic rhinitis, classified according to their SPT response to 19 aeroallergens, were asked to rate the severity of five symptoms and to indicate whether their symptoms intensified on exposure to five common aeroallergens. They also completed a psychological questionnaire. Results Reported symptom severity of allergic rhinitis did not correlate with weal size for any of the aeroallergens tested or with the number of positive responses on SPT. It was not related to patient age, sex, or education. The reported symptoms severity correlated positively (0.29, P < 0.01) with reported symptom intensification on exposure to allergens. Moreover, both outcomes were positively associated with the psychological factors of hypochondriasis (0.20, P < 0.05 and 0.18, P < 0.05, respectively), and somatic awareness (0.24, P < 0.05 and 0.33, P < 0.01, respectively), but not with neuroticism. CONCLUSIONS: The severity of symptoms experienced by patients with allergic rhinitis is apparently not related to the magnitude of SPT response, but rather to psychological factors of hypochondriasis and somatic awareness. Physicians should be aware of the contribution of psychological factors to patient perceptions of the intensity of symptoms and of the intensification of symptoms on their exposure to allergens.  相似文献   
5.
Relatives of 22 schizotypal probands were evaluated for lifetime psychiatric diagnoses. Forty-four (N = 44) of the 97 available relatives were interviewed directly using the Diagnostic Interview Schedule. The rates of psychiatric diagnoses were compared with those of sixty-six (N = 66) of 140 relatives of 30 depressed patients. Family history of mental illness was ascertained by the informant method on the remainder of relatives of both proband groups. The rate of depression found in the relatives of schizotypal patients was 52% in those directly interviewed and 25.7% when informants' reports on unavailable relatives are pooled with direct interview data. These rates were not significantly higher than those found for the relatives of depressed probands (34.8% by direct interview and 21% including reports from informants). The high rates of depression in the relatives of schizotypal probands may indicate that schizotypal personality is associated with affective disorder and not only with schizophrenia. However, the high rates may be due to the presence of depressive character traits in relatives, which inflate the rates of dysthymic disorder and other chronic depressive disorders in the relatives of borderline patients.  相似文献   
6.
In order to make effective use of the statistical theory of design of clinical trials for chronic diseases such as periodontal disease, certain issues must be considered. Any clinical trial requires that the disease definition be well-specified; that patient eligibility be explicit; that the observation times be explicit; that the duration and endpoint of therapy be specified; that the duration of subsequent followup observation be specified; and that the unit of observation (e.g., tooth, set of teeth, patient) be defined. In a chronic disease, the potential biases that can readily be introduced by self-selection of patients who enter the trial and/or who return for subsequent observation become more important, because subjects are required to remain on treatment and/or observation for prolonged periods. Further, the cyclical nature of some chronic diseases may require special attention to baseline definitions of active disease and disease outcome. These issues are illustrated with examples from clinical trials of hypertension, breast cancer screening, and Polycythemia Vera. Implications for periodontal disease are discussed.  相似文献   
7.
Elevated serum levels of keratan sulfate (KS) and hyaluronate (HA) in patients with osteoarthritis (OA) have been reported. We measured KS and HA in dogs to determine if there was an elevation of these serum glycosaminoglycans in a canine model of OA. A single intraarticular injection of 1 mg of chymopapain into a shoulder joint increased serum KS by tenfold, and HA by less than twofold, in 24 hours. Serum KS and HA levels were 3-5-fold higher in dogs younger than 2 months of age than in older dogs. Serum KS and HA concentrations and synovial fluid KS concentrations were unrelated to spontaneous cartilage degeneration in 1-year-old dogs. Higher KS levels in synovial fluid correlated with higher KS levels in serum (r = 0.54, P less than 0.025). The mean KS concentration in sera of older dogs (greater than 3 years old) with OA was 37% higher than that in disease-free controls, but the difference between the groups was not statistically significant. Thus, elevated levels of serum KS and HA do not appear to have clinical significance in this model of OA.  相似文献   
8.
The diagnosis of hysteria is often incorrect and must be made with great caution. A retrospective study demonstrates that an erroneous diagnosis of hysteria is most likely to be given to females, the psychiatrically ill, patients who embellish and patients who present plausible psychogenic explanations for their illness. Movement disorders and paralysis are the neurologic disorders most frequently mislabeled as hysteria.  相似文献   
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Anorexia nervosa (AN) can cause both functional and structural cardiac complications, including a variety of different conduction abnormalities. This is the first case report of symptomatic diurnal second‐degree atrioventricular (AV) block (Mobitz Type I) in an adolescent with AN. We present a 12‐year‐old girl with AN, restrictor sub‐type who reported cardiac symptoms during weight gain, at the time of the initial diagnosis of AV block. Second‐degree AV block (Mobitz Type I) is discussed as a possible complication of the AN, as well as being an intrinsic conduction system disease. © 2009 by Wiley Periodicals, Inc. Int J Eat Disord 2009  相似文献   
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