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31.
BACKGROUND: An erythrocyte sedimentation rate (ESR) of at least 40 mm/h is considered an important requisite for the diagnosis of polymyalgia rheumatica (PMR). However, the relative frequency and clinical features of PMR in patients without a significantly increased ESR are unclear. METHODS: We performed a retrospective study of patients diagnosed as having PMR at the rheumatology divisions of 3 teaching hospitals. The diagnosis of PMR was established, regardless of the ESR, in 201 consecutive patients fulfilling the following criteria: (1) age 50 years or older, (2) severe proximal pain for more than 1 month in at least 2 of 3 areas: neck, shoulder, and/or pelvic girdles, and (3) rapid resolution of the syndrome while taking low-dose prednisone. Patients with giant cell arteritis were previously excluded from the study. The frequency and clinical features of patients with PMR and an ESR lower than 40 mm/h were analyzed. A comparative study between these patients and those with high ESRs was performed. RESULTS: An ESR lower than 40 mm/h was found in 41 patients (20.4%). These patients were younger (P = .02), were more frequently men (P = .006), and experienced a lower frequency of fever (P = .003) and weight loss (P = .07). Furthermore, these patients were characterized by an absence of anemia (P = .002) and a lower frequency of abnormal protein electrophoresis results (P < .001). Otherwise, their clinical syndrome, response to therapy, and frequency of relapses were similar to those of patients with classic PMR. In the entire population of 201 patients, the ESR was related to the length of treatment, number of areas involved, presence of fever, weight loss, and laboratory test result abnormalities, but it was unrelated to the duration of the illness prior to diagnosis. CONCLUSIONS: It is not uncommon to find a patient with PMR with an ESR lower than 40 mm/h. This syndrome is more frequent in men and it is clinically less severe than the classic form of PMR. Its recognition will allow these patients to benefit from an effective treatment with low-dose corticosteroids.  相似文献   
32.
In 3 experiments, participants memorized 8 examples, each exemplifying a different rule. Participants were asked to extend these rules to new examples. They practiced applications of the rules to examples over a period of 4 days (Experiment 1) or 5 days (Experiments 2 and 3). Although these rules were bidirectional, an asymmetry gradually built up such that participants became more facile in using the rules in the practiced direction. Participants also showed an advantage when the initial study example was repeated or when test examples were repeated. It is argued that skill acquisition involves development of a complex set of strategies based on use of rules and retrieval of examples. Four overlapping stages of skill acquisition are described.  相似文献   
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What ethical concerns regarding the application of new antidementia compounds are pertinent to the best interests of patients with Alzheimer's disease and their caregivers? Based on collected preliminary anecdotal accounts, these concerns are important and should be considered carefully by clinicians, researchers, and families.  相似文献   
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Diabetes mellitus positive for antibodies to glutamate decarboxylase is heterogeneous as far as the degree of impairment of endogenous insulin release, though antibodies to glutamate decarboxylase are the most useful marker for future insulin deficiency. To investigate what determines the prognosis of diabetes mellitus positive for antibodies to glutamate decarboxylase, we measured HLA-DRB1 alleles in three groups: 77 cases of insulin-dependent diabetes mellitus (IDDM), 44 of non-insulin-dependent diabetes mellitus (NIDDM) with secondary failure of oral hypoglycemic therapy, and 22 of NIDDM well controlled by diet and/or sulfonylurea agents. The proportion of susceptible and resistant alleles to IDDM determined the degree of insulin deficiency, and comparison of IDDM to NIDDM well controlled by diet and/or sulfonylurea agents revealed significant differences in DRB1*0405 (P < 0.05; RR = 2.82 and RR = 0.89, respectively) and DRB1*1502 (P < 0.001; RR = 0.02 and RR = 2.19, respectively). This study revealed that HLA-DRB1 alleles contribute to determining the prognosis of Japanese diabetes mellitus positive for antibodies to glutamate decarboxylase.  相似文献   
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Melatonin has been suggested as a physiological antagonist of calmodulin. In this work, we have characterized melatonin binding sites in Xenopus laevis oocyte membranes. Binding of [125I]melatonin by X. laevis oocyte membranes fulfills all criteria for binding to a receptor site. Binding was dependent on time, temperature, and membrane concentration and was stable, reversible, saturable, and specific. The binding site was also pharmacologically characterized. Stoichiometric studies showed a high-affinity binding site with a Kd of 1.18 nM. These data are in close agreement with data obtained from kinetic studies (Kd=0.12 nM). In competition studies, we observed a low-affinity binding site (Kd=63.41 microM). Moreover, the binding site was characterized as calmodulin. Thus, binding was dependent on calcium and blocked by anti-CaM antibodies in a concentration-dependent manner. Calmodulin inhibitor chlorpromazine also inhibited binding of the tracer. From these results, it is suggested that membrane-bound calmodulin acts as a melatonin binding site in Xenopus laevis oocytes, where it might couple cellular activities to rhythmic circulating levels of melatonin. This hypothesis correlates with the previous findings describing melatonin as a physiological antagonist of calmodulin.  相似文献   
39.
The human mineralocorticoid receptor of the steroid receptor family contains a modular structure with domain E which is considered to be a hormone binding domain. Recombinant protein approaches enabled us to clearly determine that this domain is also able to interact with F-actin (Kd about 2 microM) and G-actin. Moreover, it was revealed that this mineralocorticoid receptor domain/actin interaction was modulated by specific mineralocorticoid ligands. Agonist (aldosterone) steroid binding almost totally (91%) abolished the interaction with F-actin, while antagonist (progesterone) binding allowed more than 30% of this binding. Steroid modulation of the interaction between domain E and actin indicated that this actin binding is specific and could be essential for cellular mineralocorticoid receptor activity.  相似文献   
40.
This paper reviews the pathogenesis of Mycobacterium bovis infection in cattle, focusing on aspects relating to the host rather than the organism. A broad concept of pathogenesis has been considered and information is presented on sources and routes of infection, as well as the immune responses and pathology. In addition, data is presented on the excretion of M. bovis from tuberculous cattle.  相似文献   
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