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31.
Mark R. Beauchamp Albert V. Carron Serena McCutcheon Oliver Harper 《Annals of behavioral medicine》2007,33(2):200-206
Background: A growing body of research suggests that older exercisers prefer to exercise alone rather than in group-based settings. One
limitation of these studies, however, has been that researchers have failed to take into account the age-related characteristics
of groups when asking adults about their preferences for exercise settings.Purpose: The overall purpose of this study was to examine the exercise preferences of 947 adults for involvement in standard exercise
classes populated by participants from various categories across the age spectrum.Results: The results revealed that when faced with the prospect of exercising with considerably older or younger exercisers, participants
found such an exercise context to be largely unappealing. However, in accordance with the basic tenets of self-categorization
theory, the results revealed that older and younger adults alike express a positive preference for exercising in standard
exercise classes comprised of similarly aged participants.Conclusions: The findings of this study challenge a growing call for exercise interventions for older adults to be primarily directed
at the individual-level, and suggest that group-related intervention strategies may indeed be attractive to older exercisers. 相似文献
32.
This retrospective analysis reviews the clinical experience of a major urban referral hospital with diffuse malignant pleural mesothelioma during the 14-year period from 1973 through 1986. Seventy-five cases of definite or equivocal mesothelioma were identified. There were four cases of primary malignant peritoneal mesothelioma, seven cases of benign fibrous mesothelioma, and 64 cases of diffuse malignant pleural mesothelioma. In 43 cases (67%) of diffuse malignant pleural mesothelioma, there was historic evidence of asbestos exposure. In 21 cases (33%), there was no known history of asbestos exposure. An increase in annual incidence of diffuse malignant pleural mesothelioma was observed over the study period, from three cases in 1973 to ten cases in 1986. Despite greater awareness of this disease, the diagnosis remains a difficult one to establish given the nonspecific symptoms, signs and radiographic appearance, variable histologic appearance, and poor diagnostic sensitivity and specificity of thoracentesis and closed pleural biopsy. Thoracotomy, thoracoscopy, and CT-guided needle biopsies gave higher yields and are the diagnostic measures of choice when diffuse malignant pleural mesothelioma is suspected. 相似文献
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Jeffrey T Cope MD Michael C Mauney MD David Banks BS Oliver A.R Binns MD Christopher L Moore BS Jeffrey J Rentz BS Kimberly S Shockey MS R.Christoper King MD Irving L Kron MD Curtis G Tribble MD 《The Annals of thoracic surgery》1997,63(6)
Background. Hypoxia and warm ischemia produce severe injury to cardiac grafts harvested from non–heart-beating donors. To potentially improve recovery of such grafts, we studied the effects of intravenous phenylephrine preconditioning.Methods. Thirty-seven blood-perfused rabbit hearts were studied. Three groups of non–heart-beating donors underwent intravenous treatment with phenylephrine at 12.5 (n = 8), 25 (n = 7), or 50 μg/kg (n = 7) before initiation of apnea. Non–heart-beating controls (n = 8) received saline vehicle. Hypoxic cardiac arrest occurred after 6 to 12 minutes of apnea, followed by 20 minutes of warm in vivo ischemia. A 45-minute period of ex vivo reperfusion ensued. Nonischemic controls (n = 7) were perfused without antecedent hypoxia or ischemia.Results. Phenylephrine 25 μg/kg significantly delayed the onset of hypoxic cardiac arrest compared with saline controls (9.6 ± 0.5 versus 7.7 ± 0.4 minutes; p = 0.00001), yet improved recovery of left ventricular developed pressure compared with saline controls (57.1 ± 5.3 versus 41.0 ± 3.4 mm Hg; p = 0.04). Phenylephrine 25 μg/kg also yielded a trend toward less myocardial edema than saline vehicle (p = 0.09).Conclusions. Functional recovery of nonbeating cardiac grafts is improved by preconditioning. We provide evidence that the myocardium can be preconditioned with phenylephrine against hypoxic cardiac arrest.(Ann Thorac Surg 1997;63:1664–8) 相似文献
35.
Cynthia S. Pomerleau Anne W. Garcia Ovide F. Pomerleau Oliver G. Cameron 《Psychoneuroendocrinology》1992,17(6):627-638
Nicotine intake, menstrual and smoking withdrawal symptomatology, and baseline cortisol and MHPG were assessed in nine women smokers under conditions of ad lib smoking and overnight abstinence in three menstrual phases (early follicular, mid-to-late follicular, and late luteal). A trend towards higher nicotine intake p <0.100 was observed in the mid-to-late follicular phase. Although me menstrual symptomatology was not significantly elevated during the smoking abstinence condition overall, abstinence appeared to prevent the normal reduction in symptomatology during the mid-to-late follicular phase that occurred under conditions of ad lib smoking. Menstrual and withdrawal symptoms were highly correlated, and both were most pronounced during the late luteal/abstinence condition. The smoking-specific item “craving” reflected this pattern, though in attenuated form, suggesting that the observed exacerbation of withdrawal symptomatology was not simply due to generalized dysphoria, as queried in both instruments. MHPG was significantly elevated in the late luteal phase, whereas cortisol was significantly higher during ad lib smoking than during abstinence and tended to be highest in the mid-to-late follicular phase. Further investigation will be needed to determine the functional significance of these findings for understanding and treating smoking in women. 相似文献
36.
Claude Linassier Pascale Poumier-Gaschard Jean-Louis Bremond Carole Barin Oliver Haillot Jean Pierre Lamagnere Philippe Colombat 《Cancer chemotherapy and pharmacology》1992,30(3):233-234
Summary Simultaneous tumors are rarely encountered during the course of acute leukemias. We report on a case of seminoma of the testis that occurred during the evolution of acute myelogenous leukemia. To our knowledge, this stimultaneous association has not previously been described, but a causal relationship was not apparent in the present case. The likelihood of a common carcinogenesis existed, but direct exposure to carcinogens could not be established. Although the results of a physical examination and echography were normal at the time of diagnosis, we cannot exclude the presence of microscopic cancer of the testis. Since the dissemination pattern of seminoma is usually slower than that observed in this case and the disease remains limited to the lymph nodes for long periods following dissemination, the rapid development of the present case might have been attributable to the immunosuppression and the scrotal sepsis that occurred during the induction therapy. Immunosuppression might have stimulated the progression of a primary microscopic seminoma and the development of metastasis, whereas the scrotal sepsis and inflammation might have favored the occurrence of metastasis through bypass of the lymphatic barrier. 相似文献
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38.
The cattle major histocompatibility complex (MHC) class II DR gene product is a heterodimer encoded by the BoLA-DRA and -DRB3 genes. Several groups have isolated cDNA and genomic clones for these genes, but their full genomic organization has not been described. We used a combination of long-range polymerase chain reaction (PCR), cloning and sequencing to define the organization of the DRB3 gene on existing genomic clones and in genomic DNA. We estimate the size of the coding region to be 11.4 kbp. Sequencing of full-length PCR clones from two different haplotypes confirmed that they carried complete DRB3 genes and allowed the design of probes and primers to isolate and characterize the DRB3 promoter and 3' end. Fragments carrying the 5' end of the DRB3 gene and its promoter were identified on bacterial artificial chromosome (BAC) clones carrying the BoLA-DR genes. A 10-kbp promoter fragment was subcloned from one clone and a 1.7-kbp region including exon 1 and the promoter was sequenced. A 3-kbp fragment encoding exons 4-6 and the entire 3' untranslated region of the DRB3 gene was isolated from lambda clone A1 and sequenced. This provides us with improved characterization of the DRB3*0101 and DRB3*2002 alleles, and also subcloned 5' and 3' flanking regions of the polymorphic DRB3 gene for use in functional studies. 相似文献
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