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41.
Insulinlike growth factor 1 production is inhibited in human sepsis   总被引:7,自引:0,他引:7  
We studied the response of 14 normal volunteers and five septic patients to a 48-hour course of exogenous biosynthetic human growth hormone (hGH) or placebo. Six normal controls (group 1) received saline, eight normal controls received hGH (group 2), and five septic patients also received biosynthetic hGH (group 3). Urinary urea excretion declined, and splanchnic amino acid uptake was maintained only in group 2 subjects. Septic patients exhibited changes in amino acid and urea dynamics comparable to those of subjects receiving placebo. Insulinlike growth factor 1 (IGF-1) production and plasma concentrations increased in group 2 in a fashion corresponding to the changes in nitrogen exchange, whereas septic patients exhibited no change in IGF-1 level. Therefore, in this septic patient group, exogenous hGH was ineffective in attenuating nitrogen losses and stimulating IGF-1 production. This supports the hypothesis that IGF-1 is a mediator of the anabolic effect of hGH.  相似文献   
42.
In 1984, a prospective cohort study, Coronary Artery Risk Development in Young Adults (CARDIA) was initiated to investigate life-style and other factors that influence, favorably and unfavorably, the evolution of coronary heart disease risk factors during young adulthood. After a year of planning and protocol development, 5,116 black and white women and men, age 18-30 years, were recruited and examined in four urban areas: Birmingham, Alabama; Chicago, Illinois; Minneapolis, Minnesota, and Oakland, California. The initial examination included carefully standardized measurements of major risk factors as well as assessments of psychosocial, dietary, and exercise-related characteristics that might influence them, or that might be independent risk factors. This report presents the recruitment and examination methods as well as the mean levels of blood pressure, total plasma cholesterol, height, weight and body mass index, and the prevalence of cigarette smoking by age, sex, race and educational level. Compared to recent national samples, smoking is less prevalent in CARDIA participants, and weight tends to be greater. Cholesterol levels are representative and somewhat lower blood pressures in CARDIA are probably, at least in part, due to differences in measurement methods. Especially noteworthy among several differences in risk factor levels by demographic subgroup, were a higher body mass index among black than white women and much higher prevalence of cigarette smoking among persons with no more than a high school education than among those with more education.  相似文献   
43.
A 74 year old man with light-chain myeloma developed amyloidosis with macroglossia after 10 years of therapy with alkylating agents. Over a 2-year period his tongue enlarged to persistently protrude from his mouth, inhibit his speech, interfere with normal swallowing and eventually threaten his airway. As a life-saving procedure the tumorous anterior two-thirds of the tongue was resected, with excellent primary healing. Within two weeks the patient's speech became comprehensible and his ability to eat returned to normal. Although rare in amyloidosis, massive macroglossia may occur and surgical correction is easily achieved.  相似文献   
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Thirty patients with AIDS without symptoms or signs of peripheral neuropathy were compared electrophysiologically with 23 age and sex matched healthy controls. The patients had a mean reduction in the amplitude of common peroneal compound muscle action potentials of 37% (95% CI 11-70%) and of sural sensory action potentials of 34% (CI 18-49%). Mean conduction velocity of both motor and sensory nerves was reduced by between 1 and 7 m/s, with a prolongation of F waves corrected for height of 5% in the arms and 13% in the legs. The distal motor latencies were unchanged. These changes did not correlate with the duration of AIDS, degree of immunosuppression (CD4 count), Body Mass Index, albumin or vitamin B12 level. Four patients had subclinical mononeuropathies. Sural nerve taken at necropsy from five asymptomatic AIDS patients had evidence of axonal degeneration without inflammation or demyelination. There was a mean reduction in myelinated fibre density of 30.5% (CI 10-51%) compared with eight age matched sudden death controls (p = 0.01). This loss principally affected the larger fibres. The pathological and electrophysiological changes indicate axonal degeneration and are similar to those seen in other chronic disorders and in normal ageing. It is concluded that this axonal degeneration is not specific to HIV.  相似文献   
46.
Cerebrospinal fluid gamma interferon (IFN-γ) and interleukin-10 levels in 39 patients with tuberculous meningitis were serially measured. Cytokine levels did not predict intracranial granuloma (IG) development, but IFN-γ levels in the top quartile after 1 month of therapy were highly associated (odds ratio = 18) with detection of an IG by computed tomography scanning.  相似文献   
47.
BACKGROUND: 3-Hydroxy-3-methylglutaryl CoA reductase inhibitors, commonly known as statins, account for the great majority of cholesterol-lowering drug use in the United States. Long-duration statin use was associated with substantially reduced risk of advanced prostate cancer in a recent large prospective study. METHODS: We examined the association between use of cholesterol-lowering drugs and prostate cancer incidence by disease stage and grade among 55,454 men in the Cancer Prevention Study II Nutrition Cohort. Proportional hazards modeling was used to calculate RRs. RESULTS: During follow-up from 1997 to 2003, we identified 3,413 cases of incident prostate cancer, including 317 cases of advanced prostate cancer. After adjustment for age, history of prostate-specific antigen testing, and other potential prostate cancer risk factors, current use of cholesterol-lowering drugs for 5 or more years was not associated with overall prostate cancer incidence (multivariate adjusted rate ratio, 1.06; 95% confidence interval, 0.93-1.20), but was associated with a marginally statistically significant reduction in risk of advanced prostate cancer (rate ratio, 0.60; 95% confidence interval, 0.36-1.00). CONCLUSION: These results provide some support for the hypothesis that long-term statin use is associated with reduced risk of advanced prostate cancer.  相似文献   
48.
Summary The clinical and biochemical effects of combined treatment with the two aromatase inhibitors aminoglutethimide and 4-hydroxyandrostenedione were evaluated in 10 patients suffering from advanced breast cancer. All patients had become resistant to treatment with one of the drugs before having combined treatment. Seven patients progressing on 4-hydroxyandrostenedione who had aminoglutethimide added to their treatment and achieved a further suppression of plasma oestradiol by a mean of 40.0% (p<0.05). Plasma oestrone was suppressed by a mean of 40.6% (p<0.025) and plasma oestrone sulphate was suppressed by a mean of 63.6% (p<0.025). Two of the patients, neither of whom had responded to 4-hydroxyandrostenedione alone, experienced objective tumour regression when aminoglutethimide was given in concert. Three patients progressing on aminoglutethimide who had 4-hydroxyandrostenedione added showed no further suppression of their plasma oestrogen levels, and no tumour regression was observed. These findings suggest a dose-response relationship between plasma oestrogen suppression at low postmenopausal levels and objective tumour response in breast cancer.  相似文献   
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There has been a traditional reluctance to remove a subluxed (ectopic) lens because of the high surgical risk. The use of closed intraocular microsurgical techniques, however, now allows greater intraoperative control with few complications. The authors present the results of subluxed lens extraction, by limbal or pars plana lensectomy, in 44 eyes of 24 patients, in which the indication for surgery was lens subluxation causing a reduction in visual acuity or uncorrectable refractive error. Visual acuity was improved in all cases after surgery, with no significant complications. Patients with reduced visual acuity secondary to ectopic lenses have a good visual prognosis after lensectomy using a closed intraocular microsurgical technique.  相似文献   
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