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71.
M. A. Christmass B. Dawson C. Goodman P. G. Arthur 《Acta physiologica (Oxford, England)》2001,172(1):39-52
The role of work period duration as the principal factor influencing carbohydrate metabolism during intermittent exercise has been investigated. Fuel oxidation rates and muscle glycogen and free carnitine content were compared between two protocols of sustained intermittent intense exercise with identical treadmill speed and total work duration. In the first experiment subjects (n=6) completed 40 min of intermittent treadmill running involving a work : recovery cycle of 6 : 9 s or 24 : 36 s on separate days. With 24 : 36 s exercise a higher rate of carbohydrate oxidation approached significance (P=0.057), whilst fat oxidation rate was lower (P ≤ 0.01) and plasma lactate concentration higher (P ≤ 0.01). Muscle glycogen was lower post‐exercise with 24 : 36 s (P ≤ 0.05). Muscle free carnitine decreased (P ≤ 0.05), but there was no difference between protocols. In the second experiment a separate group of subjects (n=5) repeated the intermittent exercise protocols with the addition of a 10‐min bout of intense exercise, followed by 43 ± 5 min passive recovery, prior to sustained (40 min) intermittent exercise. For this experiment the difference in fuel use observed previously between 6 : 9 s and 24 : 36 s was abolished. Carbohydrate and fat oxidation, plasma lactate and muscle glycogen levels were similar in 6 : 9 s and 24 : 36 s. When compared with the first experiment, this result was because of reduced carbohydrate oxidation in 24 : 36 s (P ≤ 0.05). There was no difference, and no change, in muscle free carnitine between protocols. A 10‐min bout of intense exercise, followed by 43 ± 5 min of passive recovery, substantially modifies fuel use during subsequent intermittent intense exercise. 相似文献
72.
Treatment of tuberculosis in patients with advanced human immunodeficiency virus infection 总被引:18,自引:0,他引:18
P M Small G F Schecter P C Goodman M A Sande R E Chaisson P C Hopewell 《The New England journal of medicine》1991,324(5):289-294
BACKGROUND AND METHODS. Infection with the human immunodeficiency virus (HIV) increases the risk of tuberculosis and may interfere with the effectiveness of antituberculosis chemotherapy. To examine the outcomes in patients with both diagnoses, we conducted a retrospective study of all 132 patients listed in both the acquired immunodeficiency syndrome (AIDS) and tuberculosis case registries in San Francisco from 1981 through 1988. RESULTS. At the time of the diagnosis of tuberculosis, 78 patients (59 percent) did not yet have a diagnosis of AIDS, 18 patients (14 percent) were given a concomitant diagnosis of AIDS (as determined by the presence of an AIDS-defining disease other than tuberculosis), and the remaining 36 patients (27 percent) already had AIDS. The manifestations of tuberculosis were entirely pulmonary in 50 patients (38 percent), entirely extrapulmonary in 40 patients (30 percent), and both pulmonary and extrapulmonary in 42 patients (32 percent). The treatment regimens were as follows: isoniazid and rifampin supplemented by ethambutol for the first two months, 52 patients; isoniazid and rifampin supplemented by pyrazinamide and ethambutol for the first two months, 39 patients; isoniazid and rifampin, 13 patients; isoniazid and rifampin supplemented by pyrazinamide for the first two months, 4 patients; and other drug regimens, 17 patients. The intended duration of treatment for patients whose regimen included pyrazinamide was six months, and for patients who did not receive pyrazinamide, nine months. Seven patients received no treatment because tuberculosis was first diagnosed after death. Sputum samples became clear of acid-fast organisms after a median of 10 weeks of therapy. Abnormalities on all chest radiographs taken after three months of treatment were stable or improved except for those of patients who had new nontuberculous infections. The only treatment failure occurred in a man infected with multiple drug-resistant organisms who did not comply with therapy. Adverse drug reactions occurred in 23 patients (18 percent). For all 125 treated patients, median survival was 16 months from the diagnosis of tuberculosis. Tuberculosis was a major contributor to death in 5 of the 7 untreated patients and 8 of the 125 treated patients. Three of 58 patients who completed therapy had a relapse (5 percent); compliance was poor in all 3. CONCLUSIONS. Tuberculosis causes substantial mortality in patients with advanced HIV infection. In patients who comply with the regimen, conventional therapy results in rapid sterilization of sputum, radiographic improvement, and low rates of relapse. 相似文献
73.
Bowen D Thornquist M Goodman G Omenn GS Anderson K Barnett M Valanis B 《Journal of health psychology》2000,5(1):109-115
Behavioral research has an important role in increasing and maintaining participation in disease prevention trials, both in interventions and in follow-up visits. We conducted a randomized experiment among participants in the lung cancer chemoprevention trial, CARET (Carotene and Retinol Efficacy Trial) to test the effects of providing two incentives on retention. The items used for this study were a Certificate of Appreciation and one of two lapel pins, provided in a 2 2 design. Providing incentives, whether alone or in combination, had no statistically significant effect on retention by the two-year follow-up point. The successful implementation of this randomized incentive study has two implications for future research: (1) study of behavioral interventions and issues is feasible in the context of large controlled trials of disease end-points; and (2) such study is necessary to determine whether selected incentives can increase retention. 相似文献
74.
75.
polyhomeotic: a gene required for the embryonic development of axon pathways in the central nervous system of Drosophila 总被引:7,自引:0,他引:7
Hypomorphic alleles of the locus polyhomeotic (ph) produce multiple, homeotic-like transformations in adult flies that mimic dominant mutations in the Antennapedia and Bithorax complexes. Analysis of null alleles of ph has revealed a complex, embryonically lethal phenotype that includes cell death of the ventral epidermis and abnormalities in the patterns of expression of homeotic and segmentation genes. There is also a dramatic alteration in the pattern of axon pathways in the central nervous system, such that the wild-type array of segmentally repeated commissures and connectives is replaced by bundles of axons confined to the hemiganglia of origin. It is possible that this axonal phenotype is the result of loss of neuronal identity caused by abnormal homeotic and segmentation gene expression. 相似文献
76.
C. Goodman G. G. Rogers H. Vermaak M. R. Goodman 《European journal of applied physiology》1985,54(4):436-441
Summary We set out to demonstrate whether changes in plasma volume, haematocrit and some important blood constituents occurred after
swimming 100 m and 800 m, as well as monitoring the duration of these changes.
We measured exercise-induced changes in concentration of plasma constituents in eight subjects, and determined the expected
effects of haemoconcentration on these constituents. We also investigated the different biochemical responses occurring after
maximal exercise (100 m), as compared to submaximal exercise (800 m).
The haematocrit increased significantly after the 100 m swim and to a lesser extent after the 800-m swim, returning to basal
levels within 30 min. The plasma volume decreased by 16% on completion of the 100 m and by 8% on completion of the 800 m.
The blood lactate concentration increased 15-fold and 10-fold after the 100-m and 800-m swims respectively. The plasma potassium
concentration increased significantly immediately on completion of the 100-m swim, then decreased significantly at 2 1/2 and
5 min post-exercise, returning to near-basal values at 30 min. The potassium concentration measured after the 800-m event
did not differ significantly from basal levels, however the measured concentrations were significantly lower than the concentrations
expected on the basis of haemoconcentration. The plasma sodium concentrations measured after both 100-m and 800-m swims were
significantly increased. However, calculations correcting for haemoconcentration showed significant losses in toal circulating
sodium.
Our study demonstrates marked changes in plasma volume and certain blood constituents after maximal intensity swimming, and
less marked changes after submaximal exercise. We also demonstrated the importance of taking the effects of haemoconcentration
into account when evaluating changes in concentration of plasma constituents. 相似文献
77.
78.
79.
Iris (Lisch) nodules in neurofibromatosis 总被引:3,自引:0,他引:3
A group of 30 patients ranging from 4 to 56 years of age with the peripheral form of neurofibromatosis were evaluated for the presence of iris (Lisch) nodules. These nodules were observed in 73% of our cases and their presence was directly related to the severity of the skin manifestations of the disease. It is concluded that Lisch nodules are pathognomonic for neurofibromatosis and thus, their presence should be looked for in all suspected cases. 相似文献
80.
The mutational spectrum of brachydactyly type C 总被引:3,自引:0,他引:3
Everman DB Bartels CF Yang Y Yanamandra N Goodman FR Mendoza-Londono JR Savarirayan R White SM Graham JM Gale RP Svarch E Newman WG Kleckers AR Francomano CA Govindaiah V Singh L Morrison S Thomas JT Warman ML 《American journal of medical genetics》2002,112(3):291-296
Growth/differentiation factor-5 (GDF5), also known as cartilage-derived morphogenetic protein-1 (CDMP-1), is a secreted signaling molecule that participates in skeletal morphogenesis. Heterozygous mutations in GDF5, which maps to human chromosome 20, occur in individuals with autosomal dominant brachydactyly type C (BDC). Here we show that BDC is locus homogeneous by reporting a GDF5 frameshift mutation segregating with the phenotype in a family whose trait was initially thought to map to human chromosome 12. We also describe heterozygous mutations in nine additional probands/families with BDC and show nonpenetrance in a mutation carrier. Finally, we show that mutant GDF5 polypeptides containing missense mutations in their active domains do not efficiently form disulfide-linked dimers when expressed in vitro. These data support the hypothesis that BDC results from functional haploinsufficiency for GDF5. 相似文献