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排序方式: 共有10000条查询结果,搜索用时 15 毫秒
991.
Lesions typical of subacute cutaneous lupus erythematosus developed in an elderly woman after 6 months of PUVA (8-methoxypsoralen and longwave ultraviolet light) therapy for psoriasis. Pancytopenia, antibodies to double-stranded DNA, and hypocomplementemia developed concurrently with the appearance of the cutaneous lesions. With discontinuation of photochemotherapy, the cutaneous lesions disappeared and the pancytopenia improved. 相似文献
992.
993.
Critically ill cardiac patients often undergo mechanical ventilation. The interplay between pulmonary and cardiac mechanics is complicated and in many cases may result in impaired transfer of O2 from the atmosphere to the tissues. This article addresses the principles of pulmonary and peripheral gas exchange, as well as the mechanical effects of respiration on the circulation. 相似文献
994.
Prospective randomized comparison of mezlocillin therapy alone with combined ampicillin and gentamicin therapy for patients with cholangitis 总被引:3,自引:0,他引:3
W B Gerecht N K Henry W W Hoffman S M Muller N F LaRusso J E Rosenblatt W R Wilson 《Archives of internal medicine》1989,149(6):1279-1284
Forty-six patients with cholangitis were randomized to receive therapy with mezlocillin sodium (24 patients) or a combination of ampicillin sodium--gentamicin sulfate (22 patients). The biliary concentration of mezlocillin was 112 times higher than that of ampicillin and 778 times higher than that of gentamicin. The ratio of the concentration in serum or bile over the minimum inhibitory concentration against aerobic gram-negative bacilli (therapeutic index) was higher for mezlocillin than for either ampicillin or gentamicin. Twenty (83%) of 24 patients were cured following mezlocillin therapy compared with 9 (41%) of 22 patients after ampicillin-gentamicin therapy. The 3 patients with superinfection were in the ampicillin-gentamicin arm of the study. Fewer toxic or adverse effects occurred in association with mezlocillin treatment than with ampicillin-gentamicin treatment. Mezlocillin therapy was more effective, less toxic, and less expensive than treatment with ampicillin and gentamicin for patients with cholangitis. 相似文献
995.
Barium can induce spontaneous activity in cardiac non-pacemaker cells. The mechanism of barium induced diastolic depolarisation was studied in isolated ventricular myocytes, using a microelectrode technique. Barium (0.05-0.2 mmol.litre-1) decreased resting potential and caused the membrane potential at the end of the action potential to undershoot the diminished resting value temporarily, thereby inducing diastolic depolarisation. Resting membrane resistance was increased by Ba but at the end of phase 3 repolarisation the resistance temporarily decreased below its steady state diastolic value. In presence of Ba, hyperpolarisation abolished or reversed diastolic depolarisation. At the end of phase 3 repolarisation, membrane resistance was decreased, whether diastolic depolarisation was present, absent or reversed. A high [K]o (15.4 mmol.litre-1) decreased Ba effects on action potential, membrane resistance and diastolic depolarisation. Caesium decreased the Ba induced diastolic depolarisation and the associated increase in membrane resistance, but had little effect on spontaneous activity at depolarised levels. Barium induced an oscillatory potential, with increased membrane resistance. Noradrenaline plus low [Ba]o, and high [Ba]o alone (1-5 mmol.litre-1), can induce spontaneous activity. Thus, in myocardial cells barium induces diastolic depolarisation at polarised levels by a voltage and time dependent block of potassium conductance, which is modulated by action potential voltage changes. However, as [Ba]o is increased, spontaneous activity at a depolarised level may be related to the decay of potassium currents and to oscillatory potentials. 相似文献
996.
Breast preserving surgery or conservative surgery consists at present of a combination of a reduced operation--tumorectomy or wedge resection or subcutaneous mastectomy--with adequate radiotherapy whereby a doses of 40-50 Gy is used with or without an additional booster dose of 10 Gy. Recent studies of 5-year- and 10-year-survival rates after conservative management have been shown to be identical with radical operations (Rotter-Halsted, Patey-Auchincloss). In the Departments of Gynecology and Obstetrics of the Universities of Münster and Rostock the partial bilateral subcutaneous mastectomy with lymphadenectomy and irradiation is the preferred method of conservative management for breast cancer. Indications and technique are discussed. 相似文献
997.
998.
Effect of impact exercise on bone mineral density in elderly women with low BMD: a population-based randomized controlled 30-month intervention 总被引:4,自引:3,他引:1
Raija Korpelainen Sirkka Keinänen-Kiukaanniemi Jorma Heikkinen Kalervo Väänänen Juha Korpelainen 《Osteoporosis international》2006,17(1):109-118
Evidence of the effect of exercise on bone loss comes mainly from studies in voluntary postmenopausal women, and no population-based, long-term interventions have been performed. The purpose of this population-based, randomized, controlled trial was to determine the effect of long-term impact exercise on bone mass at various skeletal sites in elderly women with low bone mineral density (BMD) at the radius and hip. Participants ( n =160) were randomly assigned to 30 months either of supervised and home-based impact exercise training or of no intervention. The primary outcome measures were femoral neck, trochanter and total hip BMD, and the secondary outcomes were bone density measures at the radius and calcaneum. Outcomes were assessed at baseline, 12 months and 30 months using blinded operators. The analyses were performed on an intention-to-treat analysis. Mean femoral neck and trochanter BMD decreased in the control group [–1.1%, 95% confidence interval (CI) –0.1% to –2.1% and –1.6%, 95% CI –0.4% to –2.7%], while no change occurred in the exercise group. Mean trochanter BMC decreased more in the control group (–7.7%, 95% CI –9.7% to –5.6% vs. –2.9%, 95% CI –5.3 to –0.9). There were six falls that resulted in fractures in the exercise group and 16 in the control group during the 30-month intervention ( P =0.019). A significant bone loss occurred in both groups at the radius and calcaneum. In multivariate analysis, weight gain was associated with increased BMD and BMC at all femur sites both in the exercise group and in the pooled groups. In conclusion, impact exercise had no effect on BMD, while there was a positive effect on BMC at the trochanter. Exercise may prevent fall-related fractures in elderly women with low bone mass.There was no conflict of interest. 相似文献
999.
Ana L Hermogenes Michael Richardson Arinos Magalhaes Armando Yarleque Edith Rodriguez Eladio F Sanchez 《Toxicon》2006,47(4):490-494
Lachesis venom plasminogen activator (LV-PA) is a 33-kDa serine proteinase isolated from bushmaster (Lachesis muta muta) snake venom, which activates the fibrinolytic system in vitro. This study has examined the effect of the plasma proteinase inhibitor alpha2-macroglobulin (alpha2-M) towards LV-PA and compares it with the effect on tissue type plasminogen activator (t-PA). The proteolytic activity of LV-PA alone or previously incubated with human plasminogen (Plg) on the large molecular mass protein substrates, dimethylcasein (DMC) and fibrinogen (Fg) was completely inhibited by human alpha2-M. However, the synthetic peptides Tos-Gly-Pro-Lys-pNA and H-D-Pro-Phe-Arg-pNA (S-2302) were hydrolyzed with almost no reduction in rate. At pH 7.4 and 37 degrees C the proteinase (0.15 microM over 15 min) interacted with alpha2-M, and each mole of alpha2-M bound 2 mol of enzyme. Sodium dodecyl sulfate gel electrophoresis of reduced samples showed that the interaction of alpha2-M with either LV-PA or t-PA preincubated with Plg resulted in the formation of approximately 90 kDa fragments and high molecular mass complexes (Mr 180 kDa), generated by the incubation mixture (LV-PA or t-PA) and Plg. The data suggest that LV-PA is a direct-type PA and its fibrinolytic effect can be reduced by alpha2-M in vivo. 相似文献
1000.