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991.
Clinical trials with intravenous cladribine infusions in pretreated patients with Waldenstr?m's macroglobulinaemia have shown a response rate of 40%. Our pharmacokinetic studies revealed that the bioavailability of subcutaneous cladribine is complete but that the concentration-time profile is very different from intravenous administration. We designed this phase II multi-institutional trial to study the activity and toxicity of cladribine given as s.c. bolus injections in patients with symptomatic Waldenstr?m's macroglobulinaemia. Between May 1993 and October 1995, 25 patients were accrued: male/female 18/7, median age 65 years (range 44-85). All except one patient had been pretreated with more than one regimen (median 2, range 0-10). 18 patients had progressed under previous therapy and six were in relapse. All patients received cladribine for a total dose of 0.5 mg/kg per cycle as s.c. bolus injections divided over 5 d at > or = 4 week intervals, for a maximum of six cycles. All 25 patients were evaluable for toxicity and response. A total of 67 cycles were administered (median 3 cycles, range 1-6). Overall response rate including disease stabilization which had been progressive under previous therapy was 68%. 10 patients (40%, 95% CI 21-61%) achieved a partial remission. Seven responders had been progressive under previous therapy. Maximum responses were reached no later than the third cycle. Median time to treatment failure and remission duration were 4.4 (range 0.5-33) and 8 months (5-29), respectively. Four patients (16%) suffered from infections W.H.O. grade > or = 2 (pneumonia grade 2, Staphylococcus septicaemia grade 3, viral encephalitis and pneumonia, both grade 4 with complete resolution). No other severe adverse events were observed. Cladribine given as s.c. 5 d bolus injections was found to be active in pretreated Waldenstr?m's macroglobulinaemia and resulted in durable remissions.  相似文献   
992.
OBJECTIVES: This study assessed the potential impact of fetal ultrasound screening on the number of newborns affected by cardiac anomalies. METHODS: A decision model was developed that included the prevalence and history of congenital heart disease, characteristics of ultrasound, risk of abortion, and attitude toward pregnancy termination. Probabilities were obtained with a literature survey; sensitivity analysis showed their influence on expected outcomes. RESULTS: Presently, screening programs may prevent the birth of approximately 1300 severely affected newborns per million second-trimester pregnancies. However, over 2000 terminations of pregnancy would be required, 750 of which would have ended in intrauterine death or spontaneous abortion. Further, 9900 false-positive screening results would occur, requiring referral. Only the sensitivity of routine screening and attitude toward termination of pregnancy appeared to influence the yield substantially. CONCLUSIONS: The impact of routine screening for congenital heart disease appeared relatively small. Further data may be required to fully assess the utility of prenatal screening.  相似文献   
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Changes of the left ventricle after myocardial infarction are characterized by geometric, structural, and vascular alterations, which have been summarized under the term "remodeling". This process takes place in the infarct region as well as in the surviving myocardium. Depending on to the size of infarction and the degree of neurohumoral activation, the left ventricle demonstrates diastolic dysfunction which may finally lead to systolic failure. The residual myocardium develops progressive myocyte hypertrophy and interstitial fibrosis. These structural alterations are due to changes in loading conditions and stimulation of the neurohumoral system with an activation of local paracrine and autocrine factors. Myocardial function can be assessed by different non-invasive (echocardiography, radionuclide ventriculography, magnetic resonance imaging, etc.) or invasive methods (e.g., simultaneous pressure-volume measurements). "Myocardial tagging" based on magnetic resonance imaging allows the assessment of 3D-motion of the left ventricle by labelling specific myocardial regions with a rectangular grid. A systolic "wringing" motion with clock-wise rotation at the base and counter-clockwise rotation at the apex has been described in normal subjects. In the ischemic myocardium, delayed relaxation with a prolonged back-rotation (untwisting) has been reported during early diastole, whereas decreased systolic contraction with delayed diastolic rotation has been observed in non-Q-wave infarction. In patients with anterolateral aneurysms, a complete loss of systolic rotation has been demonstrated. The prognostic significance of LV "remodeling" has been emphasized by several authors: The size of infarction, LV volume, LV ejection fraction, as well as the degree of neurohumoral activation have been identified as being associated with an unfavorable clinical outcome. Yearly mortality rates have been reported to range between 15 and 17% in patients with large infarcts and marked LV dilatation and between 3 and 7% in patients with small to medium-sized infarcts.  相似文献   
995.
The heat flux densities through thin layers of casting slag have been measured with a soft cooling heat flux probe which made smooth probe/slag interfaces. Thus the contact resistance was avoided. The evaluated effective thermal conductivities were applied, together with the data on the contact resistance, to compute the “system conductivities” existing in the continuous casting “system” water cooled copper/slag/strand. The refractive index and absorption spectrum were measured and used to deduce functions for the radiative and conductive (phonon) conductivities. Although precise values could not be obtained, due to the many assumptions involved, the data indicate that the conductive conductivity does not change drastically at high temperatures and on melting.  相似文献   
996.
The potent accessory properties of dendritic cells (DC) develop sequentially during a process termed "maturation." Splenic DC undergo functional maturation in vivo in response to the bacterial product LPS and migrate from the marginal zone to the T cell areas. The redistribution of fully mature DC, which present Ags encountered in the periphery, in the T cell area is likely to result in T cell priming. Unexpectedly, we found that DC rapidly die by apoptosis once they have entered the T cell zone. Injection of OVA peptide in OVA-specific, TCR-transgenic mice strongly delays the LPS-induced apoptosis of DC in situ. We conclude that mature DC are programmed to die unless they receive a survival signal from T cells and that the regulation of DC survival may be a mechanism aimed at controlling the initiation and the termination of the immune response.  相似文献   
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999.
OBJECTIVE: To determine whether postmenopausal oestrogen replacement therapy affects carotid artery pulsatility index. DESIGN: A prospective double-blind placebo controlled trial. SETTING: University associated teaching hospital. PARTICIPANTS: Twenty-eight postmenopausal women who were more than 12 months postmenopausal and who had not taken exogenous oestrogen. INTERVENTIONS: Independent randomisation to receive oral oestradiol (2 mg daily) or placebo for 20 to 24 weeks. MAIN OUTCOME MEASURES: Internal carotid artery Doppler pulsatility index, measured within one centimetre of the carotid bifurcation. RESULTS: Replicate data were available from 27 women. The mean pulsatility index decreased by -0.11 in 15 women receiving oestradiol, compared with a mean rise of 0.05 in the 12 women who received placebo (P = 0.006, 95% CI for treatment difference 0.06-0.31). CONCLUSIONS: Oestrogen replacement decreases postmenopausal carotid artery pulsatility index, probably reflecting decreased peripheral vascular resistance. This is a further mechanism whereby hormone replacement therapy may impart cardiovascular protection.  相似文献   
1000.
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