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31.
A workshop on "Antipsychotics: Past and Future" was convened by the National Institute of Mental Health (NIMH), Division of Services and Intervention Research (DSIR), on July 14, 1998, to review the results of recent antipsychotic drug research, discuss current standards of treatment, and identify areas needing further study. There has been a proliferation of new antipsychotic medications and a rapid increase in their clinical utilization. The new atypicals are beginning to supplant the older typical neuroleptic antipsychotics, and the scientific and ethical issues raised by this transition prompted the workshop. Given the apparent, albeit not fully defined, advantages of atypical drugs, particularly their safety profiles, the question is whether more comparisons with typical antipsychotics are warranted and whether clinical trial designs warrant (or would be justified in) the inclusion of typical drugs as standard active comparators. Workshop participants--including clinical researchers, patient advocates, bioethicists, and NIMH staff--discussed the conclusions drawn from current data, ethical issues for subjects in clinical trials, funding for ongoing studies using typical agents, and appropriate comparators for trials using atypical agents.  相似文献   
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Background

Although radiofrequency ablation (RFA) of nonresectable hepatic metastases has gained wide acceptance by showing survival benefit in selected patients, scattered reports are available regarding risk factors of local control of percutaneous RFA. The purpose of this study was to prospectively evaluate the factors influencing local tumor progression after percutaneous RFA of hepatic metastases.

Methods

Sixty-nine hepatic metastatic lesions in 54 patients were treated by percutaneous RFA. Efficacy was evaluated by contrast-enhanced computed tomography or magnetic resonance imaging at 1 month after ablation, then at 3-month intervals for the first year and biannually thereafter.

Results

The results of the log-rank test showed that tumor size of <3 cm (p = 0.024) and the absence of tumor contiguous with large vessels (p = 0.002) significantly correlated with local control for hepatic metastases. Cox regression analysis showed that the tumor size <3 cm and the absence of tumor contiguous with large vessels were independent factors (p = 0.055 and 0.009, respectively). The results of the log-rank test showed that neither the threshold post-ablation margin of 1.8 cm (p = 0.064) nor the presence of a tumor with subcapsular location (p = 0.134) correlated with the success of local control.

Conclusions

Percutaneous RFA is more effective in achieving local control in patients with hepatic metastases when the tumor size is <3 cm and not contiguous with large vessels.  相似文献   
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BackgroundWe previously reported that pressure overload of the left ventricle reduced myocardial infarct (MI) size in rabbits. The threshold of pressure overload was investigated in this study.MethodsPressure overload of the left ventricle was induced by partial snare of the ascending aorta in anesthetized, open-chest rabbits. Systolic left ventricular pressure (SLVP) was elevated 50% or 30% above baseline value by varying the degree of partial snaring. Different duration of pressure overload, including 10 minutes, 5 minutes, 3 minutes, or 2 minutes, was applied to determine the threshold of protective effects. Ischemic preconditioning was elicited by two 10-minute coronary artery occlusions and reperfusions. Ten minutes after different pretreatment, 1 hour occlusion of the left anterior descending coronary artery followed by 3 hours reperfusion was done to induce MI. The size of area at risk and MI were determined by blue dye injection and triphenyl tetrazolium chloride staining after experiments.ResultsPressure overload increase of SLVP 50% above baseline value for 10 minutes, 5 minutes, and 3 minutes significantly reduced MI size (18.5 ± 3.6%, 21.4 ± 1.9% and 21.6 ± 1.7%, respectively, vs. 26.6 ± 1.0% in the control group, mean ± standard deviation, p < 0.01). A 30% increase of SLVP by pressure overload for 10 minutes, 5 minutes and 3 minutes also significantly decreased MI size (20.5 ± 2.5%, 21.6 ± 2.3%, and 21.5 ± 2.3%, p < 0.01). Ischemic preconditioning significantly decreased MI size (19.9 ± 2.8%, p < 0.001). Pressure overload to elevate SLVP 50% or 30% above baseline value for 2 minutes did not significantly alter MI size (25.0 ± 2.3% and 26.0 ± 1.7%, p = 0.122 and p = 0.457). Two episodes of 2 minutes pressure overload did not significantly decrease MI size (25.0 ± 2.2% and 25.5 ± 2.2%, p = 0.118 and p = 0.281). The hemodynamics, area at risk, and mortality were not significantly different among all groups of animals.ConclusionPressure overload to raise SLVP either 50% or 30% above baseline value reduced MI size. A minimum duration of 3 minutes was necessary to induce the protective effects.  相似文献   
35.
Nutcracker syndrome (NCS) is a rare pathology manifested by pain or hematuria in males and females alike. It can be easily overlooked, and should be considered in young men or women with symptoms of extended duration. We present a case of a 54-year-old female with chronic lower abdominal pain radiating to the left thigh of 4 years in duration. Computed tomography (CT) eventually revealed engorged left renal, gonadal, and uterine veins due to compression between the superior mesenteric artery (SMA) and the abdominal aorta, consistent with NCS. After a successful endovascular stenting and a 6-month period of antiplatelet and anticoagulant therapy, the patient returned to stable health. NCS, while rare, should be suspected in patients of both sexes with persistent pain or hematuria.  相似文献   
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Chronic lymphocytic leukemia is one of the most common leukemias in the western world and consists of many chromosome aberrations. We report the case of a 74-year-old male patient with chronic lymphocytic leukemia with complex variant translocations t(8;22)(q24;q11) and der(8)t(6;8)(p21;p21) identified by chromosome banding analysis and confirmed by fluorescence in situ hybridization analysis of interphase cells. Because of the rarity of these changes, possible molecular mechanisms associated with this karyotype are discussed.  相似文献   
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