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81.
Toda K Mackenzie K Mehra MR DiCorte CJ Davis JE McFadden PM Ochsner JL White C Van Meter CH 《The Annals of thoracic surgery》2002,74(6):2082-7; discussion 2087
BACKGROUND: We sought to determine the optimal approach to revascularization of patients with severe left ventricular (LV) dysfunction. METHODS: We conducted a single-center observational study of 117 consecutive patients who had severe LV dysfunction (15% < OR = LV ejection fraction < OR = 30%) and underwent either coronary artery bypass grafting (CABG, n = 69) or percutaneous revascularization (n = 48) between 1992 and 1997. RESULTS: The CABG group was younger (62 versus 67 years, p = 0.026), and fewer previous bypasses (7% versus 40%, p < 0.0001) and fewer prior percutaneous revascularizations (16% versus 42%, p = 0.0019) were noted. More vessels were revascularized (3 +/- 0.8 versus 1.5 +/- 0.7, p < 0.0001), and revascularization was more complete by CABG (84% versus 48%, p < 0.0001). Morbidity and mortality at 30 days were similar, and there was no significant difference in 3-year survival (73% versus 67%), although 3-year cardiac event-free survival (52% versus 25%, p = 0.0011) and 3-year target vessel revascularization-free survival (71% versus 41%, p < 0.0001) were significantly better in the CABG group, and LV ejection fraction was significantly improved after CABG. In the subgroup of patients 65 years of age or older and those without proximal left anterior descending coronary artery lesions, significant benefit of CABG in cardiac event-free and target vessel revascularization-free survival disappeared. CONCLUSIONS: We found that in clinically selected patients with severe ventricular dysfunction, CABG compared with percutaneous revascularization achieves more complete revascularization, improved LV function, fewer cardiac events, and fewer target vessel revascularizations, but does not affect mid-term survival. A prospective controlled trial with defined criteria for treatment assignment is warranted to confirm our results regarding the two revascularization strategies in patients with severe LV dysfunction. 相似文献
82.
Koichi Toda MD PhD Karen Mackenzie MD Mandeep R. Mehra MD Charles J. DiCorte MD James E. Davis MD P. Michael McFadden MD John L. Ochsner MD Christopher White MD Clifford H. Van Meter Jr MD 《The Annals of thoracic surgery》2002,74(6):168-2087
Background
We sought to determine the optimal approach to revascularization of patients with severe left ventricular (LV) dysfunction.Methods
We conducted a single-center observational study of 117 consecutive patients who had severe LV dysfunction (15% ≤ LV ejection fraction ≤ 30%) and underwent either coronary artery bypass grafting (CABG, n = 69) or percutaneous revascularization (n = 48) between 1992 and 1997.Results
The CABG group was younger (62 versus 67 years, p = 0.026), and fewer previous bypasses (7% versus 40%, p < 0.0001) and fewer prior percutaneous revascularizations (16% versus 42%, p = 0.0019) were noted. More vessels were revascularized (3 ± 0.8 versus 1.5 ± 0.7, p < 0.0001), and revascularization was more complete by CABG (84% versus 48%, p < 0.0001). Morbidity and mortality at 30 days were similar, and there was no significant difference in 3-year survival (73% versus 67%), although 3-year cardiac event-free survival (52% versus 25%, p = 0.0011) and 3-year target vessel revascularization-free survival (71% versus 41%, p < 0.0001) were significantly better in the CABG group, and LV ejection fraction was significantly improved after CABG. In the subgroup of patients 65 years of age or older and those without proximal left anterior descending coronary artery lesions, significant benefit of CABG in cardiac event-free and target vessel revascularization-free survival disappeared.Conclusions
We found that in clinically selected patients with severe ventricular dysfunction, CABG compared with percutaneous revascularization achieves more complete revascularization, improved LV function, fewer cardiac events, and fewer target vessel revascularizations, but does not affect mid-term survival. A prospective controlled trial with defined criteria for treatment assignment is warranted to confirm our results regarding the two revascularization strategies in patients with severe LV dysfunction. 相似文献83.
McFadden D 《Archives of sexual behavior》2002,31(1):99-111
Otoacoustic emissions (OAEs) and auditory evoked potentials (AEPs) are different in several special populations of subjects. For females having opposite-sex co-twins (OSDZ females) and for homosexual and bisexual females, OAEs are masculinized. Certain AEP measures from homosexual and bisexual females also are masculinized. Certain AEP measures from homosexual males are hypermasculinized. These and other facts can be explained by assuming that these special populations received greater-than-normal exposures to androgens at some point(s) during development, possibly during prenatal development. It is proposed that some differences in androgenization may have been spatially and temporally localized rather than global, and that the localized response to androgen exposure sometimes may be nonmonotonic. 相似文献
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85.
Neurons containing gamma aminobutyric acid (GABA) are widely distributed throughout the primary auditory cortex (AI). We investigated the effects of endogenous GABA by comparing response properties of 110 neurons in chinchilla AI before and after iontophoresis of bicuculline, a GABA(A) receptor antagonist, and/or CGP35348, a GABA(B) receptor antagonist. GABA(A) receptor blockade significantly increased spontaneous and driven discharge rates, dramatically decreased the thresholds of many neurons, and constricted the range of thresholds across the neural population. Some neurons with 'non-onset' temporal discharge patterns developed an onset pattern that was followed by a long pause. Interestingly, the excitatory response area typically expanded on both sides of the characteristic frequency; this expansion exceeded one octave in a third of the sample. Although GABA(B) receptor blockade had little effect alone, the combination of CGP35348 and bicuculline produced greater increases in driven rate and expansion of the frequency response area than GABA(A) receptor blockade alone, suggesting a modulatory role of local GABA(B) receptors. The results suggest that local GABA inhibition contributes significantly to intensity and frequency coding by controlling the range of intensities over which cortical neurons operate and the range of frequencies to which they respond. The inhibitory circuits that generate nonmonotonic rate-level functions are separate from those that influence other response properties of AI neurons. 相似文献
86.
Polk HC Bowden TA Rikkers LF Balch CM Organ CH Murie JA Pories WJ Buechler MW Neoptolemos JP Fazio VW Schwartz SI Cameron JI Kelly KA Grosfeld JL McFadden DW Souba WW Pruitt BA Johnston KW Rutherford RB Arregui ME Scott-Conner CE Warshaw AL Sarr MG Cuschieri A Tompkins RK MacFadyen BV 《Annals of surgical oncology》2002,9(5):421-422
87.
目的使用非线性成长率理论分析人眼视力发展规律。方法使用高斯光学及成像方程推导出两个参数:屈光状态改变率(M)及眼轴成长率(N),用以预测MOS(初始近视)、年龄(A^*)及其后视力的发展情况。结果当有效焦距F=(21-22)、密码M=(2.67—2.9)(D/mm)时,此计算值符合实验平均值(2.7)。当年龄A^*=(3,6)岁的屈光度变化已知时,我们计算其MOS预测年龄为A^*=(7.3,21.8)岁(在不同条件下)。此值反比于M值在A=6及A=3的比值或N=N—N^*,即非正视态及正视态的眼轴成长率之差。本理论也可用来预测在年龄A=25时的近视度,分别为D=-14及-0.49的上述两例情况,同时也能分析Lain等人的测量值(由出生到青年期的视力发展情况)。结论本理论可预测MOS、其后发展情况及其符合实验值(M)。使用成长率差值(dN)比使用L/rl比值能更准确地预测MOS。 相似文献
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89.
90.
Towfigh S McFadden DW Cortina GR Thompson JE Tompkins RK Chandler C Hines OJ 《The American surgeon》2001,67(1):7-10
The surgical management of porcelain gallbladder is based on studies performed in 1931 and 1962, which indicated a correlation between porcelain gallbladder and carcinoma. We sought to evaluate the characteristics of patients with porcelain gallbladder and the risk for gallbladder carcinoma. The medical records of 10,741 cholecystectomies performed between 1955 and 1998 were reviewed and recorded. The pathology slides were evaluated for evidence of calcification and gallbladder carcinoma. Fifteen (0.14%) of 10,741 specimens were porcelain gallbladders. Ten patients (67%) had symptoms suggestive of biliary colic or cholecystitis. Five (33%) were asymptomatic and diagnosed incidentally. All specimens demonstrated chronic cholecystitis and partial calcification of the gallbladder wall. Nine (60%) had cholelithiasis. None had gallbladder carcinoma by recent review of pathologic material. During this same period 88 (0.82%) patients had gallbladder carcinoma, none of which showed calcification of the wall. This report represents the largest modern review of porcelain gallbladders. No carcinoma was identified among patients with porcelain gallbladder. In addition no patient with gallbladder carcinoma had calcified gallbladder. With a better understanding of the natural history of the porcelain gallbladder the current management of these patients may change. 相似文献