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IPS Empress 2全瓷修复的临床特点 总被引:1,自引:0,他引:1
陈亚琴 《国际口腔医学杂志》2001,28(3):198
全瓷材料可以提高前牙修复体的自然、逼真效果,它克服了金瓷修复体不透光、颈缘效果差的缺点。但全瓷材料的挠曲性能低,且不能承受过大的抬力,因此仅限于一个单位的修复。最近一种新的全瓷材料(IPS Empress2)由于强度高,可用于前牙多个单位桥的修复,它具有极好的美观性能,高度半透明,边缘完整,它的可蚀刻性增加了与牙齿的粘接, 相似文献
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The inappropriate expression of c-myc in cells deprived of growth factors has recently been implicated in the activation of programmed cell death (apoptosis). The studies described here examine the ability of interleukin-3 (IL-3) or erythropoietin (Epo) to suppress apoptosis that occurs in association with enforced myc expression during cell cycle arrest of a murine IL-3-dependent myeloid progenitor cell line, 32D. G1 arrest was observed when culturing 32D cells to high density in medium supplemented with IL-3, or at subconfluent densities in medium supplemented with Epo. Under both conditions, endogenous c-myc expression was downregulated and viability was maintained. In clones of cells in which c-myc is constitutively expressed from a retroviral vector, enforced c-myc expression was associated with the activation of apoptosis at high cell densities. Similarly, enforced c-myc expression was deleterious to cell survival when these cells were cultured in Epo, as apoptosis was evident within 6 hours. The results support the concept that inappropriate c-myc expression activates apoptosis and that neither IL-3 nor Epo can suppress this program under these conditions. 相似文献
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Anderson RA; Evans LW; Irvine DS; McIntyre MA; Groome NP; Riley SC 《Human reproduction (Oxford, England)》1998,13(12):3319-3325
Follistatin is a binding protein for the activin and inhibin family of
hormones, regulating their biological activity. In the male reproductive
tract, the interaction of these factors is likely to be involved in the
regulation of the proliferation of several cell types. We have investigated
the presence of follistatin and activin A in seminal plasma using specific
immunoassays and have localized follistatin and activin/inhibin subunits in
the adult human testis, prostate and seminal vesicle to establish their
likely sources. High concentrations of immunoreactive follistatin were
present in seminal plasma in normal men (mean 97.9 ng/ml; 1.43 ng/ml in
peripheral plasma) and were similar in men with oligo/azoospermia and
following vasectomy. Follistatin immunoreactivity was localized to both
Leydig and Sertoli cells of the testis, and to epithelial cells of the
prostate gland and seminal vesicle, which are likely to be the predominant
sources of the hormone in seminal plasma. Activin A was also present in
seminal plasma in normal men but was undetectable following vasectomy, thus
deriving from the testis. Consistent with this finding, the betaA-subunit
was immunolocalized in Sertoli and Leydig cells but was not present in
seminal vesicle or prostate gland. The functional significance of the high
concentrations of follistatin secreted into seminal plasma by the prostate
gland and/or seminal vesicle is uncertain, but they may regulate the
biological activity of testis-derived activin A and inhibin B.
相似文献
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DS Chadha A Swamy SK Malani RK Ganjoo OP Mathew 《Medical Journal Armed Forces India》2009,65(3):203-207
Background
Obesity is associated with increased cardiovascular morbidity and mortality. A direct effect of isolated obesity on cardiac function is not well established. The study was designed to determine the direct effect of various grades of isolated obesity on echocardiographic indices of systolic and diastolic left ventricular function.Methods
Fifty one obese and 25 normal weight, serving personnel without any other pathological condition were studied. Group I (n=25) consisted of subjects with normal weight and body mass index (BMI <25kg/m2), Group II (n=34) of overweight subjects (BMI 25-29.9 kg/m2) and Group III (n=17) of obese subjects (BMI >30 kg/m2). Echocardiographic indices of systolic and diastolic function were obtained and dysfunction was assumed when at least two values differed by ≥ 2 SD from the normal weight group.Result
Ejection fraction, fractional shortening were increased (p<0.05) in Group II and III. Left ventricular dimensions were increased (p< 0.001) but relative wall thickness was unchanged. Systolic dysfunction was not observed in any of the obese patients. The mitral valve pressure half time (p< 0.01), left atrial diameter (p < 0.01) and the deceleration time were increased (p< 0.01) in obese subjects, while other diastolic variables were unchanged. No difference were found between obesity subgroups. Subclinical diastolic dysfunction was more prevalent among obese subjects. BMI correlated significantly with indices of left ventricular systolic and diastolic function.Conclusion
Subclinical left ventricular diastolic dysfunction was noted in all grades of obesity which correlates with BMI.Key Words: Obesity, Systolic function, Diastolic function, Echocardiography 相似文献109.
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