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71.
Setsuko Tohno Yoshiyuki Tohno Takeshi Minami Yuko Okazaki Masako Utsumi Fumio Nishiwaki Yumi Moriwake Masa-oki Yamada 《Biological trace element research》1998,62(1-2):17-23
To elucidate age-related changes of mineral contents in human veins, the relative contents (RCs) of elements in the human
internal jugular veins, superior and inferior venae cavae, and femoral veins from 27 subjects ranging from 40 to 98 yr old
were analyzed by inductively coupled plasma atomic emission spectrometry.
The average RCs of calcium in the 27 specimens were the highest in the internal jugular vein, followed in descending order
by the superior vena cava, femoral vein, and inferior vena cava.
The RCs of calcium and phosphorus in the internal jugular veins started to increase after the age of 50 yr, became the highest
in subjects in their 60s and thereafter decreased gradually. It is noted that such accumulations of minerals, similar to the
internal jugular vein, were also found in the veins, such as the superior and inferior venae cavae, and femoral vein. Accumulation
of minerals in the veins is different from that of arteries, which increase progressively by aging, but do not decrease. 相似文献
72.
Hypoplastic defects of tooth enamel and Harris lines in the long bones have been heralded as potentially useful indicators of health conditions in prehistoric populations. Both result from temporary cessation of growth processes due to similar types of disease, malnutrition, or other metabolic insult. An association test for the first six years of life was conducted on a large series of prehistoric California Indians, using femora and canines from young adults. No significant association was found. This is ascribable to differences in etiology and stability. 相似文献
73.
Darius Ansari Poulami P Borkar Patricia L Davis Frederick T Collison Niamh Wynne Nicole Zangler Gerald A Fishman Joseph Carroll Xincheng Yao Michael A Grassi 《Experimental biology and medicine (Maywood, N.J.)》2021,246(20):2202
A pathognomonic macular ripple sign has been reported with scanning laser ophthalmoscopy images in patients with foveal hypoplasia, though the optical basis of this sign is presently unknown. Here we present a case series of seven individuals with foveal hypoplasia (based on spectral domain optical coherence tomography). Each patient underwent infrared scanning laser ophthalmoscopy retinal imaging in both eyes, acquired with and without a polarization filter and assessment for a ripple-like effect in the fovea. On imaging, macular ripples were present in all eyes with foveal hypoplasia when using a polarization filter, but not when imaged without the filter. We conclude that the macular ripple sign is an imaging artifact attributable to the unique pattern of phase retardation of the Henle fiber layer in the setting of foveal hypoplasia. By utilizing a polarization filter with retinal photography, this feature can be exploited to promptly identify foveal hypoplasia in settings where OCT is not possible due to nystagmus. 相似文献
74.
Debbie Guatelli-Steinberg John R. Lukacs 《American journal of physical anthropology》1998,107(2):179-186
Three hundred and sixty rhesus macaque specimens at the Caribbean Primate Research Center were examined for evidence of linear enamel hypoplasia (LEH). A previously unreported intertooth pattern in LEH was observed. Defects occur preferentially on the sectorial premolar of both males and females. Relative to other teeth, the sectorial premolar exhibits more prominent defects and is more likely to exhibit multiple defects. This pattern is unlike the human intertooth LEH pattern and unlike patterns previously reported for monkeys and apes. These observations are discussed in the context of factors thought to influence the intertooth distribution of LEH in humans and in nonhuman primates. The authors reject crown height, the timing of crown development, and the duration of crown formation as factors contributing to the observed pattern and favor an explanation involving enamel thickness, perikymata spacing, and/or prism orientation. Am J Phys Anthropol 107:179–186, 1998. © 1998 Wiley-Liss, Inc. 相似文献
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Four aspects of enamel hypoplasia of the maxillary central incisor and mandibular canine (hypoplasia presence, width, cumulative width, and crown position) were correlated with directional and fluctuating measures of bilateral odontometric asymmetry in a large panel (n = 950) of South Australian twins. Hypoplasia and asymmetry are thought to reflect general developmental disruption, but they show few correlations beyond the expected statistical type I error. This may relate to differences in their specific etiology, the composite nature of overall crown dimensions, a general lack of stress, and the extended period of formation of dental crowns. In contrast, asymmetry is marginally more detectable in a subsample separated according to hypoplastic teeth, suggesting that correspondence may be clearer in comparisons at the population rather than individual level. The most notable difference is the greater variability of asymmetry measures in hypoplastic individuals. 相似文献
78.
The nephric duct plays a central role in orchestrating the development of the mammalian urogenital system. Lim 1 is a homeobox gene required for head and urogenital development in the mouse but most Lim 1-deficient embryos die by embryonic day 10. To determine the role of Lim 1 in the development of the nephric duct, we conditionally removed Lim 1 in the nephric epithelium just after the nephric duct begins to form using a floxed allele of Lim 1 and Pax2-cre transgenic mice. We report that Lim 1 conditional knockout mice have renal hypoplasia and hydronephrosis. Developmental studies revealed that the caudal portion of the nephric duct did not reach the urogenital sinus at embryonic day 10.5, formation of the ureteric bud was delayed, the ureteric bud was smaller and branching of the ureteric bud reduced. We also found that the nephric duct was generally not maintained and extension of the Müllerian duct inhibited. Molecular analysis indicated that Pax2 was expressed normally but the expression of Wnt9b and E-cadherin in the nephric duct was markedly altered. These results suggest that Lim 1 influences nephric duct extension and ureteric bud outgrowth by regulating and or maintaining the differentiation of the nephric epithelium. 相似文献
79.
比较股动脉注射与静脉滴注两法给予复方抗栓确治疗下肢动脉闭性疾病的疗效。方法101例患者随机分成股动脉注射与静脉滴注复方抗栓酶两组。结果显效率股动脉组62.3%,静脉组41.7%。结论复方抗栓酶股动脉注射治疗下肢动脉闭塞性疾病的疗效明显优于静脉滴注(P<0.01)。 相似文献
80.
Femoral perfusion after pulsed electromagnetic field stimulation in a steroid‐induced osteonecrosis model 下载免费PDF全文