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221.
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223.
M. S. Lima F. Kallfelz L. Krook P. W. Nathanielsz 《Calcified tissue international》1993,52(4):283-290
Summary The objective of this study was to evaluate the effects of a long-term, low-calcium diet on fetal calcium metabolism and fetal
skeleton skeleton development in ewes. Eleven pregnant sheep were assigned to two groups, fed either a diet low in calcium
(0.26% total dry matter) or normal in calcium (0.8% total dry matter) for 2 months, starting at 60 days gestational age. The
ewes fed the low calcium diet showed lower plasma levels of calcium and higher plasma levels of hydroxyproline, parathyroid
hormone, and 1,25 (OH)2D compared with the ewes fed the normal calcium diet. There were no differences in these variables between the two groups
of fetuses. These observations suggest that the plasma components of calcium homeostasis measured in the fetal lamb in the
present study are independent of the ewe and are not significantly affected by the presence of lowere maternal calcium for
many weeks during pregnancy. Despite the ability of the fetus of the ewe on the low calcium diet to maintain relatively normal
circulating plasma components of calcium homeostasis, long-term maternal hypocalcemia delayed fetal skeletal ossification
as shown by histological examination of the fetal humerus. The fetal humerus from low calcium-fed ewes showed a lower proportion
of bone versus cartilage (45.6±5.9 versus 57.4±4.6%, mean ±SD) lower ash content (15.4±1.5 versus 17.4±1.0%), and lower specific
gravity (1.19±0.2 versus 1.22±0.02) (P<0.05) than the humerus from fetuses of normal calcium-fed ewes. This study shows that the long-term calcium intake of the
ewe does affect fetal skeletal development, despite a lack of observable effects on fetal plasma concentrations of calcium
or known calcium regulating hormones such as 1,25(OH)2D or parathyroid hormone. 相似文献
224.
P. Mildenberger H. U. Kauczor Katja Ehrhard W. Schmiedt M. Thelen 《Der Radiologe》1997,37(11):883-890
Purpose: Prospective evaluation of the accuracy of CT angiography (CTA) with different postprocessing for extracranial carotid artery
in comparison with DSA.
Method: one hundred patients were studied with standarized CTA. For postprocessing, MPR, MIP, and 3D reconstruction based on segmentation
with upper and lower threshold were used. Intravascular density profiles were considered. All CTA studies were correlated
with intra-arterial angiography. The degree and classification of stenoses was determined using the guidelines established
by the NASCET collaborators.
Results: Measurement of stenosis was possible by MPR in 82.5 %, by MIP in 85 %, and 3D in 100 %. Correct classification was found
in 65.5 % for MPR, 66 % for MIP and 88.5 % for 3D. The sensitivity for severe stenoses was 74 % for MPR, 82 % for MIP, and
93 % for 3D. The specificity of these methods was 98 %, 96 %, and 97 %, respectively. All carotid occlusions were correctly
identified, no carotid artery was wrongly classified as occluded.
Conclusions: CT angiography allows reliable examinations in carotid artery stenoses and occlusions. 3D reconstruction based on threshold
segmentation is superior to MPR and MIP. In some circumstances, e.g., carotid occlusion, further investigation by invasive
procedures is not necessary.
相似文献
225.
226.
微量元素锌在佝偻病治疗中的效果观察 总被引:7,自引:1,他引:6
目的 :探讨补充锌 +维生素D +钙剂治疗佝偻病的效果。方法 :随机分为 3组 ,每组各 5 3例。对照组给予常规治疗 (即维生素D +钙剂 ) ,治疗 1组先给予锌治疗 1个月后 +常规治疗 ,治疗 2组同时给予锌 +常规治疗。 3个月为 1疗程。治疗前后检测血清微量元素及骨碱性磷酸酶 (BALP)等项目。结果 :治疗 1、2组疗效好于对照组 ,差异非常显著 (P <0 0 1) ;治疗1组疗效好于治疗 2组 ,差异有显著性 (P <0 0 5 )。结论 :治疗大多数伴低锌的佝偻病先补锌 1个月 ,再加常规治疗 ,疗效更佳。 相似文献
227.
Nobutaka Eiraku Shinji Ijichi Shinji Yashiki Mitsuhiro Osame Shunro Sonoda 《Journal of neuroimmunology》1992,37(3):223-228
The in vitro proliferation of peripheral blood lymphocytes (PBLs) without any mitogenic stimulation is one of the hallmarks of human T lymphotropic virus type I (HTLV-I) infection. Recent evidence suggests a difference in the degree of the phenomenon between HTLV-I-associated myelopathy/tropical spastic paraparesis (HAM/TSP) and asymptomatic HTLV-I carriers (AC). In this article, we demonstrated several alterations in the features of the in vitro transformed lymphocytes between patients with HAM/TSP (n = 16) and AC (n = 8). The percentages of total CD8+ and CD8+CD28+ cells were significantly increased in the in vitro proliferating T lymphocytes derived from the patients with HAM/TSP when compared to those from AC. HAM/TSP was segregated from AC by the high degree of the proliferation of CD8+CD28+ cells. The expression of HTLV-I-specific antigens on the cultured PBLs was detected only in the subjects which showed low CD8+CD28+/CD4+ ratio of the in vitro proliferating lymphocytes. These findings suggest that this phenomenon distinguishes HAM/TSP from AC, not only in quantity but also in quality. 相似文献
228.
杜国有 《中华流行病学杂志》1994,15(5):278-281
笔者应用ELISA法对广西百色地区179例各类肝病患者及41例受血者血清进行了抗-HCV检测。结果各类肝病抗-HCV阳性率为17.9%,受血者抗-HCV阳性率为31.7%。在急性肝炎(急肝)、慢性肝炎(慢肝)、肝硬化和肝癌中,抗-HCV阳性率各为4.3%(1/23)、12.8%(10/78)、28.6%(12/42)和25.0%(9/36)。抗-HCV阳性率有随肝病慢性比而增高的趋势,肝硬化的抗-HCV阳性率明显高于急肝或慢肝(P<0.05),而肝癌的抗-HCV阳性率与急肝或慢肝相差不显著(P>0.05或0.1),且发现HBsAg阴性肝病者的抗-HCV阳性率明显高于HBsAg阳性患者(P<0.5),肝病患者抗-HCV的检出率与ALT活性无关(P>0.05)。在受血者中,抗-HCV的检出率与受血次数、ALT活性关系非常密切。因此,加强对HCV的检测是当前预防输血后肝炎的紧迫任务。 相似文献
229.
用动物肠道溶瘤病毒(Ecco-18)实验治疗荷瘤小鼠(P_(615))时,对其非瘤器官进行了光镜和电镜观察。结果发现,荷瘤小鼠各脏器均未查到病毒颗粒或病毒性物质。各脏器的超微结构与对照组相比未见病理改变。 相似文献
230.
采用ELISA法及逆转录—PCR(简称RT—PCR)法检测36例非甲—戊型肝炎患者血清庚型肝炎病毒抗体(简称抗HGV)和庚型肝炎病毒(简称HGVRNA)。结果:7例(19.4%)抗HGV阳性,2例(5.4%)同时HGVRNA阳性;急性肝炎抗HGV阳性者临床表现与抗HGV阴性者无显著差异,慢性肝炎抗HGV阳性者较抗HGV阴性者轻。提示:HGV可引起急、慢性肝炎,在非甲—戊型肝炎中占有一定比例,但不是主要原因。 相似文献