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91.
92.
观察硒和维生素A(VA)对支原体肺炎的治疗效果.方法 采用双盲随机对照2×2析因实验设计,选择100例住院支原体肺炎患儿,分为补硒组26例,补VA组23例,补硒和VA组30例以及病例对照组21例,正常组21例.一次补硒量为1mg亚硒酸钠和/或15万单位VA,对照病例组给予常规治疗.结果 与对照组比,治疗后3个补充组的症状和体征缓解天数均有不同程度缩短(P<0.05),补硒组白细胞硒和谷胱甘肽过氧化物酶水平显著上升(P<0.05),补VA、补硒组血清VA水平上升(P<0.01),细胞免疫功能有所改善.结论 硒和VA有协同作用,补充硒或同时加VA,作为辅助治疗支原体肺炎的方法,安全、有效. 相似文献
93.
Reports of the human teratogenicity of retinoids have raised concern about the potential human teratogenicity of high doses of vitamin A. Nevertheless, there are few human case reports of excess intake of vitamin A during pregnancy and defective outcomes. No epidemiological studies have been carried out on this subject. Here we present the results of an epidemiological study of prenatal exposure to high doses of vitamin A in Spain, using data from the Spanish hospital-based, case-control registry. Although it is difficult to reach conclusions with such a very low exposure level (1.3 per 1,000 livebirths), our results suggest that a teratogenic effect might exist for exposures to high doses of vitamin A (OR = 0.5, p = 0.15 for less than 40,000 FU and OR = 2.7, p = 0.06 for 40,000 1U or more). As we might expect, this effect also seems to be related to the organogenetic status (OR = 5.4, p = 0.1 for 1st –2nd month, OR = 1.8, p = 0.4 for 3rd onwards) at the time of exposure. 相似文献
94.
本文报告260例恶性肿瘤患者血清维生素A、E、C水平的测定结果。发现除慢性白血病外,蓁7种恶性肿瘤患者血清维生素A水平平均显著低于健康人(P<0.01);急性白血,肝癌、食管癌患者血清维生素E水平显著低于健康人(P<0.05);急性粒细胞白血病、急性单核细胞白血病、肝癌患者血维生素C水平显著低于健康人(P<0.01)。本研究工作为维生素A、E、C药物在肿瘤临床上的应用提供了参考。 相似文献
95.
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
96.
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
97.
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
98.
核黄素缺乏大鼠红细胞维生素E水平的变化及脂质过氧化关系的研究 总被引:6,自引:0,他引:6
对两组大鼠分别喂饲核黄素缺乏(RD)膳和核黄素添加(R8,22mg/kg饲料)膳8周后,测定了两组大鼠的红细胞维生素E(RBLVe)、红细胞超氧化物歧化酶(SOD)和红细胞丙二醛(MDA)的水平。结果发现:RD组RBCVe水平(4.7173±0.7710mg/g蛋白质)显著低于RS组(5。3868±1.1537mg/g蛋白质,P<0.05)。而RD组的RBCSOD(7745.2±610.1u/g蛋白质)和MDA(0.6868±0.1372μg/g蛋白质)则分别显著低于和高于RS组(8268.5±301.0nu/g蛋白质,0.5548±0.0980,P<0.05)。研究提示,核黄素缺乏引起细胞膜脂质过氧化加重可能RBCVe消耗增加。 相似文献
99.
Enhanced stimulus-reward learning by intra-amygdala administration of a D3 dopamine receptor agonist
The amygdala is considered to be a critical neural substrate underlying the formation of stimulus-reward associations, and
is known to receive substantial innervation from dopaminergic neurons located within the ventral mesencephalon. However, relat-
ively little is known about the function of the mesoamygdaloid dopamine projection in stimulus-reward learning. Recently,
we have found post-session intra-amygdala microinjections of d-amphetamine to enhance appetitive Pavlovian conditioning as assessed in a discriminative approach task. In the present study,
we have examined the effects of dopamine receptor agonists possessing relative selectivity for the D1, D2 and D3 receptor subtypes in order to examine more fully the role of the mesoamygdaloid dopamine projection in stimulus-reward learning.
Thus, subjects were trained to associate an initially neutral stimulus (CS+) with 10% sucrose reward (US). A second, control stimulus (CS−) was also presented but never paired with sucrose reward. In order to measure specifically the conditioned response to CS+/CS− presentation, responding during CS and US presentations was measured separately. Immediately following each training session,
subjects received bilateral intra-amygdala infusion of 0.1, 1 or 10 nmol/side of SKF-38393, quinpirole or 7-OH-DPAT. Infusions
of SKF-38393 or quinpirole were without effect on CS+ approach. However, post-session intra-amygdala infusions of 7-OH-DPAT enhanced selectively CS+ approach in a dose-dependent fashion. No dose of any drug affected CS−approach, US behaviours, or measures of extraneous behaviour. Subsequent acquisition of a novel conditioned instrumental response
was also unaffected. Thus, the present data indicate a selective involvement of the D3 dopamine receptor subtype in the modulation of stimulus-reward learning by the mesoamygdaloid dopamine projection.
Received: 12 December 1996 / Final version: 9 April 1997 相似文献
100.
Simon Vinitski Carlos Gonzalez Feroze Mohamed Tad Iwanaga Robert L. Knobler Kamil Khalili John Mack 《Magnetic resonance in medicine》1997,37(3):457-469
Our aim was to develop an accurate multispectral tissue segmentation method based on 3D feature maps. We utilized proton density (PD), T2-weighted fast spin-echo (FSE), and T1-weighted spin-echo images as inputs for segmentation. Phantom constructs, cadaver brains, an animal brain tumor model and both normal human brains and those from patients with either multiple sclerosis (MS) or primary brain tumors were analyzed with this technique. Initially, misregistration, RF inhomogeneity and image noise problems were addressed. Next, a qualified observer identified samples representing the tissues of interest. Finally, k-nearest neighbor algorithm (k-NN) was utilized to create a stack of color-coded segmented images. The inclusion of T1 based images, as a third input, produced significant improvement in the delineation of tissues. In MS, our 3D technique was found to be far superior to that based on any combination of 2D feature maps (P < 0.001). We identified at least two distinctly different classes of lesions within the same MS plaque, representing different stages of the disease process. Further, we obtained the regional distribution of MS lesion burden and followed its changes over time. Neuropsychological aberrations were the clinical counterpart of the structural changes detected in segmentation. We could also delineate the margins of benign brain tumors. In malignant tumors, up to four abnormal tissues were identified: 1) a solid tumor core, 2) a cystic component, 3) edema in the white matter, and 4) areas of necrosis and hemorrhage. Subsequent neurosurgical exploration confirmed the distribution of tissues as predicted by this analysis. 相似文献