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51.
保定地区1934年首次经血清学证实有EHF病例发生,并从疫区鼠类中查到EHF抗原,其阳性率分别为:褐家鼠4.85%,黑线姬鼠1.95%,大仓鼠0.79%,小家鼠0.51%,褐家鼠可能是我区的主要传染源。疫区健康人群血清EHF抗体阳性率为1.37%,女性显著高于男性。 相似文献
52.
Summary. In recent years the continuity equation has been established as a valuable non-invasive method for calculating aortic valve area. The continuity equation cannot be used if there is calcification or sub-valvular stenosis in the left ventricle-outflow tract, because the area of the outflow trace is not circular in those cases. The authors have tested the value of a non-invasive variant of the Gorlin formula, as an alternative method of identifying severe aortic stenosis. They examined 32 consecutive patients with aortic stenosis with both methods. Seventeen patients had severe stenosis (valve area^0–7 cm2), calculated by the continuity equation. The other 15 patients had moderate stenosis (valve area 0–7–1–0 cm2). Using the non-invasive variant of the Gorlin formula, the authors were able to identify 16 of the 17 cases with severe stenosis, thus showing that the method is useful for identifying severe aortic stenosis. (P<0–001 by x2-test). 相似文献
53.
对AF系统整复压缩爆裂骨折椎体高度及椎管横截面的观测 总被引:4,自引:3,他引:1
目的 :量化评价AF系统恢复胸腰段压缩爆裂椎体高度椎管截面积的效果。方法 :测量AF系统治疗的 72例胸腰段压缩爆裂骨折术前后影像。统计椎体前后缘高度、Cobb角、椎管截面积资料。结果 :术后伤椎前缘高度恢复至 ( 96.5± 2 .3 ) %后缘高度恢复至 ( 98.2± 0 .9) % ,Cobb角恢复至 ( 5 .4± 1.5 )° ,椎管截面积恢复至 ( 97.2± 2 .1% ) ,各项指标与术前比较有非常显著性差异 (P <0 .0 0 1)。术后随访 0 .5~ 3 .5年 ,神经功能按Frankel评定 :60例提高 1~ 3级。结论 :AF系统能恢复或基本恢复胸腰段压缩爆裂骨折椎体的前后缘高度、Cobb角、椎管容积 ,为脊髓神经功能的恢复提供一个良好的环境。是治疗脊柱胸腰段压缩爆裂骨折较好的内固定器。 相似文献
54.
55.
Katsuyoshi Hori Maroh Suzuki Shigeru Tanda Sachiko Saito Mika Shinozaki Qiu-Hang Zhang 《Cancer science》1991,82(11):1309-1316
To elucidate the significance of angiotensin II (AID-induced hypertension chemotherapy, changes of tissue blood flow both in normal subcutis and in tumors (AH109A, LY80) were measured with the hydrogen gas clearance method. A newly-developed anesthetic machine was used to keep the animals' condition constant. Tissue blood flow in normal subcutis and tumors always fluctuated with time under normotension. The nature and the rate of fluctuation in tumor Wood flow were almost identical in two different types of tumors. However, the fluctuation of blood flow in tumor and that in normal subcutis were almost always inversely related when blood flows in these different tissues were measured simultaneously, i.e., when tissue blood flow in normal subcutis decreased, tumor blood flow increased, and vice versa. The findings supported the idea that the connection mode between the tumor vascular bed and normal vascular bed is a parallel circuit. Vascular resistance in the normal vascular bed under All-induced hypertension seemed to be greater than that under normotension, because the All-increased tumor blood flow always exceeded the maximum tumor blood flow under normotension. Due to the fluctuations of tumor blood flow, no-flow or low-flow areas, resistant to delivery of anti-cancer drugs, moved sporadically within the tumor under the normotensive condition. However, good conditions for drug delivery to tumor tissue were induced by All-induced hypertension. 相似文献
56.
娄耀君 《华北煤炭医学院学报》2002,4(3):284-285
(1)目的 探讨鼻内窥镜下Nd:YAG激光治疗变应性鼻炎的方法。(2)方法 应用鼻内镜下Nd:YAG激光凝固中务甲前1/3端治疗变应性鼻炎126例。(3) 结果 随访1年,显效109例(86.5%),有效13例(10.3%),无效4例(3.2%),总有效率96.8%。(4)结论 鼻内镜下Nd:YAG激光凝固中鼻甲前1.3端治疗变应性鼻炎,具有视野清楚,操作简便,疗效好等优点,值得临床应用。 相似文献
57.
目的 了解中缅边境一线县、二线县、及一线三个县的一线自然村、二线自然村的疟疾流行情况,为制定边境地区疟疾防治措施提供科学依据。方法 采用IFAT对中缅边境沧源、耿马及孟连一线县与双江县、永德县二线县,边境线3县一线自然村和二线自然村进行疟血清流行病学调查,用电脑软件EPI6X2检验法进行数据分析。结果一线县抗体阳性率23.88%(568/2379),二线县抗体阳性率1.40%(10/712),一线县显著高于二线县(x2=180.54;P<0.01)。一线县的一线自然村抗体阳性率33.05%(467/1413),二线自然村抗体阳性率10.46%(101/966),一线自然村显著高于二线自然村(x2=159.92;P<0.01)。结论IFAT抗体阳性率和阳性GMRT说明靠近边境地带比远离边境的地带疟疾流行更为严重。应加强出入境人员的防治工作,才能控制边境疟病流行。 相似文献
58.
Variability in hand surface representations in areas 3b and 1 in adult owl and squirrel monkeys 总被引:4,自引:0,他引:4
M M Merzenich R J Nelson J H Kaas M P Stryker W M Jenkins J M Zook M S Cynader A Schoppmann 《The Journal of comparative neurology》1987,258(2):281-296
Detailed microelectrode maps of the hand representation were derived in cortical areas 3b and 1 from a series of normal adult owl and squirrel monkeys. While overlap relationships were maintained, and all maps were internally topographic, many map features varied significantly when examined in detail. Variable features of the hand representations among different monkeys included a) the overall shapes and sizes of hand surface representations; b) the actual and proportional areas of representations of different skin surfaces and the cortical magnifications of representations of specific skin surfaces, which commonly varied severalfold in area 3b and manyfold in area 1; c) the topographic relationships among skin surface representations, with skin surfaces that were represented adjacently in some monkeys represented in locations many hundreds of microns apart in others; d) the internal orderliness of representations; e) the completeness of representations of the dorsal hand surfaces; and f) the skin surfaces represented along the borders of the hand representation. Owl monkey maps were, in general, internally more strictly topographic than squirrel monkey maps. In both species, area 3b was more strictly topographic and less variable than was area 1. The degree of individual variability revealed in these experiments is difficult to reconcile with the hypothesis that details of cortical maps are ontogenetically specified during a period in early life. Instead, we propose that differences in the details of cortical map structure are the consequence of individual differences in lifelong use of the hands. This conclusion is consistent with earlier studies of the consequences of peripheral nerve transection and digital amputation, which revealed that cortical maps are dynamically maintained and are alterable as a function of use or nerve injury in these monkeys (Merzenich et al., '83a,b, '84a; Merzenich, '86; Jenkins et al., '84; Jenkins and Merzenich, '87). 相似文献
59.
W. B. Spatz R.-B. Illing D. M. Vogt Weisenhorn 《The Journal of comparative neurology》1994,339(4):519-534
The anatomical distributions of the mitochondrial enzyme cytochrome oxidase (CO) and of the calcium binding protein parvalbumin (PV) were studied in the striate cortex of adult and neonate New World monkeys (Callithrix jacchus). In the adult marmoset, both proteins were found in laminar arrangements similar to those described for the macaque monkey, with prominent bands of PV-like immunoreactive (PV-LI) puncta in layers IV and IIIb, and fairly evenly distributed PV-LI nonpyramidal neurons. Furthermore, the pattern of CO activity in area 17 of the neonate marmoset was almost identical to the CO pattern described in neonate macaque and squirrel monkeys. It came, therefore, as a surprise to find that the adult pattern of PV-like immunoreactivity (PV-LI) in the marmoset striate cortex arises from a neonatal pattern strikingly different from that seen in any developmental stage of the macaque, or in any other mammal studied so far. In the deep layers IV through VI of the neonate marmoset, a large number of PV-LI neurons was stained in bandlike patterns, their number in layers IV and V exceeding the number of PV-LI neurons present in these layers of the adult marmoset area 17. Staining of layers IV and VI was restricted to area 17 and involved nonpyramidal cells and their exceeding the number of PV-LI neurons present in these layers of the adult marmoset area 17. Staining of layers IV and VI was restricted to area 17 and involved nonpyramidal cells and their processes. The stained band of layer V, in contrast, continued throughout most of the neocortex. In area 17, an estimated 10 to 20% of the stained cells in layer V exhibited pyramidal shapes. The findings show that the expression of PV by visual cortical cells occurs before birth and suggest that the comparatively early onset of PV expression is not dependent on the onset of textured vision. The exuberant number of stained cells in some layers, and particularly the staining of pyramidal cells, in the neonate marmoset, suggest that a considerable number of cells possesses the stainability for PV-LI only transiently, i.e., in the marmoset, these cells have a specific demand for parvalbumin during this phase of their development. © 1994 Wiley-Liss, Inc. 相似文献
60.
Estrogenic Induction of NADPH- Diaphorase Activity in the Preoptic Neurons Containing Estrogen Receptor Immunoreactivity in the Female Rat 总被引:1,自引:0,他引:1
Nitric oxide and estrogen have been shown to play a critical role in the control of female reproductive function. In order to determine an anatomical relationship between nitric oxide generating neurons and estrogen target neurons, NADPH-diaphorase histochemistry was combined with estrogen receptor immunohistochemistry in the female medial preoptic area. While only a few weakly stained neurons for NADPH-diaphorase were found in ovariectomized control rats, a drastic increase in NADPH-diaphorase activity was observed in the medial preoptic nucleus of estradiol-treated ovariectomized animals. The total number of NADPH-diaphorase neurons in the estradiol-treated group increased three-fold relative to controls, and more than 80% of those neurons contained estrogen receptor-immunoreactivity in their nuclei. Since neuronal NADPH-diaphorase is nitric oxide synthase, the present result suggests that nitric oxide synthase activity can be positively regulated by estradiol in neurons containing estrogen receptor in the female medial preoptic nucleus. 相似文献