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71.
甲襞、球结膜微循环的应急观测方法是在甲襞、球结膜微循环加权积分综合定量评价方法的基础上,保留权值为4、3的指标,同时观察血管清晰度和红细胞聚集二项指标而形成。同时提供其应急观测积分表、异常分度积分值、诊断标准,并与常规方法进行比较,证明其可以反映绝大部分流态类指标和大部分形态类指标及重要的袢周改变,没有丢失微循环重度异常的信息,保证了重度异常诊断的正确。但在大致正常、轻度异常和中度异常的诊断中应急方法部有判重的倾向,说明应急方法漏掉了一些信息,不能全面地了解微循环的改变,造成了判重的倾向。因此应急方法不能代替常规方法,只能在特定条件下应用。 相似文献
72.
73.
74.
肢端黏液样炎性纤维母细胞肉瘤2例及文献复习 总被引:1,自引:2,他引:1
目的探讨肢端黏液样炎性纤维母细胞肉瘤的临床病理学特征及鉴别诊断。方法对2例发生在下肢末端的黏液样炎性纤维母细胞肉瘤进行光镜观察和免疫组化标记,并复习文献。结果2例发生在下肢末端的病程较长的渐进性肿块,术后局部复发。镜检:病变呈多结节状,边界不清;黏液样基质中见数量不等的各类炎细胞浸润,散在或灶性分布梭形、奇异形和多空泡状脂肪母细胞样3种形态的瘤细胞。免疫表型:肿瘤细胞Vim弥漫阳性,CD68和CD34灶性阳性,CK、SMA、HHF-35、S-100蛋白、CD45、CD45R0、CD15、CD30均阴性。结论此病病程较长,术后易局部复发,是一种低度恶性的肿瘤。鉴于病变黏液样基质及各类炎细胞浸润的背景较为突出,而特征性的瘤细胞稀疏,应注意与炎症性病变或具有相似组织形态的良性或恶性肿瘤鉴别。 相似文献
75.
慢性肾小球肾炎病人白细胞糖皮质激素受体的变化 总被引:1,自引:0,他引:1
以氚标记的地塞米松(~3H-Dex)为配体,用一点分析法测定了23例慢性肾小球肾炎病人混合白细胞的糖皮质激素受体(GCR),平均为8825±2429位点/细胞((?)±SD)。与正常人5154±1635位点/细胞相比相差十分显著,P<0.01。其中16例并发尿毒症患者的GCR平均为9464±2571位点/细胞((?)±SD)。对这种变化的可能机制和临床意义进行了讨论。 相似文献
76.
Yuxiang Ma Daxian Zhang Teruyuki Kawabata Takahiro Kiriu Shinya Toyokuni Koji Uchida Shigeru Okada 《Pathology international》1997,47(4):203-208
The copper and Iron status in the liver of non-tumor bearing Long-Evans Cinnamon (LEC) rats (average age 17 months) was investigated. A direct quantitation of loosely-bound copper and iron was also investigated by using a chelating agent, nitrilotriacetic acid (NTA-chelatable free copper and iron). Besides the total copper and iron contents, the level of NTA-chelatable free copper was also higher in LEC rats than In LEA rats (P<0.05). But for the free iron level there was no signiflcant difference between the two rat groups (P>0.05). The formation of thiobarbituric acid-reactive substances was higher In LEC rats than In LEA rats (P<0.01). The 4–hydroxy-2–nonenal (HNE)-modified proteins were also clearly demonstrated in LEC rat liver. The copper and iron which produced the most important effect In the process of oxidative damage in LEC rats could not be distinguished. Even though free copper, which could induce free radical injuries, was increased in LEC rats, neither tumor-induction nor preneo-plastic lesions in the experimental LEC rats were observed. Therefore it is speculated that the elevation of a free iron is another important factor. Copper and iron, both important translation metals In the body, may participate In the Induction of DNA damage and oncogenesls 相似文献
77.
Yang YZ Tian JM Tian JT Chen ZQ Deng XJ Zhang DH 《Journal of biomedical materials research》2000,52(2):333-337
Graded porous titanium coatings have been deposited on titanium substrates for dental implants by plasma spraying in an argon atmosphere. X-ray diffraction (XRD), scanning electron microscopy (SEM), surface roughness measurement, and tensile strength tests were performed on graded porous coatings. The results showed that Ti(3)O(5) was formed in the outermost surface of the porous coatings due to oxidation. The graded porous coatings consisted of three layers. The outer layer was full of macropores with a surface roughness of approximately 100 microm. The diameter of many macropores reached and even surpassed 150 microm, which could be beneficial for tissue to grow into the coating. The middle layer consisted of a mixture of micropores and macropores. The inner layer was a very dense and tight interface layer that included mechanical, physical, and metallurgical bonding. In tensile strength tests, testing bars peeled off the coatings, because the adhesive agent fractured, but the coatings remained intact. 相似文献
78.
The intent of the present study was to use chemical or electrical stimulation of cerebellar afferents to determine how different stimulation paradigms affect the pattern of activation of different populations of neurons in the cerebellar cortex. Specifically, we analyzed immediate changes in neuronal activity, identified neurons affected by different stimulation paradigms, and determined the time course over which neuronal activity is altered. In the present study, we used either systemic (harmaline) or electrical stimulation of the inferior cerebellar peduncle (10 and 40 Hz) to alter the firing rate of climbing and mossy fiber afferents to the rat cerebellum and an antibody made against the proto-oncogene, c-fos, as a marker to identify activated neurons and glia. In control animals, only a few scattered granule cells express nuclear Fos-like immunoreactivity. Although no other cells show Fos-like immunoreactivity in their nuclei, Purkinje cells express Fos-like immunoreactivity within their somatic and dendritic cytoplasm in control animals. Within 15 min of chemical or electrical stimulation, numerous granule and glial cells express Fos-like immunoreactivity in their nuclei. Cells in the molecular layer express Fos-like immunoreactivity following harmaline stimulation in a time and lobule specific manner; they do not appear to be activated in the electrical stimulation paradigm. Following harmaline injections, there is an initial loss of Fos-like immunoreactivity in the cytoplasm of Purkinje cells; 90 min later, nuclear staining is observed in a few scattered Purkinje cells. Following electrical stimulation, the cytoplasmic staining in Purkinje cells is enhanced; it is never present in the nucleus. Data derived from this study reveal cell-specific temporal and spatial patterns of c-Fos activation that is unique to each paradigm. Further, it reveals the presence of an activity dependent protein in the cytoplasm of Purkinje cell somata and dendrites. 相似文献
79.
80.
VALUE AND LIMITATIONS OF SINUS NODE FUNCTION TE.ST
BY ATRIAL PACING IN SICK SINUS SYNDROME DIAGNOSIS
Sun Rui-long孙瑞龙 Chen Xin陈新 Wang Fang-zhengHu Sheng-jun胡绳俊 Tian Rui-guo田瑞国and Qi Lian-xiaClinical Electrophysiology Laborato''ry Institute of Cardiovascular Diseases Chinese Academy of Medical Sciences Beijing 《中华医学杂志(英文版)》1984,97(2):142-146
In order to evaluate the significance of the
sinus node function test by transvenous atrial
pacing in the diagno,sis of sick sinus syndrome
(SSS), sinus node recovery time (SRT), co]rrected
sinus node recovery time (CSRT) and total atrio-
sinus and sino-atrial conduction time (SACT)
are observed in 69 patients including non-SSS
group 39 cases and SSS group 30 cases.
According to our data, we suggest criteria
for sinus node dysfunction as follows. SRT>1,400
ms and/or A-V junctional esca.pe before sinus
recovery and;or secondary pause, CSRT>560 ms.
total SACT>300 ms. With l item abnormal, the
false positive rat.e in the non-SSS group is 7.7c7。
and the false negative rate in the S.SS group 3.30i"
with 2 items abnormal, the false positive rate in
the non-SSS group Oi and the false negative
rate in the SSS grOiup 6.7'70.
Atropine test results are compared with that
of atrial pacing, 95.8To and 84.2% are compatible
with each other in these 2 groups. In order to
cut the use of invasive technic to the minimum,
we propose performing the atropine test first.
Only in those with unexplainable test results
should the trial pacing test. be resorted to.. 相似文献