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排序方式: 共有709条查询结果,搜索用时 15 毫秒
1.
肺癌脑转移的CT研究 总被引:1,自引:0,他引:1
目的:研究分析肺癌脑转移瘤的CT特征和规律。材料与方法:回顾总结并分析经病理证实的74例肺癌脑转移病例,就其转移灶的CT特征和规律做出评价。结果:肺癌脑转移以顶、额叶为好发部位,转移灶主要表现为结节状均一强化和环状强化中心低密度,可单发或多发。瘤周水肿以腺癌和低分化癌较明显。环状强化中心低密度灶周水肿较结节均一强化灶周水肿明显。结论:CT增强扫描能清楚地显示转移灶的大小、部位、形态、边缘状况和密度变化,是肺癌脑转移的首选检查方法。 相似文献
2.
内蒙古赤峰地区鼠疫现状和流行趋势预测及控制措施的研究 总被引:36,自引:0,他引:36
赤峰地区于1948 ̄1996年发现了16632.2km^2鼠疫自然疫源地,分布于11个旗(县、区)。目前达到控制鼠疫面积13917.8km^2,占疫源地总面积的83.68%。选取与疫源地相关的12种量经因子进行聚类分析,结果可分为:1.疫源性长存区;2.动物鼠疫间断流行区;3.鼠疫动物病控制区;4.疫源性基本消除区。同时对措施进行了探讨。 相似文献
3.
西辽河平原西北侧低山丘陵黄鼠疫源地的发现与研究 总被引:30,自引:28,他引:2
1985年首次从西辽河平原西北侧低山丘陵草原的达乌尔黄鼠及寄生蚤方形黄鼠蚤松江亚种检出4株鼠疫杆菌,到1989年共检出鼠疫菌57株,判定疫点47个。1985~1991年共检出达乌尔黄鼠鼠疫阳性血清271份,阳性率3.44%,几何平均滴度为1:99.17。疫点和血凝阳性点的空间分布约3000km~2。疫源地的主要宿主为达乌尔黄鼠,主要媒介为方形黄鼠蚤松江亚种。动物鼠疫的流行呈单峰型,流行高峰时点在5月17日,1987年为流行高峰年,坡麓为该鼠疫疫源地的频发生境。 相似文献
4.
We have identified an autoantigen that is recognized by antibodies from an 18-year-old female with a history of recurrent infections who later in her clinical course developed Raynaud's phenomenon and telangiectasias. By indirect immunofluorescence (IIF), the index serum produced a unique cytoplasmic discrete speckled (CDS) staining pattern that partially colocalized with early endosome antigen 1 (EEA1) but not Golgi complex or other cytoplasmic organelles in HEp-2 cells. When HEp-2 cells were treated with 0.1 N HCl, the cytoplasmic speckled staining of the index serum was markedly decreased, suggesting that the reactive antigen was soluble. Western blot analysis showed a reactive approximately 97 kDa protein in a saline soluble protein preparation from HeLa cells. Mass spectrometric analysis of the excised 97 kDa band that was immunoprecipitated from HeLa cell extracts identified GRASP-1 as a possible target. The index serum and anti-GRASP-1 antibodies colocalized to structures in the cytoplasm of HEp-2 cells. Synthetic peptides representing the full-length GRASP-1 protein were used to identify reactive epitopes. Like many other cytoplasmic autoantigens, GRASP-1 has numerous coiled-coil domains throughout the protein with the exception of short segments at the amino and carboxyl terminus. 相似文献
5.
西部开发中的虫媒病传播问题 总被引:1,自引:1,他引:1
陆宝麟 《寄生虫与医学昆虫学报》2003,10(4):212-217
西部开发地区存在许多虫媒病 ,即昆虫和蜱螨传播的疾病 ,为了保障开发人群的健康 ,首先需要对这些疾病的传播 ,特别是有些疾病的自然疫源地或流行区有所了解。本文列述了 13种虫媒病及其在这个地区的分布 ,对其中值得我们更重视的 4类重要疾病 ,包括鼠疫、莱姆病、疟疾和登革热的病原体传播媒介或有的贮存宿主以及重要性等作了扼要的介绍。本文并提出了这类疾病在开发中和开发后可能产生的危害性 ,以及防止或减少它们危害的建议。作者认为从开发地区的长远利益出发 ,应该重视开发中自然环境改变对上述虫媒病传播影响的研究 相似文献
6.
Kazuo Takei Hidenobu Watanabe Takao Itol Toshihiko Saito 《Pathology international》1996,46(11):908-917
Twenty lntramucosal tumors of ‘carclnomaln-adenoma’ and 43 ademas (39 pylorlc gland type, 4 Intestinal type) of the gall-bladder were studied to establish more precise histo-logical criteria of carcinoma or adenoma In cases of ‘carcinoma In pyforic gland type adenoma’, to compare carcinoma In adenoma with pure, that Is, without adenomatous components, carcinoma, and to confirm the benign nature of spin-dle cell fd in the adenomas. Ki-67 and p53 immunostaining and nuclear morphomety were used. Eight pure intramucessl cancers were used as controls. The formalin-fixed, paraffln+mbedded sections were stained with p53 and Ki-67 antibodies. Splndle cell foci were observed only In the adenoma area of the pyloric gland type, wlth a frequency of 23% In 39 adenomas, and of 45% in 20 tumors of carclnoma-lrradenoma. Ki-67 staining was negative in 129 of 130 spin-die cell foci examlned, regardless of their size, and positive in only one focus (550 pm in size, Ki-67 Index 0.2%). All of the spindle cell foci were negative for p53 stain. The Ki-67 positive index was 36.6 ± 5.6% In the 8 pure carcinomas, and 12.5 ± 1.9% in the cancer areas of 16 tumors with carcinoma-in-adenoma, while it was 7.9 ± 1.7% in the adenoma areas of 16 tumors with carcinoma-in-adenoma and 4.9 ± 0.5% in the 32 pure pyloric gland adenomas. The p53-protein over-expression was found in seven of eight pure intramucosal cancers, and in one of 16 cancer components of carclnoma-in-adenoma. However, it was not found in any of 16 adenoma components of carcinoma-in-adenoma, and 35 adenomas. Cells of the cancer tissue of carcinoma-In-adenoma showed a significantly larger nuclear area and a larger nuclear minor axis than those of the pyloric gland type adenomas, as well as other architectural and cytologic abnormalities differing from the features of adenomas. These results suggest that clustered spindle cells do not indmte a malignant transformation of adenoma cells and that carcinomas in carcinoma-in-adenoma are dtfferent from pylorlc gland type adenomas In terms of morphology and proliferative activity. Moreover, the results of the present study indicate that carcinomas In carcinoma-ln-adenoma are lower In malignancy than pure carcinomas, and that their genetic abnormaltty may differ from that of pure carcinomas. 相似文献
7.
Kenichi Wakasa Tomoko Haba Masaomi Sasaki Masami Sakurai Takashl Ikebe Taichi Shuto Kazuhiro Hirohashi Hiroaki Kinoshita 《Pathology international》1998,48(1):29-32
In the cirrhotic and precirrhotic liver, there may be small foci with increased cellularity and amphophilic cytoplasm. These are microscopic lesions that do not form macroscopically detectable nodules, which differ from the macroscopically apparent nodules of dysplastic nodules. In the present study, we assessed the proliferating activity of 12 hyperplastic foci in 11 patients with cirrhosis or chronic hepatitis, by staining for agyrophilic nucleolar organizing regions (AgNOR). The mean AgNOR count per nucleus in the hyperplastic foci ranged from 0.96 to 1.36 (mean, 1.13; SD 0.12), and from 0.81 to 1.06 (mean, 0.94; SD 0.08) in the controls. The AgNOR count In the hyperplastic foci was significantly higher than that In the controls (P> 30.01). Small hyperplastic foci show Increased proliferative activity. Further study on these foci is required to clarify their relation to hepatocarcinogenesis. 相似文献
8.
目的:探讨单光子断层扫描(SPECT)对颅内非局灶性病变致癫痫的无创性定位诊断的作用和临床意义,并与EEG,MRI进行比较,方法:对88例癫痫病人分别在1-2周内行SPECT,EEG,MRI检查,比较3种方法的检出率,准确度,特异度,敏感度,阳性及阴性预测值,结果:SPECT的检出率,准确率,敏感度,阴性预测值显著高于MRI(P<0.05),其特异度显著低于MRI(P<0.05),SPECT的检出率,准确度,特异度,敏感度,阳性及阴性预测值与EEG比较,均无显著性差异(P>0.05),结论:SPECT检查在癫痫定位中优于MRI,其对单一癫痫灶的检出亦优于EEG。 相似文献
9.
B. Denk J. G. Filser E. Deml W. Kessler J. Shen D. Oesterle 《Archives of toxicology》1990,64(4):329-331
Male and female Sprague-Dawley rats, 4–6 days old were exposed for 3 weeks (6 h/day, 5 days/week) to 2-nitropropane vapours of 0, 25, 40, 50, 80 and 125 ppm. One week later polychlorinated biphenyls (Clophen A50, 10 mg/kg body weight) were administered for promotion twice a week for 8 weeks. Thirteen weeks after starting the experiments the logarithms of the numbers of preneoplastic liver foci deficient in adenosine-5-triphosphatase were found to be linearly related to the exposure concentrations of 2-nitropropane. Male rats exhibited an approximately four times lower foci incidence than females. 相似文献
10.
洞庭湖垸外血吸虫病易感地带野粪分布及与感染螺密度相关研究 总被引:4,自引:0,他引:4
目的探讨洞庭湖垸外血吸虫病易感地带距大堤不同距离湖洲野粪分布特点及与感染螺密度的关系。方法1987~1994年,选择洞庭湖区30个村外洲进行了观察。结果,野粪污染湖洲以牛、猪、人为主,离大堤愈近,密度愈高。牛粪在各距离中均占绝大多数,且离堤愈远比例愈高;猪粪集中分布在距大堤300m内;人粪呈散在分布。结论<300m,各年感染螺密度均>0.005只/0.11m2,属一级易感地带,且与野粪密度有直线相关关系;然两者均呈逐年下降之势。300m外,年间虽有变化,但无规律 相似文献