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排序方式: 共有1213条查询结果,搜索用时 31 毫秒
1.
T. Onishi T. Machida N. Iizuka K. Nakauchi H. Shirakawa F. Masuda S. Mochizuki H. Tsukamoto N. Harada 《Urological research》1990,18(5):313-318
Summary Utilizing two types of human renal carcinoma heterotransplanted in nude mice, we investigated the variations in hyperthermic effects (42.5°C for 30 min) caused by differences in tumor type with special reference to variations in tumor vascularity. In the hypovascular JRC1 strain, sporadic vascular dilation was observed throughout the tumors after heating. Destruction of tumor cells was observed mainly in the region of dilation. In the hypervascular JRC11 strain, homogenous vascular dilation was observed immediately after heating, mainly at the periphery of tumors. There was a decrease in the viability of cells in the center of the tumor. Therefore, the hypervascular tumors showed greater destruction mainly at the center where blood circulation was reduced. The range of necrosis was also greatly affected by the extent of vascular dilation caused by heating in hypovascular tumors. 相似文献
2.
原发性腹膜后脂肪肉瘤20例报告 总被引:1,自引:0,他引:1
自1965年5月至1991年7月共收治原发性腹膜后脂肪肉瘤20例,均经手术及病理证实。20例中完全切除者15例,部分切除者4例,活检1例。肿瘤切除合并肾,肠襻等邻近器官切除者达12例。全组的5年,10年生存率分别是57.1%和20.0%,完全切除组的5年10年生存率分别是63.6%和28.6%。20例病人共进行了48次切除手术。首次手术死亡2例。着重讨论了本病的诊断、治疗和突出的临床特点。 相似文献
3.
1株诱变枯草杆菌溶栓酶性质研究的初探 总被引:1,自引:0,他引:1
目的 对从1株诱变的枯草杆菌的发酵液中,通过分离纯化得到的一种活性较高的纤溶酶进行性质研究。方法 按胰酶活性测定法测其水解酪蛋白活性,用SDS-PAGE测定分子量,等电聚焦测定其等电点。采用硫酸酚法测定糖含量,并对其药理性质进行研究。结果 其水解酪蛋白活性为2.1U/mg,分子量为62kDa。等电点为8.5。含糖量为32%,并且发现该酶具有直接降解纤维蛋白的活性。结论 此纤溶酶具有较高的活性及药理价值。 相似文献
4.
Mitsuru Izumisawa DDS Masanori Shozushima DDS PhD Hirotaka Sato DDS PhD 《Oral Radiology》2003,19(2):47-55
Objectives It is known that, in fluorine-18 fluorodeoxyglucose Positron Emission Tomography (FDG PET) for the diagnosis of oral cancer,
FDG uptake may vary even among different cases of the same squamous cell carcinoma. However, the details of this phenomenon
have not yet been elucidated. In this study, we analyzed the relationship between histopathological findings in oral squamous
cell cancer and PET findings on FDG uptake.
Methods We examined 45 patients with oral squamous cell carcinoma who had undergone FDG PET before treatment. FDG uptake was assessed
by a standardized uptake value (SUV) calculated according to the PET-measured tissue concentration of FDG, the administered
dose of radionuclide, and the body weight of the patient. The relationship between the mean SUV and each of the following
parameters was examined: histological grade of malignancy, degree of cell differentiation, size and/or local extent of the
primary lesion, and cell density of the tumor.
Results The mean SUV of FDG uptake did not depend on the histological grade of malignancy or on the degree of cell differentiation,
but tended to be greater the larger the primary lesion. SUV also depended on cell density, increasing with the percentage
of tumor parenchyma.
Conclusions It is concluded that cancer cell density greatly influences the SUV of FDG, in that a tumor with fewer cellular elements in
cancer tissue tends to become a false negative. 相似文献
5.
R. D’Anchise N. Manta E. Prospero C. Bevilacqua A. Gigante 《Journal of orthopaedics and traumatology》2005,6(1):36-43
Abstract
From our overall experience in 56 patients, we here report the treatment with matrix-induced autologous chondrocyte implantation (MACI) of 35 patients suffering from knee cartilage defects measuring about 4 cm2, and followed for a minimum of 6 months. A total of 36 knees were treated (1 patient on both knees) and clinically observed for 22 months (in some cases for over 39 months), in accordance with a standardised protocol. Subjective parameters (pain, well-being, functional state, symptoms during specific activity) and objective outcomes (IKDC score and Lysholm and Tegner scores) were recorded. One or 2 years after implantation, some biopsies of the regenerated cartilage were histologically evaluated. The subjective parameters (VAS pain score, 2.80±1.49, p<0.0001; change vs. basal score, 2.72) promptly normalized after 1 month, as did the objective ones (IKDC score after 6 months, 1.53±0.59, p<0.0001; change vs. basal score, 1.78). Similar results were observed after the treatment of a femoropatellar kissing lesion. The three cartilage biopsies that were analysed from different patients showed a tissue positivity to immunohistochemical markers of hyaline cartilage. The conclusions of this preliminary analysis are that the clinical outcome and histological evaluation suggest that MACI is able to relieve pain and restore the functionality of the knee, and that the treatment appears capable of regenerating hyaline cartilage. 相似文献
6.
测定家蚕幼虫抗氟中毒的抵抗能力,4龄>3龄>2龄。强抗原种杂变组成的杂种一代,抗性介于两亲之间,弱抗原种杂交组成的杂种一代,其抗性表现出超亲的遗传现象,不同浓度的氟素对品种间的生长发育影响有着显著的差异,说明了品种间的抗氟能力存在着差别;抗氟性与DNV抗性有着显著的相关性;与茧质性状表现为不显著的正相关,抗氟性与蚕血中Ca~(2+)、Mg~(2+)含量无明显的相关关系。 相似文献
7.
Claus Zimmer Stefanie Märzheuser Stephan Patt Arndt Rolfs Joachim Gottschalk Klaus Weigel George Gosztonyi 《Journal of neurology》1992,239(7):394-400
Summary In the hope of finding a treatable condition, the need for rapid diagnosis in HIV-seropositive patients with brain lesions is apparent. In order to evaluate the efficacy of stereotactic brain biopsy in AIDS patients, we retrospectively studied 25 HIV-infected patients undergoing stereotactic biopsy. Brain lesions were identified with gadolinium-enhanced MRI and/or contrastCT. Brain biopsy was performed using the system of Riechert. From 8 up to 15 small tissue samples from one or two targets were obtained in every patient. The biopsy material was examined cytologically, histologically (including electron microscopy), immunohistochemically and, in part, by animal test and polymerase chain reaction (PCR). A definite diagnosis was achieved in 92%. Diagnosis included primary central nervous system lymphoma (PCNSL) (10), toxoplasmosis (10), progressive multifocal leukoencephalopathy (2) and one case of co-existing toxoplasmosis and cytomegalovirus infection. Two biopsies were non-diagnostic. All PCNSLs showed polymorphic B-cell populations of high malignancy; accurate classification according to the Kiel classification was not possible. In 3 lymphomas Epstein-Barr nuclear antigen (EBNA) 2-mRNA could be detected by PCR and confirmed immunohistochemically by EBNA 2 expression. In 6 cases autopsy confirmed the biopsy diagnosis. Conventional histology was not sufficiently decisive for toxoplasmosis and progressive multifocal leukoencephalopathy, so that immunohistochemistry and animal tests became very important for a final diagnosis. With the help of different morphological and molecular biological techniques stereotactic brain biopsy appears to be an effective method in the diagnosis of HIV-associated brain lesions. In view of the marked radio- and chemosensitivity of PCNSLs it is mandatory to establish an early and accurate histological diagnosis for adequate treatment. 相似文献
8.
中国三囊库蠓亚属的种类分布及分类研究(双翅目:蠓科) 总被引:2,自引:1,他引:1
本文报告了我国三囊库蠓亚属Culicoides(Trithecoides)已知24种。亚属的鉴别特征,主要特征测量值以及雌虫和雄虫分种检索表。 相似文献
9.
Dr. Ichiro Shimoyama Yoshio Nakajima Toshihiko Ito Tadahiko Shibata 《Brain topography》1997,9(4):271-274
Summary We recorded visual evoked potentials (VEPs) elicited with high or low imaginable Chinese characters (HIC or LIC), representing concrete objects or absolute concepts, respectively. A closed circle (CC) acts as control stimulus. These were displayed (at 1.6° visual angle) for 35 ms on a TV monitor. Twenty-one channel VEPs (band-pas filter: 0.05–60 Hz), using balanced non-cephalic electrodes, were recorded from –100 to 924 ms for 11 right-handed male volunteers. The VEPs were analyzed by multivariate analysis of variance (MANOVA) and comparison of topographies at four remarkable peaks (P110, N160, P230 and N320). MANOVA showed significant differences (p< 0.001) for both conditions of channel and stimuli (HIC, LIC or CC). P100 for the CC-VEPs, N160 for the HIC-and LIC-VEPs, P230 for the CC-VEPs, and N320 for the HIC-VEPs were remarkable in the posterior scalp regions. Topographies at P100 and N160 showed no difference between the HIC-and LIC-stimuli. However, those at N320 showed difference between the HIC-and LIC-stimuli over the occipital and posterior temporal areas. Those results suggest that the responses at P100 and N160 might segregate Chinese characters from non Chinese characters. N320 suggested certain processes in imagery on recognizing Chinese characters over the occipital and posterior temporal areas.We are grateful to Dr. Yoshiji Kojima of Hamamatsu University for helpful comments. 相似文献
10.
Ryuichi Yatani Taizo Shiraishi Kaneyoshi Akazaki Takuji Hayashi Lance K. Heilbrun Grant N. Stemmermann 《Virchows Archiv : an international journal of pathology》1986,409(4):395-405
Summary The histological grades of prostatic carcinoma, as defined by Gleason, were correlated with three methods of morphometry in 254 step-sectioned prostates obtained at autopsy. The variables studied were 1) the number of tumours in each prostate; 2) bilaterality and 3) tumour volume. Each characteristic yielded a statistically significant correlation with histological grade. The strongest correlations were obtained using tumour volume. These autopsy studied help to explain the inconsistent results obtained from morphometric analyses of surgical material, and lend support to the Gleason system as a means of predicting tumour behavior.Supported in part by research contracts PH 64-10, NCI-72-3213, N01-CP-53521; Grant R01-CA-33644; and the Grant-in-Aid for Cancer Research (33) from the Ministry of Health and Welfare 相似文献