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81.
82.
S Matsukuma Y Ozeki K Takagi K Kikuchi S Tanaka T Ogata 《[Zasshi] [Journal]. Nihon Kyōbu Geka Gakkai》1990,38(7):1188-1191
A neurofibroma originated from the intrathoracic vagal nerve was presented. A 26-year-old male was found to have an abnormal shadow in the right chest filed on a routine examination. He was complicated with Von Recklinghausen's disease and showed multiple "cafe au lait" spots over his extremities and trunk but no subcutaneous mass. A block resection of the mass was carried for the mediastinal tumor. The tumor was arising from the right intrathoracic vagal nerve which located just below the origin of recurrent nerve and was measured 3 X 3 X 6 cm. Histological examination of the specimen revealed neurofibroma. His postoperative course was uneventful. A brief review in Japan was made on 22 cases collected from the literature. 相似文献
83.
84.
Machine oils are widely used in metal processing and many workers are exposed to oil mists in the work environment. Some investigators have pointed out such health hazards due to prolonged exposure to oil mist as respiratory disorders, dermatitis, and possible carcinogenesis. In Japan, a permissible limit of oil mists of 3 mg/m3 was recommended in 1977 by the Japan Association of Industrial Health (JAIH) mainly based on the hazardous effects on the respiratory system. After this recommendation was made, only a few studies have been made on the measurement of oil mists and on the health effects in machine workers to determine whether the permissible limit is justifiable or not. In the present study, the levels of oil mists in the air of machine workshops were measured together with personal exposure levels by personal samplers. Oil mists were collected by a sampler head with 2 stages which enabled differentiation of distribution of particulates between larger than 10 microns and 2-10 microns in size. Oil components collected on the stainless steel stages were washed out by sonication in CCl4 solution and measured by an oil meter with infra-red spectrometry against a standard solution of heavy oil class B according to procedures reported elsewhere by the authors. Questionnaire surveys were also conducted on 308 male machine workers composed of 221 workers exposed to oil mists and 87 nonexposed controls. The questions were composed of five items about air quality in the work environment and 18 subjective symptoms during work and daily lives. The symptoms included nasopharyngeal, muco-dermal, gastrointestinal and neuro-muscular symptoms. Statistical analysis was made by the Manthel-Haenszel method for a comparison of "yes" rates of complaints between the exposed and the non-exposed by adjusting the underlying confounding factor of age distribution. 1. The levels of oil mists measured here ranged from 94 to 813 micrograms/m3 in the ambient air and from 107 to 483 micrograms/m3 of personal exposure. There was no obvious difference between the level in the ambient air and that of personal exposure. All these measured levels were under the permissible limit (3 mg/m3) recommended by JAIH in 1977. 2. The observed distribution of particulate size of oil mists from 2 to 10 microns referred to as respirable size was 32.8 +/- 16.1% generated from the grinding machines using water-soluble type of machine oils and 50.0 +/- 12.4% from those using insoluble type.(ABSTRACT TRUNCATED AT 400 WORDS) 相似文献
85.
通过检测E6变体在HPV16阳性的宫颈非典型增生(CIN)和宫颈浸润癌(ICC)患者中的分布,研究其致癌能力.方法:用PCR和双脱氧终止荧光法检测了42例E6基因点突变及其编码氨基酸改变,统计分布差异.结果:2例(5%)为原型,40例(95% )的E6DNA序列中含有1至3个点突变,导致13类E6氨基酸残基改变,组合成17种(94%)HPV16变体.出现频率较高的4种变体在CIN和ICC病例中共同存在,分布无显著性差异(P>0.05).DNA的点突变数在CIN和ICC病例中的分布也无显著性差异(P>0.05).结论:HPV16E6的变体多于原型,但是变体和原型的致癌能力没有明显差别. 相似文献
86.
Eiji Satoh Hirofumi Naganuma Atsushi Sasaki Mitsuyasu Nagasaka Hitoshi Ogata Hideaki Nukui 《Journal of neuro-oncology》1997,33(3):195-200
Glioblastoma cells secrete transforming growth factor- (TGF-), whichhas a variety of immunosuppressive properties. We investigatedthe effect of irradiation TGF- secretion by malignantglioma cells. Three malignant glioma cell lines (T98G,A172, KG-1-C) were cultured and irradiated using 10and 50 Gy Linac radiation. After further culturefor 36 hours in serum-free culture medium, thesupernatants were collected. The TGF- activity in theculture supernatants was determined using a specific bioassay.The levels of the active form and totalTGF- in the supernatants from irradiated malignant gliomacells decreased compared to those from un-irradiated cells.However, since irradiation inhibited the growth of tumorcells, the amount of TGF- secretion per cellin irradiated cells tended to increase after irradiation.These results suggest that malignant glioma cells canstill secrete TGF- and activate latent TGF- evenafter large dose irradiation, despite the inhibition oftumor growth. 相似文献
87.
Shunsuke Kageyama Hiroshi Yamamoto Mitsuyo Nagano Harumi Arisaka Takashi Kayahara Ryota Yoshimoto 《British journal of pharmacology》1997,122(1):165-171
- A murine anti-human vWF monoclonal antibody, AJvW-2, was developed that inhibited the interaction between platelet glycoprotein Ib (GPIb) and von Willebrand factor (vWF) during the ristocetin- (IC50=0.7±0.1 μg ml−1) and botrocetin- (IC50=1.8±0.3 μg ml−1) induced aggregation of human platelets.
- AJvW-2 inhibited the high shear stress (10.8 N m−2) induced aggregation of human platelets dose-dependently with an IC50=2.4±0.3 μg ml−1, but had no effect on low shear stress induced platelet aggregation (1.2 N m−2) up to 100 μg ml−1.
- AJvW-2 also inhibited the high shear stress (5.0 N m−2) induced adhesion of human platelets to collagen I with the same efficacy (IC50=2.4±0.3 μg ml−1), but had no effect at low shear conditions (1.5 N m−2).
- AJvW-2 inhibited the botrocetin-induced aggregation of platelets from guinea-pig, rat, rabbit, dog and pig at the same concentration range as human platelets; it likewise also inhibited the high shear stress induced aggregation and adhesion to collagen I of guinea-pig platelets.
- AJvW-2 prevented arterial thrombus formation in guinea-pigs at a dose of 100 μg kg−1 without prolonging the template bleeding time, whereas the GPIIb/IIIa antagonist lamifiban mediated inhibition of thrombosis at 1000 μg kg−1 was accompanied by a significant prolongation of the bleeding time.
- These results suggest that AJvW-2 is a potent inhibitor of the GPIb-vWF interaction and a potential novel antithrombotic agent with lower bleeding risk than GPIIb/IIIa antagonists.
88.
Nishio M Xu L Sasaki M Haga S Okumoto M Mori N Sarkar NH Acha-Orbea H Enami J Imai S 《Breast cancer (Tokyo, Japan)》1994,1(2):89-94
Mammary tumors of a newly isolated strain of Chinese wild mouse (JYG mouse) harbor exogenous mouse mammary tumor virus (MMTV). The complete nucleotide sequence of exogenous JYG-MMTV was determined on the proviral 5' long terminal repeat (LTR)(partial)-gag-pol-env-3' LTR (partial) fragment cloned into a plasmid vector and the cDNA sequence from JYG-MMTV producing cells. Similarly to the other MMTV species the LTR of JYG-MMTV contains an open reading frame (ORF). The amino acid sequence of the JYG-MMTV ORF resembles that of SW-MMTV (92% identity) and endogenous Mtv-7 (93% identity) especially at the C-terminal region. Thus, a functional similarity in T-cell receptor V beta recognition as a superantigen is implicated among these MMTV species. Analysis of the viral gag nucleotide sequence revealed that this gene is not disrupted by the bacterial insertion sequence IS1 or IS2, which have been reported to be present in the majority of the plasmids containing the gag region. Comparison of amino acid sequences of JYG-MMTV with those of BR6-MMTV showed that over 96% of the amino acids of gag, pol, protease and env products are identical. These results suggest the intact nature of the nucleotide sequence of the near full-length MMTV genome cloned in the plasmid. 相似文献
89.
Human promyelocytic HL-60 cells can be induced by biochemical agents to differentiate in vitro towards divergent types of myelomonocytic cells. It has been reported that prostaglandin E1 (PGE1) can induce granulocytic differentiation and that 1,25-dihydroxyvitamin D3 (1,25(OH)2D3) can induce monocytic differentiation. We have now examined the effects of these compounds, both alone and in combination, on HL-60 cell differentiation. PGE1 (1 g/ml) or 1,25(OH)2D3 (10 nM) each inhibited cell proliferation over 48–96 hours of treatment, but combined treatment with both agents was necessary to produce a strong inhibition. The percentage of HL-60 cells that can reduce nitroblue tetrazolium (NBT) (a characteristic index of early monocytic or granulocytic differentiation) increased 13-fold within 72 hours of PGE1 treatment, and 1,25(OH)2D3 produced a fivefold stimulation. However, combined treatment (PGE1 plus 1,25(OH)2D3) produced a dramatic 35-fold increase. HL-60 cells did not produce significant levels of nitric oxide (NO) before 48 hours in culture, and treatment with PGE1 or 1,25(OH)2D3 did not significantly increase cellular NO elaboration over control levels. However, combined treatment produced a striking 12-fold increase over control levels. Similarly, combined treatment was necessary to obtain the maximal time-dependent stimulation of cellular lactate dehydrogenase (LDH) activity (a marker of granulocytic differentiation) as well as acid phosphatase (ACP) activity. During this same period of time, PGE1, but not 1,25(OH)2D3, markedly stimulated cellular claboration of interleukin (IL)-1, IL-6, and tumor necrosis factor (TNF)-, and 1,25(OH)2D3 cotreatment strongly augmented these effects. Thus, combined treatment with 1,25(OH)2D3 plus PGE1 generally augmented the apparent conversion of these cells, producing synergistic (multiplicative) or additive effects. Furthermore, PGE1 induced within 48 hours the more general phenotypic changes classically associated with the differentiation of these cells: increased expression of chloroacetate esterase (ChAE) (a granulocytic marker), decreases in the nuclear/cytoplasmic ratio (characteristic of development beyond the promyelocyte/myelocyte stage), and major alterations in morphology from floating spherical cells to loosely adherent, elliptical polygons. 1,25(OH)2D3 had little effect itself on most of these parameters, but augmented the morphological changes induced by PGE1 treatment. Within 48 hours, the ability of these cells to reduce the tetrazolium salt WST-1, a general measure of cellular metabolic activity, was increased by PGE1, but not by 1,25(OH)2D3; however, the combination of 1,25(OH)2D3 and PGE1 again produced the strongest stimulation. Similarly, only PGE1 significantly reduced intracellular ATP levels, but combined treatments produced a more pronounced decrease. In summary, our findings suggest that PGE1, not 1,25(OH)2D3, is sufficient to promote rapid in vitro differentiation of HL-60 cells along the granulocytic pathway; however, the PGE1-induced conversion of these cells is markedly augmented by cotreatment with 1,25(OH)2D3. In addition, these converted HL-60 cells preferentially utilize the glycolytic pathway, rather than the citric acid cycle, for production of ATP, a metabolic characteristic that resembles that described for mature granulocytes. 相似文献
90.
Suzuki T Ogata A Tashiro K Nagashima K Tamura M Yasui K Nishihira J 《Brain research. Brain research protocols》1999,4(3):271-279
We report here an effective and concise method to determine the localization of macrophage migration inhibitory factor (MIF), a proinflammatory cytokine, and its mRNA in the central nervous system of pre- and postnatal rats. This method allows for double staining to demonstrate localization of different molecules on the same tissue specimen at the levels of mRNA and proteins by in situ hybridization and immunohistochemistry, respectively. Additionally, the present method gives results more quickly than the conventional isotopic techniques. By use of this method, we carried out immunohistochemistry with an anti-rat MIF polyclonal antibody and demonstrated positive staining using the avidin-biotin complex method (ABC method). To detect its mRNA, we performed nonradioactive in situ hybridization using a digoxigenin (DIG)-labeled RNA probe prepared from a full length fragment of rat MIF cDNA. MIF was strongly expressed in the telencephalon on embryonic day 16. Non-radioactive in situ hybridization with a DIG-labeled RNA probe as well as the immunohistochemistry described here could be applicable to characterize localization of mRNA and proteins of different molecules on the same tissue specimen. 相似文献