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61.
Hidemi Kaname Toshio Yoshihara Yuji Yaku Tetsuo Ishii 《Medical Electron Microscopy》1993,26(2):99-104
Primary squamous cell carcinoma of the submandibular gland is a rare tumor. In this report, the histological and ultrastructural
features of a case of primary squamous cell carcinoma arising in the left submandibular gland is presented. Light microscopically,
the tumor consisted of well differentiated keratinizing squamous cell nests. Ultrastructurally, the tumor cells were oval
or spindle-shaped, and several tumor cells had intracytoplasmic desmosome-like structures, resembling intercellular desmosomes.
The majority of the tumor cells contained a large number of intermediate filaments (tonofilaments). Intercellular desmosomes
were well developed. No secretory granules were found. These ultrastructural features may enable us to distinguish primary
squamous cell carcinoma from mucoepidermoid carcinoma which is often misdiagnosed as squamous cell carcinoma. 相似文献
62.
The effect of halothane and enflurane on tracheal tone were studied in 21 patients during the induction of anesthesia. Endotracheal tube cuff pressure was used to measure tracheal tone. Anesthesia, maintained by nitrous oxide 70% in oxygen, was supplimented with succinylcholine drip infusion to immobilize the patient. Ventilation was controlled by a Volume-preset ventilator. In the halothane group, the initial cuff pressure was 14.8 ± 1.3 (mean ± SE) cmH2O but 10min after 0.15mg/kg of pancuronium injection, it increased to 21.7 ± 2.3cmH2O (control). Ten min after inhalation of 0.75% of halothane, cuff pressure decreased to 14.7 ± 2.3cmH2O (34 ± 11% decrease from the control value). In the enflurane group, the initial cuff pressure was 17.6 ± 1.8cmH2O and it increased to 21.0 ± 1.7cmH2O (control) 10min after pancuronium injection. Ten min after 1.7% of enflurane inhalation, cuff pressure decreased to 17.1 ± 2.3cmH2O (23.9 ± 6% decrease from the control value). Halothane and enflurane produced similar tracheal dilatation in healthy individuals.(Yasuda I, Irimada M, Hirano T et al.: Tracheal dilatation by halothane and enflurane in man. J Anesth 2: 46–49, 1988) 相似文献
63.
Summary A monoclonal antibody, termed AD11/8, reactive to microglial cells, was produced by immunization of mice with partially purified amyloid fibrils of senile (neuritic) plaques. With immunoperoxidase staining on human tissues, AD11/8 also recognized macrophages in the red pulp of the spleen, Kupffer cells in the liver, and macrophages in the bone marrow. The results show that AD11/8 recognizes the antigens associated with mononuclear phagocytes lineage. In normal brains a few resting microglial cells were stained in gray matter, and less frequently in white matter. In senile dementia of the Alzheimer type numerous microglial cells were stained intensively and they often formed clusters in gray matter. By double immunostaining with AD11/8 and a polyclonal antibody against synthetic amyloid -protein, clustered microglial cells were observed in and around senile plaques with amyloid deposits. Some amyloid plaque cores were surrounded by microglial cell processes. These results indicate that microglial cells may play an important role in senile plaque formation.Supported in part by the Grant-in Aid for Scientific Research from the Ministry of Education, Science and Culture, the grants for Research of Dementia and for Primary Amyloidosis from the Ministry of Health and Welfare, Japan 相似文献
64.
Y. Hirata K. Fukui Y. Dan H. Matsuoka T. Sugimoto M. Ishii 《European journal of clinical pharmacology》1989,36(6):575-578
Summary The renal and hormonal effects of the 1-adrenoceptor blocker bunazosin were examined in 6 patients with essential hypertension. Oral bunazosin for 4 to 12 weeks significantly decreased mean blood pressure by 10%, increased effective renal blood flow and creatinine clearance by 34% and 37%, respectively, the plasma norepinephrine concentration was elevated by 60%, and the plasma atrial natriuretic peptide level was lowered by 22%. The plasma renin activity and aldosterone concentration were unchanged. Thus, a moderate reduction in blood pressure was produced by bunazosin treatment while maintaining renal perfusion. 相似文献
65.
H Imura T Takahashi T Matsuda O Yoshida H Ohkura Y Seitetsu Y Seino M Ishii M Kuwabara Y Ariyoshi 《Gan to kagaku ryoho. Cancer & chemotherapy》1989,16(6):2195-2202
We describe an immunoradiometric competitive inhibition assay of the serum levels of the 2----6 sialyl Lewisa antigen, using "SLA 2-6 Otsuka" kits. The assay required only duplicate 50-microliters samples, and the concentration of 2----6 sialyl Lewisa antigen in serum was determined by reference to a standard curve ranging from 0 to 160 arbitrary U/ml. The intra- and inter-assays reproducibilities were good and analytical recovery of antigen were excellent. The serum levels of the antigen were highly dependent on the Lewis blood types of the tested individuals; i.e., the levels of the antigen in the sera of the Lewisa-b- individuals were significantly lower than those of the antigen obtained with the Lewisa+b- and Lewisa-b+ individuals. The cut-off value (42 U/ml) was obtained as mean + 2SD, which was carefully calculated from the antigen levels in sera of the non-Lewisa-b- individuals. 相似文献
66.
Tsukasa Tsunoda Toshifumi Eto Takahito Tsurifune Shigeki Tokunaga Tatsuhiro Ishii Koichi Motojima Teiji Matsumoto Tohru Segawa Kazuhide Ura Hiroshi Fukui 《Pathology international》1991,41(10):763-770
A solid and cystic tumor (SCT) was located at the head of the pancreas in a 43-year-old Japanese male, and pancreatoduodenectomy was performed on the suspicion of papillary carcinoma or cystadenocarcinoma of the pancreas. The lesion, which measured 4.5 X 4.5 X 4.0 cm, was clearly demarcated by connective tissue. The cut surface showed solid grayish-white areas with central cystic degenerative changes. The solid areas consisted of small round cells proliferating in a small solid or a pseudopapillary pattern. The tumor cells partially invaded the surrounding normal pancreatic parenchyma. Immunohistochemical studies revealed positive staining for alpha-1-antitrypsin and neuron-specific enolase, but no staining for known pancreatic hormones. Moreover, ultrastructural studies showed the absence of zymogen granules and the presence of anullate lamellae and neurosecretory granules. On the basis of these findings, a diagnosis of SCT of the pancreas was established. In order to clarify the histogenesis and biological behavior of the tumor, it is necessary to accumulate and analyze similar cases, an endeavor which in turn will contribute to the successful management of this disease. Acta Pathol Jpn 41: 763-770, 1991. 相似文献
67.
Mycobacterium bovis BCG cell wall-specific differentially expressed genes identified by differential display and cDNA subtraction in human macrophages
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68.
Kiyoshi A Ishikawa T Hayashi K Iwatsuki Y Ishii K Nakayama K 《Pflügers Archiv : European journal of physiology》2003,447(2):142-149
Rhythmical contractions accompanied by an increase in cytosolic Ca2+ concentrations were produced in ring preparations of endothelium-denuded pulmonary arteries from monocrotaline-treated rats, but not in those from vehicle-treated rats, 2-3 h after a resting tension of 15 mN (150-180% of the initial wall length of the artery) was applied. The rhythmical contractions were abolished by nicardipine and ryanodine. Cyclopiazonic acid reduced the relaxation phase of the rhythmical contractions, finally leading to a sustained contraction. Similarly, apamin caused a sustained contraction, whereas charybdotoxin increased the amplitude of the rhythmical contractions. Glibenclamide had no apparent effects on them. Indomethacin and the prostaglandin H2/thromboxane A2 receptor antagonist SQ29548 abolished the rhythmical contractions and reduced the tension, but the thromboxane synthase inhibitor ozagrel had no effect. These results suggest that optimal stretch induces rhythmical contractions in the pulmonary arteries of monocrotaline-induced pulmonary hypertensive rats, to which both Ca2+ influx through voltage-operated Ca2+ channels and Ca2+ release from the endoplasmic reticulum seem to contribute. It is also suggested that small-conductance Ca(2+)-activated K+ channels participate in the relaxation phase of rhythmical contractions. Furthermore, prostaglandin H2 released from nonendothelial cells is likely to play a pivotal role in the induction of rhythmical contractions. 相似文献
69.
Evaluation of anti-parvovirus B19 activity in sera by assay using quantitative polymerase chain reaction 总被引:4,自引:0,他引:4
Saito T Munakata Y Fu Y Fujii H Kodera T Miyagawa E Ishii K Sasaki T 《Journal of virological methods》2003,107(1):81-87
Human parvovirus B19 (B19) infects cells of erythroid lineage. Production of neutralizing antibodies (Abs) is indispensable for recovery from B19-related disease state. In this study, we used a convenient method to measure neutralizing activities in human sera by using a real-time quantitative PCR based assay. Erythroid cell line KU812Ep6 was incubated with test sera before infection with B19 virus. The copy number of B19-DNA in cultures was decreased in the presence of the sera from patients who recovered from acute B19 infection, whereas no decrease in B19-DNA was in cultures incubated with sera from healthy volunteers who had no B19 infection. The decrease in B19-DNA copy number was calculated and the inhibition percentage was expressed as neutralizing activity to B19. A clinical study showed that the levels of neutralizing ability were high in patients who recovered soon after acute B19 infection, but were low in some patients with a prolonged clinical course for recovery from B19 infection. This method is simple and convenient compared with methods described previously, showing its usefulness to evaluate the neutralizing activity to B19. 相似文献
70.
Hibasami H Moteki H Ishikawa K Katsuzaki H Imai K Yoshioka K Ishii Y Komiya T 《International journal of molecular medicine》2003,11(1):23-26
Protodioscin (PD) was purified from fenugreek (Trigonella foenumgraecum L.) and identified by Mass, and 1H- and 13C-NMR. The effects of PD on cell viability in human leukemia HL-60 and human stomach cancer KATO III cells were investigated. PD displayed strong growth inhibitory effect against HL-60 cells, but weak growth inhibitory effect on KATO III cells. Morphological change showing apoptotic bodies was observed in the HL-60 cells treated with PD, but not in KATO III cells treated with PD. Flow cytometric analysis showed that the hypodiploid nuclei of HL-60 cells were increased to 75.2, 96.3, and 100% after a 3-day treatment with 2.5, 5, and 10 microM PD, respectively. The fragmentation by PD of DNA to oligonucleosomal-sized fragments, that is a characteristic of apoptosis, was observed to be both concentration- and time-dependent in the HL-60 cells. These findings suggest that growth inhibition by PD of HL-60 cells results from the induction of apoptosis by this compound in HL-60 cells. 相似文献