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排序方式: 共有1185条查询结果,搜索用时 15 毫秒
1.
Rena Fushiki Kotoe Mayahara Mai Ogawa Yasuyo Takahashi Yoko Karasawa Niina Tsurumachi 《Connective tissue research》2015,56(4):336-341
Purpose: Orthodontic tooth movement occurs during the bone remodeling induced by therapeutic mechanical strain. It is important to investigate the relation between the strength of mechanical stress and bone formation activity. The aim of this study was to determine the effect of high-magnitude mechanical strain on bone formation in detail.Materials and methods: Osteoblast-like cells isolated from fetal rat calvariae were loaded with 18% cyclic tension force (TF) for 48?h. To phenotypically investigate the effect of TF, we measured the number and the size of bone nodules stained by von Kossa technique on day 21 after cell seeding and determined the calcium content of bone nodules on day 14. Furthermore, we examined the gene expression of BMP-2, Runx2 and Msx2, which are important factors for bone nodule formation, on days 1, 4 and 7 after TF loading.Results: The maximum bone nodule size in the control group was 1620 and 719?μm in the TF group. Furthermore, the mean number of bone nodules sized over 360?μm in the TF group was significantly decreased compared to the control group. The calcium content was also significantly decreased to 42% by TF loading. The mRNA expression of BMP-2, Runx2 and Msx2 was decreased 1 and 4 days after TF loading.Conclusion: The differentiation of bone forming progenitor cells into bone nodule forming cells was inhibited by TF due to the decreased expression of bone formation related factors such as BMP-2, Runx2 and Msx2. 相似文献
2.
Yasuyo Shintani Yoshihisa Sawada Takeshi Inagaki Yasuo Kohjimoto Yasunari Uekado Toshiaki Shinka 《International journal of urology》2007,14(2):140-146
AIM: In order to clarify the initial step of the mechanism by which bacillus Calmette-Guérin (BCG) exhibits antitumor activity via the immune response induced in the bladder submucosa after intravesical BCG therapy for human bladder cancer, various cytokines secreted in the urine after BCG instillation were measured. METHODS: After transurethral resection of bladder cancer, a 6-week course of BCG instillation was performed. At the first and sixth weeks' dosings, spontaneously excreted urine was collected before and 4, 8, and 24 h after BCG instillation. The urinary cytokines were determined by Sandwich enzyme-linked immunosorbent assay using monoclonal antibodies against granulocyte-macrophage colony-stimulating factor (GM-CSF), tumor necrosis factor (TNF)-alpha, granulocyte colony-stimulating factor (G-CSF), interleukin (IL)-1beta, IL-8, interferon (IFN)-gamma, and IL-12. RESULTS: After the BCG therapy, various cytokines, such as GM-CSF, TNF-alpha, G-CSF, IL-1beta, IL-8, IFN-gamma, and IL-12 were secreted, comprising the immune response cascade. The mean urinary excretions of GM-CSF and TNF-alpha 4 h after the sixth week's instillation were significantly higher than the pre-instillation levels. There were no significant increases in the urinary IFN-gamma or IL-12 levels between 4 and 24 h after the sixth week's instillation. The TNF-alpha level 4 h after the sixth week's instillation had a strong tendency towards the absence of recurrence, with a mean follow-up of 54.1 months. The Kaplan-Meier curve showed the 2, 5, and 10-year recurrence-free survival rates were 72.4%, 65.8%, and 56.4%, respectively. CONCLUSIONS: We suggested that the urinary levels of TNF-alpha might be essential in antitumor activity after BCG therapy and might play an important role in the prevention of bladder tumor recurrence. 相似文献
3.
Previous studies have suggested that inhaled furosemide may have a protective effect against a wide variety of bronchoconstrictor agents, but a therapeutic effect has not been established in acute exacerbation of asthma. The purpose of this study was to investigate whether inhaled furosemide would exhibit any therapeutic benefit in acute asthma. We conducted a double-blind, placebo-controlled, randomized study in 40 patients with acute mild or moderate exacerbation of asthma. All patients received intravenous (IV) aminophylline 250 mg for 90 min and IV hydrocortisone 100 mg at entry. After randomization, 3 patients were excluded from the final analysis. At 30 min after starting IV aminophylline, 20 patients were given inhaled furosemide 20 mg and 17 patients received normal saline as placebo-control. Both inhalations were given by a jet nebulizer. The baseline forced expiratory volume at 1 sec (FEV1), peak expiratory flow rate (PEFR), and serum concentration of theophylline did not differ between the two groups. An increase in FEV1 in the furosemide group by 28.2 ± 5.9% (mean ± SE) was noted at 60 min, and this was significantly higher than in the control group. PEFR at 60 min was also significantly higher in the furosemide group than in control group. We conclude that inhaled furosemide has a bronchodilator effect on mild to moderate exacerbation of asthma when it is used with IV theophylline. Inhaled furosemide may benefit certain acute asthma patients, especially those suffering complications from the adverse effects of β2-agonists. 相似文献
4.
1. Whether bradykinin (BK), which is known as an endogenous pain-producing substance, induces augmentation of the discharges of polymodal receptors evoked by heat stimulation was investigated in in vitro canine testis-superior spermatic nerve preparations. 2. The heat response was significantly augmented by pretreatments with BK at concentrations greater than 0.094 nM, whereas BK induced significant increases in the mean discharge rates at concentrations above 9.4 nM. Both effects increased in a concentration-dependent manner. The augmenting effect of BK on the heat response diminished within 10 min after application of BK, regardless of concentration. 3. When 9.4 nM BK was applied in a mixture with 940 nM NPC349, a B2 receptor antagonist, the averaged mean discharge rate evoked by BK and the averaged augmenting effect were both significantly suppressed compared with those induced by BK given alone. 4. The augmenting effect of BK on the heat response of polymodal receptors could be observed even in the absence of BK-evoked discharges per se in several cases in which low concentrations of BK or BK plus B2 antagonists were given. 5. These findings suggest that the augmenting effects of BK on the heat response depend on B2 receptor-mediated intracellular processes acting in parallel to, but not directly on, the impulse-generation mechanism of the heat response of the polymodal receptor. 相似文献
5.
When stimulating the mixed nerve to record evoked potential, both sensory and motor fibers are activated before entering the spinal cord. The N10 potential has been described as an antidromic motor evoked potential based on results obtained by recording at the anterior midneck. In the present study, we examined the changes in latencies of Erb's potential, N10, and N13 by stimulating the median nerve distally at the wrist and proximally at the elbow. The conduction velocity of N10 calculated by the difference between N10 latencies at the two stimulation points was consistent with motor conduction velocity, although N13 conduction velocity estimated by the same method reflected a sensory conduction velocity. A positive relation was also observed between the indirect latency from the stimulation point to the anterior root as calculated using the equation (F - M - 1) / 2 (ms) and the direct latency to the negative peak of the N10 potential. Our data support the notion that N10 represents antidromic motor potential originating in the spinal entry zone of the anterior root. 相似文献
6.
Kentaro Yamashita Hiroyuki Tsukuda Yasuyo Mizukami Jun Ito Shigeo Ikuta Yoshihiro Kondo Hiroshi Kinoshita Yasunori Fujisawa Kohzoh Imai 《Journal of gastroenterology》1997,32(5):684-688
A case of hepatic infarction with portal thrombosis is reported. A 63-year-old woman with liver cirrhosis and esophageal varices
was admitted for treatment of the esophagel varices. Endoscopic variceal ligation (EVL) and endoscopic injection sclerotherapy
(EIS) were performed. Two months later, she experienced right hypochondralgia and right flank pain. Serum transaminase levels
were suddenly elevated, and computed tomography scans of the liver showed multiple small nodular lesions. Her condition worsened,
and she died of hepatic failure. Autopsy revealed splenic and portal vein thrombosis, multiple hepatic infarction, and evidence
of chronic pancreatitis. We believe that liver cirrhosis and chronic pancreatitis were the main risk factors for the portal
thrombosis, and the treatment for esophageal varices appeared to have triggered the thrombosis. The hepatic infarction was
caused by the portal thrombosis. 相似文献
7.
Toshiya Inada M.D. Fumiko Minagawa B.A. Satoru Iwashita M.D. Tatsuji Tokui M.D. 《Psychiatry and clinical neurosciences》1994,48(4):729-735
Abstract: In order to examine the characteristics of potential difficult-to-manage psychiatric cases, seven potential subgroups were extracted from the criminal offenders who were sent to the division of psychiatric diagnosis, Tokyo District Public Prosecutors Office for Pre-Prosecution Psychiatric Justice (PPPJ). The following criteria were used to select the potential subgroups: offenders who had experienced compulsory discharge from a mental hospital, those who had experienced Involuntary Admission to the mental hospital by the Prefectural Governor at least twice, those who had experienced admission to mental hospitals on more than 5 occasions, those who had been put on PPPJ previously for other criminal matters at least 3 times, those who had previously attempted suicide, and those who had committed homicide or arson. From the results of this study, it could be concluded that at least two types of "difficult-to-manage" psychiatric cases exist in the criminal offenders. 相似文献
8.
Yamamoto K Okamura A Minagawa K Yakushijin K Urahama N Gomyo H Shimoyama M Itoh M Matsui T 《Cancer Genetics and Cytogenetics》2003,147(2):128-133
Follicular lymphoma is characterized genetically by t(14;18)(q32;q21), whereas t(18;22)(q21;q11), a rare variant form of t(14;18), has been preferentially observed in chronic lymphocytic leukemia (CLL). We describe here an unusual case of follicular lymphoma with a t(18;22)(q21;q11), that progressed to diffuse large cell lymphoma with a novel t(2;6)(p12;q23). Spectral karyotyping revealed that add(2)(p12) and add(6)(q23) were derived from a t(2;6)(p12;q23). Fluorescence in situ hybridization analysis confirmed rearrangements of the BCL2 gene at 18q21 and the BCL6 gene at 3q27. Our results indicate that a reciprocal translocation involving 6q23 could be implicated in the progression of follicular lymphoma and that t(18;22) may have a specific role in the pathogenesis of follicular lymphoma as well as CLL. 相似文献
9.
Nakamura M Yamanaka G Kawashima H Watanabe Y Ioi H Kashiwagi Y Takekuma K Hoshika A Hayakawa M Suzuki S 《Disease markers》2005,21(4):199-202
The characteristics of influenza-associated encephalopathy is the high mortality and nimble progress with coma which appears in general cases within 48 hours. Most of patients show no abnormalities in the standard blood checks on admission or in early stage. In this study we investigated if a rapid assay of interleukin (IL)-6 is useful in influenza-associated encephalopathy in early stages. The levels of IL-6 in patients with influenza-associated encephalopathy did not show any significant difference compared with those in patients with febrile convulsion and rotavirus-associated convulsion. However the levels of IL-6 in severe cases were significantly higher than those of mild cases with influenza-associated encephalopathy. Consequently the rapid assay of serum IL-6 is useful to evaluate and decide the therapies. 相似文献
10.
Fukai Y Amino H Hirawake H Yabu Y Ohta N Minagawa N Sakajo S Yoshimoto A Nagai K Takamiya S Kojima S Kita K 《Comparative biochemistry and physiology. Part C, Pharmacology, toxicology & endocrinology》1999,124(2):141-148
Trypanosome alternative oxidase (TAO) is the terminal oxidase of the respiratory chain of long slender bloodstream forms (LS forms) of African trypanosoma, which causes sleeping sickness in human and nagana in cattle. TAO is a cytochrome-independent, cyanide-insensitive quinol oxidase and these properties are quite different from those of the bacterial quinol oxidase which belongs to the heme-copper terminal oxidase superfamily. Only little information concerning the molecular structure and enzymatic features of TAO have been available, whereas the bacterial enzyme has been well characterized. In this study, a cDNA encoding TAO from Trypanosoma brucei brucei was cloned into the expression vector pET15b (pTAO) and recombinant TAO was expressed in Escherichia coli. The growth of the transformant carrying pTAO was cyanide-resistant. A peptide with a molecular mass of 37 kDa was found in the cytoplasmic membrane of E. coli, and was recognized by antibodies against plant-type alternative oxidases from Sauromatum guttatum and Hansenula anomala. Both the ubiquinol oxidase and succinate oxidase activities found in the membrane of the transformant were insensitive to cyanide, while those of the control strain, which contained vector alone, were inhibited. This cyanide-insensitive growth of the E. coli carrying pTAO was inhibited by the addition of ascofuranone, a potent and specific inhibitor of TAO ubiquinol oxidase. The ubiquinol oxidase activity of the membrane from the transformant was sensitive to ascofuranone. These results clearly show the functional expression of TAO in E. coli and indicate that ubiquinol-8 in the E. coli membrane is able to serve as an electron donor to the recombinant enzyme and confer cyanide-resistant and ascofuranone-sensitive growth to E. coli. This system will facilitate the biochemical characterization of the novel terminal oxidase, TAO, and the understanding on the mechanism of the trypanocidal effect of ascofuranone. 相似文献