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排序方式: 共有4717条查询结果,搜索用时 15 毫秒
1.
Abidur Rahman Makoto Kobayashi Kotaro Sugimoto Yuta Endo Manabu Kojima Shigenori Furukawa Takafumi Watanabe Shu Soeda Yuko Hashimoto Keiya Fujimori Hideki Chiba 《International journal of molecular sciences》2021,22(7)
Background: Within the claudin (CLDN) family, CLDN12 mRNA expression is altered in various types of cancer, but its clinicopathological relevance has yet to be established due to the absence of specific antibodies (Abs) with broad applications. Methods: We generated a monoclonal Ab (mAb) against human/mouse CLDN12 and verified its specificity. By performing immunohistochemical staining and semiquantification, we evaluated the relationship between CLDN12 expression and clinicopathological parameters in tissues from 138 cases of cervical cancer. Results: Western blot and immunohistochemical analyses revealed that the established mAb selectively recognized the CLDN12 protein. Twenty six of the 138 cases (18.8%) showed low CLDN12 expression, and the disease-specific survival (DSS) and recurrence-free survival rates were significantly decreased compared with those in the high CLDN12 expression group. We also demonstrated, via univariable and multivariable analyses, that the low CLDN12 expression represents a significant prognostic factor for the DSS of cervical cancer patients (HR 3.412, p = 0.002 and HR 2.615, p = 0.029, respectively). Conclusions: It can be concluded that a reduced CLDN12 expression predicts a poor outcome for cervical cancer. The novel anti-CLDN12 mAb could be a valuable tool to evaluate the biological relevance of the CLDN12 expression in diverse cancer types and other diseases. 相似文献
2.
Sachiyuki Hasegawa Kazuyuki Shimizu Takeshi Kobayashi Masakazu Matsubara 《Journal of chemical technology and biotechnology (Oxford, Oxfordshire : 1986)》1985,35(1):33-42
Repeated batch operation using two fermentors (RBTF) to penicillin fermentation was demonstrated by computer simulation to improve productivity. Three operation modes were compared: chemostat, repeated batch operation using a single fermentor (RBSF) and RBTF; in each case account was made of the lag period before growth. The simulated fermentor performances were assessed on the basis of the penicillin productivity and concentration; the simulation was based on published batch fermentation data. It was shown that RBTF was superior to RBSF and chemostat. The advantage of RBTF increased as the lag period became greater. 相似文献
3.
E Kobayashi Y Yoshida A Fujimura T Yamanaka H Endo T Hamamoto Y Kagawa 《Canadian Metallurgical Quarterly》1997,24(12):1775-1777
We studied the in vivo gene transfusion using a gene gun, formerly used in plants and culture cells. The hand-held type gene gun (Helios Gene Gun System) is simple and convenient for effective gene transfection in living animals. This method has some advantages in that there is no need for use of viral vector, independence on the cell cycle and local inducement of plural genes. There is a great possibility for application to local-regional cancer. 相似文献
4.
BACKGROUND/PURPOSE: Recent reports have identified abnormal innervation of the circular muscle layer involving the fine intramuscular nerve fibers in hypertrophic pyloric stenous (HPS). HPS presenting after 3 months of age is rare. The aim of this study was to determine the distribution pattern of nerve fibers in the smooth muscle layers in HPS and correlate this with age at presentation. METHODS: Full-thickness pyloric muscle biopsy specimens were obtained from eight patients with HPS (five age 3 to 5 weeks, two age 3 months, and one age 7 months) and five controls with normal pylorus (age 5 days to 3 years). All specimens were stained with monoclonal antibody to the neural cell adhesion molecule (NCAM) using immunohistochemistry. RESULTS: There were many NCAM-positive nerve fibers in the circular and longitudinal muscle layers in the controls. No NCAM positive nerve fibers were seen in the circular or longitudinal muscle layers in the five cases of HPS in which the patients were less than 5 weeks old. In the two cases in which the patients were 3 months old, occasional NCAM-positive nerve fibers were seen in the circular layer, and moderate numbers of NCAM positive fibers were seen in the longitudinal muscle layers. Moderate numbers of NCAM-positive nerve fibers in the circular muscle layer and many NCAM positive nerve fibers in the longitudinal muscle layers were identified in the 7-month-old HPS patient. CONCLUSIONS: The data suggest that the pyloric muscle lacks innervation in the young HPS infant. Whereas, at 3 months of age the hypertrophied pyloric muscle is partially innervated, and at 7 months of age the pyloric muscle has practically normal innervation. 相似文献
5.
Kobayashi K. Kameyama M. Higuchi T. 《Industrial Electronics, IEEE Transactions on》1997,44(3):418-426
A new token-passing mechanism, priority token passing, which features real-time access and fast detection and recovery of transmission errors, is discussed in detail in comparison with standard token-passing protocols, and its large-scale integration (LSI)-oriented design concept is described. Priority token passing includes only a small performance overhead, due to its switching functions, which can change network topology from ring to broadcast medium. A token-holding node passes the token to another node after determining the successor through priority comparison. Errors occurring during token passing can, thus, be detected and corrected simply and promptly. Priority token passing has a simple hardware implementation, requiring only small additions to the frame control circuitry, and has a small implementation overhead. The priority token-passing protocol and two other important network communication functions, dual ring network reconfiguration and high-level data link control (HDLC) normal response mode-based message transmission, are designed as a single finite-state machine, and implemented into a compact LSI chip. This integrated instrument network (IINET) chip provides complete network communication services and requires only three additional external electronic components for operation 相似文献
6.
J Chehimi NM Valiante A D'Andrea M Rengaraju Z Rosado M Kobayashi B Perussia SF Wolf SE Starr G Trinchieri 《Canadian Metallurgical Quarterly》1993,23(8):1826-1830
Natural killer cell stimulatory factor (NKSF) or interleukin-12 (IL-12) is a heterodimeric cytokine with pleiomorphic effects on T and NK cells, including induction of lymphokine production, mitogenesis, and enhancement of spontaneous cytotoxic activity. Similarly to IL-2, NKSF/IL-12 enhances NK cell-mediated cytotoxicity within a few hours and independently from induced proliferation. This effect is independent from other induced cytokines, because it is not prevented by antibodies neutralizing interferon (IFN)-alpha, IFN-beta, IFN-gamma, IL-2 or tumor necrosis factor (TNF)-alpha and, unlike the induction of IFN-gamma production by peripheral blood lymphocytes, it does not require HLA class II-positive accessory cells. Enhanced cytotoxicity is accompanied by morphologic changes in NK cells, including a significant increase in the number of cytoplasmic granules. In addition to the previously described ability to enhance the cytotoxic activity of NK cells against tumor-derived target cells, NKSF/IL-12 is also a potent stimulator of cytotoxicity against virus-infected cells, either fibroblasts acutely infected with herpes viruses or T cell lines chronically infected with human immunodeficiency virus-1. NK cell-mediated antibody-dependent cytotoxicity or anti-CD16 antibody-redirected lysis is not significantly enhanced by NKSF/IL-12. However, the ability of resting peripheral blood T cells to mediate anti-CD3 antibody-redirected lysis is enhanced by 18-h incubation with NKSF/IL-12, indicating that this lymphokine can modulate the cytotoxic capability of both NK and T cells. 相似文献
7.
H Ota T Katsuyama S Nakajima H El-Zimaity JG Kim DY Graham RM Genta 《Canadian Metallurgical Quarterly》1998,29(8):846-850
Helicobacter pylori seem to avoid areas of intestinal metaplasia in the gastric mucosa, but attachment of these bacteria to epithelium with the appearance of incomplete intestinal metaplasia has been documented. To characterize the nature of the epithelium to which H pylori was attached, we carried out an immunohistochemical study using monoclonal antibodies against gastric surface mucous cell mucins (M1), blood group-related carbohydrates antigens (Le(a), sialyl Le(a), Le(b), type 1H, and type 2H) and sialyl Tn antigen. The results of this study suggest that these areas of H pylori attachment represent a hybrid epithelium whose cells share characteristics of both gastric surface mucous cells and intestinal metaplastic cells. Whether all areas of incomplete intestinal metaplasia represent an intermediate stage between the normal gastric epithelium and the fully developed complete type of metaplasia remains to be determined. 相似文献
8.
P. Perugini M. Vettor R. Tursilli† S. Scalia† I. Genta T. Modena F. Pavanetto B. Conti 《International journal of cosmetic science》2006,28(2):148-149
Due to the reduction of the ozone layer, there is an increasing need of effective UV protection systems with minimized side-effects. Trans-2-ethylhexyl- p -methoxycinnamate ( trans -EHMC) represents one of the most widely used sunscreen compound. Several studies demonstrated that trans -EHMC is unstable following UV irradiation both in solution and in emulsion formulations. Moreover, various reports of photocontact sensitization induced by trans -EHMC have appeared in the literature. Consequently, in order to ensure adequate efficacy and safety for this sunscreen agent, there is a need for new carrier systems to enhance trans -EHMC photostability. In the present study the photostability of the filter in different formulation types (emulsion–gel, gel and emulsion) with various ingredients is evaluated. In addition, nanoparticles based on poly- D , L -lactide-co-glycolide (PLGA) as carrier for trans -EHMC are investigated. The influence of nanoparticle matrix on the photochemical stability of the sunscreen agent is also presented. The results obtained demonstrated that PLGA nanoparticles are effective in reducing the light-induced degradation of the sunscreen agent. Moreover, the choice of formulation type and the excipients used play an important role in order to obtain a stable cosmetic product containing trans -EHMC. 相似文献
9.
N. Karasawa H. Kakehata K. Mishina J. Yamamoto S. Kobayashi 《Photonics Technology Letters, IEEE》2005,17(1):31-33
Using a cross-correlation frequency-resolved optical gating apparatus, the phases and amplitudes of ultrabroad-band optical pulses from a taper fiber have been measured for various input pulse peak powers. The measured waveforms have been compared with calculated waveforms using a finite-difference in the frequency domain method, in which no envelope approximations were used and the variation of the taper shape was taken into account. Excellent agreement between the measured and the calculated waveforms was obtained when the additional dispersion of a normal fiber and an objective was considered. 相似文献
10.
Hitoshi Kurokawa Taku Nakayama Yasunori Kobayashi Ken Suzuki Mutsumi Takahashi Seiichi Takami Momoji Kubo Naotsugu Itoh Parasuraman Selvam Akira Miyamoto 《Catalysis Today》2003,82(1-4):233-240
A modified Monte Carlo (MC) simulation was performed to investigate the hydrogen absorption behavior in Pd and Pd–Ag alloys of the composition PdxAg1−x (x=0.7–0.8) under H2 pressure (0.1 MPa) at different temperatures. The present method employed can consider the dissociative adsorption of hydrogen molecule and the subsequent absorption of hydrogen atom by formalizing the relationship between the pressure of hydrogen molecule and hydrogen atom. The potential parameters were determined to reproduce the solution enthalpy of hydrogen in pure metals. The results are in good agreement with experimental findings as well as previous theoretical studies. We confirmed that our method is useful to simulate the absorption of hydrogen in metals and alloys. 相似文献