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991.
M Yamamoto Y Kubota M Matsuura J Y Homma 《The Kitasato archives of experimental medicine》1988,61(2-3):127-135
992.
993.
994.
Anti-NGF therapy profoundly reduces bone cancer pain and the accompanying increase in markers of peripheral and central sensitization 总被引:7,自引:0,他引:7
Sevcik MA Ghilardi JR Peters CM Lindsay TH Halvorson KG Jonas BM Kubota K Kuskowski MA Boustany L Shelton DL Mantyh PW 《Pain》2005,115(1-2):128-141
Bone cancer pain can be difficult to control, as it appears to be driven simultaneously by inflammatory, neuropathic and tumorigenic mechanisms. As nerve growth factor (NGF) has been shown to modulate inflammatory and neuropathic pain states, we focused on a novel NGF sequestering antibody and demonstrated that two administrations of this therapy in a mouse model of bone cancer pain produces a profound reduction in both ongoing and movement-evoked bone cancer pain-related behaviors that was greater than that achieved with acute administration of 10 or 30 mg/kg of morphine. This therapy also reduced several neurochemical changes associated with peripheral and central sensitization in the dorsal root ganglion and spinal cord, whereas the therapy did not influence disease progression or markers of sensory or sympathetic innervation in the skin or bone. Mechanistically, the great majority of sensory fibers that innervate the bone are CGRP/TrkA expressing fibers, and if the sensitization and activation of these fibers is blocked by anti-NGF therapy there would not be another population of nociceptors, such as the non-peptidergic IB4/RET-IR nerve fibers, to take their place in signaling nociceptive events. 相似文献
995.
Kentaro Yamane Nobuo Kai Tetsuro Mazaki Tadashi Miyamoto Tomohiro Matsushita 《Journal of orthopaedic science》2018,23(5):739-743
Background
Long-term exposure to radiation can lead to gene mutations and increase the risk of cancer. Low rate fluoroscopy has the potential to reduce the radiation exposure for both the examiner and the patient during various fluoroscopic procedures. The purpose of this study was to evaluate the impact of low rate fluoroscopy on reducing an examiner's radiation dose during nerve root block.Methods
A total of 101 lumbar nerve root block examinations were performed at our institute during a 6-month period. During the first 3 months, low rate fluoroscopy was performed at 7.5 frames/s (FPS) in 54 examinations, while 47 were performed at 15 FPS during the last 3 months. The examiner wore a torso protector, a neck protector, radiation protection gloves, and radiation protection glasses. Optically stimulated luminescence (OSL) dosimeter badges were placed on both the inside and the outside of each protector. The dosimeters were exchanged every month. Radiation doses (mSv) were measured as the integrated radiation quantity every month from the OSL dosimeters. The effective and equivalent doses for the hands, skin, and eyes were investigated.Results
The mean monthly equivalent doses were significantly lower both inside and outside the hand protector for the 7.5 FPS versus 15 FPS (inside; P = 0.021, outside; P = 0.024). There were no significant differences between the two groups for the mean monthly calculated effective dose for each protector's condition.Conclusions
Radiation exposure was significantly reduced for the skin on the examiner's hand when using low rate fluoroscopy at 7.5 FPS, with no noticeable decrease in image quality or prolonged fluoroscopy time. 相似文献996.
K Kubota K Ishiwata S Yamada R Kubota M Tada T Sato T Ido 《The Tohoku journal of experimental medicine》1992,168(2):437-439
A comparative multiple-tracer study was performed to assess the tracer feasibility of monitoring tumor radiotherapy. Metabolic tracers for glucose, amino acid, nucleic acid metabolism: F-18-FDG, C-14-Met, H-3-Thd, and F-18-FdUrd and conventional Ga-67 were compared in the same AH109A radiotherapy model using a new quadruple-tracer technique. F-18-FDG showed a large uptake change and a steady response to radiotherapy which is similar to Ga-67. F-18-FdUrd showed a rapid decrease, but the range of change in uptake was narrow. H-3-Thd and C-14-Met showed a rapid response to irradiation and a high sensitivity for monitoring radiotherapy, suggesting that if labeled with C-11, they may be feasible for PET study. 相似文献
997.
S Yamada R Kubota K Kubota K Ishiwata T Ido 《The Tohoku journal of experimental medicine》1992,167(3):181-184
In 18F micro-autoradiography using a frozen section method, the grain production was measured relative to the exposure time and radioactivity. The grain production increased until 6-hr exposure, but 7-hr or longer exposure induced a characteristic of latent image fading. However, the ratios of the efficiency of grain production between two different 18F-radioactivities (11.9 and 2.3 mBq/100 microns2) were constant over experimental exposure times, thus indicating that quantitative analysis by grain counting is preserved. 相似文献
998.
Isolation of Legionella anisa from multiple sites of a hospital water system: the eradication of Legionella contamination 总被引:1,自引:0,他引:1
999.
Efficacy of CS-834 against Experimental Pneumonia Caused by Penicillin-Susceptible and -Resistant Streptococcus pneumoniae in Mice 下载免费PDF全文
Takashi Fukuoka Harumi Kawada Akiko Kitayama Tetsufumi Koga Mikie Kubota Tamako Harasaki Yasuki Kamai Satoshi Ohya Hiroshi Yasuda Masayuki Iwata Shogo Kuwahara 《Antimicrobial agents and chemotherapy》1998,42(1):23-27
The efficacy of CS-834, a novel oral carbapenem, was assessed by using a murine model of pneumonia caused by penicillin-susceptible and penicillin-resistant Streptococcus pneumoniae and was compared with those of oral cephems, i.e., cefteram pivoxil, cefpodoxime proxetil, cefdinir, and cefditoren pivoxil. Intranasal inoculation of 106 CFU of penicillin-susceptible or penicillin-resistant S. pneumoniae in the exponential growth phase induced pneumonia and bacteremia in ddY mice within 48 h. For the treatment of infections caused by the penicillin-susceptible strain the antibiotics were administered orally at 0.4, 2, and 10 mg/kg of body weight twice daily for 2 days beginning at 24 h after bacterial inoculation, and for the treatment of infections caused by a penicillin-resistant strain the antibiotics were administered at 2, 10, and 50 mg/kg twice daily for 2 days beginning at 24 h after bacterial inoculation. Among the antibiotics tested, CS-834 exhibited the most potent efficacy against both types of strains. Against infections caused by penicillin-susceptible S. pneumoniae, CS-834 at all doses significantly reduced the numbers of viable cells in both the lungs and blood. Cefpodoxime proxetil at all doses and cefteram pivoxil and cefditoren pivoxil at doses of 2 and 10 mg/kg showed comparable efficacies. Against infections caused by penicillin-resistant S. pneumoniae, CS-834 at doses of 10 and 50 mg/kg showed the most potent efficacy among the antibiotics tested, resulting in the maximum decrease in the numbers of viable cells in the lungs. Comparable efficacies were observed with cefteram pivoxil and cefpodoxime proxetil at doses of 50 mg/kg each. The concentration of CS-834 in the lungs and blood was higher than that of cefdinir and was lower than those of the other antibiotics tested, suggesting that the potent therapeutic efficacy of CS-834 reflects its strong activity against S. pneumoniae. 相似文献
1000.
Mechanisms of resistance to imipenem and ampicillin in Enterococcus faecalis 总被引:5,自引:0,他引:5 下载免费PDF全文
We found ampicillin- and imipenem-resistant isolates of vanA-possessing Enterococcus faecalis with MICs of 8 to 16 microg/ml and 4 to 32 microg/ml, respectively. There have been few reports about penicillin- and imipenem-resistant E. faecalis. Two mechanisms of beta-lactam resistance in E. faecalis, the production of beta-lactamase and the overproduction of penicillin-binding proteins (PBPs), have been reported. The resistant isolates in the current study did not produce any beta-lactamases and analysis of the PBPs showed no overproduction. However, the affinities of PBP4 for beta-lactams in the resistant strains were lower than those of susceptible strains but the affinities of other PBPs for beta-lactams did not change. Accordingly, whole pbp4 fragments from these resistant isolates were sequenced. Two amino acid substitutions at positions 520 and 605 were observed in the highly resistant strains compared to the susceptible ones, Pro520Ser and Tyr605His, and a single Tyr605His amino acid substitution was found in the low-resistance strains. These two point mutations exist in the region between the active-site-defining motifs SDN and KTG of the penicillin-binding domain, the main target of beta-lactams. A strong correlation was seen between these substitutions and decreasing affinities of PBP4 to beta-lactams. In E. faecalis, resistance due to mutations in PBPs has not been reported, though it has in Enterococcus faecium. Our results suggest that development of high-level resistance to penicillins and imipenem depends on point mutations of PBP4 at positions 520 and 605. 相似文献