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81.
Koichi Yasuda Hideki Minatogawa Yasuhiro Dekura Seishin Takao Masaya Tamura Nayuta Tsushima Takayoshi Suzuki Satoshi Kano Takatsugu Mizumachi Takashi Mori Kentaro Nishioka Motoyasu Shido Norio Katoh Hiroshi Taguchi Noriyuki Fujima Rikiya Onimaru Isao Yokota Keiji Kobashi Shinichi Shimizu Akihiro Homma Hiroki Shirato Hidefumi Aoyama 《Journal of radiation research》2021,62(2):329
Pharyngeal cancer patients treated with intensity-modulated proton therapy (IMPT) using a model-based approach were retrospectively reviewed, and acute toxicities were analyzed. From June 2016 to March 2019, 15 pharyngeal (7 naso-, 5 oro- and 3 hypo-pharyngeal) cancer patients received IMPT with robust optimization. Simulation plans for IMPT and intensity-modulated X-ray therapy (IMXT) were generated before treatment. We also reviewed 127 pharyngeal cancer patients with IMXT in the same treatment period. In the simulation planning comparison, all of the normal-tissue complication probability values for dysphagia, dysgeusia, tube-feeding dependence and xerostomia were lower for IMPT than for IMXT in the 15 patients. After completing IMPT, 13 patients completed the evaluation, and 12 of these patients had a complete response. The proportions of patients who experienced grade 2 or worse acute toxicities in the IMPT and IMXT cohorts were 21.4 and 56.5% for dysphagia (P < 0.05), 46.7 and 76.3% for dysgeusia (P < 0.05), 73.3 and 62.8% for xerostomia (P = 0.43), 73.3 and 90.6% for mucositis (P = 0.08) and 66.7 and 76.4% for dermatitis (P = 0.42), respectively. Multivariate analysis revealed that IMPT was independently associated with a lower rate of grade 2 or worse dysphagia and dysgeusia. After propensity score matching, 12 pairs of IMPT and IMXT patients were selected. Dysphagia was also statistically lower in IMPT than in IMXT (P < 0.05). IMPT using a model-based approach may have clinical benefits for acute dysphagia. 相似文献
82.
Assay method for Vibrio cholerae and Escherichia coli enterotoxins by automated counting of floating chinese hamster ovary cells in culture medium. 下载免费PDF全文
As Chinese hamster ovary (CHO) cells on plastic proliferate, many cells float off into the medium instead of piling up after they form a monolayer. Fewer cells were floating in the medium when CHO cells were incubated with cholera toxin at a concentration as low as 10 pg/ml. The toxin increased the adhesiveness of the cells forming confluent monolayers so that the floating cells accumulated on the adherent monolayers. On the basis of this finding, a simple, quantitative assay method for cholera and Escherichia coli enterotoxins was devised by cultivating CHO cells in a Linbro multidish and counting the cells in the medium with a Coulter Counter. The method was sensitive enough to detect toxins in 100- to 200-fold-diluted culture media of toxigenic E. coli strains. Little or no activity was detected by this method in the culture medium of nontoxigenic E. coli. 相似文献
83.
Fundal atrophic gastritis and Helicobacter pylori have been implicated as possible etiologic factors in gastric cancer. This case-control study was performed to determine which risk factor is more closely related to gastric cancer. The endoscopic Congo red test was performed to evaluate the extent of fundal atrophic gastritis in 43 patients with gastric cancer and 86 cancer-free control subjects, who were individually matched by age, sex, and date of endoscopy (within 3 months). The prevalance of H. pylori infection and severe fundal gastritis were significantly higher in patients with differentiated adenocarcinoma, but not with undifferentiated adenocarcinoma, than in control subjects. The odds ratios for differentiated and undifferentiated adenocarcinomas were 6.85 (95% confidence interval, 1.94-11.82) and 1.50 (95% CI, 0.84-3.11), respectively. However, the odds ratio of H. pylori infection was greater than that of severe fundal gastritis. Moreover, multivariate analysis provided similar results. H. pylori infection is an independent indicator of a higher risk of the differentiated adenocarcinomas of the stomach than is severe fundal gastritis. 相似文献
84.
Growth suppression of non-small cell lung carcinoma cells by the introduction of the p16(INK4A) gene
The p16(INK4A) gene is frequently inactivated in nonsmall cell lung carcinoma (NSCLC) by either mutations, deletions or DNA methylations. To assess the biological significance of p16(INK4A) inactivation in the development of NSCLC, full-length p16(INK4A) cDNA was introduced into NSCLC cell lines, A549 and H322, in which p16(INK4A) was homozygously deleted. NSCLC cells transfected with the p16(INK4A) expression vector formed colonies in 20-68% of those with a control vector, and exogenous p16(INK4A) protein was expressed in 4 of 68 A549-derived clones and none of 29 H322-derived clones, respectively. A549-derived clones which stably expressed the exogenous p16(INK4A) gene showed significant decrease in growth rate in vitro and tumorigenicity in vivo in proportion to the level of p16(INK4A) expression. Furthermore, the cell cycle of these cells significantly delayed with accumulation of cells in G1 phase. Micro-injection of p16(INK4A) expression vector also revealed that p16(INK4A) blocked S phase entry in both A549 and H322 cells. These results suggest that the restoration of the p16(INK4A) function suppresses the growth of NSCLC cells by induction of G1 arrest in the cells. Therefore, inactivation of p16(INK4A) may play an important role in the enhancement of unregulated NSCLC growth in vivo. 相似文献
85.
Summary The incidence of high cervical disc lesions is extremely rare, and the mechanism of their development is unclear. We report
these three cases, and discuss the possible mechanisms. We also describe surgical strategies for these lesions.
The first and second cases were an 82-year-old male and an 84-year-old male with retro-odontoid disc hernia. The third was
an 83-year-old female with a herniated disc at C2/C3. To investigate Aetiological mechanisms of these lesions, we examined
the findings on cervical images in extension and flexion, and compared the results in a younger than 80-year-old group and
an older than 80-year-old group.
The patients underwent surgery via a posterolateral intradural approach. Wide laminectomy and incision of the dentate ligaments
enabled access to the ventral space of the upper cervical spinal canal and sufficient decompression. All patients became ambulatory
postoperatively without special fixation of the cervical spine. In the younger group, the level mostly loaded during cervical
movement was C5/6, however, the levels in the older group were C2/3 and C3/4.
In elderly patients, less mobilization of the middle and/or lower cervical spine due to spondylotic change causes overloading
at higher levels resulting in high cervical disc lesions. Retro-odontoid disc lesions can be caused by a herniated disc at
C2/C3, which migrates upward. Regarding surgical strategy, the posterolateral intradural approach is less invasive and more
advantageous for these lesions. 相似文献
86.
Endovascular treatment of ruptured dissecting aneurysms aimed at occlusion of the dissected site by using Guglielmi detachable coils 总被引:13,自引:0,他引:13
Yamaura I Tani E Yokota M Nakano A Fukami M Kaba K Matsumoto T 《Journal of neurosurgery》1999,90(5):853-856
OBJECT: Surgical or endovascular occlusion of the parent artery proximal to an aneurysm has been recommended for treatment of dissecting aneurysms of the intracranial posterior circulation. However, dissecting aneurysms may rupture even after proximal occlusion because distal progression of thrombus is necessary to occlude the dissecting aneurysm completely, and this may be delayed by the presence of retrograde flow. In this article the authors present their experience in treating six patients with ruptured dissecting aneurysms. METHODS: The authors report on six patients with a ruptured dissecting aneurysm in the posterior fossa who were successfully treated by endovascular occlusion of the aneurysm by using Guglielmi detachable coils. The procedure was particularly aimed at occluding the dissected site. CONCLUSIONS: At the present time, endovascular occlusion of the dissected site is a safe, minimally invasive, and reliable treatment for dissecting aneurysms when a test occlusion is tolerated and adequate collateral circulation is present. 相似文献
87.
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90.
Aneurysm of persistent primitive hypoglossal artery 总被引:2,自引:0,他引:2
A patient with a ruptured intracranial aneurysm of the right persistent primitive hypoglossal artery is described. Clipping of the aneurysmal neck was achieved by a far lateral approach together with drilling of the jugular tubercle, and it was concluded that this approach should be followed for safe and complete clipping. 相似文献