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971.
Takafumi Nishizaki Noboru Ohshita Yoshio Nagatsugu Tetsuji Orita Haruhide Ito Kohsuke Sasaki 《Journal of neuro-oncology》1993,17(1):9-13
We evaluated the DNA index values in 28 brain-tumor patients showing DNA aneuploidy on the DNA histogram obtained by flow cytometry. In 17 cases among them, the DNA index values were compared to BUdR labeling indices (BUdR-LI). Average DNA indices of individual tumor types were 1.89 +- 0.10 (6 glioblastomas multiforme), 1.93 +- 0.05 (4 anaplastic astrocytomas), 1.68 +- 0.09 (3 malignant meningiomas), 1.24 +- 0.03 (7 meningiomas), 1.19 +- 0.05 (2 pituitary adenomas) and 1.86 +- 0.24 (6 metastatic brain tumors). Slow-growing tumors such as meningioma and pituitary adenoma, had lower values than malignant tumors, except a case of a metastatic brain tumor. All malignant meningiomas had higher DNA index values than the other meningiomas. No difference was observed between the DNA index values of glioblastomas multiforme and anaplastic astrocytomas. DNA index values were correlated with BUdR-LI values (p < 0.05), and seven cases with low DNA index values (1.13–1.31) had low BUdR-LI values of less than 1%. Others with high DNA index values of 1.44 or more had high BUdR-LI values of 3.5% or more. These results suggest that high DNA index values is related to tumor malignancy, and despite the presence of some disparities, many slow-growing brain tumor has low DNA index values. 相似文献
972.
Yiyu Zou Isamu Horikoshi Tokuzou Kasagi Xueqiu Gu Roman Perez-Soler 《Cancer chemotherapy and pharmacology》1993,31(4):313-318
Summary The plasma levels, organ distribution, and in vivo antitumor activity of free and liposomal doxorubicin injected into the hepatic artery of rats bearing W256 liver tumors were studied. The administration of liposomal doxorubicin resulted in liver-tumor and liver-parenchyma doxorubicin areas under the curve (AUCs) that were 4.7-and 3.8-fold, respectively, those obtained after the administration of free doxorubicin. Spleen and plasma AUCs were also increased by 2.8 and 2.5 times, respectively, following administration of the liposomal form. In contrast, liposomal doxorubicin did not affect heart AUCs; peak doxorubicin levels in heart tissue were three times lower in animals treated with liposomal doxorubicin. Following treatment with the liposomal form, the cumulative urinary excretion of doxorubicin at 8 h was 38 times lower. In good correlation with these findings, liposomal doxorubicin (2.35 mg/kg on day 7) was more effective than free doxorubicin against liver W256 tumors as measured by tumor-growth inhibition at 5 days after treatment (16% for liposomal doxorubicin versus –53.7% for free doxorubicin,P<0.05) and increased life span (ILS; 108% for liposomal doxorubicin versus 27% for free doxorubicin,P<0.05). These results demonstrate that as compared with free doxorubicin, the administration of liposomal doxorubicin into the hepatic artery results in higher drug levels in the liver tumor and enhanced antitumor activity while maintaining the cardioprotective effect of the liposome carrier as suggested by the decreased peak drug levels measured in the heart tissue. 相似文献
973.
This paper describes a three-step procedure for induction of reversible cell synchrony in the G2 phase of the cell cycle of Chinese hamster ovary (line CHO) cells and non-transformed, human skin fibroblast (HSF) cells. The CHO cells are presynchronized in early S phase by isoleucine deficiency and hydroxyurea blockades. The culture is transferred to medium supplemented with the DNA topoisomerase II inhibitor, Hoechst 33342 for 12 hours after which 95% of the cells are arrested in G2 phase. When G2 synchronized cells are transferred to Hoechst-free, complete medium, they divide as a highly synchronous cohort within 3 hours. The HSF cells are initially cultured in low serum to arrest them in G0 and then transferred to complete medium containing aphidicolin to arrest them in early S phase. The culture is then transferred to aphidicolin-free, complete medium with Hoechst 33342 (0.1 g/ml) for 10 hours after which up to 85% of the cells arrest in G2 phase. Synchronous cell division occurs 3.5 hours after transfer of cells to complete, drug-free medium. The synchrony techniques are useful for studying G2/M biochemical events in mammalian cells.Abbreviations -MEM
minimum essential medium alpha medium
- BCS
bovine calf serum
- DMSO
dimethyl sulfoxide
- EDTA
ethylenediaminetetraacetic acid
- FCM
flow cytometry
- PBS
phosphate buffered saline
- Top II
DNA topoisomerase II 相似文献
974.
Natsuko Nozaki-Taguchi Shiroh Isono Takashi Nishino Takeshi Numai Noboru Taguchi 《Journal canadien d'anesthésie》1995,42(8):685-690
We examined the depressant effect of midazolam on respiration in 21 healthy women undergoing lower abdominal surgery with spinal anaesthesia. Airway gas flow, airway pressure, and the sound of snoring were recorded together with arterial oxygen saturation (SpO2. After spinal anaesthesia was established, subjects were deeply sedated with pentazocine 15 mg followed by incremental doses of midazolam 1 mg iv up to 0.1 mg · kg?1. When SpO2 decreased to < 90% or snoring and/or apnoea was observed, continuous positive airway pressure applied through the nose (nasal CPAP) was increased until the respiratory deterioration was reversed. While one patient remained free of respiratory events, the other 20 patients were successfully treated with nasal CPAP restoring normal SpO2 (95.5 ± 1.7%) without snoring. Stepwise reduction of nasal CPAP determined the minimally effective CPAP to prevent snoring to be 5.1 ±2.1 cm H2O. Further reduction of nasal CPAP induced snoring in 15 patients and obstructive apnoea in five patients with the latter accompanied by a severe reduction of SpO2 (87.4 ± 6.1%). Patients with apnoea were older than those who snored (P < 0.05). We conclude that upper airway obstruction contributes considerably to decreases in SpO2 during midazolam sedation for spinal anaesthesia. 相似文献
975.
Hiroshi Okada Noboru Tatsumi Masanori Kanzaki Masato Fujisawa Soichi Arakawa Sadao Kamidono 《The Journal of urology》1997,157(6):2140-2146
Purpose
We determined the incidence of reactive oxygen species formation by spermatozoa from asthenospermic patients, and the relationship between reactive oxygen species formation and sperm motion parameters. We also assessed the efficacy of in vitro and in vivo pentoxifylline treatment of asthenospermic patients whose spermatozoa generated high reactive oxygen species levels.Materials and Methods
Reactive oxygen species formation by spermatozoa from asthenospermic patients and fertile volunteers was measured by chemoluminescence. Reactive oxygen species formation by the sperm preparations was investigated without stimulation (steady state), or after stimulation with N-formyl-methionyl-leucyl-phenylalanine (f-MLP) or phorbol-12-myristate-13-acetate. Spermatozoa from 15 asthenospermic patients whose spermatozoa produced high levels of reactive oxygen species at steady state were treated in vitro with pentoxifylline to determine its effect on reactive oxygen species generation and sperm motion parameters. These same 15 patients and 18 with asthenospermia whose spermatozoa did not produce reactive oxygen species at steady state were treated with pentoxifylline at 2 different dosages (300 and 1,200 mg. daily) to determine its effect on reactive oxygen species generation, sperm motion parameters and sperm fertilizing ability in vivo.Results
When reactive oxygen species formation was detected in the steady state that was not stimulated by f-MLP, the source of reactive oxygen species could be attributed to the spermatozoa themselves. Spermatozoa from 15 of 71 asthenospermic patients generated reactive oxygen species at steady state. Pentoxifylline decreased reactive oxygen species generation by spermatozoa in these patients, and preserved the decrease of curvilinear velocity and beat cross frequency for 6 hours in vitro. For these patients orally administered pentoxifylline failed to decrease reactive oxygen species generation by spermatozoa, and had no effect on sperm motility, sperm motion parameters and sperm fertilizing ability at low dosage (300 mg. daily). However, it increased motility and beat cross frequency at high dosage (1,200 mg. daily) but it had no effect on sperm fertilizing ability.Conclusions
Stimulation of sperm preparations with f-MLP can identify the source of reactive oxygen species generated at steady state. Among asthenospermic patients there were some whose spermatozoa produced detectable steady state levels of reactive oxygen species. In this group pentoxifylline appeared to be effective for decreasing reactive oxygen species formation and preserving sperm motion parameters in vitro. Orally administered pentoxifylline had no effect at low dosage but it increased sperm motility and some sperm motion parameters without altering sperm fertilizing ability at high dosage. 相似文献976.
Kawahara F Noguchi M Yamamichi N Konishi F Yagasaki R Minami M Earashi M Kinoshita K Taniya T Miyazaki I 《Breast cancer (Tokyo, Japan)》1997,4(1):43-48
Two cases of carcinoma involving ectopic breast tissue are reported, along with a review of the Japanese literature. A total
of 65 cases of ectopic breast cancer have been reported; 59 of which occurred in the axilla. Total mastectomy with axillary
dissection was performed in 29 cases, and tumor excision with or without nodal dissection was done in 30 cases. Outcome was
known in 33 cases, and 5 cases had recurred at the time of this writing. Although the prognosis of ectopic breast cancer was
difficult to establish with the limited follow-up data, all the 5 cases in our series with recurrence had axillary lymph node
metastases at the time of surgery. Therefore, the complete excision of ectopic breast tissue with nodal dissection, and subsequent
chemoendocrine therapy, especially in node-positive patients, is recommended as the treatment of choice. 相似文献
977.
Sakai H Nakashima S Nakatani K Yoshimura S Nishimura Y Sakai N Nozawa Y 《Brain tumor pathology》1997,14(2):119-123
To identify differentially expressed genes involved in rat C6 glioma cell differentiation induced by cyclic AMP, we adopted
mRNA fingerprinting using arbitrarily primed polymerase chain reaction (PCR) (RAP). Four complementary DNA (cDNA) fragments
differentially expressed during differentiation were isolated, and they appeared to contain coding regions of corresponding
mRNAs. RAP can be used to efficiently identify cDNA fragments by comparing nucleotide and deduced amino acid sequences with
those in databases, and is thus a useful method to search for and identify important genes involved in complex cellular processes
such as glioma cell differentiation. 相似文献
978.
979.
Yuichi Kasai Mitsuru Fukui Kazuhisa Takahashi Seiji Ohtori Daisaku Takeuchi Hiroshi Hashizume Masahiko Kanamori Noboru Hosono Tsukasa Kanchiku Eiji Wada Miho Sekiguchi Shinichi Konno Mamoru Kawakami 《Journal of orthopaedic science》2017,22(4):665-669
Background
Validity and reliability of the Japanese Orthopaedic Association Back Pain Evaluation Questionnaire (JOABPEQ) had already been verified as the patients' self-rating assessment of low back pain and lumbar spinal disease and, the present study demonstrated the responsiveness of this measure.Methods
192 subjects who were determined by medical instructors of the Japanese Society for Spine Surgery and Related Research were analyzed. They had completed a series of treatment and both surveys before and after the treatment. Authors investigated rates of concordance between assessment by physicians and subjective assessment by patients. The mean, standard deviation, minimum, 25th percentile, median, 75th percentile and maximum values for pre-treatment, post-treatment, and acquired points were calculated, and then, we also investigated the trend between subjective assessment by patients and mean acquired points for each JOABPEQ domain and substantial clinical benefit thresholds for the JOABPEQ.Results
Symptom changes as assessed by physicians did not coincide with those by patients, and acquired points in each JOABPEQ domain were significantly increased with improved self-rating by patients. In addition, patients who rated symptom changes as “slightly improved” showed a mean acquired points of ≥20, and those reporting “improved” showed a 25th percentile points of the acquired points of ≥20 approximately.Conclusion
A significant correlation was noted between the self-rating of patients and acquired points JOABPEQ, suggesting that ≥20 acquired points can be interpreted as substantial clinical benefit thresholds for the JOABPEQ. 相似文献980.
Masayuki Inoue Tatsunori Ikemoto Shinsuke Inoue Masatoshi Nakata Makoto Nishihara Young-Chang P. Arai Hirofumi Miyagawa Kazuhiro Shimo Hiroki Iida Tomomi Hasegawa Toshiko Wakabayashi Hiroki Sakurai Yoshinobu Hasegawa Keiko Owari Noboru Hatakeyama Takahiro Ushida 《Journal of orthopaedic science》2017,22(6):1132-1137