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81.
John T. Leith 《The Prostate》1994,24(3):119-124
Because there is extremely limited information on the intrinsic radiosensitivity of human prostatic cancer cells, we have investigated the in vitro radiation response of exponentially growing LNCaP cells. Due to the very poor colony-forming potential of the LNCaP cells, radiation survival was investigated using the dose-dependent (0-6 Gy) changes seen after X-irradiation in the shapes of regrowth curves. Survival was described using both the single-hit, multitarget (SHMT) equation and the linear-quadratic (LQ) equation. The values and 95% confidence limits of the extrapolation number (n), quasi-threshold dose (Dq), and mean lethal dose (Do) in SHMT terminology were respectively: 0.9 (0.7-1.0), 0.0 Gy, and 1.39 (0.11) Gy. The LQ alpha and beta parameters were respectively 6.80 (1.13) and -0.53 (2.89). The X-ray dose response of the LNCaP line is, therefore, purely exponential. The mean survival at the clinically relevant dose of 2 Gy (S2) was 51.2% for the LNCaP line. Comparison of the S2 value for the LNCaP line with previous investigations with other human prostatic cancer cell lines (DU145 and PC-3) indicates a mean S2 value of 47.6%, which suggests that human prostate cancer cells might lie toward the resistant side of the spectrum for various classes of human neoplasms. © 1994 Wiey-Liss, Inc. 相似文献
82.
E. Alsat PhD J. Guibourdenche PhD D. Luton MD F. Frankenne PhD D. Evain-Brion MD PhD 《American journal of obstetrics and gynecology》1997,177(6):1526-1534
Placental growth hormone is the product of the GH-V gene specifically expressed in the syncytiotrophoblast layer of the human placenta. Placental growth hormone differs from pituitary growth hormone by 13 amino acids. It has high somatogenic and low lactogenic activities. Assays by specific monoclonal antibodies reveal that in the maternal circulation from 15 to 20 weeks up to term placental growth hormone gradually replaces pituitary growth hormone, which becomes undetectable. It is secreted by the placenta in a nonpulsatile manner. This continuous secretion appears to have important implications for physiologic adjustment to gestation and especially in the control of maternal insulin-like growth factor-I levels. Placental growth hormone secretion is inhibited by glucose in vitro and in vivo and is significantly decreased in the maternal circulation in pregnancies with intrauterine growth restriction. Placental growth hormone does not appear to have a direct effect on fetal growth because this hormone is not detectable in the fetal circulation. However, the physiologic role might also include a direct influence on placental development through an autocrine or paracrine mechanism, as suggested by the presence of specific growth hormone receptors in this tissue.(Am J Obstet Gynecol 1997;177:1526-34.) 相似文献
83.
Ralf Henkel Susan Cooper Khalied Kaskar Wolf-Bernhard Schill Ursula-F. Habenicht Daniel R. Franken 《Journal of assisted reproduction and genetics》1995,12(9):644-649
Purpose
A total of 86 fresh and salt-stored immature human oocytes derived from postmortem ovarian tissue were used for this study.Methods
Oocytes were randomly incubated either in synthetic human tubal fluid medium (untreated zonae) or in a chemically defined medium (treated zonae).Results
Sperm binding experiments using hemizona assay conditions exhibited a 10-fold increased binding of sperm to treated compared to untreated oocytes (272.7±43 versus 24.3±15 sperm bound, respectively; P<0.0001). pH recordings during incubation showed elevated pH levels of 8.1 compared to pH 7.2 among treated and untreated zonae, respectively. Ultrastructural examination showed a spongy appearance of the surface of treated zonae, whereas untreated zonae appeared compact with smooth surface.Conclusions
The marked increase in sperm binding among treated zonae, together with the ultrastructural findings, suggest that the altered zona surface enhances sperm binding. The physiological maturational process of the zona pellucida might be manipulated in vitro, thus increasing sperm binding to the zona.Presented at the IXth World Congress on In Vitro Fertilization and Alternate Assisted Reproduction, April 3–7, 1995. Vienna, Austria. 相似文献
84.
85.
Summary. The present study was carried out to investigate the predictive value of the percentage of sperm motility after 24-h incubation and sperm survival ratio from semen and inseminated sperm suspension using grading of motility by WHO criteria with respect to the fertilization of oocytes in vitro. A total of 789 oocytes from 85 cases were inseminated and the mean fertilization rate obtained was 72.5%. There was no significant correlation between all of the sperm motility results with fertilization rate in vitro. All sperm motility results were not significantly different between the non-fertilizing group and the fertilizing group and also between the group of fertilization rate ≤ 25th percentile (fertilization rate ≤62.5%) and the group of fertilization rate >62.5%. However, the initial percentage of rapid progressive sperm motility and progressive motility in semen and inseminated sperm suspension at 24 h gave significant differences between the group of fertilization ≤ 50th percentile (fertilization rate ≤80%) and the group of fertilization rate >80%. Overall accuracy using these parameters for prediction of fertilization rate >80% was only about 60%. In conclusion, the percentage of sperm motility at 24 h and sperm survival ratio in both semen and inseminated sperm suspension have no practical value in predicting fertilization rate in vitro. Moreover, detailed motility grading cannot improve the predictivity of these sperm motility parameters. 相似文献
86.
Ida-Marie Stender Takafumi Etoh Tetsuya Tsuchida Hidemi Nakagawa H. Randolph Byers Genji Imokawa Yasumasa Ishibashi 《The Journal of dermatology》1993,20(10):611-617
The ability of the human amelanotic melanoma cell line MM-RU to produce experimental metastases and to grow tumors at subcutaneous inoculation sites in 4-week-old nude mice was examined. After i.v. inoculation of 106 cells, all injected mice (n=21) developed consistent numbers of metastatic pulmonary colonies within 32 days. The coefficients of variation for the number of colonies were between 17%–23% in three independent experiments. Survival time after i.v. inoculation was 63 ± 7 days (mean ± SD) (n=20). Within 20 days, subcutaneous inoculation of 5 × 106 cells resulted in tumor growths of 13 ± 3 mm (mean ± SD) at the inoculation sites in all nude mice (n=12). The MM-RU cell line seems to be a simple, fast vehicle for testing the effect of melanoma growth modulators on experimental pulmonary metastases as well as on subcutaneously growing melanoma. 相似文献
87.
Summary Epidermal growth factor (EGF) has been shown to stimulate DNA synthesis and cell division in normal glia. At least half of malignant human gliomas (MHG) express high levels of the EGF receptor (EGFR), which are above those detected in normal brain. The demonstration that antibodies against the EGFR inhibit the growth of squamous cell carcinoma line A-431, with large numbers of EGFR, in vitro and in vivo raises the possibility that these agents could be used therapeutically against malignant human gliomas either alone or conjugated to other agents. We have measured the growth effects of EGF and an anti-EGFR monoclonal antibody, 528 (Ab-528), on four well-characterized human malignant glioma cell lines, D-263 MG, D-247 MG, U-343 MGa Cl 26, and D-37 MG, with 2.9×104, 1.5×105, 8.6×105 and 1.59×106 EGFRs per cell, respectively. EGF significantly increased cell number in D-263 MG and D-37 MG by 65% and 74%, respectively, had no effect on D-247 MG, and significantly decreased cell number in U-343 MGa Cl 26 by 39%. U-343 MGa Cl 26 growth was inhibited 19% by Ab-528, but Ab-528 had no effect on growth of the other MHG lines. Ab-528 significantly inhibited all EGF-mediated growth effects. These studies demonstrate that, although Ab-528 alone has little antiproliferative activity on MGH, it successfully competes with EGF to reduce the biological effects of EGF-EGFR binding. Therefore, this antibody could potentially be used to target radioisotopes to MHG via the EGFR for diagnosis and therapy.Supported by Grants CA-11898, NS-20023, CA-43722, and the Association for Brain Tumor Research (MHW, PAH) 相似文献
88.
Josephine Shallo-Hoffmann Dirk Watermeier Jürgen Petersen Hermann Mühlendyck 《Neurosurgical review》1988,11(2):151-158
Verification of inheritance in congenital nystagmus (CN) is only possible through the identification of more than one affected member in a family, since in a single case there are no accurate clinical differentiations between spontaneous and inherited CN. We performed electronystagmographic examinations (ENG) to search for abnormal involuntary eye movements as a sign of heredity in seemingly unaffected members of CN families.ENG registrations were performed under three test conditions: (1) with the subject fixating a target, (2) with the room lights off and (3) with closed eyes.Fifty normally sighted individuals (group (a) underwent the test procedure to provide a baseline of normality. Five CN families (three dominant, two sex-linked recessive) were tested as group (b). The eye movement recordings were analysed in terms of nystagmus intensity (amplitude x frequency of the involuntary saccade). In every one of the five families, abnormalities in seemingly non-affected members could be demonstrated: in four families, fastphase instabilities, in the fifth family a true (CN) (slowphase instability).All certain gene carriers were diagnosed correctly by the ENG.These findings indicate a method for detecting slightly affected members in dominant pedigrees and female gene carriers in sex-linked mode of transmission. 相似文献
89.
Human slow-wave sleep and the cerebral cortex 总被引:1,自引:1,他引:0
Horne J 《Journal of sleep research》1992,1(2):122-124
SUMMARY Recent hypotheses about the roles of human slow-wave sleep (hSWS—delta EEG activity) are appraised. The possible linkage between hSWS and the functions of the prefrontal cortex (PFC) are explored with respect to normal subjects and to disorders involving PFC deficits. 相似文献
90.
"Necklace olfactory glomeruli" form unique components of the rat primary olfactory system 总被引:3,自引:0,他引:3
A distinct subset of rat primary olfactory neurons was identified immunohistochemically by means of a polyclonal antibody against human placental antigen X-P2 (hPAX-P2), an incompletely characterized substance found in all estrogen-biosynthetic organs. The subset of olfactory receptor cells was distributed widely over the olfactory epithelium with some degree of concentration on the dorsocaudal walls of nasal subcavities. The subset formed unique "necklace olfactory glomeruli," which were composed of seven to nine solitary glomeruli located in the caudal end of the olfactory bulb. One of them was located in the "modified glomerular complex" reported to be involved in rat suckling behavior. The projectional patterns of the necklace olfactory system, albeit diffuse, indicated some degree of spatial correspondence between zones of olfactory epithelium and specific glomeruli. Axons emanating from neighboring cells can project to several glomerular loci. From the necklace olfactory system, an average of 150-200 receptor cells were estimated to converge onto a single necklace glomerulus. 相似文献