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排序方式: 共有673条查询结果,搜索用时 15 毫秒
1.
H Van Dekken E W Schervish J G Pizzolo W R Fair M R Melamed 《The Journal of pathology》1991,164(1):17-22
We have used fluorescent in situ hybridization and simultaneous in vivo bromodeoxyuridine labelling of a solid bladder cancer to examine tumour cell subsets for possible proliferative growth differences. In this dual-labelled preparation, most tumour cell nuclei exhibited monosomy 9, consistent with reported karyotypes of bladder cancer. Incorporated bromodeoxyuridine was visualized with a fluoresceinated antibody in 5-6 per cent of the tumour cells, concordant with S-phase estimates by cell cycle analysis of the flow cytometric DNA histogram. A majority of the bromodeoxyuridine-positive cells also carried the monosomy 9 chromosome abnormality. This is the first report to demonstrate the feasibility of combined in situ hybridization and detection of bromodeoxyuridine incorporated in vivo in human tumour cells in order to provide information on the growth rate of specific subsets of tumour cells identified by chromosomal constitution. 相似文献
2.
Toshiaki Moriki Tamotsu Takahashi Makoto Hiroi Toshiko Yamane Hiroshi Hara 《Pathology international》1996,46(6):417-425
Thirty cases of invasive ductal carcinoma of the breast were classified to histological subtype according to the General Rules for Clinical and Pathological Recording of Breast Cancer of the Japanese Breast Cancer Society and histologically graded using the Nottingham method and the correlation of histology with proliferative activity was investigated using bromodeoxyuridine (BrdU). In addition, the overexpression of p53 protein, c-erbB-2 oncoprotein and estrogen receptor (ER) were immunohistochemically examined in order to discuss the relationship with histological subtype and histological grade. Histological grade correlated positively to the BrdU labeling index (LI) and overexpression of p53. High grade carcinoma demonstrated c-erbB-2 more frequently and exhibited a low incidence of ER. However, no significant relationship was found between BrdU LI, overexpression of p53 and c-erbB-2 and histological subtype. These results suggest that the histological grade does represent the proliferative activity of tumor cells and that adding the histological grade to the pathological diagnosis in invasive ductal breast carcinoma may be useful from the clinicopathological aspect concerning tumor behavior. 相似文献
3.
It has recently been shown that hippocampal neurogenesis can be modulated either directly or indirectly by ascending cholinergic inputs from the basal forebrain. In the present work, we sought to address whether extended training in a spatial navigation task would affect hippocampal neurogenesis in the presence of a severe and selective cholinergic depletion. Young female rats received stereotaxic injections of the immunotoxin 192 IgG-saporin into the basal forebrain nuclei and/or the cerebellar cortex. Starting from 4 to 5 weeks post-lesion, and for the subsequent 2 weeks, the animals were trained on paradigms of reference and working memory in the water maze and received single daily i.p. injections of bromodeoxyuridine (BrdU) at the end of each testing session. In line with previous observations, a dramatic 80% decrease in neuron proliferation was seen in the dentate gyrus of lesioned animals, as compared to vehicle-injected or intact controls. Interestingly, however, rats subjected to maze training over 2 weeks, irrespective of their learning success, exhibited significantly fewer newborn neurons than matched controls with no maze exposure. Thus, at least for the type of task used here, which has previously been shown to impose a certain degree of stress, extended training and learning does not appear to affect proliferation in the dentate gyrus. 相似文献
4.
局灶性脑缺血大鼠皮质和尾壳核神经干细胞增殖分化与nNOS的表达 总被引:1,自引:1,他引:1
本研究旨在探讨局灶性脑缺血再灌注大鼠皮质和尾壳核神经干细胞的增殖分化与nNOS表达的关系。大脑中动脉线栓法制作大鼠局灶性脑缺血再灌注模型,5溴脱氧尿核苷(BrdU)标记分裂增殖细胞,免疫组化单标和双标记技术检测各组大鼠缺血侧皮质和尾壳核BrdU阳性细胞和nNOS的表达。模型组大鼠皮质和尾壳核BrdU阳性细胞再灌注后3d开始增多,14d达高峰,nNOS阳性细胞再灌注后7d表达增强,28d达高峰,BrdU/nNOS双标细胞在14d达高峰,占皮质BrdU阳性细胞数的42.95%,尾壳核内占42.56%。新生细胞分化组BrdU阳性细胞和BrdU/nNOS双标细胞显著多于模型组(P<0.05),皮质双标细胞占BrdU阳性细胞数的54.08%,尾壳核内占47.84%。提示局灶性脑缺血可增强大鼠皮质和尾壳核的增殖能力,部分增殖细胞分化为nNOS阳性神经元,参与神经网络的重建。 相似文献
5.
Hideo Yamane Takayuki Nakagawa Hiroyoshi Iguchi Shigetarou Shibata Masahiro Takayama Kishiko Sunami Yoshiaki Nakai 《Auris, nasus, larynx》1997,24(3):221-225
We performed an in vitro study in order to determine possible triggers of hair cell regeneration in the chick basilar papilla following degeneration. We compared the response of sensory epithelium damaged by collagenase treatment with that damaged by acoustic trauma. The former exhibited no proliferative activity, but the latter did. The basilar papillae damaged by acoustic trauma could have proliferating activity in medium containing fetal bovine serum (FBS) or epidermal growth factor (EGF) but not in the medium without FBS or EGF. These findings indicate that regeneration of basilar papillae depends on the manner of cell death and that FBS or EGF is required for regeneration. 相似文献
6.
BrdU-ELISA法测定四逆汤及组方药提取物对大鼠血管平滑肌细胞增殖的影响 总被引:3,自引:0,他引:3
目的 观察四逆汤(SNT)及组方药提取物对大鼠主动脉血管平滑肌细胞(VSMC)增殖的影响。方法 采用MTT比色法和Brdu—ELISA法观察药物对离体大鼠VSMC增殖的影响。结果 BrdU—ELISA法结果表明四逆汤总提取物(EST)对VSMC的BrdU掺入DNA没有显著影响,而MTT测定表明:EST可以提高VSMC的脱氢酶活性。甘草(LE)、附子(AE)、干姜(GE)、甘草加附子(LAE)、干姜加附子(AGE)提取物显著提高VSMC的脱氢酶活性,同时提高VSMC的BrdU掺入DNA的水平。结论 EST可以增加VSMC的脱氢酶活性,但对VSMC的BrdU掺入DNA的水平无影响。而其他组方药提取物可以增加VSMC的脱氢酶活性,同时提高VSMC的BrdU掺入DNA的水平。 相似文献
7.
《Pharmaceutical biology》2013,51(8):1098-1103
AbstractContext: Chrysanthemum zawadskii var. latilobum (Asteraceae) (CZ) and Polygonum multiflorum Thunb. (Polygonaceae) (PM) have been used traditionally to treat different systemic diseases and acclaimed for various biological activities including hair growth.Objective: This study investigates the hair restoration efficacy of selected medicinal plant extracts on nude mice.Materials and methods: Nude mice genetically predisposed to pattern balding were used in this study. Topical methanol extracts of CZ and PM (10?mg/mouse/d) with standardized vehicle formulation, only vehicle (propylene glycol:ethanol:dimethyl sulfoxide, 67:30:3% v/v) and Minoxidil (2%) were applied daily for 40 consecutive days.Results: In our study, the maximum hair score (2.5?±?0.29) was obtained in the CZ-treated group. Histological observation revealed a significant increase (p?<?0.001) in the number of hair follicles (HF) in CZ-treated mice (58.66?±?3.72) and Minoxidil-treated mice (40?±?2.71). Subsequently, immunohistochemical analysis also confirmed the follicular keratinocyte proliferation by detection of BrdU-labeling, S-phase cells in Minoxidil and CZ-treated mouse follicular bulb and outer root sheaths.Conclusion: Our study revealed the underlying mechanism of stimulating hair growth in athymic nude mice by repair the nu/nu follicular keratin differentiation defect. Thus, the topical application of CZ may represent a novel strategy for the management and therapy of certain forms of alopecia. 相似文献
8.
New neurons are incorporated into the adult brains of a variety of organisms, from humans and higher vertebrates, to non-vertebrates such as crustaceans. In virtually all of these systems serotonergic pathways appear to provide important regulatory influences over the machinery producing the new neurons. We have developed an in vitro preparation where adult neurogenesis can be maintained under highly controlled conditions, and are using this to test the influence of hormones on the production of neurons in the crustacean (Homarus americanus) brain. Serotonin levels have been manipulated in this in vitro preparation, and the resulting effects on the rate of neurogenesis have been documented. In addition we have compared in vitro influences of serotonin with results acquired from in vivo exposure of whole animals to serotonin. These experiments suggest that there are multiple mechanisms and pathways by which serotonin may regulate neurogenesis in the crustacean brain: (1) serotonin is effective in regulating neurogenesis at levels as low as 10−10 M, suggesting that circulating serotonin may have hormonal influences on neuronal precursor cells residing in a vascular niche or the proliferation zones; (2) contrasting effects of serotonin on neurogenesis (up- vs. down-regulation) at high concentrations (10−4 M), dependent upon whether eyestalk tissue is present or absent, indicate that serotonin elicits the release of substances from the sinus glands that are capable of suppressing neurogenesis; (3) previously demonstrated (Beltz, B.S., Benton, J.L., Sullivan, J.M., 2001. Transient uptake of serotonin by newborn olfactory projection neurons. Proc. Natl. Acad. Sci. USA 98, 12730-12735) serotonergic fibers from the dorsal giant neuron project directly into the proliferation zone in Cluster 10, suggest synaptic or local influences on neurogenesis in the proliferation zones where the final cell divisions and neuronal differentiation occur. Serotonin therefore regulates neurogenesis by multiple pathways, and the specific mode of influence is concentration-dependent. 相似文献
9.
10.
Microbial detoxification of deoxynivalenol (DON) represents a new approach to treating DON-contaminated grains. A bacterium Devosia mutans 17-2-E-8 was capable of completely transforming DON into a major product 3-epi-DON and a minor product 3-keto-DON. Evaluation of toxicities of these DON-transformation products is an important part of hazard characterization prior to commercialization of the biotransformation application. Cytotoxicities of the products were demonstrated by two assays: a MTT bioassay assessing cell viability and a BrdU assay assessing DNA synthesis. Compared with DON, the IC50 values of 3-epi-DON and 3-keto-DON were respectively 357 and 3.03 times higher in the MTT bioassay, and were respectively 1181 and 4.54 times higher in the BrdU bioassay. Toxicological effects of 14-day oral exposure of the B6C3F1 mouse to DON and 3-epi-DON were also investigated. Overall, there were no differences between the control (free of toxin) and the 25 mg/kg bw/day or 100 mg/kg bw/day 3-epi-DON treatments in body and organ weights, hematology and organ histopathology. However, in mice exposed to DON (2 mg/kg bw/day), white blood cell numbers and serum immunoglobulin levels were altered relative to controls, and lesions were observed in adrenals, thymus, stomach, spleen and colon. Taken together, in vitro and in vivo studies indicate that 3-epi-DON is substantially less toxic than DON. 相似文献