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1.
陈晓光  大谷周造  李燕  韩锐 《药学学报》1998,33(11):821-827
目的旨在寻找新型抗肿瘤药物,进一步研究d-宁烯、丹参及姜黄素衍生物的抗肿瘤机理。采用分子生物学方法及划痕标记染料示踪技术,研究了4种人实体瘤起源的细胞系的细胞间隙信息传导(GJIC)、H-ras癌基因表达以及ras癌基因产物(P21ras蛋白)表达状态,并观察了4种天然产物对它们的影响。结果表明,细胞内染料传输功能的丧失与ras基因突变率呈正相关;单萜化合物d-宁烯和酚类化合物丹参衍生物的抗肿瘤作用可能与抑制P21ras蛋白膜结合和增强细胞间隙信息传导功能有关。提示Ras癌基因产物P21ras蛋白膜结合的抑制与细胞间隙信息传导功能的增强有直接关系。  相似文献   
2.
During the past 4 years, the performances of various tumor markers such as CA15-3, CEA, ferritin, beta 2-microglobulin and TPA have been evaluated in 78 cases of mammary cancer. The results were categorised according to differences in stages, difference in values from patients with recurrent tumors, the incidence of abnormal values and differences in values before and after surgery. When the incidence of values higher than the cutoff value was determined for each of stage I, II and III + IV, the rates for CEA were 14.3%, 4.9% and 27.8%, respectively, whereas those for TPA were 25.0%, 22.2% and 26.7%, respectively. In addition, for CA15-3, the incidences were 0% in stage I, 5.0% in stage II and 57.1% for combined stages III + IV. The average values for patients with recurrent tumors were 3.2 ng/ml CEA, 194.5 ng/ml ferritin, 316.2 U/l TPA and 81.3 U/ml CA15-3. The rates of abnormal values were 40.0% for CEA, 40.0% for ferritin, 85.7% for TPA and 63.6% for CA15-3. Differences in the values after surgical removal of the tumor were observed with these tumor markers: the CEA value was reduced from 1.6 +/- 1.4 to 1.1 +/- 0.5 (p less than 0.01) and the CA15-3 value from 12.2 +/- 8.4 to 9.3 +/- 4.1 (p less than 0.05), respectively, whereas that for ferritin was conversely increased from 48.9 +/- 48.0 to 74.0 +/- 70.0 (p less than 0.01). However, the values for TPA, despite showing a tendency to decrease, did not show any statistically significant alteration. The fluctuations of these marker levels in patients with recurrent tumors reflects the progress of the disease, with a sudden elevation in values indicating imminent death. The diagnostic significance of these markers is not high, but they are considered to be useful in detecting the progress or condition of a recurrent tumor.  相似文献   
3.
We examined the activity of spermidine/spermine N 1-acetyltransferase (SAT), a rate-limiting enzyme of the biodegradation of polyamines, in N -butyl- N -(4–hydroxybutyI)nitrosamine-induced transitional cell carcinoma (TCC) and melamine-induced papillomatosis of rat bladder, and compared the activity to that of ornithine decarboxylase (ODC). Both activities were higher in both lesions than in control rats. The difference between SAT and ODC activities in cancerous tissue and papillomatosis was not significant. Cells stained for proliferating cell nuclear antigen (PCNA) were abundant in papillomatosis. TCC had areas with much PCNA. The results indicated that an elevation of SAT activity occurs in both reversible and irreversible proliferation of bladder epithelium and could be important in bladder carcinogenesis.  相似文献   
4.
Background: The aim of this study was to investigate the effects of two imidazoline-derived intravenous anesthetics, etomidate and midazolam, on vascular adenosine triphosphate-sensitive potassium (KATP) channel activity.

Methods: In isolated rat aorta, isometric tension was recorded to examine the anesthetic effects on vasodilator response to levcromakalim, a selective KATP channel opener. Using the patch clamp method, the anesthetic effects were also examined on the currents through (1) native vascular KATP channels, (2) recombinant KATP channels with different combinations of various types of inwardly rectifying potassium channel (Kir6.0 family: Kir6.1, 6.2) and sulfonylurea receptor (SUR1, 2A, 2B) subunits, (3) SUR-deficient channels derived from a truncated isoform of Kir6.2 subunit (Kir6.2[DELTA]C36 channels), and (4) mutant Kir6.2[DELTA]C36 channels with reduced sensitivity to adenosine triphosphate (Kir6.2[DELTA]C36-K185Q channels).

Results: Etomidate (>= 10-6 m), but not midazolam (up to 10-6 m), inhibited the levcromakalim-induced vasodilation, which was sensitive to glibenclamide (IC50: 7.21 x 10-8 m; maximum inhibitory concentration: 1.22 x 10-4 m). Etomidate (>= 3 x 10-6 m), but not midazolam (up to 10-4 m), inhibited the native KATP channel activity in both cell-attached and inside-out configurations with IC50 values of 1.68 x 10-5 m and 1.52 x 10-5 m, respectively. Etomidate (10-5 m) also inhibited the activity of various types of recombinant SUR/Kir6.0KATP channels, Kir6.2[DELTA]C36 channels, and Kir6.2[DELTA]C36-K185Q channels with equivalent potency.  相似文献   

5.
6.
Olfactory stimulation evokes a column of activity within the olfactory bulb extending from the glomerular layer to the granule cell layer that can be visualized with 2-deoxyglucose autoradiography, optical imaging, Fos protein immunohistochemistry and c-fos mRNA in situ hybridization. The Fos response to odors is typified by the activity of relatively few juxtaglomerular cells, which often occur in foci, and a large number of granule cells extending through much of the bulb. In this study, we characterized the granule cell response to an odor for which young rats had acquired a preference. Fos-like immunoreactive granule cells were quantified by image analysis, and densely stained cells were counted in a region previously shown to be responsive to peppermint odor. We found that odor-trained pups have about half the number of Fos-immunopositive superficial granule cells which respond to a learned odor than do control pups. We then determined whether there was a correlation between the juxtaglomerular cell response and the response of the superficial granule cells deep to those glomerular layer cells. We found a positive correlation between the number of juxtaglomerular cells and the number of granule cells demonstrating Fos immunoreactivity in both control and trained pups, a relationship that changed with early olfactory training.  相似文献   
7.
We performed human leukocyte antigens(HLA)typing for class I antigens on 19 Japanese patients with Fisher's syndrome. We demonstrated a statistically significant association between the disease and the HLA-B39 antigen.  相似文献   
8.
The synthesis of methyl methacrylate/styrene copolymer bearing overwhelmingly bromine and the 2-carbomethoxyallyl group (CH2?C(COOCH3)CH2? ) at the α- and ω-termini instead of the fragment of the initiator with reduced molecular weight was investigated by using methyl α-(bromomethyl)acrylate as chain transfer agent through the addition-fragmentation mechanism. The molecular weight of the copolymer was effectively decreased with bromomethylacrylate, and the unsaturated end groups quantitatively bound to two types of the monomeric units were differentiated by means of 1H NMR spectroscopy. Equations estimating the reactivities of methyl α-(bromomethyl)acrylate towards polystyrene and poly(methyl methacrylate) radicals were derived. Methyl α-(bromomethyl)acrylate was found to be more reactive toward the poly(methyl methacrylate) radical than the polystyrene radical by a factor of 0,62.  相似文献   
9.
Summary The purpose of the present study was to evaluate the relationship between several physical fitness parameters and eyesight divided into 3 grades in visually handicapped boys and young male adults, and to investigate the effect of mild exercise training on physical and psychic symptoms as well as cardiorespiratory fitness. Four subjects were totally blind (TB), 6 were semi-blind (SB) and 27 had amblyopia (AM). Physical fitness tests consisted of maximal oxygen uptake (V O 2max), maximal pedalling speed and power, maximal stepping rate, and isometric knee extention strength. Compared with AM and SB groups, the TB group was inferior in all physical fitness parameters. Especially,V O 2max in TB (26 ml · kg–1 · min–1) was about 56% of that in agematched Japanese sighted subjects and was significantly low compared with the AM and SB groups. Both muscle strength and maximal pedalling power corresponded to about 50% that of the age-matched sighted group. Six SB and 4 TB students (¯x=17.7 years) were trained for 6 weeks on a bicycle ergometer at an intensity of 50%V O 2max. Training was undertaken for 3 days per week and maintained for 60 min per session. After training, physical and psychic symptoms determined by the Cornell Medical Index improved significantly. These results indicate that low physical work capacity in visually handicapped boys and young male adults is due to the lack of physical activity, and that mild endurance training is effective in improving physical and psychic symptoms as well as cardiorespiratory fitness.  相似文献   
10.
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