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21.
A study was performed to evaluate the cytologic criteria for recognizing endometrial cancer and to determine the accuracy of endometrial aspiration in its detection. In addition to the conventional cytologic criteria for the diagnosis of endometrial cancer, the irregular chromatin distribution around the macronucleoli proved to be a useful criterion. Using all criteria, cytology was reported as positive in 18 of 19 patients (94.7%) with endometrial cancer. In 856 of 12,563 high-risk outpatients at Kinki University Hospital, aspiration using the Masubuchi apparatus was carried out in screening for endometrial cancer. Cancer was detected in 18 patients (2.1%), with 94.7% of the cancers detected by the cytologic screening. This result indicates that endometrial aspiration using the Masubuchi apparatus is a reliable and safe method of screening for endometrial cancer. 相似文献
22.
The head shell of bacteriophage lambda expands by about 20% in diameter when it packages the DNA molecule in vivo. The expansion reaction is essentially a conformational change of the major head protein molecules to a state of lower free energy and can also be triggered in vitro by treatment with 4 M-urea. In order to investigate the conformational change, we have measured the circular dichroism, fluorescence and difference absorption spectra of the lambda head shell before and after the expansion by the treatment with urea. The far-ultraviolet circular dichroism spectra and the fluorescence spectra show that the expansion is not accompanied by a great change in the secondary structure (29% alpha-helix, 23% beta-structure) and the environment (non-polar) of the tryptophan residues of the major head protein molecule. On the other hand, by measurements of the circular dichroism and difference absorption spectra in the near-ultraviolet region as well as by chemical modification experiments with tetranitromethane, we have found that one or two tyrosine residues of the major head protein are transferred from a polar, solvent-exposed to a non-polar, solvent-unexposed environment during the expansion. Judging from these results, the conformational change seems to be mainly intermolecular or interdomainal rather than intradomainal. 相似文献
23.
We have studied ouabain-resistant, external sodium-stimulated, lithium efflux (LiNa countertransport) in red blood cells from 21 borderline hypertensives with at least one hypertensive first degree relative (BH-F), 19 borderline hypertensives without family history of essential hypertension (BH-NF), and 35 age-matched normotensive subjects. The data indicate the finding of an increased LiNa countertransport in all BH (F+NF), but with a significant overlap between BH values and control ones: LiNa countertransport is significantly higher only in BH-F but it is normal in BH-NF. Moreover, there is a significant correlation of LiNa countertransport to total peripheral resistance but not to mean blood pressure in all hypertensive patients. It is suggested that in BH the increase of erythrocyte Na flux is mediated by the NaNa exchange diffusion, and its abnormality may be associated to the hereditary trait of essential hypertension rather than the high blood pressure per se, probably resulting in the development of hypertension, through the increased vascular smooth muscle tone. 相似文献
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The number of circulating haemocytes, the size of the haematopoietic organ, and the size of haemocyte capsules around the parasite were studied in M-line Biomphalaria glabrata snails exposed to 100 or 400 first-stage larvae of Angiostrongylus cantonensis. The number of haemocytes in exposed snails increased significantly at 1 day post-exposure, decreased to control value, and then increased again. The decrease in number of circulating haemocytes is probably due to the removal of cells from the circulation to participate in encapsulation of larvae. The majority of circulating haemocytes in M-line B. glabrata are fully-spread granulocytes, which increase significantly in number in snails following exposure to A. cantonensis larvae. However, populations of partially-spread granulocytes, round cells, hyalinocytes and miscellaneous haemocytes were relatively constant. The size of capsules around the parasite increased during the 42-day interval of the experiment. The haematopoietic organ increased in size in response to infection. 相似文献
26.
In normal rats, before Day 12 of pseudopregnancy, minimal levels of 20 alpha-HSD activity were detected in functional CL whereas those in the residue were 3-5 times higher. When ovulation was blocked for more than 2 weeks by placing rats in a continuously lit environment before the induction of pseudopregnancy, only minimal levels of 20 alpha-HSD activity were detectable in the functional CL and residue before Day 12. In normal pseudopregnant rats, there was a linear increase in 20 alpha-HSD activity from Day 12 to 15 in the functional CL and residue, but the rate of elevation was much higher in functional CL. This tendency was much more clear-cut in rats in the continuous lighting. In immature rats in which pseudopregnancy was induced by PMSG and hCG treatment, 20 alpha-HSD activity peaked twice. The first small peak was attributed to the early regression of some of the large number of corpora lutea, and the changes in 20 alpha-HSD activity in most of the corpora lutea paralleled those in rats in continuous lighting. Bromocriptine abolished the prolactin surges, and in normal pseudopregnant rats an increase in 20 alpha-HSD activity in functional CL started from 12 h and the rate of the increase was accelerated from 36 h afterwards, while a relatively small increase was observed in the residue at 18 h and later.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
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Previously, we observed sequential two-step alteration, growth stimulation, and progression to a more malignant state in NIH 3T3 cells transfected by human papillomavirus type 16 (HPV-16) DNA. In this study, we prepared a cDNA library from RNA extracted from cells transfected with the HPV-16 DNA and isolated cDNA clones which had growth-stimulating activity. Analysis of these cDNA clones indicated that the E7 open reading frame alone is responsible for inducing both steps of this cell transformation. 相似文献
29.
This study was carried out in order to exclude the possibility that streptozotocin (STZ) as such may be directly responsible for the alteration in the metabolism of bile acids. The STZ-diabetic rats had a higher percentage of cholic acid and a lower percentage of chenodeoxycholic acid and beta-muricholic acid compared to the controls. Although the rats were given STZ, yet there was no alteration in the bile acid pattern when they were protected against diabetes by simultaneous administration of nicotinamide. Nicotinamide itself had no influence on the composition of bile acids. Treatment of the STZ-diabetic rats with insulin cancelled the altered composition of bile acids partially. From these results it became clear that the alteration of the bile-acid metabolism in the STZ-treated rats was caused not by a direct effect of STZ itself but by an absolutely or relatively insulin-deficient state induced by STZ. 相似文献
30.
The potential causes of the variable nature of recruitment of marine organisms can be inferred from the scales over which they vary. Sampling for recruits of Semibalanus cariosus on the intertidal concrete tetrapods at 21 fishing ports along the Kameda Peninsula, southern Hokkaido, Japan, was conducted at the end of the recruitment season in 1994 at three spatial scales: at each fishing port, separated by several km; at two sites at each fishing port, separated by several hundred m; and on three blocks at each site, separated by 1–2 m. At all spatial scales, recruitment intensity was independent of adult densities. Recruitment densities significantly varied within all spatial-scales, however, 85.6% of the total variances was estimated to be due to variation among ports. Such km-scale variation of recruitment intensities coincided with the hydrographic pattern of the direction of coastal current. 相似文献