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41.
42.
Evidence by cellular mosaicism for monoclonal metastasis of spontaneous mouse mammary tumors 总被引:2,自引:0,他引:2
Female (SHN X C3H/He)F1 mice carrying spontaneous mammary tumors with cellular mosaicism with respect to isozymes of phosphoglycerate kinase (PGK) showed a high incidence of lung metastases. On resection of successively appearing mammary tumors, mice survived a maximum of 8 tumors. In these mice with multiple primary mammary tumors and multiple metastases, not only each individual metastasis but also all the metastases in the same lung had the same pattern of PGK isozymes and the same histologic type in the PGK-mosaic background of the host, indicating the monoclonal origin of these metastases. In several cases, this single pattern of metastatic colonies coincided with that of only one of several primary tumors, indicating that this tumor had metastasized. In these cases, these tumors were not necessarily the earliest of the primary tumors, and they were not located in any particular site. 相似文献
43.
H Tsukuma A Oshima T Hiyama I Fujimoto H Yamano M Tanaka 《International journal of epidemiology》1987,16(4):579-583
In order to examine time trends of the prevalences of HBeAg positives among HBV carriers in Japan, we analysed data on HBeAg of HBsAg positive voluntary blood donors (23,560 males, and 8659 females) at the Osaka Red Cross Blood Centre between January 1977 and March 1984. Age-specific prevalences of HBeAg positives decreased year by year for both sexes, especially for those in their teens and twenties. The prevalences of HBeAg positives decreased with age, but at any given age it was lower for the later than for the earlier birth cohorts. Although reasons for the secular declines are unknown, the findings suggest that the prevalence of HBeAg positives among HBV carriers will continue to decrease in Japan. This, together with the immunization programme implemented this year, may lead to a future reduction in the risk of HBV related liver diseases in Japan. 相似文献
44.
K Tanaka Y Miyake S Sasaki Y Ohya S Miyamoto I Matsunaga T Yoshida Y Hirota H Oda 《Magnesium research》2006,19(4):268-275
There have only been a few studies on the role of mineral intake in tooth loss. We investigated the association between mineral intake and the prevalence of tooth loss in Japan. We used the baseline data on 1002 pregnant women who were enrolled in the Osaka Maternal and Child Health Study between November 2001 and March 2003. Tooth loss was defined as the previous extraction of one or more teeth. Nutrient intake was assessed by a validated diet history questionnaire. Prevalence odds ratios and confidence intervals were estimated by applying a multiple logistic regression model. The adjusted odds ratio upon comparison of the highest quartile with the lowest quartile of magnesium intake was 0.64 (95% confidence interval, 0.42-0.99), showing a tendency for an inverse dose-response relationship (p for linear trend = 0.05). There were no associations between the level of consumption of calcium, phosphate, iron, zinc, or copper and tooth loss. The present findings suggest that intake of magnesium is related to reduced prevalence of tooth loss among young Japanese women. 相似文献
45.
46.
47.
Tarek A. Amer Tarek F. Elwakil Mahmoud S. Elbasiouny 《European journal of plastic surgery》2007,30(2):67-73
Haemangiomas are the most common tumours of infancy. They typically proliferate then involute with considerable variation
as regards to their rates of proliferation and involution. Haemangioma of the nasal tip is a lesion of special characteristics.
During proliferation, it expands, contracts and deviates the nasal cartilages. Particularly, it regresses slowly and frequently
involutes incompletely. That is why excision of the lesion is frequently suggested. The present study was conducted to evaluate
open rhinoplasty after initial non-excision treatment modalities namely, intra-lesional corticosteroid injections and laser
treatment, as a protocol of treatment for nasal tip haemangiomas. Twelve patients with nasal tip haemangiomas were included
in the present study. Patients of both sexes, of different ages, with deep and mixed haemangiomas were studied. Disfigurement
was the constant presenting symptom. Initial non-excision treatment reported different responses as denoted by the regression
of the lesions’ size. Haemangiomas constantly extended between the medial crura of the alar cartilages as noted by the constant
widening of the columella pre-operatively and the obvious separation of the nasal cartilages intra-operatively. This separation
was constantly found to require approximation by sutures. The results of the present study concluded that whenever an early
presentation with nasal tip haemangioma could be established, initial non-excision treatment followed by open rhinoplasty
could be a useful protocol of treatment. Within the limitations of the present study, this protocol could achieve an early,
safe and effective treatment for nasal tip haemangiomas with provisionally acceptable cosmetic outcomes so far. 相似文献
48.
This study investigates whether tissue recoil or patient intrinsic factors influence the final position of the nipple areola
complex (NAC) after reduction mammoplasty.
The age, pre-operative ptosis, BMI and weight of the tissue resected were recorded as patient intrinsic factors in 37 patients
undergoing reduction mammoplasty. The “spring-back” value was defined as the distance from the sternal notch to a nipple landmark
on the breast meridian with the patient sitting up, minus the same measurement repeated with the patient recumbent to eliminate
the pull of gravity on the breast. Spring back was measured pre-operatively for the nipple and nipple mark then post-operative
for the nipple. The difference in centimeters between the final post-operative distance from the sternal notch to the nipple
and the level intended by the pre-operative nipple mark was termed the “judgment error.” The final position of the post-operative
nipple and the judgment error was compared to the spring-back values and patient intrinsic factors.
Pre-operative ptosis was statistically related to increasing patient BMI and mass of tissue resected per breast. Pre-operative
spring-back values for the nipple increased with increasing ptosis, BMI and decreasing age. Spring-back values were greater
in the lower pole of the breast than in the upper pole. The final position of the nipple was higher than the pre-operative
mark in 65% of cases, lower in 8% and as marked in 27% of cases. The post-operative NAC was, on average, 0.6 cm higher than
planned pre-operatively. The post-operative distance from the sternal notch to the nipple increased with increasing pre-operative
ptosis, mass of breast tissue resected per breast and all three spring-back values. The difference between the level of the
pre-operative mark and the final nipple position showed a weak correlation with post-operative spring-back values.
The parameters of ptosis, BMI, weight of tissue resected per breast and pre-operative nipple spring back reflect body habitus
and breast size. Spring-back values vary between the upper and lower pole of the breast. The final NAC position was higher
than that intended at pre-operative marking in the majority of cases. The surgeon instinctively marks the nipple lower in
patients with greater pre-operative ptosis and in whom a larger resection is anticipated. Judgment error did not relate to
intrinsic factors nor to pre-operative spring-back values; hence, these parameters cannot be applied as predictive tools for
more accurate pre-operative marking of the nipple position. This study suggests that the pre-operative nipple mark should
be placed, with the patient sitting up, at least 23 cm from the sternal notch and 0.6 cm lower than the final position estimated
using the inframammary crease as a landmark.
An invited commentary on this paper is available at . 相似文献
49.
50.
Jamshid Shirani Jagat Narula William C. Eckelman Navneet Narula Vasken Dilsizian 《Journal of nuclear cardiology》2007,14(1):100-110
Conclusions Noninvasive imaging of neurohumoral upregulation in remodeled myocardium suggests that an imaging strategy can be developed
for predicting the rate of remodeling and likelihood of HF development. This should allow a more judicious use of neurohumoral
antagonists especially in subjects who do not have manifest HF.74 In others specific targeted imaging may allow timely selection of individualized treatment strategies and ensure optimization
of therapeutic intervention. Similar to ACE and AII receptors, multiple other targets in the hormonal cascades can identify
the likelihood of adverse and favorable remodeling.74 相似文献