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排序方式: 共有2315条查询结果,搜索用时 341 毫秒
1.
Anastasiia Panfilova Sarah E. Shelton Cristina Caresio Ruud J.G. van Sloun Filippo Molinari Hessel Wijkstra Paul A. Dayton Massimo Mischi 《Ultrasound in medicine & biology》2019,45(2):539-548
Dynamic contrast-enhanced ultrasound (DCE-US) has been proposed as a powerful tool for cancer diagnosis by estimation of perfusion and dispersion parameters reflecting angiogenic vascular changes. This work was aimed at identifying which vascular features are reflected by the estimated perfusion and dispersion parameters through comparison with acoustic angiography (AA). AA is a high-resolution technique that allows quantification of vascular morphology. Three-dimensional AA and 2-D DCE-US bolus acquisitions were used to monitor the growth of fibrosarcoma tumors in nine rats. AA-derived vascular properties were analyzed along with DCE-US perfusion and dispersion to investigate the differences between tumor and control and their evolution in time. AA-derived microvascular density and DCE-US perfusion exhibited good agreement, confirmed by their spatial distributions. No vascular feature was correlated with dispersion. Yet, dispersion provided better cancer classification than perfusion. We therefore hypothesize that dispersion characterizes vessels that are smaller than those visible with AA. 相似文献
2.
Diede L. Loopik Renée M. Ebisch Joanna IntHout Willem J. Melchers Leon F. Massuger Ruud L. Bekkers Albert G. Siebers 《International journal of cancer. Journal international du cancer》2020,147(3):897-900
Women with cervical intraepithelial neoplasia grade 3 (CIN3) have a long-lasting increased risk for noncervical high-risk human papillomavirus (hrHPV)-related (pre)malignancies. The aim of our study was to estimate this risk in women with recurrent CIN3 compared to women without a history of CIN3 and women with a single episode of CIN3. Women with a CIN3 diagnosis between 1990 and 2010 were obtained from the Dutch Pathology Registry (PALGA) and matched with a control group of women without CIN3. Analysis has been conducted in a subset of women with recurrent CIN3, defined as reoccurrence minimally 2 years post-treatment. Cases of noncervical hrHPV-related (pre)malignancies of the anus, vulva, vagina and oropharynx were identified until 2015 and incidence rate ratios (IRRs) were estimated. Then, 1,797 women with recurrent CIN3 were included with a median age of 34 years (range 18–76) and 31,594 person-years of follow-up. Women with recurrent CIN3 had an increased risk of developing noncervical hrHPV-related (pre)malignancies compared to women without CIN3 with an IRR of 25.96 (95%CI 6.32–106.58). The IRR was 2.48 (95% CI 1.87–3.30) compared to women with a single episode of CIN3. Studies on posttreatment follow-up and prophylactic hrHPV vaccination are warranted. 相似文献
3.
Henk R Franke F Froukje Snaaijer Paul W H Houben Marius J van der Mooren 《Gynecological endocrinology》2006,22(12):692-697
OBJECTIVE: To assess the effects of adding combined estradiol/norethisterone acetate therapy (CENT) to goserelin acetate treatment (GA) of dysfunctional uterine bleeding (DUB) in perimenopausal women. METHODS: In a randomized, placebo-controlled, double-blind trial followed by an open follow-up study, 31 perimenopausal women with DUB were recruited from gynecological outpatient departments of two Dutch hospitals and randomized for treatment with either GA/placebo or GA/CENT for 6 months followed by 18 months of GA/CENT for all. The main outcome measures were abdominal pain, number of bleeding days, double-layer endometrial thickness (DET), Greene climacteric score (GCS), visual analog scale for well-being, bone mineral density (BMD) and mammographic density (BI-RAD score). RESULTS: Abdominal pain, number of bleeding days and DET decreased in both groups, the between-group difference in decrease not being statistically significant. GCS initially showed significant improvement in the GA/CENT group. BMD decreased significantly in the GA/placebo group (-4.1%) compared with the GA/CENT group (-0.3%). Another 18 months of GA/CENT did not result in a lasting difference in BMD between groups. BI-RAD scores did not differ significantly between or within the two groups. CONCLUSIONS: Adding CENT to GA treatment for DUB in perimenopausal women initially prevented BMD loss and improved climacteric complaints, while having no negative impact on vaginal bleeding, abdominal pain or BI-RAD scores. However, prolonged treatment did not result in a lasting prevention of bone loss. 相似文献
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Boudewijn J. M. Braakhuis C. René Leemans Ruud H. Brakenhoff 《Journal of oral pathology & medicine》2004,33(6):317-322
Based on recent genetic studies, we propose a progression model for the development of oral squamous cell carcinoma. In the initial phase, a stem cell acquires a genetic alteration; subsequently a patch is formed, a clonal unit consisting of the stem cell with its daughter cells that all share the DNA alteration. The next critical step is the conversion of a patch into an expanding field as a result of additional genetic alterations. This mucosal field replaces the normal epithelium and in the oral cavity such fields have been detected with dimensions of over 7 cm in diameter. Sometimes these fields are visible as leukoplakia. Ultimately, clonal selection leads to the development of carcinoma within this contiguous field of pre-neoplastic cells. An important clinical implication of this model is that fields often remain after surgery of the primary tumor and may lead to new cancers, presently designated by clinicians as second primary tumors or local recurrences. 相似文献
8.
Effects of androgens and estrogens on the vasopressin and oxytocin innervation of the adult rat brain 总被引:5,自引:0,他引:5
Geert J. De Vries Wouter Duetz Ruud M. Buijs Joop van Heerikhuize Jan T.M. Vreeburg 《Brain research》1986,399(2):296-302
Recently we reported that castration of rats eliminates vasopressin immunoreactivity in the lateral septum and other areas that appear to receive vasopressin innervation from the bed nucleus of the stria terminalis. Testosterone treatment counteracts this effect of castration. In the present study, we investigated whether this action of testosterone depends on its androgenic or estrogenic metabolites by treating long-term castrated rats with estradiol (E) and/or 5 alpha-dihydrotestosterone (DHT) or testosterone. The brains were then processed for immunocytochemistry or radioimmunoassay. DHT did not increase vasopressin staining in the lateral septum, although it fully restored the size of the seminal vesicles. E did restore the original fiber density, but individual fibers stained more weakly than in sham-operated males. Only treatment with both E and DHT fully restored the vasopressin innervation. This pattern was also reflected in the radioimmunoassay data. The vasopressin content of the lateral septum decreased about 90% after castration but was fully restored by either testosterone or E + DHT treatment. E alone, however, was only half as effective as E + DHT. The treatments had no effect on the oxytocin content of the septum, or on the vasopressin or oxytocin content of the dorsal vagal complex. The results suggest that E mediates most of the effects of testosterone on the vasopressin innervation of the lateral septum. DHT enhances the response to E but has little effect on its own. 相似文献
9.
Johannes Irsch Rudolf Hendriks Hans Tesch Ruud Schuurman Andreas Radbruch 《European journal of immunology》1993,23(2):481-486
In activated murine B lymphocytes, immunoglobulin class switch recombination occurs as a highly regulated process which is targeted to distinct switch regions. Here we present first evidence that in human B lymphocytes, switch recombination is targeted to distinct switch regions as well. In a panel of clonally unrelated IgG1-expressing human B cells, immortalized by Epstein-Barr virus (EBV) transformation, seven out of nine cells show switch recombination between Sμ and Sγ1 on both alleles, the active and inactive one. The remaining cells show no switch recombination on the inactive IgH locus. The very strong correlation of switch recombination on both alleles of IgG1-expressing cells proves that class switch recombination to IgG1 is not random but directed in human B lymphocytes. 相似文献
10.
Bradford L. Kirkman-Liff Ruud Lapre Tracy L. Kirkman-Liff 《The International journal of health planning and management》1988,3(2):89-109
The United States and the Netherlands are the focus for this comparative analysis of the evolutionary interaction between health planning and the political system, seen in the context of change in social and economic ideologies. While health planning in the USA started in 1946, it was the comprehensive health planning program in 1966 that created the form to be followed by Health Systems Agency effort in 1974: local, voluntary planning, coordinated by state agencies, supported by federal funding. Health planning in the Netherlands has moved through four distinct periods: a hospital construction period, starting during the post-war recovery; a hospital regionalization period, from 1971 through the late 1970s; a transition period from the late 1970s to 1982, during which several planning approaches were considered; and, the current comprehensive health and social services planning period. Today, federal support for health planning in the US has been eliminated as part of the current de-regulatory, competitive health care strategy. Health planning in the US is now an institutional activity, with less focus on community needs. Advocated changes in the Dutch planning approach incorporate ideas similar to past approaches in the US; but, a failed approach in one nation may work in another, if the underlying cultural and organizational characteristics are sufficiently different. 相似文献