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71.
Interferon-alpha (IFN-alpha) has proved effective in the treatment of hemangiomas, hemangioblastomas, and Kaposi's sarcoma. To investigate the ability of IFNs to inhibit angiosarcoma, we used two transformed murine endothelial cell lines that form angiosarcomas in vivo. SVR and MS1-VEGF cell lines express oncogenic H-ras or vascular endothelial growth factor (VEGF), respectively. IFN-alpha1,8, which is active against murine and human cells, inhibited SVR and MS1-VEGF proliferation in vitro by 40% at 10(3) U/mL (p = 0.028). In vivo, IFN-alpha1,8 inhibited SVR tumor volume by 71% (p = 0.047) and MS1-VEGF volume by 79% (p = 0.003). Tumor-induced angiogenesis was decreased in SVR tumors by 52% (p = 0.005) and in MS1-VEGF tumors by 58% (p = 0.001). Sera from IFN-alpha1,8-treated mice bearing either SVR or MS1-VEGF tumors demonstrated a 5-fold increase in IP-10/CXCL10 (p = 0.001), an IFN-induced antiangiogenic protein. Both recombinant IP-10 and IFN-alpha1,8 inhibited human umbilical vein endothelial cell (HUVEC) vessel formation in the fibrin gel assay, a three-dimensional culture model of angiogenesis, by 56% at 25 ng/mL and 50% at 1.2 ng/mL, respectively (p < 0.001). An IP-10 blocking antibody restored vessel formation to 80% of untreated controls (p = 0.001). Given the magnitude of the in vivo response, these data suggested that the antitumor effects of IFN-alpha1,8 were likely mediated through angiogenesis inhibition rather than solely by direct inhibition of tumor cell proliferation.  相似文献   
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OBJECTIVES: To determine whether aromatase expression in the eutopic endometrium and adenomyotic foci is affected by previous use of oral contraceptives containing gestodene, and to determine whether changes in cyclooxygenase-2 (COX-2) expression occur in adenomyosis during the menstrual cycle. PATIENT AND METHODS: This was a retrospective cohort study carried out in paraffin-embedded endometrial tissue obtained from patients with a histological diagnosis of adenomyosis obtained during the proliferative (n = 25) and luteal (n = 10) phases of the menstrual cycle and following the use of continuous oral contraception with gestodene/ethinyl estradiol (n = 7). COX-2 and aromatase expression were measured in both eutopic endometrium and adenomyotic foci using immunohistochemical methods. RESULTS: Aromatase expression was detected in 80% of the endometrial slices by immunohistochemistry. In positive cases, aromatase was mainly detected in the stromal cells of the eutopic endometrium, whereas in the adenomyotic foci this expression was negative in the majority of the cases. Oral contraceptives containing gestodene, on the other hand, were effective in suppressing aromatase expression in both eutopic and ectopic endometrium. COX-2 expression was detected by immunohistochemistry in the glandular epithelium of both eutopic endometrium and adenomyotic foci and there were no significant changes in its intensity throughout the menstrual cycle. CONCLUSION: Aromatase expression in the eutopic endometrium and adenomyotic foci is suppressed by oral contraceptives containing gestodene. Increased aromatase activity may be responsible for the persistent COX-2 expression during the luteal phase.  相似文献   
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PURPOSE: Concern over stigma as a consequence of genetic testing has grown in response to the recent increase in genetic research and testing resulting from the Human Genome Project. However, whether a genetic or hereditary basis necessarily confers a stigma to a condition remains unexamined. METHODS: We performed a qualitative interview study with 86 individuals with one of four conditions: deafness or hearing loss, breast cancer, sickle cell disease, and cystic fibrosis. The first two groups were divided approximately between people who ascribed their conditions to a genetic or hereditary cause and those who did not. RESULTS: Respondents interpreted genetic or hereditary causes and nongenetic causes in a variety of ways. Subjects with breast cancer reported the most consistently negative interpretation of genetic cause. This response concerned future ill health, not an enduring sense of stigma. Deaf and hard of hearing subjects provided the most consistently positive comments about a genetic or hereditary basis to their condition, casting familial hearing loss as a vital component of group and individual identity. Respondents with sickle cell disease and cystic fibrosis offered similar and positive interpretations of the genetic cause of their condition insofar as it meant their conditions were not contagious. CONCLUSIONS: Although some subjects report feeling stigmatized as a result of their condition, this stigmatization is not uniformly associated with the condition's cause, genetic or otherwise. Instead, stigma emerges from a variety of sources in the context of the lived experience of a particular condition.  相似文献   
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BACKGROUND: Arterial hypertension and postmenopausal reduction of estrogen levels may be involved in modifications of the stiffness of large arteries. OBJECTIVES: To evaluate the pulse-wave velocity (PWV) and indirectly the arterial stiffness in hypertensive postmenopausal women submitted to hormone therapy with estradiol alone or combined with norethisterone acetate. SUBJECTS: Forty-five hypertensive postmenopausal women were double-blindly, randomly assigned to three arms of treatment: placebo (group I); estradiol 2 mg/day (group II); or estradiol 2 mg/day and norethisterone acetate 1 mg/day (group III). METHODS: Arterial stiffness was assessed from PWV measurements of the common carotid and femoral arteries (CF-PWV) and the common carotid and radial arteries (CR-PWV) obtained using the automatic Complior(R) device, taken at baseline and after 12 weeks of treatment. RESULTS: After the 12-week treatment, values of CF-PWV and CR-PWV were not significantly different (p = 0.910 and p = 0.736, respectively) among the groups. Systolic blood pressure showed a positive correlation with CF-PWV in groups II and III (p = 0.02 and p < 0.001, respectively). CONCLUSIONS: PWV and arterial stiffness in postmenopausal hypertensive women did not reduce over a 12-week treatment with estradiol alone compared with the same period of treatment with estradiol combined with norethisterone acetate.  相似文献   
76.
The aim of our study was to determine the incidence, timing, and severity of vaginal stenosis in patients with carcinoma of the cervix who had received pelvic and/or vaginal radiotherapy as part of their treatment. We also sought to determine if there were any predisposing factors for the development of stenosis. A retrospective chart review was undertaken for all the patients diagnosed with carcinoma of the cervix between January 1, 1990, and December 31, 2000 and treated with pelvic and/or vaginal radiation at Westmead Hospital. Since January 1, 1990, data regarding vaginal stenosis has been prospectively recorded on all the patients. Data collected included patient demographics, stage of disease, treatments administered, and incidence, timing, and severity of vaginal stenosis. One hundred and eighty-eight patients were treated. Mean age was 58.6 years. Thirteen percent of patients had stage IB disease, 45% had stage II disease, 39.5% had stage III disease, and 1.5% had stage IV disease. One hundred and seventy-nine patients returned for follow-up, and data regarding vaginal toxicity were available in 98%. Twenty-seven percent had grade 1 toxicity (partial stenosis or shortening but not complete occlusion), and 11% had grade 2 (complete occlusion). Stenosis of any grade was noted at a mean of 9.6 months and median of 7.5 months (range, 26 days-5.6 years) from completion of treatment. The only prognostic factor associated with increased risk of stenosis was age greater than 50 years (odds ratio 2.26). Vaginal stenosis is a common complication of pelvic and vaginal radiotherapy, occurring in 38% of patients. Stenosis occurs most often in the first year after treatment. Patients over the age of 50 are most at risk.  相似文献   
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In einer clusteranalytischen Untersuchung mit 137 Patienten, die einen Parasuizid verübt hatten, wurden 6 Subgruppen unter Berücksichtigung der Klassifikationsvariable “suicide intent” isoliert. Es wurde die Hypothese geprüft, dass sich sowohl die Motivstrukturen als auch die Raten an wiederholten Parasuiziden in Abh?ngigkeit der Clusterl?sung bedeutsam voneinander unterscheiden. Die Ergebnisse unterstützen die Annahme einer zunehmenden Ausdifferenzierung der interpersonell orientierten Motivstrukturen mit sinkendem bzw. einer Einengung der Motivstruktur auf den Todeswunsch mit steigendem “suicide intent”. Es wurden folgende Subgruppen differenziert: eine Suizid-Hochrisikogruppe mit ausschlie?licher Todesintention und -motivation, 2 moderate Suizid-Risikogruppen mit hoher Todesintention und leichten Tendenzen zu interpersoneller Motivation, eine Subgruppe, gekennzeichnet durch eine manipulativ/strategisch orientierte Motivstruktur und auff?llig h?ufigen Parasuizidwiederholungen, eine Subgruppe mit vorrangig appellativ orientierten Motiven, Kontrollverlust und vergleichsweise seltenen Parasuizidwiederholungen und eine Subgruppe mit ambivalenter Motivstruktur (interpersonell und todesorientiert).  相似文献   
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