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排序方式: 共有1346条查询结果,搜索用时 15 毫秒
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Hedelin M Bälter KA Chang ET Bellocco R Klint A Johansson JE Wiklund F Thellenberg-Karlsson C Adami HO Grönberg H 《The Prostate》2006,66(14):1512-1520
BACKGROUND: The causes of prostate cancer are poorly understood, but genetic factors may be more important than for many other malignancies, and dietary phytoestrogens may be protective. Because phytoestrogens bind tightly to the estrogen receptor-beta, we conducted an epidemiologic investigation of synergistic effects between phytoestrogen intake and estrogen receptor-beta gene polymorphisms. METHODS: We performed a population-based case-control study in Sweden. All participants reported their phytoestrogen intake and donated a blood sample. We identified four haplotype-tagging single nucleotide polymorphisms (htSNPs) and genotyped these htSNPs in 1314 prostate cancer patients and 782 controls. Odds ratios were estimated by multivariate logistic regression. Interactions between phytoestrogen intake and estrogen receptor-beta SNPs on prostate cancer risk were evaluated considering both multiplicative and additive effect scales. RESULTS: We found a significant multiplicative interaction (P = 0.04) between dietary intake of phytoestrogens and a promoter SNP in the estrogen receptor-beta gene (rs 2987983-13950), but not with any of the three other htSNPs (P = 0.11, 0.69, 0.85). Among carriers of the variant promoter alleles, we found strong inverse associations with increasing intake of total phytoestrogens (odds ratio for highest vs. lowest quartile = 0.43; P for trend <0.001), isoflavonoids (odds ratio = 0.63; P for trend = 0.05), and coumestrol (odds ratio = 0.57; P for trend = 0.003). We found no association between phytoestrogens and prostate cancer among carriers homozygous for the wild-type allele (TT). CONCLUSIONS: Our study provides strong evidence that high intake of phytoestrogens substantially reduce prostate cancer risk among men with specific polymorphic variation in the promoter region of the estrogen receptor-beta gene. 相似文献
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Rafferty MA Goldstein DP Rotstein L Asa SL Panzarella T Gullane P Gilbert RW Brown DH Irish JC 《Journal of the American College of Surgeons》2007,205(4):602-607
BACKGROUND: This study compared our experience with completion thyroidectomy (CT) and total thyroidectomy (TT) in the management of well-differentiated thyroid cancer (WDTC). We compared complication rates and analyzed the implications of the intraoperative management of the parathyroid glands. STUDY DESIGN: We performed a retrospective cohort study comparing outcomes between patients undergoing CT and TT between January 1994 and December 2004. All patients had surgery for either suspected or confirmed WDTC on fine-needle aspiration. RESULTS: There were 201 CTs and 149 TTs. Mean hospital stays were 4.5 and 3.5 days for the CT and TT groups, respectively (p=0.001). Temporary recurrent laryngeal nerve paresis occurred in 2.0% (4 of 201) and 3.3% (5 of 149) of patients in the CT and TT groups, respectively. There was one (0.5%) case of permanent recurrent laryngeal nerve paralysis in the CT group. Permanent hypoparathyroidism rates were 2.5% and 3.3% in the CT and TT groups, respectively. There was no difference between the two groups in terms of total numbers of parathyroid glands autotransplanted (p=0.63) or present in the specimen (p=0.26). CONCLUSIONS: Completion thyroidectomy is a safe and appropriate option in the management of select cases of WDTC in which a definitive preoperative or intraoperative diagnosis is not available. But it requires a longer hospitalization, so it has implications for both hospital resources and the patients involved. 相似文献
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The effects of somatostatin or the somatostatin analog SMS 201–995 were studied on 4 densely granulated somatotroph adenomas
and 4 sparsely granulated somatotroph adenomas in vitro. Release of growth hormone (GH) into culture media during incubation
with somatostatin or SMS 201 -995 were measured by radioimmunoassay, and light-microscopical and ultrastructural morphometric
parameters were compared with those of cultured control somatotroph adenoma cells of the same tumor. In all tumors except
for 1 densely granulated somatotroph adenoma, somatostatin or SMS 201–995 decreased GH release into culture media in 24- and
2-hour incubations. After 48-hour incubation with somatostatin or SMS 201–995, there was no change in cell size or secretory
granule diameter. One densely granulated adenoma showed decreased cytoplasmic volume density (CVD) of Golgi apparatus and
secretory granules, and a sparsely granulated adenoma had reduced CVD of endoplasmic reticulum. All the tumors that responded
with decreased GH release exhibited increased CVD of lysosomes after incubation with somatostatin or SMS 201–995. These results
indicate that both densely and sparsely granulated somatotroph adenomas respond to somatostatin inhibition and, furthermore,
that inhibition of hormone release is associated with accumulation of lysosomes, suggesting lysosomal degradation of stored
hormone.
Hospital 20 Nov. (ISSSTE) Coyoacan y Felix Cuevas, Colonia del Valle and (Dept Patologia) y Hospital de Especialidades (C.M.N.,
IMSS) Cuauhtemoc y Dr. Marquez, Mexico City (IF). 相似文献
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Davies Adeloye Eyitayo O. Owolabi Dike B. Ojji Asa Auta Mary T. Dewan Timothy O. Olanrewaju Okechukwu S. Ogah Chiamaka Omoyele Nnenna Ezeigwe Rex G. Mpazanje Muktar A. Gadanya Emmanuel Agogo Wondimagegnehu Alemu Akindele O. Adebiyi Michael O. Harhay 《Journal of clinical hypertension (Greenwich, Conn.)》2021,23(5):963
Improved understanding of the current burden of hypertension, including awareness, treatment, and control, is needed to guide relevant preventative measures in Nigeria. A systematic search of studies on the epidemiology of hypertension in Nigeria, published on or after January 1990, was conducted. The authors employed random‐effects meta‐analysis on extracted crude hypertension prevalence, and awareness, treatment, and control rates. Using a meta‐regression model, overall hypertension cases in Nigeria in 1995 and 2020 were estimated. Fifty‐three studies (n = 78 949) met our selection criteria. Estimated crude prevalence of pre‐hypertension (120‐139/80‐89 mmHg) in Nigeria was 30.9% (95% confidence interval [CI]: 22.0%‐39.7%), and the crude prevalence of hypertension (≥140/90 mmHg) was 30.6% (95% CI: 27.3%‐34.0%). When adjusted for age, study period, and sample, absolute cases of hypertension increased by 540% among individuals aged ≥20 years from approximately 4.3 million individuals in 1995 (age‐adjusted prevalence 8.6%, 95% CI: 6.5‐10.7) to 27.5 million individuals with hypertension in 2020 (age‐adjusted prevalence 32.5%, 95% CI: 29.8‐35.3). The age‐adjusted prevalence was only significantly higher among men in 1995, with the gap between both sexes considerably narrowed in 2020. Only 29.0% of cases (95% CI: 19.7‐38.3) were aware of their hypertension, 12.0% (95% CI: 2.7‐21.2) were on treatment, and 2.8% (95% CI: 0.1‐5.7) had at‐goal blood pressure in 2020. Our study suggests that hypertension prevalence has substantially increased in Nigeria over the last two decades. Although more persons are aware of their hypertension status, clinical treatment and control rates, however, remain low. These estimates are relevant for clinical care, population, and policy response in Nigeria and across Africa. 相似文献
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Relationship between the expression of various markers and prognostic factors in breast cancer 总被引:5,自引:0,他引:5
Anim JT John B Abdulsathar S SA Prasad A Saji T Akhtar N Ali V Al-Saleh M 《Acta histochemica》2005,107(2):87-93
The immunohistochemical detection of six markers of breast cancer has been compared in the present study with known prognostic factors of the disease to establish locally a standard panel of markers for the management of breast cancer. Sections of tissue of 114 consecutive breast cancer cases were studied immunohistochemically, using antibodies against oestrogen receptor (ER), progesterone receptor (PR), androgen receptor, c-erbB2, cathepsin D, and cyclin D. Marker labelling was graded as recommended in the literature. Using the chi(2)-test, relationships were determined between marker labelling and histological type of cancer, tumour grade, tumour size, axillary lymph node status and age of patient. A p value below 0.05 was considered significant. A positive relationship was found between ER and PR and lower grades of cancer, and a negative relationship was found with medullary and atypical medullary carcinoma. The four other markers showed no relationship with grade or type of cancer. All markers showed no significant relationship with size of tumour, presence of axillary node metastasis or age of patient. There was positive correlation between c-erbB2 and cathepsin D. Our study confirms the association between ER and PR and histological type and grade of breast cancer, both known parameters of good prognosis. We found no consistent relationship between the other four markers and prognostic factors studied, other than the suggestion that c-erbB2 and cathepsin D may be useful markers for poor prognosis and can be usefully applied locally, especially in the light of the current availability of trastuzumab (Herceptin) for management of c-erbB2-positive cases. We found no relationship between the markers and tumour size, axillary lymph node status or age. 相似文献