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61.
Previous studies have shown that obesity and hypertension are associated with increased risk of renal cell carcinoma (RCC), but less is known about the association to other metabolic factors. In the Metabolic Syndrome and Cancer project (Me-Can) data on body mass index (BMI, kg/m2), blood pressure, and circulating levels of glucose, cholesterol, and triglycerides were collected from 560,388 men and women in cohorts from Norway, Austria, and Sweden. By use of Cox proportional hazard models, hazard ratios (HR) were calculated for separate and composite metabolic exposures. During a median follow-up of 10 years, 592 men and 263 women were diagnosed with RCC. Among men, we found an increased risk of RCC for BMI, highest vs. lowest quintile, (HR = 1.51, 95% CI 1.13–2.03), systolic blood pressure, (HR = 3.40, 95% CI 1.91–6.06), diastolic blood pressure, (HR = 3.33, 95% CI 1.85–5.99), glucose, (HR = 3.75, 95% CI 1.46–9.68), triglycerides, (HR = 1.79, 95% CI 1.00–3.21) and a composite score of these metabolic factors, (HR = 2.68, 95% CI 1.75–4.11). Among women we found an increased risk of RCC for BMI, highest vs. lowest quintile, (HR = 2.21, 95% CI 1.32–3.70) and the composite score, (HR = 2.29, 95% CI 1.12–4.68). High levels of the composite score were also associated with risk of death from RCC among both men and women. No multiplicative statistical or biological interactions between metabolic factors on risk of RCC were found. High levels of BMI, blood pressure, glucose and triglycerides among men and high BMI among women were associated with increased risk of RCC.  相似文献   
62.
Recent clinical studies have shown that inorganic arsenic trioxide (As(2)O(3)) at low concentrations induces complete remission with minimal toxicity in patients with refractory acute promyelocytic leukemia (APL). Preclinical studies suggest that As(2)O(3) induces apoptosis and possibly differentiation in APL cells. Like APL cells, neuroblastoma (NB) cells are thought to be arrested at an early stage of differentiation, and cells of highly malignant tumors fail to undergo spontaneous maturation. Both APL and NB cells can respond with differentiation to retinoic acid (RA) treatment in vitro and probably also in vivo. For that reason we investigated the effect of As(2)O(3) alone and in combination with RA on NB cell lines. In vitro, the number of viable NB cells was reduced at As(2)O(3) concentrations around 1 microM after 72 h exposure. The IC50 in six different cell lines treated for 3 days was in the 1.5 to 5 microM concentration interval, the most sensitive being SK-N-BE(2) cells derived from a chemotherapy resistant tumor. The combined treatment with RA (1 and 3 microM) showed no consistent additional effect with regard to induced cell death. The effect of As(2)O(3) on NB cell number involved As(2)O(3)-induced apoptotic pathways (decreased expression of Bcl-2 and stimulation of caspase-3 activity) with no clear evidence of induced differentiation. The in vivo effect of As(2)O(3) on NB growth was also investigated in nude mice bearing tumors of xenografted NB cells. Although tumor growth was reduced by As(2)O(3) treatment, complete remission was not achieved at the concentrations tested. We suggest that As(2)O(3), in combination with existing treatment modalities, might be a treatment approach for high risk NB patients.  相似文献   
63.
Hp, C3, Gc and Tf serum groups were determined in 66 patients with renal cell carcinoma. Previously reported associations between renal cell carcinoma and the C3F and Gc2 genes were not confirmed. Among female patients a significant excess of GcIF was observed whereas male patients showed a significant excess of TfC3.  相似文献   
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65.
STUDY OBJECTIVE--To determine whether mortality from breast cancer could be reduced by repeated mammographic screening. DESIGN--Birth year cohorts of city population separately randomised into study and control groups. SETTING--Screening clinic outside main hospital. PATIENTS--Women aged over 45; 21,088 invited for screening and 21,195 in control group. INTERVENTIONS--Women in the study group were invited to attend for mammographic screening at intervals of 18-24 months. Five rounds of screening were completed. Breast cancer was treated according to stage at diagnosis. END POINT--Mortality from breast cancer. MEASUREMENTS AND MAIN RESULTS--All women were followed up and classed at end point as alive without breast cancer, alive with breast cancer, dead from breast cancer, or dead from other causes. Cause of death was taken from national mortality registry and for patients with breast cancer was validated independently. Mean follow up was 8.8 years. Altogether 588 cases of breast cancer were diagnosed in the study group and 447 in the control group; 99 v 94 women died of all causes and 63 v 66 women died of breast cancer (no significant difference; relative risk 0.96 (95% confidence interval 0.68 to 1.35)). In the study group 29% more women aged less than 55 died of breast cancer (28 v 22; relative risk 1.29 (0.74 to 2.25)). More women in the study group died from breast cancer in the first seven years; after that the trend reversed, especially in women aged greater than or equal to 55 at entry. Overall, women in the study group aged greater than or equal to 55 had a 20% reduction in mortality from breast cancer (35 v 44; relative risk 0.79 (0.51 to 1.24)). OTHER FINDINGS--In the study group 100 (17%) cancers appeared in intervals between screenings and 107 (18%) in non-attenders; 51 of these women died from breast cancer. Cancers classed as stages II-IV comprised 33% (190/579) of cancers in the study group and 52% (231/443) in the control group. CONCLUSIONS--Invitation to mammographic screening may lead to reduced mortality from breast cancer, at least in women aged 55 or over.  相似文献   
66.
Recombinant phages that encode the complete precursor polypeptide for the 22 kDa polypeptide associated with photosystem II have been serologically selected from two lambda gt11 expression libraries made from polyadenylated RNA of spinach seedlings. The cDNAs hybridize to a 1.3 kb RNA species. The precursor protein is comprised of 274 amino acid residues and carries an N-terminal transit peptide of probably 69 amino acid residues. The mature protein exhibits four predicted transmembrane segments and is shown to be an integral component of photosystem II originating in a single-copy gene. The unique characteristics of this protein are: (i) it is the result of a gene-internal duplication of an ancestor with two membrane spans, (ii) a striking resemblance to LHC I/II, CP24/CP29 apoproteins, and ELIPs, although it does not bind chlorophyll and is present in cyanobacteria, and, as these proteins, (iii) it integrates into the membrane with uncleaved routing signals that display remarkable resemblance to patterns found in bipartite transit peptides.  相似文献   
67.
Estrogen and progesterone binding to endometriotic and endometrial tissue was studied histochemically using estradiol and progesterone fluorochrome derivatives (E2-bovine serum albumin-fluorescein isothiocyanate and progesterone-bovine serum albumin-tetramethylrhodamine isothiocyanate). Thirty endometriotic samples from 21 women were studied, together with endometrial specimens obtained simultaneously from 14 of the women. In 77% of the endometriotic samples binding of the estrogen conjugate was indicated by specific fluorescence in more than half of the epithelial cell population, and in 20% in less than half. The corresponding figures for the progesterone conjugate binding were 75 and 18%, respectively. Blocking studies indicated a reasonable degree of ligand specificity. In endometrial tissue the corresponding figures were 64 and 29%, respectively, for binding of the estrogen conjugate and 54 and 38%, respectively, for binding of the progesterone conjugate. In 7 of 13 cases where evaluable samples of both tissues had been obtained, the relative proportion of fluorescent cells, with either reagent, was similar in the two tissue types. Our results suggest that the cytoplasm of epithelial cells in endometriotic tissue and in uterine endometrium contains specific binding sites for both estrogen and progesterone. The binding pattern of the two conjugates in endometriotic tissue was unrelated to the menstrual phase.  相似文献   
68.
Morphometry was applied to smears of fine needle aspirates from 26 oxyphilic thyroid neoplasms. Thirteen tumors were considered benign as judged from histologic findings and clinical follow-up for 2 to 20 years after the operation. Thirteen tumors were considered malignant histologically; four of these had proven metastases. In each case the mean and standard deviation of the projected nuclear area were calculated from 200 nuclei in the smear. Our results indicate that morphometric estimation of mean nuclear size and/or degree of anisokaryosis is of no practical value in distinguishing between benign and malignant thyroid neoplasms of the oxyphilic type.  相似文献   
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