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排序方式: 共有778条查询结果,搜索用时 15 毫秒
1.
John S. Witte Giske Ursin Jack Siemiatycki W. Douglas Thompson Annali Paganini-Hill Robert W. Haile 《Breast cancer research and treatment》1997,42(3):243-251
We investigated associations between diet and premenopausal bilateral breast cancer in a familial matched case-control study. We studied 140 cases from population-based registries in Los Angeles County (California) and Connecticut, and from the major hospitals in the southern parts of the Province of Quebec. Unaffected sisters of the cases served as matched controls (222 total). Dietary intake were assessed with a food frequency questionnaire. Total fat, monounsaturated fat, polyunsaturated fat, oleic acid, and linoleic acid intake was inversely associated with premenopausal bilateral breast cancer risk. Consumption of carbohydrates (and sweetened beverages) was associated with an increased risk. We observed no associations for dietary fiber, antioxidants, or major food groupings, but we did observe inverse associations for intake of low fat dairy products and tofu. These findings suggest that monounsaturated and polyunsaturated fats, as well as soy foods, might reduce the risk of premenopausal bilateral breast cancer. 相似文献
2.
Fas-mediated apoptosis in cultured human eosinophils 总被引:11,自引:1,他引:10
3.
Possible heterogeneity in the segregation pattern of breast cancer in families with bilateral breast cancer 总被引:2,自引:0,他引:2
A M Goldstein R W Haile S E Hodge A Paganini-Hill M A Spence 《Genetic epidemiology》1988,5(2):121-133
We investigated the segregation pattern of breast cancer in families with bilateral breast cancer, classifying families with respect to menopausal status (premenopausal versus postmenopausal) and the interval between diagnosis of the two primary tumors in the probands. Probands were "synchronous" if both primaries were diagnosed within 1 year; "asynchronous" if the interval was at least 2 years. Results for four complex segregation analyses are here presented; the findings support heterogeneity in the transmission of breast cancer. In the asynchronous premenopausal-cases-only analysis, a dominant Mendelian gene can explain the breast cancer pattern. A recessive gene is sufficient to describe the breast cancer distribution in the synchronous premenopausal-cases-only analysis. The synchronous all-cases and the asynchronous all-cases analyses add postmenopausal cases of breast cancer to the premenopausal ones, considering any case to be affected. In the asynchronous all-cases analysis, neither the single-locus model nor the mixed model (that is, a major locus plus other factors, genetic and/or cultural) without generation differences in heritability can be rejected by the unrestricted mixed model with generation differences in heritability. For the synchronous all-cases analysis, a mixed model with generation differences in heritability is necessary to explain the breast cancer transmission. Potential sources of error and possible interpretations are discussed. 相似文献
4.
5.
Computer simulation of Rocky Mountain spotted fever transmission by the American dog tick (Acari: Ixodidae) 总被引:1,自引:0,他引:1
A computer model was developed for simulation of the transmission of Rickettsia rickettsii, the causative agent of Rocky Mountain spotted fever (RMSF), by the American dog tick, Dermacentor variabilis (Say). The model of RMSF was combined with a model for population dynamics of the American dog tick and included simulation of infection and transmission of rickettsiae between ticks and host mammals and transmission of RMSF to humans. The model simulated the effects of biotic and environmental variables such as weather, host density, habitat, transovarial transmission, fecundity of infected ticks, and infectivity level of ticks and mammals. Some parameters in the model were fitted by iterative simulations to produce realistic rates of R. rickettsii infection in adult ticks and small and medium-sized mammal hosts. Parameters also were fitted to yield the historical average number of RMSF cases for Virginia. Comparisons of the simulated and actual number of cases for nine other states indicated a reasonable level of validity for the model. A theoretical tick density threshold of 252 unfed adult ticks/ha for transmission of RMSF was determined from a relationship between rate of transmission to humans and density of ticks. The transmission threshold can be used for additional modeling efforts to study the effects of management technologies on tick densities and RMSF human cases. The model can serve as a framework for modeling other tick-borne diseases such as Lyme disease, babesiosis, and heartwater. 相似文献
6.
G. Melles F. Lander F. Rietveld L. Remeijer W Beekhuis P. Binder 《The British journal of ophthalmology》1999,83(3):327-333
AIMS: To describe a new surgical technique for deep stromal anterior lamellar keratoplasty. METHODS: In eye bank eyes and sighted human eyes, aqueous was exchanged by air, to visualise the posterior corneal surface--that is, the "air to endothelium" interface. Through a 5.0 mm scleral incision, a deep stromal pocket was created across the cornea, using the air to endothelium interface as a reference plane for dissection depth. The pocket was filled with viscoelastic, and an anterior corneal lamella was excised. A full thickness donor button was sutured into the recipient bed after stripping its Descemet's membrane. RESULTS: In 25 consecutive human eye bank eyes, a 12% microperforation rate was found. Corneal dissection depth averaged 95.4% (SD 2.7%). Six patient eyes had uneventful surgeries; in a seventh eye, perforation of the lamellar bed occurred. All transplants cleared. Central pachymetry ranged from 0.62 to 0.73 mm. CONCLUSION: With this technique a deep stromal anterior lamellar keratoplasty can be performed with the donor to recipient interface just anterior to the posterior corneal surface. The technique has the advantage that the dissection can be completed in the event of inadvertent microperforation, or that the procedure can be aborted to perform a planned penetrating keratoplasty. 相似文献
7.
A reappraisal of time trends in ulcer disease: factors related to changes in ulcer hospitalization and mortality rates. 总被引:1,自引:0,他引:1
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There has been a dramatic decline in reported hospitalization and mortality rates for peptic ulcer disease in the past two decades. Data from the National Center for Health Statistics and from the Commission on Professional and Hospital Activities were examined to determine the cause(s) for this decline. Gastric and duodenal ulcer mortality rates decreased by 58 per cent and 68 per cent, respectively, from 1962 to 1978; changes in criteria for selecting the underlying cause of death might account for some of this apparent decrease. Hospitalization rates for duodenal ulcers decreased nearly 50 per cent from 1970 to 1978, but hospitalizations for gastric ulcers did not decrease. During this same time period, hospitalizations for peptic ulcers as one of the "all listed" causes remained stable, and hospitalizations for a closely related diagnosis, gastritis/duodenitis, increased. Changes in coding practices, hospitalization criteria, and diagnostic procedures appear to have contributed to the decline in reported hospitalization and mortality rates for peptic ulcer disease. 相似文献
8.
Dawit K. Mekonnen Jowel Choufani Elizabeth Bryan Beliyou Haile Claudia Ringler 《Maternal & child nutrition》2022,18(4)
Evidence on the potential for agricultural intensification to improve nutrition has grown considerably. While small‐scale irrigation is a key factor driving agricultural intensification in sub‐Saharan Africa, its impact on nutrition has not yet been thoroughly explored. In this study, we assess the impact of adoption of small‐scale irrigation in Ethiopia and Tanzania on household and women''s dietary diversity, as well as children''s nutrition. We use two rounds of primary data collected from irrigators and nonirrigators in Ethiopia and Tanzania. We used a panel fixed effects econometric approach to control for observed household, women and children specific characteristics as well as observed and unobserved time‐invariant confounding factors. The results show that among Ethiopian households who reported having faced drought, women in irrigating households have higher Women''s Dietary Diversity Score (WDDS) compared to women in nonirrigating households. In Tanzania, women in irrigating households have higher WDDS compared to nonirrigators and the impact of irrigation on WDDS more than doubles among households facing drought. In addition, among Tanzanian households who reported having faced a drought shock, irrigating households have higher Household Dietary Diversity Score compared to nonirrigators. Children in irrigating households in Ethiopia have weight‐for‐height z‐scores (WHZ) that are 0.87 SDs higher, on average, than WHZ of children in nonirrigating households. In Tanzania, irrigation leads to higher WHZ‐scores in children under‐five among households who reported having experienced a drought in the 5 years preceding the survey. The study shows small‐scale irrigation has a strong effect on households'' economic access to food and on nutritional outcomes of women and children. 相似文献
9.
Corneal sensitivity in nephropathic cystinosis 总被引:2,自引:0,他引:2
We measured corneal sensitivity in 14 patients with infantile nephropathic cystinosis and in 13 age-matched controls. All patients with cystinosis had the pathognomonic anterior segment findings of crystal deposition within conjunctiva and cornea. Transcutaneous stimulation of the supraorbital nerve and surface electromyographic recording of the orbicularis oculi muscle performed on four patients showed a normal afferent limb to the blink reflex. The corneal sensitivity in patients with cystinosis was 3.18 g/mm2; in the control subjects it was 0.43 g/mm2. This difference was statistically significant (P less than .001). 相似文献
10.
Yiouli P. Ktena Michael A. Koldobskiy Michael I. Barbato Han-Hsuan Fu Leo Luznik Nicolas J. Llosa Azeb Haile Orly R. Klein Chen Liu Christopher J. Gamper Kenneth R. Cooke 《The Journal of clinical investigation》2022,132(13)
DNA methyltransferase 3a (DNMT3a) is an important part of the epigenetic machinery that stabilizes patterns of activated T cell responses. We hypothesized that donor T cell DNMT3a regulates alloreactivity after allogeneic blood and marrow transplantation (allo-BMT). T cell conditional Dnmt3a KO mice were used as donors in allo-BMT models. Mice receiving allo-BMT from KO donors developed severe acute graft-versus-host disease (aGVHD), with increases in inflammatory cytokine levels and organ histopathology scores. KO T cells migrated and proliferated in secondary lymphoid organs earlier and demonstrated an advantage in trafficking to the small intestine. Donor T cell subsets were purified after BMT for whole-genome bisulfite sequencing (WGBS) and RNA-Seq. KO T cells had global methylation similar to that of WT cells, with distinct, localized areas of hypomethylation. Using a highly sensitive computational method, we produced a comprehensive profile of the altered epigenome landscape. Hypomethylation corresponded with changes in gene expression in several pathways of T cell signaling and differentiation. Additionally, Dnmt3a-KO T cells resulted in superior graft-versus-tumor activity. Our findings demonstrate a critical role for DNMT3a in regulating T cell alloreactivity and reveal pathways that control T cell tolerance. These results also provide a platform for deciphering clinical data that associate donor DNMT3a mutations with increased GVHD, decreased relapse, and improved survival. 相似文献