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121.
Dulon M Weichenthal M Blettner M Breitbart M Hetzer M Greinert R Baumgardt-Elms C Breitbart EW 《Journal of clinical epidemiology》2002,55(11):1075-1081
The occurrence and number of melanocytic nevi are among the most important known risk factors for the development of malignant melanoma. Studying the causes of nevi should lead to successful strategies in the prevention of melanoma. Among 11,478 white German children of preschool age the association between benign melanocytic nevi and a number of risk factors for skin cancer was examined. We found that subjects with a reported history of increased sun exposure, for example, painful sunburns, and an increased number of holidays in foreign countries with a sunny climate had significantly higher nevus counts than individuals without these characteristics. Our results provide further evidence that nevus counts may not only be part of a genetic predisposition but also a result of increased exposure to ultraviolet radiation. Together with the fact that a high nevus count is the most relevant risk factor for malignant melanoma, the results strongly indicate a connection between UV-radiation and the development of melanocytic skin cancer. In conclusion, strategies to reduce the incidence of melanoma should begin with young children. 相似文献
122.
Tilanus-Linthorst M Verhoog L Obdeijn IM Bartels K Menke-Pluymers M Eggermont A Klijn J Meijers-Heijboer H van der Kwast T Brekelmans C 《International journal of cancer. Journal international du cancer》2002,102(1):91-95
Female BRCA1/2 mutation carriers develop in up to 50% breast cancer (BC) before age 50 years. We investigated whether the specific histologic features of BRCA1/2-associated breast cancer influence imaging. We correlated the mammographic results with the histology of 34 BC in BRCA1/2 mutation carriers and 34 sporadic cancers in patients, matched for age and year of diagnosis. Mammography was significantly more frequently false-negative in carriers than controls (62% vs. 29% p = 0.01), despite comparable tumor size (mean solidus in circle 1.51 vs. 1.75) and breast density (high 41% vs. 53%). The image in carriers was significantly less as spiculated mass (6 vs. 18 p = 0.01). Cancers of BRCA1/2 mutation carriers had frequently higher mitotic counts (p < 0.0001) and prominent pushing margins around the tumor (p = 0.08) (p = 0.05 for 32 BRCA1). We also observed that prominent "pushing margins" correlated significantly with a false-negative mammography (p = 0.005) and with a mammographic image of a smooth, not a spiculated, mass (p = 0.01). False-negative mammography correlated independently with: BRCA1/2 mutation (p = 0.02), prominent pushing margins (p = 0.03) and high breast density (p = 0.01). MRI was carried out in 12 carriers, had 100% sensitivity and detected 5 cancers, still occult at physical examination and mammography. A BRCA1/2 mutation and high breast density at mammography contribute independently to false-negative mammography results. In mutation carriers any mammographic mass must be regarded with suspicion. Pushing margins of the tumor partly explain these results. For early BC detection in mutation carriers additional methods like MRI may be needed. This may not be necessary in other young women with breast symptoms. 相似文献
123.
Growth hormone induces age-dependent alteration in the expression of hippocampal growth hormone receptor and N-methyl-D-aspartate receptor subunits gene transcripts in male rats 下载免费PDF全文
124.
Polymorphisms in the DNA repair genes XPC, XPD, and XPG and risk of cutaneous melanoma: a case-control analysis. 总被引:2,自引:0,他引:2
Chunying Li Zhibin Hu Zhensheng Liu Li-E Wang Sara S Strom Jeffrey E Gershenwald Jeffrey E Lee Merrick I Ross Paul F Mansfield Janice N Cormier Victor G Prieto Madeleine Duvic Elizabeth A Grimm Qingyi Wei 《Cancer epidemiology, biomarkers & prevention》2006,15(12):2526-2532
Sunlight causes DNA damage, including bulky lesions that are removed effectively by the nucleotide-excision repair (NER) pathway. There are at least eight core NER proteins participating in the pathway, and genetic variations in their genes may alter NER functions. We hypothesized that some NER variants are associated with risk of cutaneous melanoma. In a hospital-based case-control study of 602 non-Hispanic White patients with cutaneous melanoma and 603 age- and sex-matched cancer-free controls, we genotyped five common non-synonymous single-nucleotide polymorphisms identified to date and assessed their associations with risk of cutaneous melanoma. We found that a significantly increased risk of cutaneous melanoma was associated with XPD 751Lys/Gln [adjusted odds ratio (OR), 1.55 and 95% confidence interval (95% CI), 1.12-2.16] and XPD 751Gln/Gln (OR, 1.66; 95% CI, 1.03-2.68) genotypes compared with the XPD 751Lys/Lys genotype as well as XPD312Asp/Asn (OR, 1.54; 95% CI, 1.11-2.12) and XPD312Asn/Asn (OR, 1.75; 95% CI, 1.05-2.90) genotypes compared with the XPD 312Asp/Asp genotype. This increased risk was not observed in the other three XPC and XPG single-nucleotide polymorphisms. Moreover, the number of the observed XPD at-risk genotypes (i.e., 312Asn/Asn+Asn/Asp and 751Gln/Gln+Lys/Gln) was associated with cutaneous melanoma risk in a dose-response manner (OR, 1.47; 95% CI, 0.97-2.23 for one at-risk genotype; OR, 1.83; 95% CI, 1.29-2.61 for two at-risk genotypes; P(trend) < 0.001). However, we found no evidence of any interaction between XPD genotypes with XPC and XPG genotypes or the known risk factors. We concluded that genetic variants of the XPD gene might serve as biomarkers for susceptibility to cutaneous melanoma. 相似文献
125.
126.
Madeleine H. Shearer 《分娩》1973,1(1):12-18
Recently I returned to teaching prenatal classes after an absence of 18 months. In my first class was a young girl who had been told that her baby was breech. She asked me if I would come with her and her husband in labor. I agreed, anticipating a chance to find out what was new at her teaching hospital and to help her, as well. A few weeks later I got her call, drove over and made my way up to her little labor room. For five minutes we talked. Then she panted quietly and rubbed her abdomen, her husband holding her other hand. At this point the door was propped open and a cabinet-sized machine was rolled into the room, pushed by a nurse. It stopped next to the bed, with a brief pause for the removal of the husband's chair to the corridor outside. The hand which had held the husband's was searched for a vein, and an intrevenous drip of glucose installed. The other arm was connected to a continuous blood pressure gauge. The abdomen was encircled with two belts and the electronic devices on the belts were squirted with jelly and planted firmly on the mother's abdomen, the belts then tightened securely. The monitor was turned on and out rolled a continuous strip of paper bearing the fetal heart rate tracing, the uterine contraction tracing, and the blood pressure tracing. The husband found a perch on a window sill across the room. For the next 7 hours a nurse or resident would come in at 30 minute intervals, study the tracing carefully, and tell the mother that all was well. In the next weeks I learned that nearly half of the women in my classes were being monitored, and the trend has increased in many areas. As a parent educator, I needed to know about fetal monitoring. Are the benefits so great as to justify such absolute domination of labor by machines? Is monitoring too complex to explain ahead of time to parents? I was disturbed by the lack of personal contact on the part of the staff, by the unseated husband and the lack of mobility of the mother. These worries led me to begin a search of the literature and correspondence with monitor manufacturers and several obstetricians who have pioneered in their development. 相似文献
127.
Liu W Hill D Gibbs AF Tempany M Howe C Borland R Morand M Kelly JW 《Melanoma research》2005,15(6):549-554
The ABCD(E) rule and the seven-point checklist are diagnostic aids that have proven to be useful in the hands of physicians; however, little is known of their value to patients with respect to aiding self-detection. The objective of this study was to investigate features that patients notice when identifying melanomas and to explore how well these features correspond to the ABCD(E) rule and the seven-point checklist. A retrospective, modified, case-control study involving patient interviews was performed. All interviews were conducted through the private consulting rooms of a Melbourne dermatologist (JWK) and a Newcastle plastic surgeon (CH) prior to the result of pathology being known to the patients and the interviewers. Sixty-seven patients with benign pigmented skin lesions and 46 patients with melanomas were included. Using a logistic regression model, the change in size/new lesion and change in colour (major criteria, seven-point checklist) were most useful in differentiating between melanomas and benign pigmented lesions in the hands of patients [odds ratio (OR), 4.74; 95% confidence interval (CI), 1.85-12.19; P=0.001; OR, 4.27; 95% CI, 1.62-11.26; P=0.003, respectively). The ABCD(E) rule failed to discriminate between melanoma and other benign pigmented skin lesions. It can be concluded that, of the patients' observations, changes in size or colour were most important in distinguishing between benign pigmented lesions and melanomas. Such features therefore deserve emphasis in public education campaigns. Medical professionals should also remember to seek a history of change in assessing pigmented skin lesions. 相似文献
128.
Polder K Wang C Duvic M Diwan AH Parks D Jankov A Walker PL Tong AT Bull J Dang NH 《Leukemia & lymphoma》2005,46(12):1807-1811
Denileukin diftitox (DAB389IL-2 or Ontak®) is a synthetic fusion protein with demonstrated efficacy in a number of lymphoproliferative disorders, including non-Hodgkin's lymphoma. We report the case of a 45-year-old man with progressive follicular large cell lymphoma following an autologous stem cell transplant treated with denileukin diftitox who developed a fatal skin rash associated with extensive erythema, edema and large bullae involving his entire body. The clinical features and pathology were compatible with toxic epidermal necrolysis. This is the first reported case of toxic epidermal necrolysis in the literature associated with denileukin diftitox. 相似文献
129.
In vitro and in vivo evaluation of pectin beads for the colon delivery of beta-lactamases 总被引:1,自引:0,他引:1
The aim of the present study was to provide a "proof of concept" of colon delivery of beta-lactamases by pectin beads aiming to degrade residual beta-lactam antibiotics, in order to prevent the emergence of resistant bacterial strains.Pectin beads were prepared according to ionotropic gelation method using CaCl2 as a gelling agent. Particles were then washed and soaked in polyethylenimine (PEI). Coating beads with PEI considerably improved their stability in simulated intestinal medium. In vitro studies showed that beta-lactamases were released from pectin beads in colonic medium due to the action of pectinolytic enzymes. When ampicillin was added to this medium, the release of beta-lactamases induced, as expected, the antibiotic inactivation. Finally, after oral administration of loaded-beads to CD1 mice, beta-lactamases were retrieved in high concentrations in faeces. Observation by SEM of beads extracted from mice intestinal tracts concluded the core degradation of beads without any modification of the PEI coating layer.This study demonstrates that a multiparticulate system with suitable characteristics for site-specific colonic delivery can be prepared. This system could be used to target beta-lactamases to the colon in order to hydrolyse antibiotic residues during treatment and prevent their impact on colonic microflora. 相似文献
130.
Brugler L Stankovic AK Schlefer M Bernstein L 《Nutrition (Burbank, Los Angeles County, Calif.)》2005,21(6):650-658
OBJECTIVE: We assessed admission screening information that best identifies patients who are at risk for malnutrition-related complications (MRCs). METHODS: We evaluated 13 patient characteristics associated with MRC for adults screened over a 3-mo period (n = 448) to determine which factors correlated best with the risk level assigned. The existing screen stratified patients into four levels defined as no risk, mild risk, moderate, and high risk for MRC. The analyzed variables were weight for height, wound, surgery/cancer therapy, fever, vomiting/diarrhea, poor oral intake, no oral intake, unplanned weight loss, malnutrition-related admission diagnosis, serum albumin, white blood cell count, hemoglobin, and total lymphocyte count. We modeled the relation between assigned MRC and the predictors by using state-of-the-art methods. RESULTS: The characteristics that correlated best with MRC risk level assignment were occurrence of a wound, poor oral intake, malnutrition-related admission diagnosis, serum albumin value, hemoglobin value, and total lymphocyte count. A model using four variables (malnutrition-related admission diagnosis, serum albumin value, hemoglobin value, and total lymphocyte count) was almost as good as that using six predictors. CONCLUSIONS: The ability of admission information to accurately reflect MRC risk is crucial to early initiation of restorative medical nutritional therapy. There is currently no uniform or proved standard for identifying MRC risk within 24 h of acute care admission. The ideal nutritional screen correlates well with the occurrence of MRC and also uses data routinely obtained at admission. The models described can be uniformly used by hospitals to screen patients for MRC risk. 相似文献