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121.
Taylor VM Jackson JC Schwartz SM Tu SP Thompson B 《Asian American and Pacific Islander journal of health》1996,4(4):327-342
PURPOSE OF THE PAPER: Relatively little attention has been paid to cervical cancer control in Asian American populations. We summarize available cervical cancer incidence and mortality dat, present information on levels of Pap testing use, and review factors that may be associated with cervical cancer screening participation. METHODS: We reviewed the literature pertaining to cervical cancer and Pap testing among Asian populations in North America. PRINCIPAL FINDINGS: Cancer registry data suggest that women from Southease Asia have a nearly fivefold increased risk of invasive cervical cancer (when compared to non­Hispanic White women). Filipino and Korean populations also have elevated risks. The excess invasive cervical cancer burden appears to be concentrated among women aged 40 and older. Pap testing use by Asians is less than for all toher racial/ethnic groups in the U.S., and recent studies suggest that over onethird of Vietnamese immigrants have never been screened. Barriers to Pap testing participation by less acculturated Asian women include a lack of familiarity with Western preventive concepts, a lack of knowledge concerning cervical cancer, embarrassment in association with gynecologic exams, the role of women in some Asian cultures, the cost of health care, and language difficulties. CONCLUSIONS: There is a considerable need for ethnoculturally appropriate cervical cancer control programs targeting Asian American populations. RELEVANCE TO ASIAN PACIFIC ISLANDER AMERICAN POPULATIONS: This paper is relevant to Asian American women from East, South, Southeast, and Island Asia. 相似文献
122.
Mr. J. R. McGregor M.D. F.R.C.S. D. H. Reinbach F.R.C.S. S. W. Dahill B.Sc. M.B. Ch.B. P. J. O'Dwyer M.Ch. F.R.C.S.I. 《Diseases of the colon and rectum》1993,36(9):834-839
Viable intraluminal tumor cells can penetrate a clinically intact rodent colonic anastomosis and give rise to perianastomotic tumor growth. The aim of this study was to determine whether transanastomotic cell migration can be prevented by fibrin-based tissue sealant. Following distal colonic transection and reanastomosis with 5/0 silk sutures, Fischer F344 rats were randomly allocated to three experimental groups. In Group A, a circumferential ring of tissue sealant was placed around the serosal surface of the anastomosis; in Group B, sealant was limited to 50 percent of the anastomotic circumference; and, in Group C, no sealant was applied. All rats then had 10 5 Mtln 3 carcinoma cells injected into the proximal colonic lumen via a rectal catheter. The incidence of perianastomotic tumor at 21 days was significantly lower in Group A (3 of 14 animals) than in Group B (11 of 16 rats) (P =0.012; Fisher's exact test) or Group C (10 of 14 rats;P=0.011). A further experiment demonstrated that sealant did not protect the anastomosis when tumor cells were instilled directly into the peritoneal cavity. A topical carcinocidal action therefore appears unlikely, but our results suggest that a circumferential anastomotic ring of fibrin sealant forms an effective mechanical barrier preventing intraluminal tumor cells from reaching the peritoneal cavity. 相似文献
123.
Kinds and locations of mutations arising spontaneously in the coding region of theHPRT gene of finite-life-span diploid human fibroblasts 总被引:1,自引:0,他引:1
W. Glenn McGregor Veronica M. Maher J. Justin McCormick 《Somatic Cell and Molecular Genetics》1991,17(5):463-469
Spontaneous thioguanine-resistant mutants were derived from populations of finite-life-span, diploid human fibroblasts by means of a fluctuation analysis. cDNA was prepared from mutantHPRT mRNA and amplified by the polymerase chain reaction, and the sequence of the product was analyzed. Exon deletions, which very likely arose from mutations in the intron splice site consensus sequences, were found in 10 of the 37 mutants examined (27% of the total). Among the 28 mutations in the coding sequence, base pair substitutions predominated (89%). With the exception of one base pair involved in a tandem mutation, all base pair substitutions resulted in alterations in the predicted amino acid sequence of the protein. In addition there were three frameshift mutations, consisting of the deletion of one or two base pairs. Although mutations occurred throughout the coding sequence, 50% (14/28) were found in the 5 portion of exon 3. 相似文献
124.
125.
The synthesis of a new penicillin, disodium D-6-[alpha-(1,2,4-triazine-3,5-dione-6-carboxyamido)-4-hydroxyphenylacetamido]penicillanate (BL-P1908), is described. The compound shows superior in vitro activity against Pseudomonas aeruginosa compared to carbenicillin and ticarcillin and produces higher intramuscular serum levels in mice than does carbenicillin. 相似文献
126.
Tolcos M McGregor H Walker D Rees S 《Journal of neuropathology and experimental neurology》2000,59(3):218-228
Maternal cigarette smoking during pregnancy is associated with a significantly increased risk of Sudden Infant Death Syndrome (SIDS). This study investigated the effects of prenatal exposure to carbon monoxide (CO), a major component of cigarette smoke, on the neuroglial and neurochemical development of the medulla in the fetal guinea pig. Pregnant guinea pigs were exposed to 200 p.p.m CO for 10 h per day from day 23-25 of gestation (term = 68 days) until day 61-63, at which time fetuses were removed and brains collected for analysis. Using immunohistochemistry and quantitative image analysis, examination of the medulla of CO-exposed fetuses revealed a significant decrease in tyrosine hydroxylase-immunoreactivity (TH-IR) in the nucleus tractus solitarius, dorsal motor nucleus of the vagus (DMV), area postrema, intermediate reticular nucleus, and the ventrolateral medulla (VLM), and a significant increase in choline acetyltransferase-immunoreactivity (ChAT-IR) in the DMV and hypoglossal nucleus compared with controls. There was no difference between groups in immunoreactivity for the m2 muscarinic acetylcholine receptor, substance P- or met-enkephalin in any of the medullary nuclei examined, nor was there evidence of reactive astrogliosis. The results show that prenatal exposure to CO affects cholinergic and catecholaminergic pathways in the medulla of the guinea pig fetus, particularly in cardiorespiratory centers, regions thought to be compromised in SIDS. 相似文献
127.
Brenda Faiola Alison K Bauer Elizabeth S Fuller Victoria A Wong Linda J Pluta Diane J Abernethy James B Mangum Jeffrey I Everitt Leslie Recio 《Toxicological sciences》2003,75(2):321-332
Benzene, a carcinogen that induces chromosomal breaks, is strongly associated with leukemias in humans. Possible genetic determinants of benzene susceptibility include proteins involved in repair of benzene-induced DNA damage. The catalytic subunit of DNA-dependent protein kinase (DNA-PKcs), encoded by Prkdc, is one such protein. DNA-PKcs is involved in the nonhomologous end-joining (NHEJ) pathway of DNA double-strand break (DSB) repair. Here we compared the toxic effects of benzene on mice (C57BL/6 and 129/Sv) homozygous for the wild-type Prkdc allele and mice (129/SvJ) homozygous for a Prkdc functional polymorphism that leads to diminished DNA-PK activity and enhanced apoptosis in response to radiation-induced damage. Male and female mice were exposed to 0, 10, 50, or 100 ppm benzene for 6 h/d, 5 d/week for 2 weeks. Male mice were more susceptible to benzene toxicity compared with females. Hematotoxicity was evident in all male mice but was not seen in female mice. We observed similar, large increases in both micronucleated erythrocyte populations in all male mice. Female mice had smaller but significant increases in micronucleated cells. The p53-dependent response was induced in all strains and genders of mice following benzene exposure, as indicated by an increase in p21 mRNA levels in bone marrow that frequently corresponded with cell cycle arrest in G2/M. Prkdc does not appear to be a significant genetic susceptibility factor for acute benzene toxicity. Moreover, the role of NHEJ, mediated by DNA-PK, in restoring genomic integrity following benzene-induced DSB remains equivocal. 相似文献
128.
Deborah P Waber Lewis B Silverman Lori Catania William Mautz Montse Rue Richard D Gelber Donna E Levy Meredith A Goldwasser Heather Adams Annie Dufresne Victoria Metzger Ivonne Romero Nancy J Tarbell Virginia Kimball Dalton Stephen E Sallan 《Journal of clinical oncology》2004,22(13):2701-2707
PURPOSE: We evaluated 8-year survival and late neuropsychologic toxicity in children with acute lymphoblastic leukemia treated in a randomized clinical trial to test whether hyperfractionated (twice daily) cranial radiation therapy (CRT) can reduce incidence and severity of late toxicities associated with 18 Gy of CRT. PATIENTS AND METHODS: Between 1987 and 1995, 369 children treated on two consecutive Dana-Farber Cancer Institute Consortium protocols for high-risk acute lymphoblastic leukemia were randomly assigned to conventionally fractionated CRT (CFX) or hyperfractionated CRT (HFX) to a total dose of 18 Gy. Neuropsychologic testing was completed for 125 of 287 children in continuous complete remission. Event-free and overall survival, as well as neuropsychologic function, were compared for the two arms of the protocol. RESULTS: Eight-year event-free survival (+/- SE) was 80% +/- 3% for children randomly assigned to CFX and 72% +/- 3% for HFX (P =.06). Overall survival was 85% +/- 3% for CFX and 78% +/- 3% for HFX (P =.06). CNS relapses occurred in 2.8% of patients receiving CFX and 2.7% receiving HFX (P =.99). Cognitive function for both groups was solidly in the average range, with no group differences in intelligence, academic achievement, visuospatial reasoning, or verbal learning. Children on the HFX arm exhibited a modest advantage for visual memory (P <.05). CONCLUSION: HFX provides no benefit in terms of cognitive late effects and may compromise antileukemic efficacy. HFX should not be substituted for conventionally dosed CRT in children who require radiation therapy for treatment of acute lymphoblastic leukemia. 相似文献
129.
130.
Changes in the expression of the type-2 but not the type-1 cyclo-oxygenase enzyme in chorion-decidua with the onset of labour 总被引:3,自引:0,他引:3
Donna Slater Senior Research Fellow Victoria Allport Research Assistant Phillip Bennett Professor 《BJOG : an international journal of obstetrics and gynaecology》1998,105(7):745-748
Objective To determine the relative expression of cyclo-oxygenase (COX)-1 and COX-2 in the chorion-decidual part of human fetal membranes following delivery at term and to identify any changes in expression associated with labour.
Methods Fetal membranes were collected from 12 term pregnancies before labour following elective caesarean section and from 12 spontaneous vaginal deliveries. Expression of COX-1 and COX-2 mRNA was measured using a previously validated quantitative RT-PCR assay.
Results COX-2 expression exceeded that of COX-1 by approximately eight-fold. COX1 expression did not change but COX-2 expression was found to increase four-fold with labour.
Conclusions Chorion-decidua has the capacity to contribute to the increase in prostaglandin synthesis within the uterus associated with labour. As in the amnion, it is COX-2 and not COX-1 which is upregulated with labour. COX-2 selective anti-prostaglandins should therefore be as effective as nonselective drugs in inhibition of fetal membrane prostaglandin synthesis. 相似文献
Methods Fetal membranes were collected from 12 term pregnancies before labour following elective caesarean section and from 12 spontaneous vaginal deliveries. Expression of COX-1 and COX-2 mRNA was measured using a previously validated quantitative RT-PCR assay.
Results COX-2 expression exceeded that of COX-1 by approximately eight-fold. COX1 expression did not change but COX-2 expression was found to increase four-fold with labour.
Conclusions Chorion-decidua has the capacity to contribute to the increase in prostaglandin synthesis within the uterus associated with labour. As in the amnion, it is COX-2 and not COX-1 which is upregulated with labour. COX-2 selective anti-prostaglandins should therefore be as effective as nonselective drugs in inhibition of fetal membrane prostaglandin synthesis. 相似文献