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91.
Postoperative radiotherapy for locally advanced colon cancer 总被引:1,自引:0,他引:1
Dr. E. Henry Amos MD William M. Mendenhall MD Patricia J. McCarty BA John O. Gage MD J. Logan Emlet MD Gerald C. Lowrey MD Craig A. Peterson MD Warren R. Amos MD 《Annals of surgical oncology》1996,3(5):431-436
Background: The role of adjuvant postoperative radiotherapy for locally advanced colon cancer is not well documented.
Methods: Seventy-eight patients who underwent a complete resection of B2-C colon cancer received postoperative radiotherapy. Twenty-eight
patients received ⩽45 Gy; 50 patients received 50–55 Gy. Twenty-seven patients received adjuvant fluorouracil-based chemotherapy.
All patients were followed for a minimum of 3 years; no patients were lost to follow-up.
Results: The overall local control rate was 88%. The 5-year actuarial rate of local control was 96% after 50–55 Gy postoperative radiotherapy
compared with 76% after <50 Gy (p=0.0095). Multivariate analysis of local control showed that only radiotherapy dose significantly
influenced this end point. Cause-specific survival rates at 5 years were B2, 67%; B3, 90%; C1, 100%; C2, 61%; C3, 36%; and
overall, 63%. Multivariate analysis of cause-specific survival showed that only stage significantly influenced this end point.
Bowel obstruction caused by adhesions developed in three patients and required a laparotomy; radiation-induced sarcoma developed
in one additional patient.
Conclusions: Postoperative radiotherapy appears to reduce the risk of local recurrence in patients with locally advanced colon cancer.
The optimal dose is probably 50–55 Gy at 1.8 Gy per fraction. Postoperative radiotherapy may improve cause-specific survival
for patients with stages B3 and C2 cancers. 相似文献
92.
G Hussein Rassool MSc BA RMN RCNT RNT FETC CertEd CertCouns CertSupervision & Consultation 《Journal of advanced nursing》1993,18(9):1401-1407
The widespread use and misuse of alcohol, drug and other psychoactive substances are major health and social concerns that affect the lives of many The social and health sequelae of psychoactive drugs and alcohol are preventable and manageable with minimal interventions Nurses and other health workers can effectively respond to substance misuse problems and their existing generic skills can be easily adapted in working with substance misusers This paper considers some of the issues such as the extent of the problem, attitudinal considerations, response to substance misusers and a brief outline of the role of the nurse The urgent need for education and training in substance misuse and addictive behaviour for nurse practitioners is also addressed 相似文献
93.
Tai-Chan Peng MD Robert P. Kusy PhD Philip F. Hirsch PhD John R. Hagaman BA 《Alcoholism, clinical and experimental research》1988,12(5):655-659
Chronic ingestion of ethanol resulted in ultrastructural and mechanical changes in rat femurs. Scanning electron microscopy of the distal end of the femur revealed that the trabeculae of bones from ethanol-fed rats were thinner, more columnar, and more extensive than those from control rats. Three-point bending tests of the rat femurs showed that the maximum force or so-called "strength" required to break the bone was less in ethanol- than in control-fed animals. A significant inverse correlation was observed between the strength required to break the femur and the dose of ethanol calculated on a body weight basis. For the first time our study presents quantitative proof that a relationship exists between bone strength and the consumption of ethanol in rats. The study revealed that ethanol consumption resulted in a weaker femur compared to controls. We suggest that a common mechanism may be responsible for the decreased bone strength of ethanol-fed rats and the increased incidence of fractures in human alcoholics. 相似文献
94.
Summary The effects of personality characteristics on social support and hence risk of depression are explored in a group of 150 largely working-class mothers, a subsample of 400 women who took part in a prospective study. This established that once those with depression at first interview were excluded, practically all of the onsets of depression in the follow-up year occurred among 150 women with a severe event or major difficulty — that is a provoking agent. It was also found that low self-esteem and lack of support from a core tie at the time of the crisis was associated with a considerably increased risk. In the subsample as a whole, measures of dependency and attitudinal constraints to support taken at first interview were not associated with risk of depression. But, it is argued, any enduring personality traits that play a role in the link between lack of support and depression would most likely be seen in a smaller group, namely those who had had early inadequate parenting. And the most promising lead concerning the role of personality characteristics did in fact emerge in relation to a small high risk group with such parenting. Most of them had low self-esteem, and they appeared to confide in inappropriate and unreliable sources of support at time of crisis. 相似文献
95.
为观察达英-35治疗多囊卵巢综合征(PCOS)在明显降低黄体生成素(LH)及睾酮(T)水平,改善患者内分泌状况的同时,是否改善其胰岛素抵抗(IR),35例PCOS患者服用复方醋酸环丙孕酮(达英-35)治疗3个周期,观察用药前后临床特征、血清激素水平、空腹血糖、空腹胰岛素(FIN)的变化.结果显示,治疗后34例PCOS患者月经恢复,多毛及痤疮评分下降(P<0.01),双侧卵巢体积明显缩小(P<0.01).血清LH、FSH、T水平和LH/FSH明显下降(P<0.01).FIN水平明显下降(P<0.01),IR也有相应降低(P<0.01),空腹血糖(FBG)和胰岛素敏感性指数(ISI)无明显改变(P>0.05).达英-35有很强的抗雄作用,明显改善了PCOS患者的内分泌状况和临床症状. 相似文献
96.
目的探讨三氧化二砷(As2O3)注射液单药连续区域动脉灌注化疗原发性肝癌的临床疗效。方法55例手术不能切除的非晚期原发性肝癌患者,随机分为两组:(1)As2O3治疗组26例:患者采用经股动脉肝动脉碘油栓塞后埋置皮下化疗泵,予以连续区域灌注As2O3化疗,20mg/d,每天1次,共7d,间隔4周重复,共5疗程。(2)对照组29例:采用经股动脉肝动脉栓塞化疗(TACE),2次TACE15例,3次TACE14例。结果As2O3治疗组总有效率为34.6%(9/26)、肿瘤复发率为15.4%(4/26)、1年生存率为80.7%(21/26);TACE组分别是31.0%(9/29)、37.9%(11/29)、51.7%(15/29)。统计学分析表明,两组的总有效率差异无统计学意义,P〉0.05;肿瘤复发率和1年生存率差异有统计学意义,P〈0.05。As2O3治疗组较对照组不良反应轻微,未见不可逆不良反应。结论经股动脉肝动脉碘油栓塞后埋置皮下化疗泵予以连续区域灌注As2O3化疗用于治疗原发性肝癌不良反应轻微、疗效确切,具有一定的临床应用前景。 相似文献
97.
The effects of co-culture with human fibroblasts on human embryo development in vitro and implantation 总被引:5,自引:0,他引:5
Wetzels AM; Bastiaans BA; Hendriks JC; Goverde HJ; Punt-van der Zalm AP; Verbeet JG; Braat DD 《Human reproduction (Oxford, England)》1998,13(5):1325-1330
In a human in-vitro fertilization (IVF) programme, the effect of co-
culture of embryos with human fibroblasts was evaluated with respect to
pregnancy rate and embryo development. Patients were included in the study
after giving informed written consent. The IVF treatments were randomly
assigned by stratification of both age (<36 versus > or =36 years)
and previous IVF attempts (yes versus no). After fertilization was
established, the zygotes were transferred to a 4-well dish with or without
fibroblasts and cultured for 2 days. On the third day after ovum pick-up
(OPU), cell number and quality [5 (good) to 1 (poor)] of the embryos were
scored and a maximum of three embryos was transferred. Supernumerary
embryos of good quality were cryopreserved. The design of this study was a
group sequential trial with the objective of detecting differences between
pregnancy rates following IVF with conventional incubation or incubation in
co-culture with fibroblasts. This design included one evaluation at
half-way data collection. In the study, 148 patients had an OPU, of whom 77
were allocated to the co-culture group. There was no statistically
significant difference in pregnancy rate, cell number and embryo quality
between the two groups. The ongoing pregnancy rate per embryo transfer was
27% in co-culture and 30% in the conventional culture group. The
implantation rates per transferred embryo were 17 and 18% respectively.
Using a multivariate logistic regression model for the probability of
ongoing pregnancies, the odds ratio of co-culture, adjusted for age and
previous IVF attempts, was not statistically significant. In conclusion,
co-culture with human fibroblasts does not contribute to an improvement of
embryo quality nor to a higher pregnancy rate after IVF in an unselected
group of patients.
相似文献
98.
Hydrosalpinges adversely affect markers of endometrial receptivity 总被引:22,自引:10,他引:22
Meyer WR; Castelbaum AJ; Somkuti S; Sagoskin AW; Doyle M; Harris JE; Lessey BA 《Human reproduction (Oxford, England)》1997,12(7):1393-1398
While in-vitro fertilization (IVF) was initially developed in women with
tubal factor infertility, recent clinical studies have suggested that the
presence of hydrosalpinges lowers implantation and pregnancy rates. We
postulated that these hydrosalpinges cause impaired endometrial
receptivity. A total of 103 women with hydrosalpinges were prospectively
evaluated, and compared with 55 infertile and 44 fertile controls. All
women had endometrial biopsies during the window of implantation, analysed
by conventional histological criteria, and also stained for three integrin
markers of endometrial receptivity (alpha1beta1, alpha4beta1 and alpha
vbeta3). Women with hydrosalpinges (cases) expressed significantly less of
the alpha vbeta3 integrin compared with controls. There was no difference
in expression of alpha1beta1 or alpha4beta1 among groups. A significantly
greater number of cases had out of phase histology and missing alpha vbeta3
(type I defects) and absent integrin expression despite normal histological
maturation (type II) defects, compared with controls. Of 20 women with
impaired endometrial receptivity who were also biopsied after hydrosalpinx
surgery, 70% demonstrated increased alpha vbeta3 expression. Seventy-seven
percent of type I and 57% of type II defects were corrected
postoperatively. Using markers of endometrial receptivity, this study
demonstrates that inflammatory hydrosalpinges have an adverse effect on
endometrial receptivity, which in some cases may be overcome by surgical
treatment of the hydrosalpinx.
相似文献
99.
100.
Sequence comparison of human and yeast telomeres identifies structurally distinct subtelomeric domains 总被引:6,自引:2,他引:6
Flint J; Bates GP; Clark K; Dorman A; Willingham D; Roe BA; Micklem G; Higgs DR; Louis EJ 《Human molecular genetics》1997,6(8):1305-1313
We have sequenced and compared DNA from the ends of three human
chromosomes: 4p, 16p and 22q. In all cases the pro-terminal regions are
subdivided by degenerate (TTAGGG)n repeats into distal and proximal sub-
domains with entirely different patterns of homology to other chromosome
ends. The distal regions contain numerous, short (<2 kb) segments of
interrupted homology to many other human telomeric regions. The proximal
regions show much longer (approximately 10-40 kb) uninterrupted homology to
a few chromosome ends. A comparison of all yeast subtelomeric regions
indicates that they too are subdivided by degenerate TTAGGG repeats into
distal and proximal sub-domains with similarly different patterns of
identity to other non-homologous chromosome ends. Sequence comparisons
indicate that the distal and proximal sub-domains do not interact with each
other and that they interact quite differently with the corresponding
regions on other, non- homologous, chromosomes. These findings suggest that
the degenerate TTAGGG repeats identify a previously unrecognized,
evolutionarily conserved boundary between remarkably different subtelomeric
domains.
相似文献