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排序方式: 共有902条查询结果,搜索用时 15 毫秒
11.
Interobserver variability in determining MIB-1 labeling indices in oligodendrogliomas 总被引:1,自引:0,他引:1
Prayson RA Castilla EA Hembury TA Liu W Noga CM Prok AL 《Annals of diagnostic pathology》2003,7(1):9-13
Several studies have shown that MIB-1 labeling indices correlate well with tumor grade and prognosis in a variety of tumor types. Several factors are responsible for some degree of variability in the determination of labeling indices. Interobserver variability is one of the factors often cited as responsible for this variability. A slide from each of 30 oligodendrogliomas, stained with MIB-1 antibody, was distributed to six pathologists. The same set of slides was reviewed by each individual. Each pathologist was instructed to determine a MIB-1 labeling index by evaluating 1,000 tumor cell nuclei from the area of the slide with the most staining. The labeling index record reflected a percentage of positive-staining tumor cells. Interobserver agreement was compared. MIB-1 labeling indices ranged from 0 to 45.7. Overall agreement was good (> or =0.75) with a concordance coefficient of 0.832 (confidence interval, 0.700 to 0.909). Variability was greater among tumors with higher labeling indices as compared with tumors with labeling indices closer to 0. The overall agreement of MIB-1 labeling indices, while not perfect, was good. The generally minor variability among observers may be related to differences in the area of the slide evaluated and in differing lower thresholds for interpreting positivity. Further improvement of concordance may theoretically be attainable by further training and discussion among observers. 相似文献
12.
Congenital malformations in twins: an international study 总被引:9,自引:0,他引:9
Mastroiacovo P Castilla EE Arpino C Botting B Cocchi G Goujard J Marinacci C Merlob P Métneki J Mutchinick O Ritvanen A Rosano A 《American journal of medical genetics》1999,83(2):117-124
Data provided by nine registries based in European and Latin America countries were analyzed to assess whether there is an excess of malformations in twins compared to singletons. Specific congenital malformations were coded according to the ninth revision of the International Classification of Diseases (ICD). Malformation rates and rate ratios (RR) for twins compared to singletons were calculated for each registry, and the homogeneity of the RRs was tested using the test of Breslow and Day. If departure from homogeneity in the different registries was not significant, registry-adjusted RRs with 95% confidence intervals were calculated. Overall, among 260,865 twins, 5,572 malformations were reported. A total of 101 different types of malformations or groups of defects was identified, and a homogeneous estimate of the RRs among registries was found for 91.1% of the malformations. Thirty-nine of the 92 malformations with homogeneous estimates of RRs were more common in twins than in singletons. For the remaining nine malformations, heterogeneous estimates of RRs were obtained. This study confirms the majority of already known associations and further identifies previously unreported malformations associated with twins. In conclusion, there is an excess of malformations in twins compared with singletons, and all anatomical sites are involved. The number of specific malformations associated with twins is higher than that previously reported in smaller studies. 相似文献
13.
Hugues JN Soussis J Calderon I Balasch J Anderson RA Romeu A;Recombinant LH Study Group 《Human reproduction (Oxford, England)》2005,20(3):629-635
BACKGROUND: In anovulatory women undergoing ovulation induction, addition of recombinant human LH (rLH) to FSH treatment may promote the dominance of a leading follicle when administered in the late follicular phase. The objective of this study was to find the optimal dose of rLH that can maintain the growth of a dominant follicle, whilst causing atresia of secondary follicles. METHODS: Women with infertility due to anovulation and over-responding to FSH treatment were randomized to receive, in addition to 37.5 IU recombinant human FSH (rFSH), either placebo or different doses of rLH (6.8, 13.6, 30 or 60 microg) daily for a maximum of 7 days. The primary efficacy endpoint was the proportion of patients who had exactly one follicle > or = 16 mm on hCG day. RESULTS: Among 153 enrolled patients, the five treatment groups were similar in terms of baseline characteristics. The proportion of patients with exactly one follicle > or = 16 mm ranged from 13.3% in the placebo group to 32.1% in the 30 microg rLH group (P = 0.048). The pregnancy rate ranged from 10.3% in the 60 microg group to 28.6% in the 30 microg rLH group. Adverse events were similar between groups. CONCLUSIONS: In patients over-responding to FSH during ovulation induction, doses of up to 30 microg rLH/day appear to increase the proportion of patients developing a single dominant follicle (> or = 16 mm). Our data support the 'LH ceiling' concept whereby addition of rLH is able to control development of the follicular cohort. 相似文献
14.
Rosano A Smithells D Cacciani L Botting B Castilla E Cornel M Erickson D Goujard J Irgens L Merlob P Robert E Siffel C Stoll C Sumiyoshi Y 《Journal of epidemiology and community health》1999,53(10):630-635
OBJECTIVE: To examine time trends in neural tube defects (NTD) prevalence from 1987 to 1996 in relation to the primary prevention policies for folic acid supplementation strategies in different countries. DESIGN: Retrospective time trends analysis of NTD prevalence. SETTING: 11 birth defect registries of congenital malformations participating in the International Clearinghouse for Birth Defects Monitoring System, in the period from 1 July 1987 to 30 June 1996. SUBJECTS: 8207 live births, stillbirths and terminated pregnancies affected by anencephaly or spina bifida registered by the 11 participating centres 1987-1996. OUTCOME MEASURES: Prevalence rate ratios based on the annual rates, using the Poisson regression model. RESULTS: During the study period a significant fall in prevalence rates for all NTD is present in Atlanta (USA), England and Wales, Hungary and Japan, and a significant rise in Norway and South America. After adjusting for the secular trends observed in the earlier years of the study, no significant trend can be attributed to preventive strategies. Data on NTD prevalence are supplemented with information on folate awareness among some of the populations studied. CONCLUSION: There is no evidence that, up to the middle of 1996, any change in time trend was attributable to the introduction of national folate supplementation policies. The possible effectiveness of folate supplementation policies for the reduction of NTD clearly needs to be tried and studied for several more years. Considering that in the Western world about 50% of pregnancies are unplanned, a policy that rests on action taken before conception can only have limited success. Strategies based on food enrichment, such as was introduced in the USA from the beginning of 1998, may prove to be more successful. 相似文献
15.
J Castilla Catalán C Moreno Iribas E Eguino Sasiain 《Gaceta sanitaria / S.E.S.P.A.S》1992,6(31):153-156
In order to explore the validity of official infant mortality statistics, the number of infant deaths registered in the cohort of live births and resident in Navarra (Spain) from 1985 to 1989, according to data supplied by the Department of Statistics of Navarra, has been compared with that obtained in a retrospective search into the information of the hospitals. Among 24,383 live births of the cohort, 291 were certified as infant deaths. An over-register of 13 cases (4.5%) and an under-register of 26 cases (8.9%) was detected. By excluding those live births with less than six months of gestation, as done by the National Institute of Statistics, the validity is altered, because apart from the errors mentioned, one must add those resulting from the incorrect filling-in of the "number of weeks pregnant"= variable. When correcting these deficiencies, the final statistics (Infant Mortality Risk = 11.17 per 1000 live births) did not differ much from the official figures (IMR = 11.48 per 1000 live births). 相似文献
16.
Harley B Messinger Egilius LH Spierings Arnaud JP Vincent John Lebbink 《Cephalalgia : an international journal of headache》1991,11(1):13-18
In two headache questionnaire surveys we inquired about the occurrence of headache in the mothers, fathers, siblings and children of the respondents. In total, 633 people completed valid questionnaires, 260 in the first survey and 373 in the second. The hypothesis was that familial headache occurrence would be positively associated with headache frequency. In each survey, the regression of headache frequency on the number of parents having headache was highly significant. Neither sex nor the sibling and children variables were significant predictors. In the cross-tabulations of the parental occurrence of headache with headache frequency we saw a clear "break-point" between the "no headache" and the headache frequency categories studied. For the final analyses the dichotomy "headache/no headache" was related in fourfold tables to headache occurrence in the father and the mother separately, and to the number of headache parents. The positive associations were not simply due to the large number of migraine cases since they remained after removing the migraineurs. 相似文献
17.
Early stage nasopharyngeal carcinoma: radiotherapy dose and time factors in tumor control 总被引:1,自引:0,他引:1
Chang JT; See LC; Liao CT; Chen LH; Leung WM; Chen SW; Chen WC 《Japanese journal of clinical oncology》1998,28(3):207-213
OBJECTIVE: To evaluate radiotherapy dose and length of treatment in the
control of early stage nasopharyngeal carcinoma (NPC) treated with a
combination of external radiotherapy and brachytherapy, MATERIALS &
METHODS: We reviewed the records of 133 patients with early stage
nasopharyngeal carcinoma (stage I or II, AJC/UICC staging system) who
received definitive radiotherapy in Chang Gung Memorial Hospital from 1979
to 1991. The median follow-up time was 7.1 years with a minimum of 2 years.
All patients were treated with megavoltage external radiotherapy to the
nasopharynx area (63-72 Gy) followed by high dose rate intracavitary
brachytherapy (5-16.5 Gy in one to three fractions, spaced 1-2 weeks
apart). The median total dose and time of irradiation was 75 Gy (69.8-81.4
Gy) and 11.6 weeks (7.8-20 weeks) respectively. Survival analysis was used
to examine the effect of several variables on prognosis. RESULTS: The
5-year rates were 86.4% for local control, 84.7% for disease free survival,
88.5% for actuarial survival and 84.2% for overall survival. The treatment
group (combination of time and dose of irradiation) was the most important
prognostic factor according to Cox's proportional hazard model. Patients
receiving radiation at a total dose of < or = 75 Gy completed in < 12
weeks showed the best prognosis. CONCLUSION: Treatment time and total
treatment dose are both important factors in treating early stage NPC.
Decreasing the total radiation time to < 12 weeks and not exceeding a
radiation dose of 75 Gy gave the best results.
相似文献
18.
Jose R. Gonzalez‐Porras Fernando Escalante Emilia Pardal Magdalena Sierra Luis J. Garcia‐Frade Santiago Redondo Maryam Arefi Carlos Aguilar Fernando Ortega Erik de Cabo Rosa M. Fisac Oscar Sanz Carmen Esteban Ignacio Alberca Mercedes Sanchez‐Barba Maria T. Santos Abel Fernandez Tomas J. Gonzalez‐Lopez representing the Grupo de Trombosis y Hemostasia de Castilla y León 《European journal of haematology》2013,91(3):236-241
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