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排序方式: 共有5821条查询结果,搜索用时 31 毫秒
41.
Pal L; Leykin L; Schifren JL; Isaacson KB; Chang YC; Nikruil N; Chen Z; Toth TL 《Human reproduction (Oxford, England)》1998,13(7):1837-1840
A case series of eight cycles of in-vitro fertilization (IVF) in five women
diagnosed with malignant disorders is presented. These patients chose to
defer definitive treatment for a chance for preservation of potential
fertility. The response of these patients to ovarian stimulation, and the
outcome, was compared with 17 IVF cycles in 12 age- matched patients with
isolated tubal infertility. An apparent adverse influence of malignant
disease on the quality and behaviour of oocytes was observed. Despite a
comparable total number of oocytes per cycle in the two groups, a
significantly reduced percentage of mature oocytes was retrieved per cycle
from patients with malignant diseases. The oocytes from patients with
malignant disorders were of a poorer quality and exhibited a significantly
impaired fertilization rate compared to the controls. We propose that
neoplastic processes, irrespective of the site or cell of origin, may have
a detrimental impact on the biology of oocytes, an effect akin to that seen
on spermatozoa in men with certain malignancies.
相似文献
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Mohan D Rolston R Pal R Swalsky PA Sasatomi E Lee RE Finkelstein SD 《Human pathology》2004,35(4):482-487
The genetic diagnosis of Gaucher disease by molecular methods is complicated by the existence of a highly homologous transcribed pseudogene (96% identity) that is found in close proximity to the true gene on chromosome 1q21. In addition, the pseudogene sequence can mimic disease-causing mutations in the true gene. Selective polymerase chain reaction (PCR) amplification of the true gene can be accomplished in extracted DNA from fresh-frozen samples by designing oligonucleotide primers to hybridize to defined regions that are not present in the pseudogene. This standard molecular approach, which entails amplification of relatively long segments of intact DNA, is not feasible in archival, paraffin-embedded, solid-tissue specimens in which the negative effects of chemical fixation result in DNA strand scission and breakdown of nucleic acid. A novel approach, specifically created for use with archival, fixative-treated tissue specimens, was developed for detection and characterization of common mutations of Gaucher disease. Three separate robust PCR reactions were formulated, 2 for selective amplification of portions of only the true gene exons 2 and 9, with a third reaction targeting exon 10, wherein both the true and pseudogene were coamplified. In the latter, DNA sequencing was used to determine the presence of true and pseudogene allele content in addition to identification of base sequence alterations. This method, requiring a single, 4-microm-thick histologic section, was successfully applied to archival paraffin block tissue specimens that had been in storage for up to 75 years. It was capable of accurately genotyping common Gaucher disease mutations as well as discovering a novel mutation and genetic polymorphism. We recommend our approach when only fixative-treated tis sue is available for molecular genotyping. 相似文献
44.
Genetic implications of double primary cancers of the colorectum and endometrium. 总被引:2,自引:0,他引:2
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T Pal T Flanders M Mitchell-Lehman A MacMillan J S Brunet S A Narod W D Foulkes 《Journal of medical genetics》1998,35(12):978-984
Hereditary non-polyposis colorectal cancer (HNPCC) is an autosomal dominant condition predisposing to cancers of the colorectum and endometrium. Endometrial cancer is the most commonly occurring extracolonic cancer in HNPCC. Estimates of the cumulative incidence of endometrial cancer in women with mutations in the HNPCC genes range from 22-43%. In order to determine how frequently double primary cancers of the colorectum and endometrium are the result of a hereditary factor, we conducted a registry based study in Ontario and Quebec, Canada. We obtained pedigrees on 80 women diagnosed with double primary cancers of the colorectum and endometrium at less than 70 years of age. Family histories of cancer were obtained for all first degree relatives of these women and cancer rates were compared with age standardised provincial incidence rates in order to estimate the relative risks. There was a total of 82 cancers observed in relatives below the age of 55, compared with 31.2 expected, giving a relative risk of 2.6 (95% confidence interval (CI) 2.1-3.3). The relative risk for colorectal cancer below 55 was 16.1 (95% CI 11.6-21.8). This risk decreased with increasing age of onset of cancers in probands. For probands with both colorectal and endometrial cancer diagnosed under the age of 55, the relative risk of colorectal cancer in relatives below the age of 55 was 30.5 (95% CI 18.8-46.6). Similar patterns were observed for endometrial and pancreatic cancer. There were non-significant increases in rates of cancer of the oesophagus, stomach, small intestine, and bladder. There was no increased risk of breast cancer. The risk of lung cancer was decreased, especially in older relatives. Our findings indicate the presence of a significant genetic component of cancer in women with double primary cancers of the colorectum and endometrium. 相似文献
45.
Mengoli C Cusinato R Biasolo MA Cesaro S Parolin C Palù G 《Journal of medical virology》2004,74(1):78-84
After bone marrow (BM) or solid-organ (SO) transplantation viremic Cytomegalovirus (CMV) infection is observed frequently. Quantitative assay of CMV in blood helps the management of this clinical condition. In the present report, 83 samples from 39 solid organ recipients, three CMV assays were compared simultaneously for the first time: the Nuclisens CMV pp67 assay (nucleic acid sequence-based amplification, NASBA), an "in-house" quantitative real-time PCR assay (TaqMan) for CMV DNA, and pp65 antigenemia. The relation between CMV DNA and pp65 antigenemia, the quantitative assays, was evaluated on a larger group including 251 blood samples from 118 solid organ recipients. Real-time PCR provided the best results; > or =130 CMV DNA copies/2 x 10(5) peripheral blood leukocytes (PBLs) predicted > or =1 pp65 antigen positive (Ag+) cell/2 x 10(5) PBLs. By taking pp65 antigenemia as the "gold standard," the sensitivity of CMV DNA quantitation and of the pp67 RNA assay were 0.95 and 0.20, respectively, while the corresponding specificity values were 0.50 and 0.93. When real-time PCR was considered as the "gold standard," the sensitivity and specificity of the pp65 antigenemia were 0.65 and 0.91, respectively. Among the three tests examined, the sensitivity of the pp67 RNA assay was the lowest. On the other hand, the pp67 RNA assay was highly specific and effective in pinpointing high viremia patients. The present report, by providing predictive values for all three diagnostic profiles, DNA load, antigenemia, and pp67RNA, is a contribution for validation of real-time PCR as a new standard for quantitative assessment of CMV viremia in clinical settings. 相似文献
46.
47.
48.
P Pauletto A Angelini G Vescovo G Scannapieco C Dario G Thiene A C Pessina C Dal Palù 《International journal of cardiology》1985,8(4):361-377
Both the reproducibility of the surface measurements of aortic atherosclerosis and the agreement between gross inspective and histologic changes were evaluated. Aortas from male broad breasted white turkeys were chosen because of the high incidence of spontaneous and typical atherosclerotic lesions in this animal strain. Ten male turkeys were killed at 33 weeks of age. The aortas were removed including the iliac bifurcation and stained with Sudan III. Each aorta was processed blindly by four pathologists and a computerized planimeter to determine normal areas, sudanophilic areas and areas covered by plaques. The analysis of variance showed significant differences among the four pathologists' measurements of sudanophilic areas (P less than 0.01) and areas covered by plaques (P less than 0.001). The coefficients of variation among the four determinations made by one pathologist on the same aorta were 3.6% for total aortic area; 10.08% for sudanophilic area; 47.6% for the area covered by plaques. On each aorta histology was performed at the level where all the four pathologists recorded the same findings at inspection, namely a normal area, a sudanophilic area, and an area covered by plaques. Important discrepancies occurred between findings at inspection and those of histologic examination: the ten areas classified as "normal" by all the four pathologists at inspection were shown at histologic examination to be normal in only two cases. In one case a musculo-elastic layer and in seven cases a fibro-elastic layer were found. The ten areas classified as "sudanophilic" by all the observers showed a fibro-elastic layer in five cases, a musculo-elastic layer in two cases and normal findings in three cases. The ten areas classified as "covered by plaques" displayed a typical atherosclerotic plaque in all cases but one. In conclusion, our data indicate that the reproducibility of gross inspective methods is low. Important discrepancies exist between findings at inspection and histologic examinations. The relevance of these findings remains to be established as far as the assessment of human atherosclerosis is concerned. 相似文献
49.
Computerized echography was used to assess left-ventricular dysfunction in 40 patients with dilatation cardiomyopathy (DCM). The so-called "floating" system was shown to be the most acceptable model for the correction of DCM-associated superposition. An original system was used for segment division by two- and four-chamber projections. Total left-ventricular hypokinesia and a significant reduction of the total ejection fraction (32.5 +/- 1.9%) were demonstrated. 相似文献
50.
Thomas Powles Michael B. Atkins Bernard Escudier Robert J. Motzer Brian I. Rini Lawrence Fong Richard W. Joseph Sumanta K. Pal Mario Sznol John Hainsworth Walter M. Stadler Thomas E. Hutson Alain Ravaud Sergio Bracarda Cristina Suarez Toni K. Choueiri James Reeves Allen Cohn David F. McDermott 《European urology》2021,79(5):665-673
BackgroundThe use of immune checkpoint inhibitors combined with vascular endothelial growth factor (VEGF)-targeted therapy as second-line treatment for metastatic clear cell renal cancer (mRCC) has not been evaluated prospectively.ObjectiveTo evaluate the efficacy and safety of atezolizumab + bevacizumab following disease progression on atezolizumab or sunitinib monotherapy in patients with mRCC.Design, setting, and participantsIMmotion150 was a multicenter, randomized, open-label, phase 2 study of patients with untreated mRCC. Patients randomized to the atezolizumab or sunitinib arm who had investigator-assessed progression as per RECIST 1.1 could be treated with second-line atezolizumab + bevacizumab.InterventionPatients received atezolizumab 1200 mg intravenously (IV) plus bevacizumab 15 mg/kg IV every 3 wk following disease progression on either atezolizumab or sunitinib monotherapy.Outcome measurements and statistical analysisThe secondary endpoints analyzed during the second-line part of IMmotion150 included objective response rate (ORR), progression-free survival (PFS), and safety. PFS was examined using Kaplan-Meier methods.Results and limitationsFifty-nine patients in the atezolizumab arm and 78 in the sunitinib arm were eligible, and 103 initiated second-line atezolizumab + bevacizumab (atezolizumab arm, n = 44; sunitinib arm, n = 59). ORR (95% confidence interval [CI]) was 27% (19–37%). The median PFS (95% CI) from the start of second line was 8.7 (5.6–13.7) mo. The median event follow-up duration was 19.4 (12.9–21.9) mo among the 25 patients without a PFS event. Eighty-six (83%) patients had treatment-related adverse events; 31 of 103 (30%) had grade 3/4 events. Limitations were the small sample size and selection for progressors.ConclusionsThe atezolizumab + bevacizumab combination had activity and was tolerable in patients with progression on atezolizumab or sunitinib. Further studies are needed to investigate sequencing strategies in mRCC.Patient summaryPatients with advanced kidney cancer whose disease had worsened during treatment with atezolizumab or sunitinib began second-line treatment with atezolizumab + bevacizumab. Tumors shrank in more than one-quarter of patients treated with this combination, and side effects were manageable. 相似文献