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排序方式: 共有608条查询结果,搜索用时 15 毫秒
1.
Sonoelasticity imaging of prostate cancer: in vitro results   总被引:2,自引:0,他引:2  
  相似文献   
2.
Screening for early ovarian cancer   总被引:5,自引:0,他引:5  
Taylor  KJ; Schwartz  PE 《Radiology》1994,192(1):1
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3.
Tumor vascular signals in renal masses: detection with Doppler US   总被引:3,自引:0,他引:3  
Ramos  IM; Taylor  KJ; Kier  R; Burns  PN; Snower  DP; Carter  D 《Radiology》1988,168(3):633-637
The vascularity of 49 renal masses (26 malignant and 23 benign lesions) was investigated with duplex Doppler ultrasound. Doppler signals obtained at the margins of renal masses were defined as "tumor signals" when the Doppler-shifted frequency of the lesion exceeded the frequency shift in the ipsilateral main renal artery. These exceeded 2.5 kHz with a 3-MHz insonating frequency. Among the 26 renal masses that subsequently proved to be malignant, tumor signals were obtained in 15 of 18 (83%) untreated renal cell carcinomas, in three of four Wilms tumors, and in two patients with metastases to the kidney, but not in the one patient with lymphoma. None of the 23 benign renal masses demonstrated tumor signals. Tumor vascularity in malignant lesions gives rise to abnormal, high-velocity, Doppler-shifted signals that can help in the differential diagnosis of renal masses.  相似文献   
4.
In human in-vitro fertilization (IVF)-embryo transfer, the in-vitro culture environment differs from in-vivo conditions in that the oxygen concentration is higher, and in such conditions the mouse embryos show a higher concentration of reactive oxygen species (ROS) in simple culture media. ROS are believed to cause damage to cell membranes and DNA fragmentation in somatic cells. This study was conducted to ascertain the level of H2O2 concentration within embryos and the morphological features of cell damage induced by H2O2. A total of 62 human oocytes and embryos (31 fragmented, 15 non-fragmented embryos, 16 unfertilized oocytes) was obtained from the IVF-embryo transfer programme. The relative intensity of H2O2 concentrations within embryos was measured using 2',7'-dichlorodihydrofluorescein diacetate by Quanti cell 500 fluorescence imaging and DNA fragmentation was observed with transmission electron microscopy and an in-situ apoptosis detection kit. The H2O2 concentrations were significantly higher in fragmented embryos (72.21 +/- 9.62, mean +/- SEM) compared to non-fragmented embryos (31.30 +/- 3.50, P < 0.05) and unfertilized oocytes (30.75 +/- 2.67, P < 0.05). Apoptosis was observed only in fragmented embryos, and was absent in non-fragmented embryos. Electron microscopic findings confirmed apoptotic bodies and cytoplasmic condensation in the fragmented blastomeres. We conclude that there is a direct relationship between increased H2O2 concentration and apoptosis, and that further studies should be undertaken to confirm these findings.   相似文献   
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PURPOSE: Although the exact etiology of interstitial cystitis remains elusive, bladder inflammation appears to be common in many patients. The National Institutes of Health (NIH) have established diagnostic criteria for interstitial cystitis based on the presence of irritative voiding symptoms in the absence of other identifiable pathology. Cystoscopic examination with hydrodistention performed in patients under anesthesia is part of the NIH diagnostic criteria. We determine if the severity of cystoscopic findings correlated with histological evidence of inflammation in patients with suspected interstitial cystitis. MATERIALS AND METHODS: A total of 69 patients who met NIH symptom criteria for interstitial cystitis and underwent cystoscopy, hydrodistention and bladder biopsy under anesthesia were reviewed. There were 2 investigators blinded to the histological data who independently reviewed operative reports. A urological pathologist blinded to the clinical data reviewed biopsies for inflammation severity. Cystoscopic and histological findings were then converted to a numeric scale. Numeric data were analyzed using the Pearson correlation coefficient. RESULTS: Cystoscopic examination revealed no evidence of interstitial cystitis in 6 patients (9%), mild changes in 27 (39%), moderate changes in 23 (33%) and severe changes in 13 (19%). Histological examination revealed no inflammation in 21 patients (30%), mild inflammation in 28 (41%), moderate inflammation in 11 (16%) and severe inflammation in 9 (13%). Histological scores correlated poorly with total and scaled cystoscopic severity scores (r = 0.295 and 0.349, respectively). CONCLUSIONS: Severity of cystoscopic findings observed during hydrodistention with anesthesia does not appear to correlate with the degree of inflammation identified histologically in patients with suspected interstitial cystitis.  相似文献   
8.
Should calcaneal fractures be treated surgically? A meta-analysis   总被引:8,自引:0,他引:8  
A MEDLINE search from 1980 through 1996 revealed 1845 articles dealing with calcaneal fractures. Six of these articles that compared operative versus nonoperative treatment for displaced calcaneal fractures met the minimum criteria for inclusion in a meta-analysis. A statistical summary of information across the six articles revealed a trend for surgically treated patients to be more likely to return to the same type of work as compared with nonoperatively treated individuals. There also was a trend for nonoperatively treated patients to have a higher risk of experiencing severe foot pain than did operatively treated patients. Unfortunately, none of the other outcomes could be summarized formally across studies using statistical techniques because of variability in reporting across studies. Although the tendency was always for operatively treated patients to have better outcomes (reaching statistical significance in some of the articles), the strength of evidence to recommend operative treatment for displaced intraarticular calcaneal fractures remains weak. A large prospective randomized controlled trial should be able to answer this question.  相似文献   
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Andreesen  R; Osterholz  J; Lohr  GW; Bross  KJ 《Blood》1984,63(6):1299-1302
A Hodgkin cell-specific antigen detected by the monoclonal antibody Ki- 1 was found on T helper lymphocytes after activation by autologous and allogeneic stimulator cells. About 50% of lymphoblasts generated by auto- and alloactivation reacted with the antibody. In contrast, only less than 6% of lymphoblasts stimulated with Con-A, phytohemagglutinin (PHA), or protein A, and none of lymphoblasts activated by oxidative mitogenesis, expressed this antigen. Among several permanent cell lines tested, the K562, MOLT-4, HL-60, and EBV transformed B lymphoblastoid cells reacted with the Ki-1 antibody. The results may indicate possible relationships between the autoreactive subset of T lymphocytes and the pathogenesis of Hodgkin's disease.  相似文献   
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