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排序方式: 共有556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
  相似文献   
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   
5.
Cellular inflammatory responses in human allergic skin reactions   总被引:2,自引:0,他引:2  
To define better the role of inflammation in the response to pollen antigens, we have used our skin chamber model to study inflammatory cells recovered from the sites of ongoing allergic reactions. In 15 atopic subjects, paired skin blister sites were simultaneously challenged with ragweed- or grass-pollen antigen or buffer for 5 hours. There were 10 times as many cells recovered at antigen (20.7 X 10(5)) than at buffer (2.0 X 10(5)) sites, p less than 0.005; greater than 97% of the cells recovered were neutrophils. The number of cells recovered at the antigen sites correlated with the total amount of histamine released (r = 0.57; p less than 0.05) but not with the extinction dilution skin test reactivity nor with the intensity of the late cutaneous allergic response measured 6 hours after the injection of antigen. Phase-contrast microscopic examination of the cells recovered from the antigen sites demonstrated that 82% to 95% were polarized compared to 0% to 1.5% of autologous blood neutrophils obtained simultaneously from the peripheral blood. Antigen site cells were as capable of serum-dependent phagocytosis as peripheral blood neutrophils. There was no significant difference in the migratory response to buffer, the chemoattractant N-formyl-methionyl-leucyl-phenylalanine, or leukotriene B4, but there was a significantly decreased response to platelet-activating factor when the cells recovered from antigen sites were compared to autologous blood neutrophils.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
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7.
Pregnancies in an 18-Year Follow-up after Biliopancreatic Diversion   总被引:4,自引:0,他引:4  
Background: 239 pregnancies occurred in 1136 women who had undergone biliopancreatic diversion (BPD). Methods: There were 73 abortions, and 14 pregnancies are presently in their course. The 152 term pregnancies (six twins) occurred in 129 women 2-173 months (mean 42.7) after BPD. Mean age and current excess weight were 31.4 years (20-42) and 29.1% (-6.9-78.2), and mean excess weight loss was 72.9% (30.4-110.5). Results: Mean weight gain during pregnancy was 6.2 kg (-21-25). In 32 patients (21%), parenteral nutritional support was needed. In all the other patients (79%), the usual supplementations were given. Of the newborns, 122 were delivered at term (84.7%) with a mean weight of 2842.4 g (1760-4600 g) and a mean length of 48.5 cm (43-59 cm), while the 22 preterm babies (15.3%) weighed 2151.1 g (1400-3850 g) and had a length of 44.6 cm (33-56 cm). Forty infants (27.8%) were small for gestational age but 17 of them weighed more than 2500 g. Eleven twins (one abortion at 26th week) were also delivered, with a mean weight of 2088.6 g (1200-3100 g) and a mean length of 45.6 cm (35-50 cm). Delivery was spontaneous in 85 instances (56%), while vacuum extractor was used in one, and 66 cesarean sections were performed. There were two birth malformations, one infant died after surgery for meconium obstruction and two died from unknown causes. Of the 129 women, 35 had been infertile before BPD. Conclusions: Disappearance of infertility and decrease of pregnancy risk are to be considered among the beneficial effects of weight reduction following BPD.  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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