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排序方式: 共有468条查询结果,搜索用时 31 毫秒
1.
Sonoelasticity imaging of prostate cancer: in vitro results 总被引:2,自引:0,他引:2
2.
Screening for early ovarian cancer 总被引:5,自引:0,他引:5
3.
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.
Detection of reactive oxygen species (ROS) and apoptosis in human fragmented embryos 总被引:8,自引:2,他引:8
Yang HW; Hwang KJ; Kwon HC; Kim HS; Choi KW; Oh KS 《Human reproduction (Oxford, England)》1998,13(4):998-1002
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.
6.
7.
Pathways to care for alcohol use disorders 总被引:1,自引:0,他引:1
8.
CT features of gastric lymphoma 总被引:3,自引:0,他引:3
The gastrointestinal tract is the most frequent site of extranodal involvement by lymphoma and stomach is the most frequently
involved. The incidence of gastric lymphoma appears to be rising as that of adenocarcinoma is declining. It produces a spectrum
of radiologic appearances and its distinction from adenocarcinoma is difficult since their findings frequently overlap. The
aim of this article is to present pictorially a spectrum of CT findings of the gastric lymphoma.
Received: 11 August 1998; Revision received: 26 March 1999; Accepted: 30 June 1999 相似文献
9.
A rare case of primary seminoma in the retroperitoneum is described. Ultrasound detected a huge hypoechoic mass and correlative
computed tomography showed a midline, homogeneous, lobulated mass in a man who presented for anuria.
Received: 1 April 1999; Revised: 28 June 1999; Accepted: 27 July 1999 相似文献
10.
Tsimoyiannis EC Siakas P Glantzounis G Tsimoyiannis JC Karayianni M Gossios KJ 《International surgery》2000,85(3):234-236
BACKGROUND: Knowledge on the viability of hydatid cysts of the liver during operation is important to the surgeon may dictate the peri-operative therapeutic manoeuvre undertaken. PATIENTS AND METHODS: A prospective study was performed on 23 patients with 28 hydatid cysts of the liver to assess whether intracystic pressure (ICP) could predict viability of protoscoleces. All patients received albendazole (10 mg/kg body weight/day) for 5 days pre-operatively. The ICP was measured from the apex of the cyst, after laparotomy, using a 16-G needle connected to a water manometer. After manometry, the cyst contents were aspirated and the viability of protoscoleces assessed by their flame cell activity, motility and ability to exclude 5% aqueous eosin. RESULTS: The median ICP was 54 +/- 21 cmH2O for 17 viable cysts and zero for 8 non-viable cysts, while 1 additional non-viable cyst and 2 sterilized cysts had high ICP (sensitivity, 100%; specificity, 72%; accuracy, 89%). The median diameter of the viable cysts was 9.3 +/- 3.5 cm and the non-viable cysts 10.7 +/- 2.6 cm. In the right lobe were located 12 viable and 8 non-viable cysts and in the left lobe, 5 viable and 3 non-viable cysts. No significant difference in diameter or ICP were noted between the hepatic lobes. CONCLUSIONS: These findings suggest that the measurement of ICP is a simple, cheap and reliable method for assessment of the viability of hydatid cysts of the liver. 相似文献