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排序方式: 共有637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.
The influence of team experience on outcomes of endovascular stenting of abdominal aortic aneurysms. 总被引:1,自引:0,他引:1
R J F Laheij C J van Marrewijk J Buth P L Harris 《European journal of vascular and endovascular surgery》2002,24(2):128-133
OBJECTIVE: To determine whether the experience of the specialist team was associated with adverse events following endovascular treatment of abdominal aortic aneurysms. METHODS: The EUROSTAR database is a voluntary registry of 2863 patients admitted to 93 hospitals in Europe with an abdominal aortic aneurysm treated with endovascular stenting. Mortality, rupture and the need for secondary interventions were the main outcomes. RESULTS: In patients who underwent endovascular stenting by the most experienced specialist teams the mortality rate was 40% lower than in those treated by the least experienced teams (adjusted hazard ratio 0.60, 95% confidence interval: 0.4-1.0; p = 0.05). Also patients treated by the most experienced specialist teams were 68% less likely to have adverse events necessitating a secondary intervention than those treated by the least experienced teams (adjusted hazard ratio 0.32, 95% confidence interval: 0.2-0.5; p < 0.001). The crude rupture rate was 0.1% among patients treated by the most experienced specialist teams and 0.8% among those treated by the least experienced teams (p = 0.74). CONCLUSIONS: Specialist teams with a high level of experience of endovascular abdominal aortic aneurysm stenting encounter lower mortality rates and fewer adverse events leading to secondary interventions. 相似文献
3.
Screening for early ovarian cancer 总被引:5,自引:0,他引:5
4.
Jean-Francois Légaré Ansar Hassan Karen J Buth John A Sullivan 《Journal of cardiothoracic surgery》2007,2(1):44-8
Background
While it is believed that total arterial grafting (TAG) for coronary artery bypass grafting (CABG) confers improved long-term outcomes when compared to conventional grafting with left internal mammary artery and saphenous vein grafts (LIMA+SVG), to date, this has not become the standard of care. In this study, we assessed the impact of TAG on medium-term outcomes after CABG. 相似文献5.
To define long-term results of modified human umbilical vein (MHUV) grafts a retrospective study was undertaken, and in addition the incidence of aneurysmal degeneration was investigated by Colour-Duplex scanning. From July 1979 until December 1986, 227 MHUV grafts were implanted in 181 patients (204 limbs). The operative indication was claudication in 110 limbs and ischaemic rest pain or gangrene in 94 limbs. The distal anastomosis was at the level of the popliteal artery in 167 limbs and at one of the crural arteries in 37 limbs. During the first month mortality was 3%. Primary and secondary patency rates were calculated for different subgroups. At 5 years the cumulative primary and secondary patency rates for femoro-popliteal grafts were 56 and 64% and for femoro-crural bypasses 19 and 21%. In the retrospective part of this analysis non-occlusive graft-failure occurred in 14 limbs (7%). This was due to infection (7 limbs), aneurysm-formation (4 limbs) or progressive footgangrene (3 limbs). Six of these limbs came to an amputation, however, no amputation was related to aneurysmal degeneration. The amputation-rate was significantly higher in the group with femoro-crural reconstructions as compared to the group with femoro-popliteal reconstructions (32 and 13% respectively; P less than 0.001). From these observations it becomes apparent that the use of MHUV-grafts as femoro-crural bypass is rarely justified. Aneurysmal changes as found by colour-Duplex scanning of 63 limbs with patent grafts at the time of this investigation were present in 23 grafts (37%). The mean internal diameter of the aneurysms was 12.6 mm (range 9.1 to 43.0 mm).(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
6.
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
7.
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
8.
9.
Pathways to care for alcohol use disorders 总被引:1,自引:0,他引:1
10.
Objective To explore the characteristics of arrhythmogenic right ventricular cardiomyopathy (ARVC). Methods Seven patients with arrhythmogenic right ventricular cardiomyopathy and 34 members of three families were studied. All patients and family members underwent history collection, clinical examination, electrocardiogram (ECG), two-dimensional echocardiography (2-DE) and a signal averaging electrocardiogram. Programmed ventricular stimulation was performed in five patients. Results All patients and family members had normal morphologic characteristics and normal function of the left ventricular by 2-DE. Fourteen persons had abnormal findings indicating ARVC. Five had enlargement of the right ventricular with diffused hypocontractility, eight had thin and systolic bulging in the focal anterior wall with hypokinesia and one had bulging of the inferior wall. Twenty-five persons (seven patients and 18 family members) had abnormal findings in ECG. Positive ventricular late potential was recorded in 13 persons (six patients). Two to three monomorphic ventricular tachycardia (VT) with left bundle branch block (LBBB) configurations were induced in five patients. Ventricular fibrillation was induced in two patients during the electrophysiologic study (EPS). Five patients had very high pacing threshold and/or ineffective pacing in one or many regions of the right ventricle. Two members of one family died suddenly. One member was a dwarf with ARVC. Spontaneous VT with a left bundle branch block (LBBB) configuration was recorded in five patients, polymorphic VT with extremely short coupling interval in one, and premature ventricular complexes with LBBB configuration in 12 (six patients). Conclusion Our familial study strongly suggests that ARVC may be a hereditary disease and it is helpful in the diagnosis and detection of ARVC. The most common manifestations were abnormal structure and function of the right ventricle and abnormal ECG of repolarization and ventricular arrhythmia which originates from the right ventricle. 相似文献