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排序方式: 共有653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
2.
J A Webb P E Baer R J Mclaughlin R S McKelvey C D Caid 《Journal of the American Academy of Child and Adolescent Psychiatry》1991,30(4):563-568
This study examined the relationship between risk factors and initiation of alcohol use over a 15-month period among a cohort of 7th graders who were abstainers at the time of initial testing. The relationship between risk factors and alcohol use was examined using a discriminant function analysis. At the univariate level, rejection of parental authority, deviant behavior, and sensation seeking were statistically significant. The discriminant function retained only three of the risk factors: rejection of parental authority, deviant behavior, and religious commitment. Implications for school-based prevention programs are discussed, particularly the need to target primary prevention programs based upon adolescents' risk. 相似文献
3.
K L O'Neill V J McKelvey M Hoper H Monteverde G W Odling-Smee H Logan W P Abram P G McKenna 《Medical laboratory sciences》1992,49(4):244-247
Thymidine kinase (TK) exists in two forms, TK1 and TK2. TK levels and oestrogen receptor status (OR) were measured in tumours from 86 patients with operable breast cancer and the patients were monitored for recurrence over 24 months. During the monitored period, 13 patients showed recurrence. These patients also exhibited higher total TK levels per mg tumour (P < 0.01) and higher TK1 levels (P < 0.001) than those who did not show recurrence. TK1 levels relative to TK2 were significantly higher (P < 0.05) in OR-negative tumours (n = 29) than in OR-positive tumours (n = 57). OR-negative (n = 9) and OR-positive (n = 4) patients who recurred had significantly higher TK1 levels relative to TK2 than did those who not recur (n = 20 and n = 53, respectively). These preliminary results indicate that breast tumour TK levels may have value in determining prognosis. 相似文献
4.
Screening for early ovarian cancer 总被引:5,自引:0,他引:5
5.
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
6.
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
7.
8.
Pathways to care for alcohol use disorders 总被引:1,自引:0,他引:1
9.
BACKGROUND: The insertion and subsequent removal of chest tubes are frequently performed procedures. We hypothesize that routine chest radiographs obtained after chest tube removal to confirm the absence of any post-procedure complications have little impact on clinical management. MATERIALS AND METHODS: A 5-year retrospective study of 73 patients with tube thoracotomies was performed in a level II trauma center's intensive care unit. Patients were identified from billing records for chest tube placement. Medical records and official chest x-ray film reports, both before and after removal, were reviewed, and demographic data were collected. RESULTS: Of the 73 patients examined, only 8 had postprocedure reports that differed from the preprocedure reports. Two of these 8 patients required reinsertion of a chest tube to treat the recurrence of a significant pneumothorax. However, the decision to reinsert the chest tube was based on the patient's clinical appearance rather than on the x-ray findings. CONCLUSION: Chest radiography following the removal of chest tubes should not be a routinely performed procedure, but should preferably be based on the good clinical judgement and discrimination of the surgeon. 相似文献
10.