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排序方式: 共有504条查询结果,搜索用时 15 毫秒
1.
Jonathan E. Bishop Giles E. Santyr Frederick Kelcz Donald B. Plewes 《Journal of magnetic resonance imaging : JMRI》1997,7(4):716-723
The effect of keyhole data acquisition on quantitative analysis of dynamic MRI was examined. Experiments were performed retrospectively on raw data obtained from clinical dynamic contrast-enhanced breast imaging procedures. The effects of keyhole phase-encoding acquisition and type of reconstruction algorithm on the accuracy of derived quantitative parameters was assessed. Results indicate that the minimum keyhole size used should be restricted by the approximate minimum size of the expected lesions. Furthermore, reconstruction algorithms that offer improved image resolution do not circumvent this restriction. 相似文献
2.
进一步研究了抗三尖杉酯碱的HL-60细胞(HR20)抗细胞凋亡的机制及该抗性和抗药性的关系。结果表明,环孢菌素A(CsA)20,10μg·ml ̄(-1)诱导HL-60细胞发生凋亡,而阻断HR20细胞于G_1期,就不能诱导细胞发生凋亡。低浓度的CsA明显增加柔红霉素在HR20细胞内的积聚,其逆转抗药性作用与阻断细胞周期运行无关。CsA10μg·ml ̄(-1)处理HR20细胞,可引起50kDa的蛋白质高度磷酸化。结果提示:环孢菌素A阻断抗三尖杉酯碱的HL-60细胞于G_1期,而诱导敏感的HL-60细胞发生凋亡,其阻断作用与抗药性无关 相似文献
3.
Hydrolysis of peptides within lumen of small intestine 总被引:2,自引:0,他引:2
4.
Summary The relationships of VII and VIII cranial nerves and related arteries are reviewed in 26 preparations by microdissection techniques. These vessels may be grouped in large (AICA, PICA), medium (LA, SA, CSA, RPI) and small calibre (vasa nervorum, radicullar and medullar branches). The importance of these structures in acoustic neuroma surgery, vestibular neurectomy and cross-compression syndromes is discussed. Vascular loops and elongated arteries are normal structures present at birth.This work was supported by a grant from the AJ Roemmers Foundation 相似文献
5.
Differential pattern of DNA-aneuploidy in human malignancies 总被引:5,自引:0,他引:5
Th Büchner W Hiddemann B Wörmann B Kleinemeier J Schumann W Göhde J Ritter K.-M Müller DB von Bassewitz A Roessner E Grundmann 《Pathology, research and practice》1985,179(3):310-317
The differential pattern of DNA-aneuploidy, detected by flow cytometry (FCM) regarding its frequency, grade and multiclonality, was investigated and correlated to tumor type, malignancy grade, tumor stage and prognosis in a multi-institutional study at the University of Münster. High resolution measurements using admixed normal blood reference cells were undertaken in 2413 cases of 13 different malignant diseases and in 776 benign lesions or samples. The incidence of DNA-aneuploidy was highest in melanomas, carcinomas, testicular tumors, sarcomas (75%-95%) and myelomas (65%). Acute leukemias showed an intermediate DNA-aneuploidy rate of 40% with special subgroups represented by common ALL (44%), p less than 0.05) and myelomonocytic/monocytic AML (47%, p less than 0.01). The lowest DNA-aneuploidy-rate was found in basal cell skin carcinomas (19%) and congenital melanocytic nevi (9%). No case of DNA-aneuploidy was observed in the 776 benign lesions or samples.--DNA-indices giving the grade of DNA-aneuploidy with 1.0 for normal diploid G1/0 cells were found distributed predominantly between 1.0 and 2.0 in the solid tumors, except testicular tumors, clustering around a triploid maximum at 1.5. DNA-indices of myelomas and acute leukemias generally ranged below 1.25 with lower DNA-aneuploidy grades in AML than in ALL (p less than 0.01).--In melanomas the aneuploidy rate was higher (86%) in metastases than in the primary tumors (54%, p = 0.001).(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
6.
7.
Osteosarcomatosis 总被引:10,自引:0,他引:10
Hopper KD; Moser RP Jr; Haseman DB; Sweet DE; Madewell JE; Kransdorf MJ 《Radiology》1990,175(1):233-239
A review of the 690 cases of osteosarcoma in the radiographic file of the Armed Forces Institute of Pathology revealed 29 cases of "osteosarcomatosis" (multiple skeletal sites of osteosarcoma). Fifteen of these patients were 18 years old and under and manifested rapidly appearing, usually symmetric, sclerotic metaphyseal lesions. The remaining 14 patients were more than 18 years old and had fewer, asymmetric sclerotic lesions. In most patients (28 of 29), a radiographically dominant skeletal tumor was seen. Pulmonary metastases occurred in the majority of patients and were detected at the same time as the bone lesions. These 29 patients were studied with regard to demographic data and skeletal distribution and radiographic appearance of their lesions. As a result of the findings, a metastatic origin from a primary dominant osteosarcoma is favored over a multifocal origin as the basis for osteosarcomatosis. Osteosarcomatosis is more commonly encountered in the mature skeleton than has been previously recognized. 相似文献
8.
Richard Hart Chellapa Rajgopal Arthur Plewes John Sweeney Ward Davies Daryl Gray Brian Taylor 《Canadian journal of surgery》1996,39(6):457-462
Objective
To compare the efficacy of laparoscopic appendectomy (LA) and open appendectomy (OA) in the treatment of acute appendicitis.Design
A prospective randomized trial.Setting
A university teaching hospital.Patients
Eighty-one patients with a diagnosis of acute appendicitis were prospectively randomized to undergo either LA or OA. The two groups were matched for age and sex.Interventions
LA or OA.Main Outcome Measures
Number of days in hospital and time to full recovery.Results
The mean hospital stay for LA was 3.23 days compared with 3.03 days for OA (p < 0.001). The mean number of narcotic injections required for patients in the LA group was 4.05 compared with 5.58 for patients in the OA group (p < 0.001). The mean time to complete recovery for patients in the LA group was 9.0 days compared with 16.2 days for patients in the OA group (p < 0.001). The mean operative time for LA was 73.8 minutes compared with 45.0 minutes for OA (p < 0.001). Three patients in the LA group had intra-abdominal abscesses (p > 0.25). No significant difference in wound infection rates was demonstrated (p > 0.05). Similarly, pain scores at 7 and 28 days showed no significant difference (p > 0.05).Conclusions
With LA significantly fewer narcotic injections are required and there is a more rapid return to normal activities. LA takes longer to perform and was associated with three intra-abdominal abscesses. In cases of simple acute appendicitis the hospital stay for LA is significantly shorter. 相似文献9.
Influence of inhaled corticosteroids on growth: a pediatric endocrinologist''s perspective 总被引:7,自引:0,他引:7
DB Allen 《Acta paediatrica (Oslo, Norway : 1992)》1998,87(2):123-129
Given the increasing advocacy for the use of inhaled corticosteroids as a treatment of choice for persistent asthma, growing numbers of children are being exposed to the possible growth-suppressing effects of glucocorticoids. Recent evidence strongly suggests that, when consistently administered at moderate doses, inhaled corticosteroids (IC) are capable of slowing growth in children. Whether such growth suppression would persist and ultimately affect final adult height remains unknown. Therapeutic goals which aim for uninterrupted inflammatory disease control rather than periodic symptom control may increase the occurrence of growth failure in children treated with IC. In this article, current information about the mechanisms of growth suppression by glucocorticoids and the effects of IC on growth is reviewed, and recommendations for designing studies to investigate the effects of drugs on growth are presented. 相似文献
10.
van Kranen HJ; van Iersel PW; Rijnkels JM; Beems DB; Alink GM; van Kreijl CF 《Carcinogenesis》1998,19(9):1597-1601
The variation in colorectal cancer (CRC) incidence worldwide strongly
suggests a role for dietary influences. Based on epidemiological data,
protective effects of vegetables and fruit intake on CRC are widely
claimed, while other data indicate a possible increased CRC risk from
(higher) dietary fat intake. Therefore, we have investigated single and
interactive effects of dietary fat and a vegetable-fruit mixture (VFM) in
the ApcMin mouse, a mouse model for multiple intestinal neoplasia. In this
study, four different diets (A-D) were compared, which were either low in
fat (20% energy diets A/B) or high in fat (40% energy diets C/D). In
addition, 19.5% (wt/wt) of the carbohydrates in diets B and D were replaced
by a freeze-dried VFM. The diets were balanced so that they only differed
among each other in fat/carbohydrate content and the presence of specific
plant-constituents. Because the initiation of intestinal tumors in ApcMin
mice occurs relatively early in life, exposure to the diets was started in
utero. Without the addition of VFM, mice maintained at a high-fat diet did
not develop significantly higher numbers of small or large intestinal
adenomas than mice maintained at a low-fat diet. VFM added to a low-fat
diet significantly lowered multiplicity of small intestinal polyps (from
16.2 to 10.2/mouse, 15 animals/group), but not of colon tumors in male
ApcMin mice only. Strikingly, addition of VFM to female mice maintained on
a low-fat diet and to both sexes maintained on a high-fat diet
significantly enhanced intestinal polyp multiplicity (from 16.5 to 26.7
polyps/mouse). In conclusion, our results indicate that neither a lower fat
intake nor consumption of VFM included in a high-fat diet decreases the
development of polyps in mice genetically predisposed to intestinal tumor
development.
相似文献