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171.
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Barbara H. Mason Ian M. Holdaway Stephen J. M. Skinner Ronald G. Kay 《Breast cancer research and treatment》1994,32(2):203-212
Summary The relationships between urinary 11-desoxy-17-oxo steroids (11-DOS), the ratio of 11-DOS to urinary 17-hydroxycorticosteroids (urinary discriminant ratio), plasma levels of the adrenal androgens dehydroepiandrosterone (DHA), DHA sulphate (DHAS), and 7-hydroxy DHA (7DHA), and tumour oestrogen receptor (ER) and progesterone receptor (PR) status were examined in pre, peri-, and postmenopausal women with breast cancer. Androgenic steroids and their metabolites decreased with age in women with breast cancer. In perimenopausal women there was a significant association of PR positive tumours and high androgen levels, whereas in postmenopausal women high androgen levels were associated with ER negative tumours. Survival was significantly related to plasma DHA level and tumour steroid receptor status. Thus, adrenal androgen levels below the group mean were associated with significantly decreased survival in women with postmenopausal receptor-positive tumours, and the association was particularly apparent in those who were axillary node negative. Since the number of patients studied was small these results should be regarded as provisional in nature. Nonetheless, the identification of this subgroup of node negative breast cancer women with reduced survival may be important when considering node negative patients for adjuvant therapy. 相似文献
173.
The risk of normal tissue damage imposes severe limitations on the radiotherapy of malignant tumours. The aim of this study was to examine the morphology of late radiation injury with special reference to microvasculature in the irradiated guinea pig spinal cord. Gamma radiation from a cobalt-60 source was used to irradiate the lumbar region of guinea pigs. A total dose of up to 94.5 Gy was given using 4.5 Gy fractions. Twenty such guinea pigs which survived more than 2 years post-irradiation were deeply anaesthetized and Mercox resin was perfused through the thoracic aorta. Ten minutes following perfusion, irradiated segments of the spinal cords were removed and either fixed in formalin for histology and morphometry or corroded in KOH for microvascular cast preparation. The latter were observed under the scanning electron microscope. All irradiated specimens showed multifocal white matter vacuolation. None of these spaces communicated with blood vessels. No such vacuolation was observed in grey matter. Glial cell counts in the irradiated white matter were reduced. Microvascular morphometry revealed 3.30% of the area was occupied by vasculature in the non-irradiated white matter. The corresponding value for irradiated white matter was 2.38% (p=0.003). No difference in the vascular area was noted in the non-irradiated grey matter (9.75%) and irradiated grey matter (10.36%; p=0.36) Microvascular casts did not reveal telangiectasia. However, irradiated specimens showed focal avascular regions. This was consistent with the light microscopic observation of focal degeneration and necrosis of irradiated white matter. These results suggest that late radiation injury in guinea pigs results primarily from damage to glial elements and the microvasculature is secondarily affected. 相似文献
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Laparoscopic management of benign solid and cystic lesions of the liver 总被引:20,自引:0,他引:20
Katkhouda N Hurwitz M Gugenheim J Mavor E Mason RJ Waldrep DJ Rivera RT Chandra M Campos GM Offerman S Trussler A Fabiani P Mouiel J 《Annals of surgery》1999,229(4):460-466
OBJECTIVE: The authors present their experience in the laparoscopic management of benign liver disease. The aim of the study is to analyze technical feasibility and evaluate immediate and long-term outcome. SUMMARY BACKGROUND DATA: Indications for the laparoscopic management of varied abdominal conditions have evolved. Although the minimally invasive treatment of liver cysts has been reported, the laparoscopic approach to other liver lesions remains undefined. METHODS: Between September 1990 and October 1997, 43 patients underwent laparoscopic liver surgery. There were two groups of benign lesions: cysts (n = 31) and solid tumors (n = 12). Indications were solitary giant liver cysts (n = 16), polycystic liver disease (n = 9), hydatid cyst (n = 6), focal nodular hyperplasia (n = 3), and adenoma (n = 9). Only solid tumors, hydatid cysts, and patients with polycystic disease and large dominant cysts located in anterior liver segments were included. All giant solitary liver cysts were considered for laparoscopy. Patients with cholangitis, cirrhosis, and significant cardiac disease were excluded. Data were collected prospectively. RESULTS: The procedures were completed laparoscopically in 40 patients. Median size was 4 cm for solid nodules and 14 cm for solitary liver cysts. Conversion occurred in three patients (7%), for bleeding (n = 2) and impingement of a solid tumor on the inferior vena cava (n = 1). The median operative time was 179 minutes. All solitary liver cysts were fenestrated in less than 1 hour. There were no deaths. Complications occurred in 6 cases (14.1%). Two hemorrhagic and two infectious complications were noted after management of hydatid cysts. There were no complications after resection of solid tumors. Three patients received transfusions (7%). The median length of stay was 4.7 days. Median follow-up was 30 months. There was no recurrence of solitary liver or hydatid cysts. One patient with polycystic disease had symptomatic recurrent cysts at 6 months requiring laparotomy. CONCLUSION: Laparoscopic liver surgery can be accomplished safely in selected patients with small benign solid tumors located in the anterior liver segments and giant solitary cysts. The laparoscopic management of polycystic liver disease should be reserved for patients with a limited number of large, anteriorly located cysts. Hydatid disease is best treated through an open approach. 相似文献
179.
Belmont PJ Shawen SB Mason KT Sladicka SJ 《Aviation, space, and environmental medicine》1999,70(4):316-320
BACKGROUND: The incidence, injury history and aeromedical disposition of anterior cruciate ligament (ACL) reconstruction among Army aviators is unknown. METHODS: The U.S. Army Aviation Epidemiology Data Register was queried for the study period of calendar years 1988-95. Factors considered included age, gender, type and mechanism of injury, prior history of ACL reconstruction, and final aeromedical disposition. The population was divided into two groups: Group I aviators had no history of ACL injury before entering aviation service, while Group II aviators had ACL reconstructions prior to entering aviation service. The data set was analyzed to determine the incidence of ACL reconstruction, to characterize the type and mechanism of injury and to determine the risk of aeromedical termination from service. RESULTS: The ACL reconstruction rate (ACL reconstructions/1000 aviators per year) was 0.52 overall, 0.50 for males and 1.39 for females. Sports accounted for 76% of the injuries requiring ACL reconstruction. The ACL reconstruction rate in Group I was 0.050%, while that of Group II was 63.3%. Among Group I aviators requiring ACL reconstruction, 94.3% returned to aviation service, 2.3% were aeromedically terminated and 3.4% were lost to follow-up. Among Group II aviators requiring revision ACL reconstruction, 60% returned to aviation service and 40% were aeromedically terminated. CONCLUSION: Female aviators and Group II aviators had the greatest risk of requiring ACL surgery. Group II aviators had a greater likelihood of undergoing a revision ACL reconstruction and subsequent aeromedical termination compared with an initial ACL reconstruction for Group I aviators. 相似文献
180.
In England, recent health care reforms emphasise the role of clinical guidelines in promoting effective and efficient health care. Introducing economic data into guidelines raises some methodological issues: specifically, the provision of valid and generalisable cost estimates, the weight placed upon cost 'evidence', and the presentation of cost-effectiveness information in a manner accessible to clinicians. A series of primary care guidelines, explicitly including consideration of health economic information, have recently been published, intended to help clinicians to aggregate the attributes of treatment choices to derive treatment recommendations consistent with both the clinical decision-making process and social objectives. Clinicians involved in developing guidelines responded well to the process and consistently managed to agree treatment recommendations, often after considerable debate about the evidence for treatment. In none of the guideline areas, all of which addressed common diseases, was there adequate information to estimate a cost per quality-adjusted-life-year, and it is unclear how helpful this approach would have been had it been possible. The implications of this method are discussed, guidance offered for economists new to guideline development and future areas of work identified. 相似文献