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51.
Bourdillon MC Poston RN Covacho C Chignier E Bricca G McGregor JL 《Arteriosclerosis, thrombosis, and vascular biology》2000,20(12):2630-2635
Intercellular adhesion molecule (ICAM)-1, a major adhesion molecule, plays a critical role in the homing of leukocytes to sites of atherosclerotic lesions. However, very little is known on the role of ICAM-1 in initiating and perpetuating vascular lesions in ApoE(-/-) mice fed a chow or a fat diet. This study has investigated the mean aortic lesions in mice (C57BL6 background) with a single-knockout (ApoE(-/-)) or double-knockout (DKO; ApoE(-/-), ICAM-1(-/-)) fed a chow or a fat diet over a period of 3, 6, 15, and 20 weeks. A 3-fold reduction in lesion size was observed at all time points in DKO mice fed a chow diet. However, in DKO mice fed a fat diet, a marked reduction in the aortic lesion was observed at 3 and 15 weeks, which did not reach a significant level at 6 and 20 weeks. This study shows in essence that DKO mice are protected from developing significant lesions for up to 6 weeks when fed a chow diet and from 3 to 6 weeks when fed a fat diet. After 6 weeks, the lesion size of the DKO mice follows that of the single-knockout mice when fed a chow diet and gets to the same level in mice fed a fat diet. Plasma cholesterol levels were not altered as a result of ICAM-1 deficiency. These studies show that ICAM-1 is implicated in the formation and progression of atherosclerotic lesions. 相似文献
52.
G J Poston R Saydjari J Lawrence R W Alexander C M Townsend J C Thompson 《Journal of gerontology》1990,45(6):B220-B225
We examined the effect of age on the adaptive capacity of small bowel mucosa following 60% enterectomy. Two groups of male Fischer 344 rats (3 mo old and 26 mo) underwent either a mid-small bowel transection and reanastomosis (control) or 60% proximal enterectomy beginning at the duodenojejunal junction. Rats were sacrificed at 5, 14, and 21 days after operation, and the mucosa was weighed and assayed for DNA, RNA, protein, and polyamine concentration and content. Ornithine decarboxylase activity was also measured in ileal mucosa at 5 days after surgery. Young rats had completed the adaptive hyperplastic response within 2 weeks after operation by all biochemical measurements; similar adaptation was not seen until 3 weeks after operation in the old rats. We conclude that although the capacity to achieve intestinal adaptation after enterectomy is preserved into old age in rats, this compensatory response is delayed. 相似文献
53.
54.
Measurement of the effects of an integrated, point-of-care computer system on quality of nursing documentation and patient satisfaction 总被引:1,自引:0,他引:1
This quasi-experimental, modified time series study measured the effects of the nursing module of a point of care clinical information system on nursing documentation and patient satisfaction. Measurements were taken before implementation of the module and at 6-, 12-, and 18-month intervals postimplementation. Quality of nursing documentation was measured by compliance to items applicable to nursing documentation selected from the Joint Commission on Accreditation of Healthcare Organizations (JCAHO) Closed Medical Review Tool. Patient satisfaction was measured by using the Risser Patient Satisfaction Scale. The study data showed a statistically significant increase in the quality of nursing documentation after implementation of the computerized nursing documentation system, as well as a decrease in variability in charting, as evidenced by a decrease in standard deviations. A significant increase in charting compliance was still occurring between the 12- and the 18-month time points after initiation of automated documentation. The point of care computer system did not seem to affect patient satisfaction with the nurse-patient relationship. 相似文献
55.
Nitric oxide synthase activities in placental tissue from normotensive, pre-eclamptic and growth retarded pregnancies 总被引:6,自引:0,他引:6
Nicholas H. Mmorris WellBeing Training Fellow Suren R. Sooranna Senior Biochemist Jonathan G. Learmont Research Registrar Lucilla Poston Professor Bruce Ramsey Registrar/Lecturer JeremyD. Pearson Professor Philip J. Steer Professor 《BJOG : an international journal of obstetrics and gynaecology》1995,102(9):711-714
56.
M C Stripling D C Martin D L Chatman R V Zwaag W M Poston 《Fertility and sterility》1988,49(3):427-431
This retrospective study demonstrates an increased documentation of subtle appearances of endometriosis. This documentation was associated with an increased emphasis on excising these lesions for histologic examination. Endometriosis was documented in pink, clear, red, white, and puckered black lesions in 106 (97%) of 109 patients. This included 22 (100%) of 22 patients undergoing laparotomy and 84 (97%) of 87 patients undergoing laparoscopy. Subtle lesions were documented at laparoscopy in 32% of patients in the first 5 months and in 72% of patients in the last 5 months of the study. The increased documentation of these subtle lesions appeared to be related to an increased awareness and anticipation of subtle lesions. The ability to detect such lesions increased with experience and was reinforced by histologic confirmation. 相似文献
57.
Depression is a well-established risk factor for cardiovascular disease-related morbidity and mortality. It is common to screen for depression in patients undergoing coronary revascularization prior to revascularization; however, the validity of this assessment is unclear as some patients may experience transient, reactive depression rather than persistent depression. The authors evaluated whether an initial or 1-month postprocedure screen was optimal for identifying consistently depressed patients. Depression at 1-month postprocedure was a stronger predictor of depression at months 2 to 6 than baseline depression. After adjusting potential confounding variables, there was a much stronger relationship between 1-month and 6-month depression status (OR = 28.7 if depressed at 1 month, p < .001) than between baseline and 6-month depression status (OR = 6.5 if depressed at baseline, p < .001). Screening for depression at the time of revascularization is not as predictive of depression at 6 months as it is 1 month postprocedure. 相似文献
58.
Cryotherapeutic ablation of liver tumours 总被引:10,自引:0,他引:10
BACKGROUND: This paper reports a 7-year experience of cryoablation for colorectal and non-colorectal liver metastases. METHODS: A retrospective review was undertaken of patients treated in two adjacent UK centres in the north-west of England. RESULTS: Over a 7-year period (1993-2000), 57 patients underwent cryotherapy for malignant hepatic tumours (41 colorectal, 16 non-colorectal). In the patients with colorectal metastases, preoperative carcinoembryonic antigen (CEA) levels fell significantly, from a mean of 444.1 to 6.22 micro g/l (P = 0.002). One patient died, two developed cryoshock and six had cardiorespiratory complications. All patients with colorectal metastases subsequently received 5-fluorouracil-based chemotherapy. The remaining 16 patients with non-colorectal tumours (seven neuroendocrine metastases, five hepatocellular carcinomas, three sarcomas, one cholangiocarcinoma) all received cryotherapy alone, with no major complications. The median survival for patients with non-colorectal metastases was 37 months, compared with 22 months for those with colorectal metastases (P = 0.005). CONCLUSION: Hepatic cryotherapy is effective and safe, as demonstrated by the significant reduction in postoperative CEA concentration and the low risk of complications. However, this initial short-term success was not reflected in 5-year survival rates. Cryotherapy for non-colorectal metastases had a greater long-term survival benefit and is a useful means of controlling symptoms. 相似文献
59.
G Low GJ Irwin G Haddock SV Maroo 《Journal of Medical Imaging and Radiation Oncology》2006,50(3):249-251
The Currarino triad is a complex anomaly consisting of an anorectal malformation, a sacral bone defect and a presacral mass. It was first described in 1981 and since then, approximately 250 cases have been reported. Radiology has an important part to play in the diagnosis of this entity, as the imaging features are characteristic. We report a case of Currarino triad in an infant who presented with intractable constipation and discuss relevant MRI and plain radiography findings. 相似文献
60.
Loss of tumor-promoting activity of unleaded gasoline in N- nitrosodiethylamine-initiated ovariectomized B6C3F1 mouse liver 总被引:1,自引:0,他引:1
Unleaded gasoline (UG) vapor (2056 ppm) increased the incidence of liver
tumors in a chronic bioassay and exhibited tumor-promoting activity in
N-nitrosodiethylamine (DEN)-initiated female mouse liver. Estrogen
inhibited mouse liver tumor development and the hepatocarcinogenic and
tumor-promoting dose of UG produced uterine changes suggestive of estrogen
antagonism. To directly test the hypothesis that UG-induced tumor-promoting
ability is secondary to its interaction with the mouse liver tumor
inhibitor, estrogen, we compared the tumor-promoting ability of UG in
ovariectomized (Ovex) mice with the hepatic tumor-promoting ability of UG
in intact mice. Ovaries were surgically removed at 4 weeks of age. Exposure
to wholly vaporized UG (2018 ppm) under bioassay and tumor-promoting
conditions began at 8 weeks of age. After 4 months of exposure, UG
increased relative liver weight and hepatic microsomal cytochrome P450
pentoxyresourfin-O- dealkylase and ethoxyresorufin-O-deethylase activity to
a similar extent in intact and Ovex mice. Non-focal hepatocyte
proliferation, as measured by the incorporation of bromo-deoxyuridine, was
not changed by UG exposure and was similar in all treatment groups. After 4
months of exposure to DEN-initiated mice, UG significantly increased the
volume fraction of liver occupied by foci (three-fold) as compared to
control intact mice. As expected, volume of foci was elevated in
DEN/Ovex/control mice as compared to DEN/intact/control mice. In DEN/Ovex
mice UG did not significantly increase the focal volume fraction. Thus, the
tumor promoting activity of UG, as demonstrated by increased volume
fraction of liver occupied by hepatic foci in intact mice, is greatly
attenuated in Ovex mice. The volume fraction data in Ovex mice support the
hypothesis that the tumor promoting activity of UG is dependent upon the
interaction of UG with ovarian hormones. These data also indicate that
hepatic microsomal cytochrome P450 PROD and EROD induction, hepatomegaly
and non-focal hepatic LI are not specific markers of hepatic tumor
promoting activity of UG.
相似文献