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991.
Xu WH Dai Q Xiang YB Zhao GM Zheng W Gao YT Ruan ZX Cheng JR Shu XO 《British journal of cancer》2006,95(11):1586-1592
We evaluated animal food intake and cooking methods in relation to endometrial cancer risk in a population-based case-control study in Shanghai, China. A validated food frequency questionnaire was used to collect the usual dietary habits of 1204 cases and 1212 controls aged 30-69 years between 1997 and 2003. Statistical analyses were based on an unconditional logistic regression model adjusting for potential confounders. High intake of meat and fish was associated with an increased risk of endometrial cancer, with adjusted odds ratios for the highest vs the lowest quartile groups being 1.7 (95% confidence interval: 1.3-2.2) and 2.4 (1.8-3.1), respectively. The elevated risk was observed for all types of meat and fish intake. Intake of eggs and milk was not related to risk. Cooking methods and doneness levels for meat and fish were not associated with risk, nor did they modify the association with meat and fish consumption. Our study suggests that animal food consumption may play an important role in the aetiology of endometrial cancer, but cooking methods have minimal influence on risk among Chinese women. 相似文献
992.
This paper reviews the literature of Takayasu's arteritis (T.A.). The concept of this disease has evolved considerably over the past decades. T.A. was first described by Mikito Takayasu in 1908, and was thought to be restricted to south-east Asia. But due to the increasing reports from all over the world, it is well established that T.A. has world-wide distribution. Clinical presentation varies according to the location of the arterial lesions. In Europe brachiocephalic trunk lesions prevail and are best managed by an arterial reconstruction. Historical background, epidemiology, etiology, pathology, clinical findings, diagnosis, classification, treatment and long-term prognosis are discussed. 相似文献
993.
994.
Spatiotemporal dynamics of the BOLD fMRI signals: toward mapping submillimeter cortical columns using the early negative response. 总被引:2,自引:0,他引:2
The existence of the early-negative blood-oxygenation-level-dependent (BOLD) response is controversial and its practical utility for mapping brain functions with columnar spatial specificity remains questionable. To address these issues, gradient-echo BOLD fMRI studies were performed at 4.7 T and 9.4 T using the well-established orientation column model in the cat visual cortex. A robust transient early-negative BOLD response was consistently observed in anesthetized cat (-0.35 +/- 0.09%, mean +/- SD, n = 8 at 2.9 +/- 0.5 sec poststimulus onset for 4.7 T, TE = 31 ms; -0.29 +/- 0.10%, n = 4 at 3.0 +/- 0.8 sec poststimulus onset for 9.4 T, TE = 12 ms). In addition to its temporal evolution, the BOLD response also evolved dynamically in the spatial domain. The initially spatially localized early-negative signal appeared to dynamically drain from the active sites toward large vessels, followed by a wave of the delayed positive signal, which exhibited similar spatiotemporal dynamics. Only the early-negative BOLD response within 2 sec of the stimulus onset (not the entire dip) yielded columnar layouts without differential subtraction. The functional maps of two orthogonal orientations using the first 2-sec dip were indeed complementary. On the other hand, the delayed positive BOLD response appeared diffused and extended beyond the active sites. It was thus less suitable to resolve columnar layouts. These results have implications for the design and interpretation of the BOLD fMRI at columnar resolution. Magn Reson Med 44:231-242, 2000. 相似文献
995.
Yu YQ Giocanti N Averbeck D Megnin-Chanet F Favaudon V 《International journal of radiation biology》2000,76(7):901-912
PURPOSE: To determine how radiation-induced arrest in G2 affects the response of mammalian cells to a challenging dose of radiation or to antitumour drugs producing DNA double-strand breaks. MATERIALS AND METHODS: V79 fibroblast survival to 5 Gy gamma-rays followed at intervals by 3 Gy irradiation or by contact with an equitoxic dose of neocarzinostatin or etoposide, was measured by clonogenic assays. The pattern of radiation-induced DNA double-strand breaks was determined by filter elution and CFGE (continuous field gel electrophoresis) or PFGE (pulsed-field gel electrophoresis) in G2-arrested cells as well as in nonpre-irradiated asynchronous or synchronized cells. The cell-cycle phase specificity of drug susceptibility was determined in synchronized HeLa cells. RESULTS: Cell kill by radiation-drug combined treatment varied markedly with the time elapsed after priming irradiation. Pre-irradiated, G2-arrested V79 fibroblasts demonstrated excess double-stranded DNA cleavage upon re-irradiation and hypersensitivity to drugs and radiation, although maximum resistance to both neocarzinostatin and etoposide in synchronized HeLa cells was in G2. This effect occurred in the megabase range only, with a peak around 4 Mbp; no change in the electrophoretic migration profile of DNA was observed below 1 Mbp. Moreover, the DNA migration profile and the yield of DNA cleavage in G2-arrested cells were close to those expected from S-phase cells. CONCLUSION: The available data suggest that mechanisms operating within the radiation-induced G2 block promote susceptibility to DNA double-strand break inducers at this stage. It is also proposed that the conformation of DNA in cells accumulated in G2 following irradiation bears resemblance to that for cells in S phase, due either to active repair mechanisms or to inhibition of chromosome disentanglement at the S-G2 transition. 相似文献
996.
Hollingworth W Todd CJ Bell MI Arafat Q Girling S Karia KR Dixon AK 《Clinical radiology》2000,55(11):825-831
AIM: To provide information about the diagnostic and therapeutic impact of magnetic resonance imaging (MRI) and to compare the findings across diagnostic groups. MATERIALS AND METHODS: A prospective, observational study of 2017 consecutive referrals for MRI of the head, spine or knee at four imaging centres. Clinicians completed questionnaires before MRI stating initial diagnoses, diagnostic confidence and treatment plans. After imaging, a second questionnaire evaluated clinicians' revised diagnosis and treatment plans in the light of imaging findings. Patients were grouped into nine diagnostic categories for analysis. Comparison between pre- and post-imaging was used to assess the diagnostic and therapeutic impact of MRI. RESULTS: In seven of nine diagnostic groups MRI findings were associated with a diagnostic impact. Diagnoses were revised or discarded following normal MR findings and diagnostic confidence was increased by confirmative MR findings. There was no statistically significant diagnostic impact for suspected pituitary or cerebello-pontine angle lesions. In five of nine diagnostic groups (knee meniscus, knee ligament, multiple sclerosis, lumbar and cervical spine) MRI findings had a clear impact on treatment plans. CONCLUSION: This study demonstrates that in most diagnostic categories, MRI influences diagnosis and treatment. However, experimental studies are needed to prove that these diagnostic and therapeutic impacts lead to improved health.Hollingworth (2000). Clinical Radiology55, 825-831. 相似文献
997.
PURPOSE: To determine if multiphasic injection provides uniform, prolonged vascular contrast medium enhancement at computed tomographic (CT) angiography. MATERIALS AND METHODS: With a computer-based, compartmental model of the cardiovascular system, theoretic analysis was performed to estimate an injection algorithm for uniform, prolonged vascular enhancement. For algorithm validation, four pigs were scanned after intravenous injection of 50 or 70 mL of contrast medium (282 mg of iodine per milliliter). Uni-, bi-, and multiphasic injection schemes were tested. In most cases, the initial injection rate was 2 mL/sec. In each CT study, 27 dynamic images were acquired every 2 seconds at a fixed mid-abdominal aortic level. Time-enhancement curves were calculated. Injection duration, peak aortic enhancement, and enhancement uniformity (duration of enhancement achieved within 90% of the peak [90% DCE]) were evaluated. RESULTS: Theoretic and experimental results agreed well. Compared with uniphasic injection, biphasic injection resulted in more prolonged enhancement but generated two enhancement peaks with a valley between, and multiphasic injection yielded more uniform and prolonged enhancement. With 50- and 70-mL multiphasic injections, respectively, injection duration increased by 32% and 51%, peak enhancement decreased by 19% and 18%, and 90% DCE increased by 81% and 94%. CONCLUSION: Uniform, prolonged vascular enhancement, which is desirable for CT angiography and essential for steady-state quantification of blood volume in organs, can be achieved with multiphasic injection. 相似文献
998.
Survival following emergency surgery for ruptured abdominal aortic aneurysm remains poor and is in stark contrast to that for elective repair. We have carried out a 5-year retrospective observational study to determine the long-term (5-year) survival of patients following emergency surgery for ruptured abdominal aortic aneurysm at a district general hospital in East Anglia. A total of 99 patients presented to the operating theatre for emergency repair of ruptured abdominal aortic aneurysm in this 5-year study period. In-hospital mortality was 70% and was unchanged over the 5 years. Overall long-term survival in those patients discharged from hospital was good. The ICU cost per long-term survivor was calculated to be pound sterling 36750. 相似文献
999.
OBJECTIVE: To study alterations of serum levels of the pancreatic reg family of proteins in two models of acute pancreatitis. SUMMARY BACKGROUND DATA: The pancreatic reg family of proteins is expressed in the acinar pancreas. Reg I (pancreatic stone protein, PSP) and reg III (pancreatitis-associated protein, PAP) are induced after the onset of acute pancreatitis, and both have been proposed as potential markers of pancreatitis. METHODS: Pancreatitis was induced in rats by either retrograde infusion of sodium taurocholate or by direct trauma. Serum samples were obtained daily for 4 days after the procedure, and the animals were then killed. Twelve animals underwent sham procedure and six underwent daily analysis without surgery. Levels of reg I/PSP and reg III/PAP were estimated by enzyme-linked immunosorbent assay. RESULTS: Reg III/PAP levels increased significantly the first day after induction of both types of pancreatitis and rapidly returned to baseline in all survivors. Even animals who received retrograde infusion of saline showed a mild increase in reg III/PAP on the first day, whereas control animals that did not undergo surgery showed no variations. Reg I/PSP serum levels remained unchanged throughout all experimental periods. Postinjury reg III/PAP levels significantly correlated with severity of the pancreatic injury and animal survival; reg I/PSP levels did not. CONCLUSION: After induction of pancreatitis, serum levels of reg I and III protein differ significantly. Reg III/PAP levels are a sensitive marker of pancreatic injury and early in the disease may be a useful prognostic indicator for disease severity. 相似文献
1000.
Zhao ZQ Nakamura M Wang NP Velez DA Hewan-Lowe KO Guyton RA Vinten-Johansen J 《The Journal of surgical research》2000,94(2):133-144
BACKGROUND: Myocardial injury during early reperfusion (R) has been well documented. However, the extent and time course of myocardial injury during late R are still unclear. The purpose of this study was to determine the extent of regional contractile and endothelial dysfunction and myocardial blood flow (MBF) defect as well as extension of infarction in association with neutrophil (PMN) actions during R. MATERIALS AND METHODS: A total of 29 dogs underwent a protocol of 1 h LAD ischemia followed by 6, 24, 48, and 72 h of R, respectively. Regional contractile function (sonomicrometry), MBF (colored microspheres), infarct size (triphenyltetrazolium chloride staining), and PMN localization (immunohistochemistry) were determined. RESULTS: Percentage segmental shortening at 6, 24, 48, and 72 h of R was significantly blunted (-1.8 +/- 1.2,* - 0.37 +/- 0. 6,* 0.04 +/- 0.2,* and 5.9 +/- 1.2* vs baseline 17.7 +/- 0.8). MBF (ml/min/g) was attenuated at 24 (0.27 +/- 0.03*), 48 (0.46 +/- 0. 07*), and 72 h of R (0.48 +/- 0.06*) vs 6 h of R (0.65 +/- 0.06). Infarct size increased from 6 (27 +/- 2%) to 24 h of R (41 +/- 2%*) with no further increase at 48 and 72 h of R, consistent with a peak of creatine kinase activity. PMN adherence (mm(2) endothelium) to left anterior descending coronary artery (LAD) segments was increased after 6 h of R (63 +/- 3*) vs nonischemic left circumflex coronary artery (LCX) segments (42 +/- 2) with a peak at 48 h of R (111 +/- 5*). Endothelium-dependent vascular relaxation in the LAD was also blunted at 6, 24, and 48 h of R. Immunostaining revealed CD18-positive PMNs were mainly accumulated in intravascular space during 6 h of R with an increase in migration of PMNs seen at 24 h of R, consistent with a peak of myeloperoxidase release. Myeloperoxidase activity in a given area at risk sample was significantly correlated with infarct extension during the first 24 h of R. CONCLUSIONS: These results provide pathologic evidence for myocardial injury during the extended R and a basis for exploration of interventions designed to limit myocardial injury after ischemia. (*P < 0.05 vs Baseline, 6 h of R and LCX segments.) Copyright 2000 Academic Press. 相似文献