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341.
The significance of neoangiogenesis in the metastasis of nasopharyngeal carcinoma (NPC) was investigated to clarify the role neovascularity in the prognosis of NPC and the probability of antiangiogenesis preventing NPC from distant metastasis. A group of 52 patients presenting with metastatic NPC were selected and strictly paired one-to-one, in sex, age, T stage, and N stage, with another 52 patients with non-metastatic NPC, who had survived for a long time after therapy. The tumor tissues of all 104 patients were retrieved for computer-assisted, immunohistochemical analysis of tumor vasculature. Counts of the microvessels and the relative area of all microvessels per image were significantly higher in metastatic NPC than they were in curable, non-metastatic NPC, while the average area of the microvessels and their average perimeter of in metastatic NPC were smaller than in non-metastatic disease. No significant difference in any microvessel parameter was found among the various types of metastasis. The alterations of microvessel parameters were significantly linked to the metastasis of NPC. Evaluation of neovascularity by computer image analysis may be helpful in estimating the prognosis of NPC and in determining the indicators for aggressive multimodal treatments. 相似文献
342.
E Christiansen M R?der A Tibell CN Hales S Madsbad 《Canadian Metallurgical Quarterly》1998,15(9):739-746
A few small studies of white persons have found a positive association between serum albumin and blood pressure. However, this association might be due to ionized calcium. No data on albumin or ionized calcium have appeared for African Americans or Hispanics, and few for women. To explore the association of serum albumin (g/L) and ionized calcium (mmol/L) with both systolic and diastolic blood pressure, data from the Third National Health and Nutrition Examination Survey, 1988-94, were analyzed. Results from multiple regressions, controlling for age, overweight, alcohol intake, hematocrit, pulse, antihypertensive medication, and smoking indicate that serum albumin is positively correlated (P < 0.01) to systolic and diastolic blood pressure among non-Hispanic white men 25-59 and 60-89 years old. Ionized calcium was associated negatively with diastolic blood pressure among younger Mexican-American men. In this national sample, serum albumin was consistently associated with systolic and diastolic blood pressure only among non-Hispanic white men. 相似文献
343.
344.
H Glatt I Bartsch S Christoph MW Coughtrie CN Falany M Hagen R Landsiedel U Pabel DH Phillips A Seidel Y Yamazoe 《Canadian Metallurgical Quarterly》1998,109(1-3):195-219
Sulfation is a common final step in the biotransformation of xenobiotics and is traditionally associated with inactivation. However, the sulfate group is electron-withdrawing and may be cleaved off heterolytically in some molecules leading to electrophilic cations which may form adducts with DNA and other important cellular structures. Since endogenous sulfotransferases do not appear to be expressed in indicator cells of standard mutagenicity tests, rat and human sulfotransferases have been stably expressed in his- Salmonella typhimurium strain TA1538 and Chinese hamster V79 cells. Using these recombinant indicator cells, sulfotransferase-dependent genotoxic activities were detected with N-hydroxy-2-acetylaminofluorene, 2-acetylaminofluorene (in the presence of co-expressed rat cytochrome P450 1A2), hycanthone, 1'-hydroxysafrole, alpha-hydroxytamoxifen and various benzylic alcohols derived from polycyclic aromatic hydrocarbons. In several cases, it was critical that the reactive sulfuric acid conjugates were formed directly within the indicator cells, owing to the inefficient penetration of cell membranes. In other cases, spontaneous benzylic substitution reactions with medium components, such as halogenide ions or amino acids, led to secondary, membrane-penetrating reactive species. Different sulfotransferases, including related forms from rat and human, substantially differed in their substrate specificity towards the investigated promutagens. It is known that some sulfotransferases are expressed with high tissue and cell type specificities. This site-dependent expression together with the limitations in the distribution of reactive sulfuric acid conjugates may explain organotropic effects of compounds activated by this metabolic pathway. 相似文献
345.
PURPOSE: The purpose of this study was to assess the outcome after the shortening and reimplantation of tortuous internal carotid arteries to prevent kinking after endarterectomy. METHODS: Through a review of prospective records, we studied patients who underwent carotid endarterectomy (CEA) (n = 233) between 1993 and 1996 who had symptomatic stenosis of the internal carotid artery (ICA) of more than 70%. An elongated proximal ICA was excised, and the ICA was reimplanted into the bifurcation in 30 (13%) patients, with additional patch angioplasty in 5 patients. Of the remaining 203 patients, 50 (21%) had Dacron patch angioplasty, and the rest had conventional CEA with simple closure. RESULTS: In the reimplanted group, one patient had a minor stroke with complete recovery on discharge. Three patients (10%) had neck hematomas requiring reexploration, but in none of these was the bleeding from the artery. At mean follow-up of 15 months, 93% of the arteries were widely patent. Significant stenosis secondary to neointimal hyperplasia was detected in only two patients, for a restenosis rate of 6.7%, which is in line with other published reports. In the control group, 8 (3.9%) patients had perioperative transient ischemic attacks, 5 (2.5%) had strokes, and 13 (6.4%) had hematomas requiring evacuation. At follow-up, 14 (6.9%) of the arteries had restenosed. CONCLUSION: In carotid surgery, reconstructive techniques must be tailored to operative findings. Excision of a tortuous elongated proximal ICA with reimplantation is not associated with additional mortality or morbidity rates over those of conventional CEA alone and has the advantage of removing disease at the bifurcation. This procedure was carried out in 13% of our patients and should be a procedure with which the vascular surgeon is familiar. 相似文献
346.
L Hinton CN Jenkins S McPhee C Wong KQ Lai A Le N Du D Fordham 《Canadian Metallurgical Quarterly》1998,186(11):677-683
Adolescent health problems are often undetected in physicians' offices. The Dartmouth Primary Care Cooperative Information Project has developed a validated and reliable approach to identify adolescent health problems and initiate education in a school setting. A self-administered, anonymous, 26-item questionnaire was given to 204 students in a rural high school. Responses were scanned into PC-based software. Within one working day students were given individualized letters identifying their problem health issues as detected by the questionnaire and recommendations for education. Ninety-nine percent of students participated. Six weeks later 49% of a sample of 41 students reported reading the information and 50% planned to change behavior. This standardized, validated strategy of adolescent health assessment, feedback, and education was feasible for use in schools. The school responded to the data by employing a psychologist to address mental health needs. 相似文献
347.
CN Sternberg 《Canadian Metallurgical Quarterly》1998,25(3):435-449
For clinical stage I seminoma, conventional management consists of adjuvant RT after orchiectomy. Only 5% of patients relapse. The majority can be salvaged by chemotherapy. The overall survival of 98% is excellent. Seminoma is radiosensitive. A lower dose of RT is required than for NSGCT. Standard therapy presently is 30 Gy in 3 weeks, as suggested by the MRC study. RT is generally well tolerated. There have been recent concerns about second malignancies after 10 to 15 years. Surveillance studies have shown that 18% of patients relapse, the majority in para-aortic lymph nodes. About 15% require salvage RT and 5% salvage chemotherapy. Second relapses are seen in patients treated with RT at first relapse, and occur outside of the radiation field. The main advantage of surveillance is that 80% of patients can be spared slightly toxic overtreatment. The main disadvantage is the need for long-term follow-up, which is expensive and stressful to the patient. Good patient compliance, mandatory to an observation policy, is often difficult on a long-term basis. Seminoma is clearly responsive to chemotherapy. Adjuvant carboplatin in clinical stage I has only been evaluated in two studies. Because reliable prognostic factors have not been established, a high-risk group cannot be identified, and chemotherapy must be given to all patients. Whether or not one cycle of chemotherapy is sufficient requires further confirmation, particularly in view of the results with carboplatin as compared with cisplatin in patients with advanced NSGCT. Results of the randomized MRC trial comparing RT with carboplatin are of interest. 相似文献
348.
SP Howard SJ Park L Hughes-Davies CN Coleman BD Price 《Canadian Metallurgical Quarterly》1996,2(2):269-276
Dental somatosensory evoked potentials (SEPs) corresponding to the stimulus intensity levels were recorded at 6 different levels of intensity presented in a randomized order. The relationships between the amplitude of the late SEP component with latency between 150 and 300 msec and each stimulus intensity level were also compared in conditions of randomized intensity and constant intensity. The amplitude of the late component increased significantly with the increased stimulus intensity both in the randomized and constant intensity stimulation. The amplitude of the late component in the randomized stimulation with a 1-sec interstimulus interval (ISI) increased in the same manner as that in the constant intensity condition with a 1-sec ISI. The randomized stimulation with the prolonged ISI increased the amplitude of the late component. The latency of the late positive component significantly increased with the randomized stimulation with a 3-sec ISI. This phenomenon might be attributable to the psychological contamination. SEP recording in the randomized dental stimulation with a 1-sec ISI may have applications in neuropharmacological research or physiological research on pain and evaluation of the effects of analgesics, anesthetics, acupuncture and transcutaneous electrical nerve stimulation (TENS). 相似文献
349.
SM Haffner R D'Agostino L Mykk?nen CN Hales PJ Savage RN Bergman D O'Leary M Rewers J Selby R Tracy MF Saad 《Canadian Metallurgical Quarterly》1998,29(8):1498-1503
BACKGROUND AND PURPOSE: Insulin resistance and hyperinsulinemia have been associated with atherosclerosis. Recent attention has focused on the possible role of proinsulin because most radioimmunoassays for insulin cross-react with proinsulin. Therefore, it is not known which of the two, insulin per se or proinsulin, is more strongly related to atherosclerosis. METHODS: We examined the relation between fasting proinsulin, fasting split proinsulin, fasting and 2-hour insulin (after oral glucose load), and intima-media wall thickness (IMT) in the common carotid artery (CCA) and internal carotid artery (ICA) in 985 nondiabetic subjects from the Insulin Resistance Atherosclerosis Study, a multiethnic study of insulin resistance and atherosclerosis. RESULTS: In the overall population, a weak but significant relation between proinsulin and CCA IMT was observed (r=0.07, P=0.029). However, the relation between proinsulin and IMT was stronger in Hispanics and non-Hispanic whites than in African Americans. In non-Hispanic whites and Hispanics, significant correlations between CCA and proinsulin (r=0.087) and between ICA and proinsulin (r=0.101), split proinsulin (r = 0.092), and fasting insulin (r = 0.087) were observed. The significant correlations became more attenuated (and nonsignificant) after adjustment for cardiovascular risk factors, especially plasminogen activator inhibitor-1 (PAI-1). CONCLUSIONS: The association between proinsulin and IMT, while weak, appears to be stronger than the association between insulin and IMT. Adjustment for PAI-1 markedly attenuated the association between proinsulin and IMT, suggesting a possible mediating role for PAI-1 in this association. It is possible that proinsulin may represent a marker of atherosclerosis rather than a causal factor for atherosclerosis. Studies of the insulin resistance syndrome and atherosclerosis that use insulin as a surrogate for insulin resistance should consider the use of specific insulin assays as well as determination of proinsulin concentrations. 相似文献
350.
CA Marco CN Schoenfeld PM Keyl ED Menkes MC Doehring 《Canadian Metallurgical Quarterly》1998,5(12):1163-1168
OBJECTIVE: To determine the diagnoses and outcomes of geriatric patients with abdominal pain, and to identify variables associated with adverse outcomes. METHODS: Geriatric emergency patients (aged 65 years and older) with a complaint of abdominal pain were participants in this longitudinal case series. Eligible patients were followed by telephone contact and chart review, to determine outcomes and final diagnoses. RESULTS: Of 380 eligible patients, follow-up information was available for 375 (97%), for the two months following the ED visit. Final diagnoses included infection (19.2%), mechanical-obstructive disorders (15.7%), ulcers/hypersecretory states (7.7%), urinary tract disease (7.7%), malignancy (7.2%), and others. Although 5.3% of the patients died (related to presenting condition), most (61.3%) patients ultimately recovered. Surgical intervention was required for 22.1% of the patients. Variables associated with adverse outcomes (death, and need for surgical intervention) included hypotension, abnormalities on abdominal radiography, leukocytosis, abnormal bowel sounds, and advanced age. Most physical examination findings were not helpful in identifying patients with adverse outcomes. This study demonstrated a higher incidence of malignancy (7.2%) and a lower incidence of disease necessitating surgical intervention (22.1%) than previously reported. CONCLUSIONS: The majority of geriatric emergency patients with abdominal pain have significant disease necessitating hospital admission. Morbidity and mortality among these patients are high, and specific variables are strongly associated with death and the need for surgical intervention. Absence of these variables does not preclude significant disease. Physical examination findings cannot reliably predict or exclude significant disease. These patients should be strongly considered for hospital admission, particularly when fever, hypotension, leukocytosis, or abnormal bowel sounds are present. 相似文献