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991.
Nitric oxide synthase as a marker in colorectal carcinoma.   总被引:7,自引:0,他引:7  
Elevated inducible nitric oxide synthase (iNOS) activity has been found in 60 per cent of colon adenomas and 20 to 50 per cent of adenocarcinomas. We postulated that high levels of iNOS may increase the invasive and metastatic potential of colon carcinoma and could be indicative of survival potential. Data were reviewed for 52 patients with colorectal carcinoma diagnosed in 1991 and 1992. Specimens were stained for iNOS and catalogued as low-activity staining (LAS) or high-activity staining (HAS) on the basis of visual evaluation by three pathologists. Thirty patients were LAS and 22 HAS. Age, sex, preoperative carcinoembryonic antigen, tumor and nodal status, and American Joint Committee on Cancer staging were not different between groups. Forty-six per cent of the HAS group remained alive after 5 years versus 71 per cent in the LAS group. Survival was significantly lower and metastatic status significantly higher in the HAS group. Results indicated that iNOS activity may be a prognostic indicator of long-term survival potential after treatment for colon cancer. In addition results suggested that metastasis was greater in colon carcinoma specimens that maintain an activated iNOS and that these cells clinically react more aggressively. Conclusions are tempered by the fact that results were based on a limited sample size.  相似文献   
992.
The Na+/H+ exchanger (NHE) is activated during ischemia–reperfusion in an effort to restore intracellular pH to normal levels. Inhibition of NHE with non-selective amiloride derivatives has been shown to be neuroprotective and to attenuate free fatty acid efflux during ischemia–reperfusion. We evaluated the effects of SM-20220 (20 μM), a highly selective and specific NHE inhibitor, applied topically onto rat cerebral cortex prior to and during a 20-min period of ischemia. SM-20220 application significantly reduced the ischemia-evoked efflux of myristic, palmitic, and arachidonic acids during both ischemia and reperfusion with significant decreases in linoleic and docosahexaenoic levels during reperfusion. This study confirms the importance of NHEs in eliciting free fatty acid efflux, inhibition of which may be an essential component of the neuroprotective benefits of NHE inhibitors in ischemia–reperfusion injury.  相似文献   
993.
Ocular dominance diagnosis and its influence in monovision   总被引:1,自引:0,他引:1  
PURPOSE: To analyze the response of normal emmetropic subjects to different ocular dominance tests and to analyze the influence of this response in surgically induced monovision. DESIGN: A prospective study of diagnostic accuracy was carried out to analyze the different tests to determine ocular dominance, without a gold standard test. METHODS: Nine different tests were carried out in a group of 51 emmetropic subjects to determine both motor and sensory ocular dominance. For analysis, patients were divided into two groups according to age. Normal ophthalmologic examination results were the inclusion requirement, with normal binocular vision and good stereoacuity. RESULTS: A significant percentage of uncertain or ambiguous results in all tests performed was found, except in the hole-in-card and kaleidoscope tests. When the tests were compared, two by two, the correlation or equivalence found was low and was much lower if tests were compared three by three. CONCLUSIONS: No clear ocular dominance was found in most studied subjects; instead, there must be a constant alternating balance between both eyes in most emmetropic persons, but not in those with pathologic features. This fact would explain the great variability both between and within different kinds of tests. Also, it would establish that the monovision technique is well tolerated in most patients, with unsuccessful results only in those patients with strong or clear dominance. Consequently, it seems appropriate to evaluate patient's dominance before monovision surgery to exclude those individuals with clear dominance.  相似文献   
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BACKGROUND: Fogo selvagem (FS) has been described in several regions of Brazil, including the Western regions of the state of Parana. In 1990, Empinotti et al. reported case studies of 213 patients with FS that were collected from 1976 to 1988. The same author (J.C.E.) has observed that the frequency of cases in these regions of Parana has decreased. OBJECTIVES: The purpose of this study was to clinically and serologically evaluate a small group of the patients originally reported in 1990 and compare data with a group of control individuals. These patients were treated at the onset of the disease with systemic steroids. PATIENTS AND METHODS: Patients with FS, their unaffected relatives (n = 80) and genetically unrelated controls (n = 15) were identified during a field study from 1 May 2001 to 30 June 2002. Sera from nine patients with FS and six normal controls that were collected in the 1976-1988 evaluation were available for this study. The sera were tested by indirect immunofluorescence, enzyme-linked immunosorbent assay (ELISA) and immunoprecipitation using recombinant human desmoglein 1 (Dsg1). RESULTS: Only 16 of the originally identified 213 patients with FS were found during the field studies. Thirteen of the 16 patients were in clinical and serological remission; 20% of normal controls (19 of 95) were positive in the Dsg1 ELISA. The majority of these subjects (17 of 19) were genetically related to FS patients. Six normal controls that were positive in the Dsg1 ELISA in the original survey were found to be negative or weakly positive in this evaluation. CONCLUSION: The reduced frequency of positive serological markers of disease in patients and normal controls from Western Parana, as well as the absence of recurrent disease in previously identified patients, suggest that environmental antigenic stimulation of the population at risk may have decreased in recent years.  相似文献   
997.
Young patients and their parents often are unsure about what represents normal menstrual patterns, and clinicians also may be unsure about normal ranges for menstrual cycle length and amount and duration of flow through adolescence. It is important to be able to educate young patients and their parents regarding what to expect of a first period and about the range for normal cycle length of subsequent menses. It is equally important for clinicians to have an understanding of bleeding patterns in girls and adolescents, the ability to differentiate between normal and abnormal menstruation, and the skill to know how to evaluate young patients' conditions appropriately. Using the menstrual cycle as an additional vital sign adds a powerful tool to the assessment of normal development and the exclusion of pathological conditions.  相似文献   
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CAN is a common cause of late graft loss. Nephrotoxicity due to CNIs is known to contribute to CAN. We retrospectively evaluated the efficacy and safety of SRL in pediatric renal Tx recipients showing CAN in their allograft biopsy. Twenty-one patients aged 10.4 +/- 4.6 yr at Tx time receiving CNIs as primary immunosuppression were converted to SRL at 58.9 +/- 49.1 months after Tx, due to progressive decline of renal function and biopsy proven CAN. Mean follow-up after switch was 19.7 +/- 9.5 months. All patients received CsA as part of the immunosuppressive regimen, at a mean dose 4.4 +/- 1.2 mg/kg/day. Mean daily dose of SRL three month after conversion was 2.6 +/- 0.8 mg/body surface area/day and the mean through levels where 6.9 +/- 2.5 ng/mL. Graft biopsies showed Grade I CAN in 12 children and Grade II CAN in nine. After SRL introduction, there were neither acute rejection episodes nor graft losses. GFR improved at three months and was sustained thereafter only in children with Grade I CAN. Post-Tx time at conversion was the only significant variable between patients who had Grade I CAN and Grade II CAN (33.6 +/- 33.3 vs. 92.7 +/- 47.5 months, p = 0.003). Nine patients had no AEs, six patients had nine SAE: five diarrhea, one herpes zoster, one pancreatic pseudo cyst, one pneumonia, and one Influenza A infection; 11 patients had 13 AEs: six oral aphthous ulcers, three urinary tract infections, two herpes simplex, one lymphedema, and one nephrotic proteinuria. Significant improvement of GFR occurred in Grade I CAN group at three months from conversion and was sustained during follow-up. Those who had Grade II CAN experienced no change in GFR. The incidence of AEs and SAE is of concern and further studies are necessary to assess their relevance.  相似文献   
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