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排序方式: 共有1309条查询结果,搜索用时 11 毫秒
991.
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BACKGROUND: In the last 15 years, family physicians and general internists have adopted flexible fiberoptic endoscopy as a procedure to screen patients at risk of premature death from colorectal cancer. There has been controversy regarding the ability of non-fellowship-trained primary care physicians to extend this experience to full colonoscopy. METHODS: The results of 1048 consecutive colonoscopy examinations performed by a family physician over a 9-year period were tabulated. Outcomes measured included the reach-the-cecum rate (RCR), use of medication, complication rate, and diagnostic yield. In a convenience sample of 110 cases, the effectiveness of the non-narcotic analgesic ketorolac was assessed by the RCR. Outcomes of cases in which ketorolac was used were compared with cases in which traditional sedation and analgesia were used. RESULT: A high diagnostic yield without significant complications was noted. The RCR for nonmedicated patients was 36%. Among all medicated cases, the RCR was 93%. In patients who were given the non-narcotic analgesic ketorolac, the RCR was 96%, compared with 95% in patients not given ketorolac. CONCLUSIONS: A family physician in rural practice was able to attain and sustain a state-of-the-art, reach-the-cecum rate over a 9-year period. This service resulted in a high diagnostic yield, high degree of safety, and satisfactory results for the community. Ketorolac is an effective alternative for patients who may be hypersensitive to narcotic analgesia/sedation. 相似文献
994.
SP Gopinath CS Robertson CF Contant C Hayes Z Feldman RK Narayan RG Grossman 《Canadian Metallurgical Quarterly》1994,57(6):717-723
Early experience with continuous monitoring of jugular venous oxygen saturation (SjvO2) suggested that this technology might allow early identification of global cerebral ischaemia in patients with severe head injury. The purpose of the present study was to examine the relationship between episodes of jugular venous desaturation and neurological outcome. One hundred and sixteen severely head-injured patients had continuous monitoring of SjvO2 during days 1-5 after injury. Episodes of jugular venous desaturation (SjvO2 < 50% for more than 10 minutes) were prospectively identified, and the incidence of desaturation was correlated with neurological outcome: 77 episodes of desaturation occurred in 46 of the 116 patients; 27 had one episode and 19 had multiple episodes of desaturation. The causes of these episodes were systemic (n = 36), cerebral (n = 35), or both (n = 6). Most of the episodes were less than 1 hour in duration, and it is probable that many of them would not have been detected without continuous measurement of SjvO2. Episodes of desaturation were most common on day 1 after injury, and were twice as common in patients with a reduced cerebral blood flow as in patients with a normal or elevated cerebral blood flow. The occurrence of jugular venous desaturation was strongly associated with a poor neurological outcome. The percentage of patients with a poor neurological outcome was 90% with multiple episodes of desaturation and 74% in patients with one desaturation, compared to 55% in patients with no episodes of desaturation. When adjusted for all co-variates that were found to be significant, including age, Glasgow coma score, papillary reactivity, type of injury, lowest recorded cerebral perfusion pressure, and highest recorded temperature, the incidence of desaturation remained significantly associated with a poor outcome. Although a cause and effect relationship with outcome cannot be established in this study, the data suggest that monitoring SvO2 might allow early identification and therefore treatment of many types of secondary injury to the brain. 相似文献
995.
996.
Choroidal nevi are found on routine fundus evaluations in 1% to 2% of patients. It is felt that these usually benign lesions are the precursors of choroidal malignant melanomas. The incidence of choroidal malignant melanoma in the United States is approximately 6 cases per 1 million persons per year. Diagnosis is multifactorial, based on the tumor's funduscopic, angiographic, and ultrasonographic appearance. Once a melanoma is diagnosed in a patient, a complete metastatic workup is performed. A small tumor is observed for change. Medium-sized tumors are treated with radioactive plaque therapy, external beam radiation, or enucleation. Large tumors are treated with enucleation with or without external beam radiation. Studies are underway to establish the optimum form of treatment. 相似文献
997.
998.
CF Lim R Docter TJ Visser EP Krenning B Bernard H van Toor M de Jong G Hennemann 《Canadian Metallurgical Quarterly》1993,76(5):1165-1172
We investigated bilirubin and oleic acid as causes of low plasma T3 in nonuremic critically ill patients with gross changes in serum thyroid hormone levels (T4, < or = 60; T3, < or = 1.1; rT3, > or = 0.45 nmol/L) and elevated bilirubin concentrations (> or = 33 mumol/L). Iodide production from [125I]T4 was inhibited by 42% when rat hepatocytes in primary cultures were incubated with 10% serum from these patients. The mean serum concentration of albumin was reduced by 41%, while the concentrations of bilirubin and nonesterified fatty acids (NEFA) were increased by 2022% and 115%, respectively, in the patients. The molar ratios of bilirubin/albumin and NEFA/albumin in the patients were 0.42 and 3.18, respectively. Addition of oleic acid (50-400 mumol/L) and bilirubin (3-130 mumol/L) to 10% normal human serum (albumin, 70 mumol/L; NEFA, 54 mumol/L; bilirubin, 1.1 mumol/L) progressively inhibited the production of iodide by rat hepatocytes. The decreased iodide production was presumed to be caused by inhibition of T4 transport into hepatocytes. The deiodination of rT3 by rat liver microsomes was unaltered by free bilirubin and free oleic acid concentrations up to 0.1 mumol/L. These free concentrations are at least 1 order of magnitude higher than that attained in nonthyroidal illness. The inhibition of iodide production by the sera of critically ill patients (n = 12) was significantly correlated with the molar ratios of bilirubin/albumin (r = 0.72; P < 0.01) and NEFA/albumin (r = 0.58; P < 0.05). Extensive dialysis or treatment of the sera with charcoal did not completely remove the inhibitory activity on iodide production. Serum concentrations of indoxyl sulfate, 3-carboxy-4-methyl-5-propyl-2-furan propanoic acid, and hippuric acid in the critically ill patients (other known T4 transport inhibitors into hepatocytes) were similar to those in the normal subjects. This study together with the well known effects of carbohydrate on T3 neogenesis suggest that elevated bilirubin and NEFA and the low albumin level in non-uremic critical illness may be at least partly responsible for the T4 transport inhibition in T3-producing tissues (e.g. the liver) and, thus, the low plasma T3 levels in these critically ill patients. The question of whether inhibitors of T4 transport into the hepatocytes are also present in other patients with nonthyroidal illness who show only mild changes in thyroid hormone levels and have low concentrations of bilirubin and NEFA remains to be determined. 相似文献
999.
N de Vries CF Prinsen EB Mensink PL van Riel MA van't Hof LB van de Putte 《Canadian Metallurgical Quarterly》1993,52(5):327-331
OBJECTIVE: In rheumatoid arthritis (RA) genetic factors influence susceptibility to disease and progression. Identifying these genetic factors may give more insight into the aetiology and pathogenesis of this disease. Furthermore, if these genetic markers can predict progression in an early stage of disease, timely institution of more aggressive treatment in patients with a bad prognosis may help to prevent joint damage. Several studies have shown that HLA-DRB1 alleles are associated with RA, whereas others have indicated that genes not linked to the HLA complex are also involved. Candidates for such genes are the T cell receptor (TCR) alpha/beta genes. METHODS: The association of a polymorphism in a TCR beta chain variable region gene (TCR-V beta 8) with both risk for RA and radiographic progression of joint disease was analysed after a three year follow up. A cohort of 118 white patients with a duration of disease shorter than one year at entry, and 110 white controls were typed for this (BamHI) TCR-V beta 8 polymorphism. RESULTS: The distribution of the two alleles, 2.0 and 23.0 kb, was identical in patients and controls. Radiographic progression (modified Sharp method) after a three year follow up, studied in 111 patients, was significantly less in the group possessing the 2.0 kb allele (p = 0.03). CONCLUSION: This does not confirm the reported association of the (BamHI) TCR-V beta 8 2.0 kb allele with RA. By contrast with previous findings in smaller studies, in the present study this 2.0 kb allele was protective against radiographic progression. Because well known prognostic variables in RA were corrected for, the findings indicate that the TCR-V beta 8 polymorphism studied is a new prognostic marker for this disease. 相似文献
1000.
L Perlaky Y Saijo RK Busch CF Bennett CK Mirabelli ST Crooke H Busch 《Canadian Metallurgical Quarterly》1993,8(1):3-14
Using a rat model of short- (4 weeks) and long-term (10 weeks) ascending aortic banding and debanding, we examined the relationship between coronary dilator reserve and morphological vascular changes. After 4 or 10-week banding, in vivo systolic left ventricular pressure and ventricular wt/body wt ratio increased to a similar level, compared with controls. The coronary dilator reserve measured in an isolated heart preparation decreased similarly in the two banded groups, compared with controls. The ratios of medial to luminal area and perivascular collagen to luminal area in coronary microvessels increased in the banded groups. At 4 weeks after debanding, cardiac hypertrophy regressed to the control level, and the duration of banding did not alter the extent of the regression. The coronary dilator reserve normalized in the group debanded after 4-week banding, but did not regress in the group debanded after 10-week banding. In both of the debanded groups, the hypertrophied media regressed completely. The increased perivascular collagen regressed almost completely in the group debanded after 4-week banding, but remained greater in the group debanded after 10-week banding than in the controls. From these results, we conclude that (i) the regression of medial hypertrophy does not always improve the decreased coronary dilator reserve, and (ii) the vascular fibrosis may be the major cause of the irreversibility of decreased coronary dilator reserve in long-term cardiac hypertrophy. 相似文献