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41.
AIM: Appendiceal air has been reported as both a sign of appendicitis and of a normal appendix both at plain radiography and computed tomography (CT). It is the aim of this investigation to determine the prevalence, range of appearances, and significance of appendiceal and peri-appendiceal air at CT. PATIENTS AND METHODS: Appendiceal CT scans of 100 patients with proven appendicitis and 100 patients with a normal appendix were reviewed for the presence of appendiceal and peri-appendiceal air. All cases were correlated with surgical and pathological findings or clinical follow-up. RESULTS: In 100 CT cases of appendicitis, appendiceal and/or peri-appendiceal air was present in one or more forms in 31% of cases. When present, it appeared as intraluminal air bubbles (38.7%) or air-fluid levels (22.6%), appendolith air (41.9%), intramural air (16.1%), peri-appendiceal air bubbles (12.9%), or extraluminal air-fluid level(s) (29.0%). Intramural and extraluminal air correlated with perforation in 60% and 100%, respectively. In 100 CT cases of a normal appendix, air was present in 57%. It was always intraluminal and appeared as small bubbles of air (52.6%), a tubular-shaped air collection (43.9%), or as an air-fluid level (3.5%). The appendiceal lumen was either airless (43%), or minimally (32%), moderately (18%), or completely filled with air (7%). CONCLUSION: Air is a common finding at appendiceal CT in both the normal and inflamed appendix. Intraluminal air is seen in both appendicitis and normal appendices, and cannot be presumed to indicate a patent lumen and thus a normal appendix. Appendolith, intramural and peri-appendiceal air appear diagnostic of appendicitis. 相似文献
42.
Recent evidence has indicated that physician judgments of patients can be influenced by contextual factors. This study examined three contextual factors relevant to hypothetical patients with low back pain, using vignettes that were varied in a 2 x 2 x 2 factorial design: level of reported pain (high vs low), level of supporting medical evidence (high vs low), and the valence of the physician-patient interaction (positive vs negative). Perceived levels of pain, disability, emotional distress, and somatic preoccupation were rated by internists after reading a vignette. Ratings of pain and disability were lower for patients without supporting medical evidence; ratings of distress, somatic preoccupation, and disability were greater for patients who exhibited negative rather than positive affect; internist ratings of pain were lower than patient ratings among patients reporting high levels of pain, while ratings were inflated for patients with low levels of pain. The results suggest that characteristics of both the patient and the situation may influence medical judgments. 相似文献
43.
LS Sheldon JT Keever JM Roberds JB Beach JN Morgan 《Canadian Metallurgical Quarterly》1997,7(1):37-59
Dietary uptake may be a significant pathway of exposure to contaminants. As such, dietary exposure assessments should be considered an important part of the total exposure assessment process. The objective of this work was to develop reliable methods that are applicable to a wide range of base/neutral and carbamate-type pesticides in duplicate diet samples collected as part of dietary exposure assessment studies. The resulting method needed to be sensitive to concentrations below 1 ng/g, accurate and precise, and as simple and cost effective as possible. As a first step, information was gathered on current methods for measuring pesticides in foods. Although the literature methods could serve as a starting point, few had been applied to duplicate diet samples and detection limits were generally high (10 to 100 ng/g). Experimental work was performed to evaluate individual extraction, cleanup, and analysis procedures; link the most promising procedures into analysis methods; and generate performance data on the final method. The final method used Soxhlet extraction with solvent partitioning and gel permeation chromatography cleanup. Gas chromatography/mass spectrometry was used for the analysis of base/neutral pesticides. High performance liquid chromatography analysis was used for the analysis of carbamate pesticides. Results of performance testing showed good accuracy (recovery > 70%), precision (% RSD < 25%), and sensitivity (method detection limits < 1.0 ng/g) for most pesticides targeted for study. 相似文献
44.
OBJECTIVE: The aim of this study was to determine the ovarian volume by transvaginal ultrasonography in a gynecologically healthy population of women using no contraception, using intrauterine contraceptive device, or using oral contraceptive. MATERIALS AND METHOD: The study had a cross-sectional design. The ovaries of 428 women aged 1445 who contacted the family planning clinic in the county of Funen were examined. Most of the statistical analyses were carried out using standard techniques. However polynominal regression analysis was used to model ovarian volumes as a function of the day of cycle. RESULTS: No differences between the volumes of the right and the left ovary were found in any of the groups. Significant differences were found between the ovarian volumes of the three groups. The ovarian volumes were found to be largest in women using intrauterine contraceptive device, lesser in women using no contraception and smallest in women using oral contraception. A significant difference was found of the ovarian volumes throughout the menstrual cycle in women who were not using oral contraception. The ovarian volumes did not change throughout the menstrual cycle in women using oral contraception. In women not using oral contraception the largest ovary increased in volume from the start of the cycle to day 19, thereafter the volume declined. No evidence of any change of volume over the menstrual cycle was found in the smallest ovary and, for women using oral contraception, both ovaries. There was no correlation between age, height, weight, parity, and ovarian volume in any of the groups. CONCLUSION: The ovarian volumes, in gynecologically healthy women using intrauterine contraceptive device, are larger than in women using no contraception. It appears that oral contraception reduces the volumes of both ovaries in all phases of the menstrual cycle to equal levels. 相似文献
45.
Results of allogeneic bone marrow transplants for leukemia using donors other than HLA-identical siblings 总被引:1,自引:0,他引:1
R Szydlo JM Goldman JP Klein RP Gale RC Ash FH Bach BA Bradley JT Casper N Flomenberg JL Gajewski E Gluckman PJ Henslee-Downey JM Hows N Jacobsen HJ Kolb B Lowenberg T Masaoka PA Rowlings PM Sondel DW van Bekkum JJ van Rood MR Vowels MJ Zhang MM Horowitz 《Canadian Metallurgical Quarterly》1997,15(5):1767-1777
PURPOSE: To compare outcomes of bone marrow transplants for leukemia from HLA-identical siblings, haploidentical HLA-mismatched relatives, and HLA-matched and mismatched unrelated donors. PATIENTS: A total of 2,055 recipients of allogeneic bone marrow transplants for chronic myelogenous leukemia (CML), acute myelogenous leukemia (AML), and acute lymphoblastic leukemia (ALL) were entered onto the study. Transplants were performed between 1985 and 1991 and reported to the International Bone Marrow Transplant Registry (IBMTR). Donors were HLA-identical siblings (n = 1,224); haploidentical relatives mismatched for one (n = 238) or two (n = 102) HLA-A, -B, or -DR antigens; or unrelated persons who were HLA-matched (n = 383) or mismatched for one HLA-A, -B, or -DR antigen (n = 108). HLA typing was performed using serologic techniques. RESULTS: Transplant-related mortality was significantly higher after alternative donor transplants than after HLA-identical sibling transplants. Among patients with early leukemia (CML in chronic phase or acute leukemia in first remission), 3-year transplant-related mortality (+/-SE) was 21% +/- 2% after HLA-identical sibling transplants and greater than 50% after all types of alternative donor transplants studied. Among patients with early leukemia, relative risks of treatment failure (inverse of leukemia-free survival), using HLA-identical sibling transplants as the reference group, were 2.43 (P < .0001) with 1-HLA-antigen-mismatched related donors, 3.79 (P < .0001) with 2-HLA-antigen-mismatched related donors, 2.11 (P < .0001) with HLA-matched unrelated donors, and 3.33 (P < .0001) with 1-HLA-antigen-mismatched unrelated donors. For patients with more advanced leukemia, differences in treatment failure were less striking: 1-HLA-antigen-mismatched relatives, 1.22 (P = not significant [NS]); 2-HLA-antigen-mismatched relatives, 1.81 (P < .0001); HLA-matched unrelated donors, 1.39 (P = .002); and 1-HLA-antigen-mismatched unrelated donors, 1.63 (P = .002). CONCLUSION: Although transplants from alternative donors are effective in some patients with leukemia, treatment failure is higher than after HLA-identical sibling transplants. Outcome depends on leukemia state, donor-recipient relationship, and degree of HLA matching. In early leukemia, alternative donor transplants have a more than twofold increased risk of treatment failure compared with HLA-identical sibling transplants. This difference is less in advanced leukemia. 相似文献
46.
JA McCrohon WA Walters JT Robinson RJ McCredie L Turner MR Adams DJ Handelsman DS Celermajer 《Canadian Metallurgical Quarterly》1997,29(7):1432-1436
OBJECTIVES: We sought to assess whether high dose estrogen treatment is associated with enhanced arterial reactivity in genetic males. BACKGROUND: Although estrogens have been shown to enhance arterial reactivity in women, and are thereby thought to confer cardiovascular benefit, the vascular effects of long-term estrogen therapy in genetic males is unknown. METHODS: We studied the arterial physiology of 30 genetic males--15 male to female transsexuals receiving long-term high dose estrogen therapy and 15 healthy male control subjects matched for age, smoking history and vessel size. Using external vascular ultrasound, brachial artery diameter was measured at rest, after flow increase (causing endothelium-dependent dilation [EDD]) and after nitroglycerin (GTN), an endothelium-independent dilator. Blood pressure, cholesterol and testosterone levels were also measured in each subject. RESULTS: Total testosterone and free testosterone index levels were lower in the transsexuals compared with the control subjects (p < 0.001). In contrast, EDD was significantly higher in the transsexuals than in the control males (mean [+/-SD] 7.1 +/- 3.1% vs. 3.2 +/- 2.8%, p = 0.001), as was the GTN response (21.2 +/- 6.7% vs. 14.6 +/- 3.3%, p = 0.002). Total and high density lipoprotein cholesterol, blood pressure levels and baseline vessel size were similar in the two groups. On multivariate analysis, enhanced EDD was associated independently with estrogen therapy (p = 0.02) and with low total cholesterol (p = 0.04). An enhanced GTN response was also significantly associated with estrogen therapy (p = 0.03). CONCLUSIONS: Long-term treatment with high dose estrogens is associated with enhanced arterial reactivity in genetic males, which may be due to the effects of estrogen excess or androgen deprivation, or both. 相似文献
47.
This study was designed to investigate the effect of retaining coronal tooth substance on the performance of post-retained core materials, and to compare the fracture resistance of the system with an intact tooth prepared to similar dimensions. Ten teeth restored with post-retained silver amalgam, and 10 teeth restored with silver-glass cermet, all with a retained single wall of coronal tooth substance, were compared with 10 unrestored teeth prepared to similar dimensions when subjected to a shearing load. The results showed no statistically significant difference between the unrestored teeth and those restored with a silver-glass cermet. Whilst the teeth restored with silver amalgam had a significantly higher fracture resistance (P > 0.01) there was greater tendency to root fracture. 相似文献
48.
The effects of chronic administration of [D-Pen2, D-Pen5]enkephalin and [D-Ala2, Glu4]deltorphin II, the selective agonists of the delta 1- and delta 2-opioid receptors, on the binding of [3H]MK-801, a noncompetitive antagonist of the N-methyl-D-aspartate receptor, were determined in several brain regions of the mouse. Male Swiss-Webster mice were injected intracerebroventricularly (i.c.v.) with [D-Pen2, D-Pen5]enkephalin or [D-Ala2, Glu4]deltorphin II (20 micrograms/mouse) twice a day for 4 days. Vehicle injected mice served as controls. Previously we have shown that the above treatment results in the development of tolerance to their analgesic activity. The binding of [3H]MK-801 was determined in brain regions (cortex, midbrain, pons and medulla, hippocampus, striatum, hypothalamus and amygdala). At 5 nM-concentration, the binding of [3H]MK-801 was increased in cerebral cortex, hippocampus, and pons and medulla of [D-Pen2, D-Pen5]enkephalin treated mice. In [D-Ala2, Glu4]deltorphin II treated mice, the binding of [3H]MK-801 was increased in cerebral cortex and hippocampus. The changes in the binding were due to increases in the Bmax value of [3H]MK-801. It is concluded that tolerance to delta 1- and delta 2-opioid receptor agonists is associated with up-regulation of brain N-methyl-D-aspartate receptors, however, some brain areas affected differ with the two treatments. The results are consistent with the recent observation from this laboratory that N-methyl-D-aspartate receptors antagonists block tolerance to the analgesic action of delta 1- and delta 2-opioid receptor agonists. 相似文献
49.
DM Kriegsman DJ Deeg JT van Eijk BW Penninx AJ Boeke 《Canadian Metallurgical Quarterly》1997,51(6):676-685
STUDY OBJECTIVES: To determine whether disease specific characteristics, reflecting clinical disease severity, add to the explanation of mobility limitations in patients with specific chronic diseases. DESIGN AND SETTING: Cross sectional study of survey data from community dwelling elderly people, aged 55-85 years, in the Netherlands. PARTICIPANTS AND METHODS: The additional explanation of mobility limitations by disease specific characteristics was examined by logistic regression analyses on data from 2830 community dwelling elderly people. MAIN RESULTS: In the total sample, chronic non-specific lung disease, cardiac disease, peripheral atherosclerosis, diabetes mellitus, stroke, arthritis and cancer (the index diseases), were all independently associated with mobility limitations. Adjusted for age, sex, comorbidity, and medical treatment disease specific characteristics that explain the association between disease and mobility mostly reflect decreased endurance capacity (shortness of breath and disturbed night rest in chronic non-specific lung disease, angina pectoris and congestive heart failure in cardiac disease), or are directly related to mobility function (stiffness and lower body complaints in arthritis). For atherosclerosis and diabetes mellitus, disease specific characteristics did not add to the explanation of mobility limitations. CONCLUSIONS: The results provide evidence that, to obtain more detailed information about the differential impact of chronic diseases on mobility, disease specific characteristics are important to take into account. 相似文献
50.
G Wu PK Davis NE Flynn DA Knabe JT Davidson 《Canadian Metallurgical Quarterly》1997,127(12):2342-2349
This study was conducted to determine whether endogenous synthesis of arginine plays a role in regulating arginine homeostasis in postweaning pigs. Pigs were fed a sorghum-based diet containing 0. 98% arginine and were used for studies at 75 d of age (28.4 kg body weight). Mitochondria were prepared from the jejunum and other major tissues for measuring the activities of Delta1-pyrroline-5-carboxylate (P5C) synthase and proline oxidase (enzymes catalyzing P5C synthesis from glutamate and proline, respectively) and of ornithine aminotransferase (OAT) (the enzyme catalyzing the interconversion of P5C into ornithine). For metabolic studies, jejunal enterocytes were incubated at 37 degrees C for 30 min in Krebs-Henseleit bicarbonate buffer containing 2 mmol/L L-glutamine, 2 mmol/L L-[U-14C]proline, and 0-200 micromol/L gabaculine (an inhibitor of OAT). The activities of P5C synthase, proline oxidase and OAT were greatest in enterocytes among all of the tissues studied. Incubation of enterocytes with gabaculine resulted in decreases (P < 0.05) in the synthesis of ornithine and citrulline from glutamine and proline. When gabaculine was orally administered to pigs (0.83 mg/kg body weight) to inhibit intestinal synthesis of citrulline from glutamine and proline, plasma concentrations of citrulline (-26%) and arginine (-22%) decreased (P < 0.05), whereas those of alanine (+21%), ornithine (+17%), proline (+107%), taurine (+56%) and branched-chain amino acids (+21-40%) increased (P < 0.05). On the basis of dietary arginine intake and estimated arginine utilization, the endogenous synthesis of arginine in the 28-kg pig provided >/=50.2% of total daily arginine requirement. Taken together, our results suggest an important role for endogenous synthesis of arginine in regulating arginine homeostasis in postweaning growing pigs, as previously shown in neonatal pigs. 相似文献