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41.
42.
PM Roger V Mondain MC St Paul F Peyrade A Pesce JG Fuzibet JF Michiels P Dellamonica 《Canadian Metallurgical Quarterly》1998,27(32):1617-1620
OBJECTIVE: There is substantial evidence demonstrating the aggravating effect of human immunodeficiency virus (HIV) infection on the progression of chronic hepatitis C virus (HCV) infection. There is however, little data on the affect of certain factors which could affect liver pathology findings in patients with concomitant HIV infection such as the duration of HIV infection or T-cell subpopulation counts. We examined pathology findings in patients with concomitant HIV and HCV infections to determine the impact of immunodepression. PATIENTS AND METHODS: We reviewed liver pathology data collected in patients with concomitant HIV and HCV infections grouping patients according to severity of the liver pathology: group 1 = cirrhosis or active hepatitis; group 2 = minimally active hepatitis or histologically normal liver. Transparietal liver biopsies were obtained for the work-up of viral hepatitis or because of long-term unexplained fever or suspected lymphoma. Epidemiological and biological data were obtained from medical files. The duration of the liver disease was estimated from the date of exposure to risk of immunodepression as determined by the peripheral CD4+ and CD8+ counts. All pathology specimens were read by two pathologists who established the Knodell score for each patient. RESULTS: Fifty patients were included: 23 were classed in group 1 and 28 in group 2. The Knodell score was significantly different between the two groups, 11 +/- 4 and 4 +/- 3 respectively (p < 0.0001). Disease duration was similar for the two groups: mean 8 years. Mean CD4+ count was significantly higher in group 1: 312/mm3 versus 110/mm3 for group 2 (p = 0.0057); as was the mean CD8+ count (758/mm3 versus 360/mm3, p = 0.0013). For the entire study population, there was a significantly negative correlation (p < 0.05) between the Knodell score and the CD4+ count (r = 0.31) and for the CD8+ count (r = 0.41). CONCLUSION: HCV-related liver pathology in patients co-infected with HIV depends on the level of immunodepression. CD8+ counts are better correlated with pathology findings than with CD4+ counts. 相似文献
43.
Surgical pathologists are cautioned against the misinterpretation of immature dental tissues (dental papillae and follicles) and dental pulp as odontogenic tumors, especially odontogenic myxomas and fibromas. The close histologic similarity of the immature tissues to tumors may require a clinical-radiologic correlation with the histopathologic specimen in order to distinguish the locally aggressive tumors from innocuous dental tissues. 相似文献
44.
The measurement of bone mineral density (BMD) using dual energy X-ray absorptiometry (DXA) provides an indicator of subsequent risk of hip fracture, but because of the significant overlap of measurements obtained from osteoporotic and control groups its predictive power is limited. The radiographic technique of Singh grading for the assessment of femoral osteoporosis utilizes information about the distribution of trabecular bundles, but the morphological information available in the DXA image has not previously been analysed. In this study of DXA images from 64 individuals (32 controls and 32 classified as osteoporotic) a subjective grading technique analogous to Singh grading is proposed, and quantitative measurements are made of image features corresponding to two of the categories. Discrimination was assessed using receiver operating characteristic (ROC) curves: the best discrimination was by spinal BMD (Az = 0.85 +/- 0.05) a performance equalled by one of the new parameters; the subjective grading method (Az = 0.79 +/- 0.07) performed as well as measurements of BMD in the femur. These results suggest that although the alternative measures do not improve on the discrimination possible using spinal BMD, morphological information from the hip itself may in the future have a place in the assessment of bone quality. 相似文献
45.
46.
N Georgiou JG Phillips JL Bradshaw R Cunnington E Chiu 《Canadian Metallurgical Quarterly》1997,12(3):386-396
This study aimed to quantify the efficiency and smoothness of voluntary movement in Huntington's disease (HD) by the use of a graphics tablet that permits analysis of movements profiles. In particular, we aimed to ascertain whether a concurrent task (digit span) would affect the kinematics of goal-directed movements. Twelve patients with HD and their matched controls performed 12 vertical zig-zag movements, with both left and right hands (with and without the concurrent task), to large or small circular targets over long or short extents. The concurrent task was associated with shorter movement times and reduced right-hand superiority. Patients with HD were overall slower, especially, with long strokes, and had similar peak velocities for both small and large targets, so that controls could better accommodate differences in target size. Patients with HD spent more time decelerating, especially with small targets, whereas controls allocated more nearly equal proportions of time to the acceleration and deceleration phases of movement, especially with large targets. Short strokes were generally less force inefficient than were long strokes, especially so for either hand in either group in the absence of the concurrent task, and for the right hand is its presence. With the concurrent task, however, the left hand's behavior changed differentially for the two groups; for patients with HD, it became more force efficient with short strokes and even less efficient with long strokes, whereas for controls, it became more efficient with long strokes. Controls may be able to divert attention away from the inferior left hand, increasing its automaticity, whereas patients with HD, because of disease, may be forced to engage even further online visual control under the demands of a concurrent task. Patients with HD may perhaps become increasingly reliant on terminal visual guidance, which indicates an impairment in constructing and refining an internal representation of the movement necessary for its effective execution. Basal ganglia dysfunction may impair the ability to use internally generated cues to guide movement. 相似文献
47.
JG Liese CK Meschievitz E Harzer J Froeschle P Hosbach JE Hoppe F Porter S Stojanov K Niinivaara AM Walker BH Belohradsky 《Canadian Metallurgical Quarterly》1997,16(11):1038-1044
OBJECTIVE: This case-control study investigated the protective efficacy against pertussis of three doses of a two-component acellular pertussis vaccine (manufactured by Biken in Japan) combined with diphtheria and tetanus toxoids (manufactured by Connaught Laboratories in the US) in infants. METHODS: A case-control study was performed in 63 pediatric practices in Germany. Prospective recruitment of 16,780 infants ages 6 to 17 weeks took place between February, 1993, and July, 1994. According to parental choice infants received either Biken acellular pertussis vaccine combined with diphtheria and tetanus toxoids (DTacP) (74.6%) at approximately 2, 4 and 6 months of age, or a licensed German diphtheria-tetanus toxoids-whole cell pertussis vaccine (10.9%), diphtheria-tetanus toxoids vaccine (12.5%) or no vaccine (2.0%). Prospective surveillance of pertussis cases between February, 1993, and May, 1995, was accomplished by culturing all infants < or =2 years of age presenting with cough > or = 7 days. A pertussis case was defined as any cough of 21 days or longer plus a positive Bordetella pertussis culture or household contact exposure. RESULTS: We identified 241 pertussis cases prospectively by 11,017 B. pertussis cultures and 949 controls matched for age were selected from the same pediatric practices. Medical history and demographic and vaccine status data were collected from each case and for four controls. Data were analyzed through conditional logistic regression taking into account individual matching and adjusting for potential confounding variables. DTacP combined with diphtheria and tetanus toxoids vaccine was 82% protective (95% confidence interval, 68 to 90), diphtheria-tetanus toxoids-whole cell pertussis vaccine was 96% protective (95% confidence interval, 78 to 99). Protection against typical B. pertussis infection characterized by paroxysmal cough lasting > or =21 days was 96% (95% confidence interval, 87 to 99) for DTacP and was 97% (95% confidence interval, 79 to 100) for diphtheria-tetanus toxoids-whole cell pertussis vaccine. Adjustment for potentially confounding variables did not change the results significantly. CONCLUSIONS: Three doses of the two-component acellular pertussis vaccine protected infants against pertussis disease during the period before the recommended booster vaccination. For typical pertussis disease as defined by the WHO efficacy was high and similar to that of a licensed German diphtheria-tetanus toxoids-whole cell pertussis vaccine. 相似文献
48.
SH Lisanby DP Devanand MS Nobler J Prudic L Mullen HA Sackeim 《Canadian Metallurgical Quarterly》1996,12(3):156-164
Numerous studies have confirmed the distinct biological behavior of two subsets of prostate cancer diagnosed incidentally after either transurethral resection (TURP) or open prostatectomy for presumed benign prostatic hyperplasia (BPH). Focal, low-grade lesions are associated with a low risk for clinical progression and are designated as stage T1a or A1. These cases have traditionally been managed conservatively with close clinical observation. In contrast, multifocal, high-volume, or high-grade tumors are associated with a more aggressive clinical course and are designated as stage T1b or A2. Early definitive intervention is usually advocated for these latter patients. Therefore, accurate pathological assignment to either stage T1a or T1b is crucial for selection of appropriate management options. A variety of methods for staging patients with incidentally detected prostate cancer have been proposed, including detailed histological analysis, repeat TURP or transurethral biopsy, serial prostate-specific antigen (PSA) analysis, and imaging with either transrectal ultrasound (TRUS) or magnetic resonance (MRI) techniques. This article critically examines the clinical utility of these staging modalities for patients with incidentally detected prostate cancer. 相似文献
49.
Twenty mothers of preterm babies who had survived to 1 year old, were matched for age and parity of the mother and time of birth of the baby, with 20 mothers delivering fullterm. Bone mineral, body composition and anthropometric measurements were obtained for each mother and analysed using paired t-tests. The only significant difference (P < 0.01) between the groups was a lower fat-free mass in the preterm mothers calculated from skinfold thickness measurements. 相似文献
50.
B Rehermann KM Chang JG McHutchison R Kokka M Houghton FV Chisari 《Canadian Metallurgical Quarterly》1996,98(6):1432-1440
Hepatitis C virus (HCV)-specific cytotoxic T lymphocytes (CTL) are present in the peripheral blood and liver of chronically infected patients. The current study was performed to study the relationship between the strength of the CTL response, liver disease severity, and viral load. The results may be summarized as follows: first, using CTL precursor frequency (CTLpf) analysis to quantitate the peripheral blood CTL response, chronically infected patients were less strongly sensitized to a panel of well-defined HCV epitopes than they were to an epitope within the influenza matrix protein. Second, HCV-specific CTLpf did not correlate with disease activity or viral load in the majority of patients on a cross-sectional basis, although it did increase in three patients concomitant with sharp increases in liver disease. Finally, interferon therapy did not enhance the CTLpf against the HCV epitopes studied in these patients, indicating that its antiviral effect is independent of the CTL response. Since the HCV-specific CTLpf in the blood is actually quite low, the CTL may contribute to ongoing liver disease in these patients while being quantitatively inadequate to destroy all of the infected hepatocytes, thereby facilitating HCV persistence and contributing to chronic liver disease. 相似文献