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991.
992.
We retrospectively reviewed 16 patients who presented to hospitals with orthopaedic complaints. Twelve patients experienced initial symptoms in the extremities and four patients had back pain. The leukocyte count was elevated in one patient, decreased in two patients, and normal in 13 patients. On radiographic examination, osteopenia was observed in 10 patients, osteolytic lesions were observed in five, and pathologic fractures were observed in five. Because the initial presentation of patients with leukemia often involves the musculoskeletal system, orthopaedists need to recognize the symptoms of this disease to avoid misdiagnosis and to expedite the initiation of appropriate potentially lifesaving treatment.  相似文献   
993.
Magnetic resonance (MR) imaging is an important diagnostic tool for neurosurgical diseases but susceptibility artifacts caused by biomaterial instrumentation frequently causes difficulty in visualizing postoperative changes. The susceptibility artifacts caused by neurosurgical biomaterials were compared quantitatively by 0.5, 1.5, and 3.0 Tesla MR imaging. MR imaging of uniform size and shape of pieces ceramic (zirconia), pure titanium, titanium alloy, and cobalt-based alloy was performed at 0.5, 1.5, and 3.0 Tesla. A linear region of interest was defined across the center of the biomaterial in the transverse direction, and the susceptibility artifact diameter was calculated. Susceptibility artifacts developed around all biomaterials at all magnetic field strengths. The artifact diameters caused by pure titanium, titanium alloy, and cobalt-based alloy increased in the order of 0.5, 1.5, to 3.0 Tesla magnetic fields. The artifact diameter of ceramic was not influenced by magnetic field strength, and was the smallest of all biomaterials at all magnetic field strengths. The artifacts caused by biomaterials except ceramic increase with the magnetic field strength. Ceramic instrumentation will minimize artifacts in all magnetic fields.  相似文献   
994.
PURPOSE: We investigated the risk factors having an impact on the achievement of stone-free status and on the success rate, as well as on the likelihood of recurrence, in patients undergoing shockwave lithotripsy. PATIENTS AND METHODS: We evaluated the characteristics and outcomes of 3023 patients (3254 renal units) with upper urinary-tract stones who underwent SWL at the Funabashi Clinic over a 13-year period. We assessed the stone-free and success rates for 2844 patients (3061 renal units) 3 months post-SWL. We also determined the recurrence rate for the 1078 patients (1139 renal units) who had achieved stone-free status at that time. RESULTS: Overall, stone-free status was achieved in 65.1% of patients, and the success rate was 85.7%. There were significant differences in the stone-free rates depending on patient age, history of urolithiasis, and presence of pyuria before SWL, as well as the number, location, size, and composition of the stones. Stones recurred in 326 of 1139 renal units (28.6%) during a mean follow-up of 36 months. The recurrence rates were 7.5%, 24.1%, and 33.0% after 1, 3, 5 years, respectively. Multiple stones, a history of urolithiasis, and stones located in the kidney or both kidneys plus the ureter significantly influenced recurrence. Multivariate analysis demonstrated that multiple stones were most significantly related to recurrence. CONCLUSION: Treatment with SWL has a low morbidity and high effectiveness. The number and location of stones and a history of urolithiasis significantly influence recurrence. Further studies of prophylactic therapy are required, especially for patients with these factors.  相似文献   
995.
996.
BACKGROUND: The present study was undertaken to demonstrate the deposition of immunoglobulins or complements in formaldehyde-fixed and paraffin-embedded renal biopsy tissues through the unmasking of antigens with microwave treatment plus protease digestion or trypsin digestion. METHODS: Biopsy samples from patients with IgA nephritis (n = 7), lupus nephritis (7), membranous nephropathy (7) and mesangiocapillary glomerulonephritis (3) were used. Antigen unmasking was performed with (i) microwave treatment plus protease digestion for 10, 30 or 60 min, or (ii) digestion with 0.25% trypsin for 60 or 120 min. RESULTS: Microwave treatment plus protease digestion for 30 or 60 min and trypsin digestion for 120 min provided good results for the unmasking of immunoglobulins in glomeruli with structural preservation. The IgA deposits in IgA nephritis and IgG deposits in lupus nephritis and membranous nephropathy were clearly revealed in more than 80% of cases by both pretreatments. Microwave treatment plus protease digestion for 30 min revealed the deposition of C3 in all cases of mesangiocapillary glomerulonephritis and lupus nephritis and was superior to trypsin digestion. Characteristic patterns of C3 deposition were observed for these forms of glomerulonephritis, although C3 deposits in membranous nephropathy were detected in only 50% of cases. It was not possible to unmask all of the antigens in the glomeruli, especially those with weak immunofluorescence. CONCLUSION: Microwave treatment plus protease digestion is effective for the unmasking of antigens in paraffin sections and as useful for the diagnosis of immune-mediated glomerulonephritis as trypsin digestion.  相似文献   
997.
998.
To investigate additional endpoints for screening of endocrine disruptors in birds, effects of 17beta-estradiol (E2) on one-generation reproduction in the Japanese quail (Coturnix japonica) were assessed. Pairs of the 10-week-old Japanese quail were fed a low-phytoestrogen diet containing E2 at 0 (control), 10, 100, and 1,000 ppm for six weeks. In the E2 100- and 1,000-ppm groups, the parental quail represented marked toxic changes including high mortality, decreased food consumption, decreased gonad weights, gross and histologic toxic changes in the reproductive and other organs, and inhibition of the reproduction. However, no adverse effects were observed in the parental quail from the E2 10-ppm group. In the parental males, serum vitellogenin (VTG) concentrations were increased significantly in the E2 10-ppm group, disclosing that serum VTG concentration is one of the highly sensitive endpoints for evaluating estrogenic endocrine activities. In the E2 10-ppm group, number of eggs laid, number of eggs with abnormalities, eggshell strength and thickness, fertility, early and late viabilities of embryos, normal hatchling rate, and clinical signs, mortality, viability, and body weight of chicks at 14 d of age were not affected. However, histopathology of the chicks in the E2 10-ppm group revealed meaningful morphological changes in the reproductive organs, such as cystic dilatation of seminiferous tubules, increased interstitial cells in the testis, and decreased theca cells in the ovary. The present study suggests that serum VTG concentration in the parental quail and histopathology of reproductive organs in the offspring are sensitive endpoints and are useful as additional endpoints in the avian one-generation reproduction test using the Japanese quail for evaluating estrogenic endocrine-disrupting effects.  相似文献   
999.
BACKGROUND: Few studies have examined the validity of administering tuberculosis control measures based on tuberculin skin test (TST) erythema measurement. The present study aimed to clarify the relationship between the erythema and the induration seen following TST and to evaluate the validity of diagnosing tuberculosis infection based on the erythema following TST in school-aged contacts who had been vaccinated with bacillus Calmette-Guérin (BCG) in infancy. METHODS: A 56-month longitudinal study from January 1999 through September 2003 followed 566 junior high school students in Kochi City who were contacts of an infectious tuberculosis case. To evaluate the diagnostic accuracy of the erythema and induration following TST of the contacts, false-positive and false-negative TST results were noted. RESULTS: The natural logarithm of the erythematous response size was linearly related to the induration size. When the size of the erythematous response was used to determine the presence of tuberculosis infection, the proportion of infected children increased with increasing exposure to the index case. When the TST results in the contact investigation were interpreted together with the change in the size of the erythematous response from that observed at the regular school-entry checkup, false positive test results were avoidable among the students who had a large erythematous response after the contact investigation TST, but whose response was only slightly larger than their erythematous response following the school-entry TST. Among the students whose TST results were negative, 1.9% developed tuberculosis. CONCLUSION: Both erythema and induration measurement were equally effective for identifying tuberculosis infection in schoolchildren vaccinated with BCG.  相似文献   
1000.
Objective: This study was undertaken to review our experience of mitral valve replacement in children under 3 years of age. Methods: Between January 1990 and May 2004,18 patients under 3 years of age underwent a total of 20 mitral valve replacements using a bileaflet mechanical prosthetic valve. There were 9 males and 11 females. The age at surgery ranged from 3 months to 3 (mean=1.02±0.72) years and body weight varied between 3.4 and 13.2 (mean=7.08±2.74) kg. Results: There were 4 early and 2 late deaths, and these occurred in severe cases aged less than 1 year of age. Re-replacement of mitral valve was required in 3 patients (valve thrombosis in 2 and pannnus formation in 1). Orifice size of the implanted prosthesis (OS) as compared with the predicted normal size of the mitral valve (NS) was well correlated with maximum transprosthetic flow velocity estimated by Doppler echocardiography. In this study, the OS/NS>0.65 was maintained in all patients, and none required re-replacement because of prosthesis-patient mismatch. Conclusion: Patients less than 1 year of age had significant mortality and morbidity. The results were satisfactory in the remainder (1–3 years). During this follow-up period, none required re-replacement due to somatic growth, but it will be an unavoidable problem in the future. The OS/NS, which can be checked with a regular physical examination, may serve as a guide to determine the most appropriate timing for the second surgery.  相似文献   
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