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31.
Linda Wang D.D.S. M.S. Ph.D. Lawrence Gonzaga Lopes D.D.S. M.S. Ph.D. Eduardo Bresciani D.D.S. M.S. José Roberto Pereira Lauris D.D.S. M.S. Ph.D. Rafael Francisco Lia Mondelli D.D.S. M.S. Ph.D. Maria Fidela de Lima Navarro D.D.S. Ph.D. 《Special care in dentistry》2004,24(1):28-33
Atraumetic Restorative Treatment (ART) has been adopted around the world to avoid unnecessary extractions, especially in non-industrialized countries The development of specific glass ionomer cements marketed for the ART technique has contributed to the technical success rate. In this study. Ketac-Molara (3M ESPE. Dental Medzn Germany) was used to restore 150 Class I cavities in 118 Brazilian public school children, aged from 7–12 years. At baseline and at subsequent recalls. CPI probes with a ball-end of 0.5 millimeters (mm) were used to assess loss of restorative material, and photographic color transparencies of restorations were made. After six months. 83 patients returned for follow-up examinations, with 71.8% of their restorations designated as acceptable. After three years. 49 patients with 57 ART-restorations were evaluated, with 21.0% of these restorations graded as acceptable Another 29.8% of their restorations had been replaced by more permanent materials. The main objective of the ART technique is tooth retention; this was achieved for 94.7% of the restored teeth in a high caries risk population who returned for recalls. 相似文献
32.
Sanjay Kakar Kenneth P Batts John J Poterucha Lawrence J Burgart 《Modern pathology》2004,17(7):874-878
Impairment of venous outflow from the liver manifests as zone 3 sinusoidal dilatation and congestion (SDC) in liver biopsy. The spectrum of histologic changes in portal tracts has not been described. We studied liver biopsies from 34 patients with a confirmed diagnosis of venous outflow impairment (VOI). Liver transplant recipients and biopsies with cirrhosis and hepatic neoplasms were excluded. Clinical records were reviewed for laboratory tests and radiographic findings. In all, 19 patients had right heart disease, 13 had classic Budd-Chiari syndrome and two had veno-occlusive disease. Liver chemistry tests showed elevated liver transaminases (n=21; 61.8%), elevated alkaline phosphatase (n=31; 91.2%) and GGT (all 13 cases tested). The elevation in ALT and AST was mild (below 200 U/l in all cases), while alkaline phosphatase (ALP) was elevated above 500 U/l in nine (26.5%) patients and above 1000 U/l in three cases. On biopsy, all cases showed SDC. The portal tracts showed (a) portal expansion with bile ductular proliferation (n=16; 47.1%) accompanied by lymphoplasmacytic infiltrate (n=10), lymphocytic cholangitis (n=3) and portal or periportal fibrosis (n=11), (b) Portal and/or periportal fibrosis without ductular proliferation (n=3; 8.8%) or (c) Normal portal tracts (n=15; 44.1%). The combination of elevated ALP and bile ductular changes on biopsy suggested chronic bile duct disease. Ultrasound/CT scan evaluation of bile ducts in 26 patients showed no biliary tree abnormality. Antimitochondrial antibody testing in eight cases also yielded negative results. In conclusion, bile ductular proliferation, portal inflammation and portal-based fibrosis are commonly seen in liver biopsies of patients with VOI even in the absence of bile duct disease. These changes are often accompanied by elevated ALP and GGT and can lead to the suspicion of chronic biliary disease. In the absence of demonstrable abnormalities in the biliary tree, these changes can be attributed to venous outflow impairment. 相似文献
33.
Shreyasee Amin B Lawrence Riggs Elizabeth J Atkinson Ann L Oberg L Joseph Melton Sundeep Khosla 《Journal of bone and mineral research》2004,19(7):1075-1083
The role of the IGFs and IGFBPs on age-related changes in BMD in adult men and women is not well understood. Studying an age-stratified community based sample of 344 men and 276 women, we found higher IGFBP-2 levels to be associated with lower BMD. IGFBP-2, which increases with age in both men and women, was the strongest, most consistent predictor of BMD among the IGF/IGFBPs studied. INTRODUCTION: Insulin-like growth factors (IGFs) and their binding proteins (IGFBPs) are important regulators of tissue growth and metabolism, but their association with BMD in adult men and women is controversial. MATERIALS AND METHODS: In an age-stratified, random sample of the community population, we examined the role of serum levels of IGF-I, IGF-II, and IGFBP-1, -2, and -3 on BMD of the proximal femur (total hip), lateral spine, midshaft, and ultradistal radius as measured by DXA. We explored the association before and after adjustment for potential confounders, including age, bioavailable estradiol and testosterone, sex hormone binding globulin (SHBG), and measures of total fat and skeletal muscle mass. RESULTS: We studied 344 men (age, 23-90 years) and 276 women (age, 21-93 years; 166 postmenopausal) not on hormone replacement or oral contraceptives. In both men and women, IGF-I and IGFBP-3 levels fell with advancing age, whereas IGFBP-2 levels tended to rise with age. There was an inverse association of IGFBP-2 with BMD at most skeletal sites in men and both premenopausal and postmenopausal women, whereas lower IGF-I and IGFBP-3 were associated with lower BMD in men and postmenopausal women only. Lower IGF-II was associated with lower BMD in men only. There were no associations between IGFBP-1 and BMD in either sex. After adjustment for age, in most cases, we found no further associations between IGF-I, IGF-II, or IGFBP-3 and BMD. In contrast, after age adjustment, higher IGFBP-2 remained a predictor of lower BMD in men and postmenopausal women at all sites except for the lateral spine (for men: r = -0.21, -0.20, and -0.19, all p < 0.001; and for postmenopausal women: r = -0.34, -0.24, and -0.25, all p < 0.01, for the total hip, midshaft, and ultradistal radius, respectively). IGFBP-2 remained an independent negative predictor of BMD in men, postmenopausal women, and all women combined after additional adjustment for bioavailable sex steroids, but not at all sites after adjustment for SHBG and muscle mass. In premenopausal women, IGFBP-2 had similar associations as seen in postmenopausal women, but they were weaker and not statistically robust. CONCLUSIONS: Among the IGF/IGFBPs in our study, IGFBP-2 was a key negative predictor of BMD among men and women, particularly postmenopausal women. Our findings suggest a potential role of the IGF/IGFBP system in regulating bone loss in aging men and women and identify a previously under-recognized, potentially deleterious role for IGFBP-2, a known inhibitor of IGF action that increases with age in both sexes. Whether the action of the IGF/IGFBP system on bone metabolism is mediated partly through its effects on muscle mass or SHBG deserves further study. 相似文献
34.
Lih-Heng Tang Joseph A. Buckwalter Lawrence C. Rosenberg 《Journal of orthopaedic research》1996,14(2):334-339
Previous work has shown that alterations in proteoglycan aggregates are among the first changes detected with aging, disuse, and degeneration of articular cartilage, yet the cause or causes of these alterations remain unknown. To determine if differences in link protein concentration can explain alterations in the assembly, size, and stability of articular cartilage proteoglycan aggregates, we isolated proteoglycan monomer (aggrecan) and link protein from adult bovine articular cartilage and then assembled proteoglycan aggregates from aggrecan and 0.8% hyaluronan relative to aggrecan weight, in the presence of 0, 2, 4, 6, 8, 10, 15, and 20% concentrations of link protein relative to aggrecan weight. We determined the amount, sedimentation coefficient, and stability of the aggregates by analytical ultracentrifugation and measured their dimensions by electron microscopy with use of the monolayer technique. Increased aggregate size, as determined by ultracentrifugation, was directly correlated with an increased number of aggrecans per aggregate and with increased hyaluronan length, as determined by electron microscopy. The concentration of link protein significantly influenced aggregation: concentrations of 6–8% produced maximum aggregation, aggregate stability, and uniformity of aggrecan spacing; concentrations greater than 10% led to the formation of superaggregates (aggregates with sedimentation velocities greater than 100 S that may result from linking two or more hyaluronan filaments) but decreased aggregate stability; and concentrations of less than 4% link protein significantly decreased aggregation, the size and stability of aggregates, and the regularity of aggrecan spacing. The latter observations suggest that a decline in the concentration of link protein could decrease the organization and stability of the articular cartilage matrix. 相似文献
35.
A G Lawrence E T Houang E Hiscock M B Wells E Colli M Scatigna 《Current medical research and opinion》1990,12(2):114-120
An open, randomized comparative clinical trial was performed in 153 patients suffering from symptomatic vaginal candidiasis confirmed by mycological tests. Patients were allocated at random into two groups: the first group (consisting of 75 subjects) was treated with a single vaginal ovule of fenticonazole (600 mg) and the second group (consisting of 78 subjects) was treated with a single vaginal tablet of clotrimazole (500 mg). Therapeutic efficacy was assessed by microbiological and clinical criteria 7 days and 1 month (when possible) after the single dose treatment. At the first follow-up visit, complete disappearance of the signs and symptoms or a highly significant reduction of their intensity was observed in both treatment groups. No significant difference was evident between the two drugs. At 7 days, the mycological tests gave negative results in 92% of the patients in the fenticonazole group and in 88.5% of the patients in the clotrimazole group. The difference between the two treatment groups was again not statistically significant. The second follow-up visit was performed in 55 (73.3%) patients of the fenticonazole group and in 52 (66.7%) patients of the clotrimazole group. The results indicate that 83.6% of patients in the fenticonazole group and 69.2% of patients in the clotrimazole group were still disease free at the time of this visit. Both drugs were well tolerated. Mild, local and short lasting side-effects were reported in only 5 cases of the group treated with fenticonazole.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
36.
37.
Miguel J. Farolan M.D. Salve G. Ronan M.D. Lawrence M. Solomon M.D. Deborah S. Loeff M.D. 《Pediatric dermatology》1992,9(3):264-267
A 20-month-old Kuwaiti girl had manifestations of lipoid proteinosis, a rare autosomal recessive disorder seen more commonly in Caucasians. This condition is diagnosed based on clinical, histopathologic, and ultrastructural criteria. Its biochemical and genetic aspects are still poorly understood. 相似文献
38.
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40.
Alan B. Storrow MD Lawrence B. Stack MD Phred Petersen 《Academic emergency medicine》1994,1(5):454-462
In the emergency department, photography requires an expedient, portable, adaptable, and relatively simple camera system to take advantage of fleeting opportunities for recording visually educational material. These prerequisites are different from those for traditional medical photography, for which relatively plentiful time and advanced equipment are routinely available. Medical photography departments provide an invaluable service, but are rarely convenient for immediate or spontaneous emergency. department photographs. Although no single system or technique is optimal in all these areas, the authors find certain components and approaches work well. They review photographic equipment, paying attention to speed, ease of use, and quality of output. They also review simple techniques such as film choice, lighting, close-up photography, standardization, copy work, and radiographs. Attention to these details can help the inexperienced photographer obtain a system and begin to enjoy the rewards of effective photography in the emergency department. 相似文献