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991.
Cephalometric analysis of skeletodental features is accepted as an integral part of orthodontic diagnosis and treatment planning. This assumes that diagnostic cephalometric variables affect prognosis and thus help reduce malocclusion severity, which is the aim of orthodontic treatment. The aim of this study was to assess the predictive value of 41 commonly used cephalometric parameters with regard to pretreatment severity and treatment outcomes. Pretreatment severity was assessed by using the Peer Assessment Rating (PAR) occlusal index, an instrument that has been shown to be valid and reliable. Treatment outcomes consisted of (1) posttreatment malocclusion severity (post-PAR), (2) relative improvement (percent PAR reduction), and (3) treatment duration. Complete records, including cephalograms, of 223 treated Class II cases were analyzed by means of separate multiple linear regression models. Each of the outcome variables and the pretreatment severity served as the respective dependent variables, and the cephalometric parameters served as the independent or predictor variables. The cephalometric parameters explained 39.2% of the pretreatment severity variance, 17. 9% of posttreatment severity variance, 15.7% of relative treatment improvement variance, and 20.0% of treatment duration variance.  相似文献   
992.
A clinical recovery score (CRS) assessing recovery after general anesthesia was compared with the Digit-Symbol Substitution Test (DSST), Trieger Test (TT), a patient-completed visual analogue scale for alertness (VAS), and an independent observer's evaluation of recovery. The CRS included ratings of the following parameters: activity, respiration, circulation, consciousness, ambulation, color, and nausea and vomiting. Forty patients requiring the removal of three or four third molars participated in the study. All patients received the same general anesthetic technique. Each patient was evaluated by the five methods preoperatively, on admission to the recovery room, and at 15-min intervals until discharge. The four recovery tests (CRS, DSST, TT, VAS) were evaluated using chi 2 analysis to determine if there was any overall difference among the tests using the observer's determination of home readiness as the standard for discharge. The CRS was significantly more in agreement with the observer's determination than were the paper and pencil tests. The recovery tests were also evaluated with regard to instances of early dismissal or prolonged retention of the patient, again using the observer's determination as the "gold standard." The CRS was the only recovery test devoid of early dismissals. We conclude that the CRS provides a valid, simple measure of recovery that can be readily used in offices providing outpatient anesthesia and in studies measuring clinical recovery from anesthesia or sedation.  相似文献   
993.
G Dunnington  D Witzke  R Rubeck  A Beck  J Mohr  C Putnam 《Surgery》1987,102(2):291-296
A prospective study was designed to assess the teaching effectiveness of active learning in problem-oriented small group sessions (POSGS) compared with passive learning in didactic lectures (DL). Third-year medical students participated in a POSGS on breast disease and a standardized DL on thyroid disease (N = 23) or participated in a POSGS on thyroid disease and a DL on breast disease (N = 19). Students were tested with a multiple-choice examination (MCQ) and a highly structured oral examination (OE) administered by faculty members blinded about student group. Results of a between-within analysis of variance performed separately for breast and thyroid disease yielded significant group differences because of instructional method for thyroid disease (p = 0.003) and approached significance for breast disease (p = 0.095). Although no significant interactions were detected with percentage scores, a significant interaction between group membership and test type was noted for thyroid disease when the percentage scores were transformed to Z scores. We conclude that regardless of topic or testing method, students in POSGS tended to perform better than students in a DL and that the POSGS offers significant advantages over the DL in teaching surgery to third-year medical students.  相似文献   
994.
Besides assuring growth and development in early infancy, human breast milk plays a key role in preventing infections, in particular by favouring the growth of bifidobacteria. The development of infant formulas containing probiotic agents consequently represents a significant advance in the provision of an optimal alternative to breast feeding when this is not feasible. A further concern is to avoid an excessively high protein content relative to breast milk, potentially favouring obesity in later life. OBJECTIVES: The objective of this open Multicenter comparative study was to demonstrate that a new infant formula, characterized by a reduced protein content and the presence of a probiotic agent, was as effective as conventional formulas in assuring growth during the first months of life. POPULATION AND METHODS: The study population comprised full-term healthy infants with an age at inclusion of 1-28 days, whose mothers no longer wished to continue breast feeding or were unable to breast feed. The test formula (GE), enriched with Bifidobacterium lactis, had a protein content of 1.5 g/100 ml. The primary end point was daily weight gain from day 0 to day 90. Secondary end points were daily increase in height and cranial circumference, overall and gastrointestinal tolerance and formula acceptability. A total of 203 infants were included in the analysis, 117 receiving GE and 86 the formula habitually prescribed by the paediatrician. RESULTS: Daily gains in weight, height and cranial circumference did not differ significantly between the groups. The rates of overall and gastrointestinal adverse events were comparable in the two groups and the acceptability of GE was consistently good, similar to that of the standard formulas. CONCLUSION: The results of this study demonstrated that the new probiotic infant formula GE has equivalent efficacy to conventional formulas in achieving growth in early infancy, and is well tolerated.  相似文献   
995.
Bone strength, a key determinant of fracture risk, has been shown to display clear sexual dimorphism after puberty. We sought to determine whether sex differences in bone mass and hip bone geometry as an index of strength exist in school‐age prepubertal children and the degree to which the differences are independent of body size and lean mass. We studied 3514 children whose whole‐body and hip scans were measured using the same densitometer (GE‐Lunar iDXA) at a mean age of 6.2 years. Hip dual‐energy X‐ray absorptiometry (DXA) scans underwent hip structural analyses (HSA) with derivation of bone strength indices. Sex differences in these parameters were assessed by regression models adjusted for age, height, ethnicity, weight, and lean mass fraction (LMF). Whole‐body bone mineral density (BMD) and bone mineral content (BMC) levels were 1.3% and 4.3% higher in girls after adjustment by LMF. Independent of LMF, boys had 1.5% shorter femurs, 1.9% and 2.2% narrower shaft and femoral neck with 1.6% to 3.4% thicker cortices than girls. Consequent with this geometry configuration, girls observed 6.6% higher stresses in the medial femoral neck than boys. When considering LMF, the sexual differences on the derived bone strength indices were attenuated, suggesting that differences in muscle loads may reflect an innate disadvantage in bone strength in girls, as consequence of their lower muscular acquisition. In summary, we show that bone sexual dimorphism is already present at 6 years of age, with boys having stronger bones than girls, the relation of which is influenced by body composition and likely attributable to differential adaptation to mechanical loading. Our results support the view that early life interventions (ie, increased physical activity) targeted during the pre‐ and peripubertal stages may be of high importance, particularly in girls, because before puberty onset, muscle mass is strongly associated with bone density and geometry in children. © 2015 American Society for Bone and Mineral Research.  相似文献   
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998.
Abstract

Objectives

To examine body composition, including the relationship between body mass index (BMI) and total body fat, in women and men with complete motor paraplegia and to make comparisons with able-bodied controls.

Methods

In 13 subjects with traumatic, complete motor paraplegia (six women, seven men) and 39 sex-, age-, and BMI-matched controls from the community (18 women, 21 men), we measured total and regional (upper extremities, trunk, and lower extremities) lean and fat mass using total body dual-energy X-ray absorptiometry.

Results

Both women and men with paraplegia had significantly lower lean mass in their lower extremities, as would be expected, and in their total body when compared with controls. However, they had significantly greater lean mass in their upper extremities than controls (4.4 kg vs. 3.6 kg, P = 0.004 and 8.6 kg vs. 6.7 kg, P < 0.001 in women and men, respectively); all subjects with paraplegia studied used manual wheelchairs. Although total body fat mass was significantly greater in women (P = 0.010) and men (P = <0.001) with paraplegia compared with controls, for the equivalent total body fat mass, BMI was actually lower in women and men with paraplegia than controls (e.g. 20.2 kg/m2 vs. 25.0 kg/m2, respectively).

Conclusion

We report on body composition in persons with complete motor paraplegia, including women on whom limited information is currently available. Our results support the need to define better assessments of obesity in both women and men following spinal cord injury, particularly of central body fat distribution, as BMI underestimates adiposity in this population.  相似文献   
999.
Background The clinical staging of renal cortical tumors traditionally has not evaluated the potential effect of histological subtypes on survival. Evidence suggests that conventional clear cell renal cell carcinoma (RCC) and nonconventional clear cell RCC (chromophobe and papillary) have different metastatic potential. Using a large renal tumor database, we examined the effect of tumor histology on the pattern of metastasis and patient survival. Methods All patients with nonmetastatic renal cortical tumors undergoing partial or radical nephrectomy were identified from a renal tumor database between July 1989 and July 2002. Kaplan-Meier and Cox regression tests were used for statistical analysis. Results Analysis revealed 1057 patients: 794 with conventional clear cell RCC, 157 with papillary RCC, and 106 with chromophobe RCC. Metastasis occurred in 95 conventional clear cell RCC, 9 papillary RCC, and 6 chromophobe RCC. Metastasis occurred in 95 conventional clear cell RCC, 9 papillary RCC, and 6 chromophobe RCC with a median follow-up of 34.6, 43.0, and 33.2 months, respectively. Using log-rank analysis, chromophobe and papillary RCC were associated with an improved disease-free survival at 5 years (P=.009 and .015, respectively). Multivariate analysis revealed tumor size, stage, and chromophobe histology as significant variables for disease progression. Conclusions Renal cortical tumors have distinct histological subtypes with varying degrees of metastatic potential. Conventional clear cell RCC, which comprises two thirds of renal cortical tumors presenting with localized disease, has a less favorable outcome when compared with papillary and chromophobe RCC. Controlling for size and stage, chromophobe, and not papillary, RCC was a significant variable for disease progression compared with conventional clear cell RCC. Knowledge of renal cortical tumor histological subtype is critical for projecting prognosis, tailoring follow-up strategies, and designing clinical trials. Presented at the 56th Annual Cancer Symposium, Society of Surgical Oncology, San Diego, CA, March 5–9, 2003.  相似文献   
1000.
Expression of Wilms tumor gene (WT1) in epithelial ovarian cancer   总被引:4,自引:0,他引:4  
OBJECTIVES: The identification of proteins that are selectively expressed in cancer and with potential to elicit an immune response is the first step towards antigen-specific immunotherapy. The Wilms tumor gene product (WT1) is inherently immunogenic and is now thought to be oncogenic. The aim of this study was to determine the expression of WT1 in epithelial ovarian cancer (EOC) and correlate with clinico-pathologic characteristics. METHODS: WT1 expression was examined using immunohistochemistry applied on a tissue microarray of normal tissues and a panel of 100 EOC tissues. The distribution of WT1 expression and clinico-pathologic variables were analyzed. Survival probabilities were estimated by Kaplan-Meier method, and statistical significance was determined by the log-rank test. RESULTS: WT1 expression was observed in 78/100 of specimens. The predominant expression pattern was homogenous, occurring in 66/100 (66%) of WT1-positive specimens, while 12/100 (12%) demonstrated heterogeneous staining. In normal tissues, WT1 expression was noted in kidneys, splenic capsule, Sertoli cells of the testis, and granulosa cells of the ovary. The median follow-up of the patient population was 30 months. Patients with WT1-positive tumors tended to have a higher grade (P = 0.006) and stage (P = 0.002) of tumor. However, there were no significant differences in the distribution of patients with WT1-positive tumors in relation to disease-free and overall survival. CONCLUSIONS: Our data demonstrate that WT1 is expressed at high frequency in patients with EOC. Since WT1 demonstrates tissue-restricted expression and is inherently immunogenic, it could represent an attractive target for antigen-specific immunotherapy in EOC.  相似文献   
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