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1.
BackgroundThe authors evaluated racial/ethnic differences and their socioeconomic determinants in the oral health status of U.S. children, as reported by parents.MethodsThe authors used interview data from the 2003 National Survey of Children's Health, a large representative survey of U.S. children. They calculated weighted, nationally representative prevalence estimates for non-Hispanic whites, non-Hispanic blacks and Hispanics, and they used logistic regression to explore the association between parents' reports of fair or poor oral health and various socioeconomic determinants of oral health.ResultsThe results showed significant racial/ethnic differences in parental reports of fair or poor oral health, with prevalences of 6.5 percent for non-Hispanic whites, 12.0 percent for non-Hispanic blacks and 23.4 percent for Hispanics. Although adjustments for family socioeconomic status (poverty level and education) partially explained these racial/ethnic disparities, Hispanics still were twice as likely as non-Hispanic whites to report their children's oral health as fair or poor, independent of socioeconomic status. The authors did find differences in preventive-care attitudes among groups. However, in multivariate models, such differences did not explain the disparities.ConclusionsSignificant racial/ethnic disparities exist in parental reports of their children's oral health, with Hispanics being the most disadvantaged group. Disparities appear to exist independent of preventive-care attitudes and socioeconomic status.  相似文献   
2.
牙列缺损的计算机三维建模   总被引:4,自引:5,他引:4  
目的 建立牙列缺损的计算机三维模型。方法 采用表面绘制法,依据CT扫描头颅骨标本获得的二维断层图像数据在3D Studio Max中沿牙体长轴放样、微调并赋以材质,得到牙列缺损的计算机三维模型。结果 能在计算机中方便快速地模拟任意类型的牙列缺损,并可全方位地旋转、放大和缩小。结论 提供了一种牙列缺损三维建模的新方法,有利于三维义齿专家系统的开发和计算机辅助教学。  相似文献   
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组织工程化人形下颌骨髁状突的实验研究   总被引:4,自引:0,他引:4  
目的 评价采用组织工程技术构建人下颌骨髁状突软骨复合组织的可行性。方法 以可降解生物材料聚羟基乙酸 (polyglycolicacid ,PGA) /聚乳酸 (polylacticacid ,PLA)预制人下颌骨髁状突模型 ,体外培养扩增牛骨膜成骨细胞和牛关节表面软骨。实验分 3组 :第 1组 ,模型内仅注入 1.5 %藻酸钙和 30 %氧化乙丙烯 ;第 2组 ,模型内分别注入成骨细胞和软骨细胞悬液 ,浓度为 5× 10 7/ml;第 3组 ,模型内接种成骨细胞藻酸钙悬液 ,同时在模型关节表面涂敷软骨细胞 PluronicF12 7悬液 ,浓度为 5× 10 7/ml。分别植入裸鼠皮下 ,12周后取材 ,作大体和组织学观察。结果 第 1组无骨和软骨形成 ,模型支架明显缩小 ,形态不规则 ;第 2组仅留残缺不全的组织结构 ,标本体积缩小变形 ;第 3组形态结构与原植入模型支架相同 ,组织学观察有骨和软骨组织结构 ,两者界面连接有序 ,骨组织内有大量新生骨板。结论 以人工合成生物材料预制人下颌骨髁状突支架 ,采用组织工程技术 ,可以在裸鼠体内构建具有骨软骨复合结构的正常形态的人形下颌骨髁状突 ,从而为进一步临床应用提供了理论依据  相似文献   
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6.

Background

Peripheral nerve blockade is used to provide analgesia for patients undergoing total knee arthroplasty. This study compared a single-injection adductor canal block (SACB) with adjuvants to continuous adductor canal blockade (CACB). The hypothesis was that the 2 groups would have equivalent analgesia at 30 hours after neural blockade.

Methods

This was a double-blinded, randomized, controlled, equivalency trial. Sixty patients were randomized to either the SACB group (20 mL of 0.25% bupivacaine, 1.67 mcg/mL of clonidine, 2 mg of dexamethasone, 150 mcg of buprenorphine, and 2.5 mcg/mL of epinephrine) or the CACB group (20 mL 0.25% of bupivacaine injection with 2.5 mcg/mL of epinephrine followed by an 8 mL/h infusion of 0.125% bupivacaine continued through postoperative day 2). The primary outcome was movement pain scores at 30 hours using the numeric rating scale (NRS). The secondary outcomes included serial postoperative NRS pain scores (rest and movement every 6 hours), opioid consumption, time to first opioid administration, ability to straight leg raise, patient satisfaction, length of stay, and the incidence of nausea/vomiting.

Results

An intention-to-treat analysis included 59 patients. The NRS pain scores with movement were equivalent at 30 hours (SACB 5.5 ± 2.8 vs CACB 5.7 ± 2.9 [mean NRS ± standard deviation]; mean difference 0.2 [?1.5 to 1.0 {90% confidence interval}]). All NRS pain scores were equivalent until 42 hours (rest) and 48 hours (rest and movement) with the CACB group having lower pain scores. Other secondary outcomes were not statistically different.

Conclusion

An SACB provides equivalent analgesia for up to 36 hours after block placement when compared with a CACB for patients undergoing total knee arthroplasty, though a CACB was favored at 42 hours and beyond.  相似文献   
7.
中西医结合治疗老年高脂血症   总被引:2,自引:1,他引:2  
目的:探讨中西医结合治疗高脂血症的临床疗效。方法:符合高脂血症标准的老年患者120例,随机分为A、B2组各60例,A组采用益肾化淤、利湿化浊为主的中药及西药辛伐他汀片治疗;B组则单纯用辛伐他汀片治疗。治疗前及治疗4周后2组均行全套血脂水平测定。结果:与B组比较,A组血清总胆固醇(TC)及甘油三酯(TG)均明显下降,HDL明显上升(均P〈0.05);A组临床控制率明显高于B组(P〈0.05);治疗后A组患者未见肝功能损害,B组转氨酶及转肽酶轻度异常,2例。停药3个月后,A组复发率低于B组(2.2%、8.8%,P〈0.05)。结论:中西医结合治疗老年高脂血症的临床效果明显优于单一的一种治疗方法,值得临床进一步推广应用。  相似文献   
8.
Responses to the synthetic terpolymer L-glutamic acid, L-lysine, L-tyrosine (GLT) in the mouse are controlled by H-2-1inked Ir-GLTgenes. (Responder × nonresponder) F(1) hybrid mice, themselves phenotypic responders, can be primed with GLT to develop specific helper cells capable of interacting with 2,4-dinitrophenyl hapten (DNP)-primed F(1) B cells in response to DNP-GLT. Unlike the indiscriminant ability of F(1) helper T cells for conventional antigens (i.e. not Ir gene-controlled), which can help B cells of either parental type (as well as F(1)) equally well, GLT-primed F(1) T cells can only provide help under normal circumstances for B lymphocytes of responder parent origin; they are unable to communicate effectively with nonresponder parental B cells (1, and the present studies). The present studies reveal, however, that the induction of a parental cell-induced allogeneic effect during priming of F(1) mice to GLT actually dictates the direction of cooperating preference that will be displayed by such F(1) helper cells for B cells of one parental type or the other. Thus, F(1) T cells, primed to GLT under the influence of an allogeneic effect induced by parental BALB/c cells, develop into effective helpers for nonresponder A/J B cells, but fail to develop effective helpers for responder BALB/c B cells, and vice-versa. In contrast, F(1) T cells, primed to GLT under the influence of an allogeneic effect induced by either parental type, display significantly enhanced levels of helper activity for B cells derived from F(1) donors. These results are interpreted to reflect the existence of two interdependent events provoked by the allogeneic effect: one event augments the differentiation of GLT-specific helper T cells belonging to the subset corresponding to the opposite parental type; this would explain the development of increased helper activity provided to partner B cells of opposite parental type (as well as of F(1) origin). The second event, we postulate, involves the production of responses against the receptors which normally self-recognize native cell interaction determinants; this form of anti-idiotype response is restricted against self- recognizing receptors of the same parental type used for induction of the allogeneic effect, hence explaining diminished helper activity of such F(1) cells for partner B lymphocytes of corresponding parental type.  相似文献   
9.

Objectives

The perceived threat of HIV transmission through spitting and biting is evidenced by the increasing use of “spit hoods” by Police Forces in the UK. In addition, a draft parliamentary bill has called for increased penalties for assaults on emergency workers, citing the risk of communicable disease transmission as one justification. We aimed to review literature relating to the risk of HIV transmission through biting or spitting.

Methods

A systematic literature search was conducted using Medline, Embase and Northern Lights databases and conference websites using search terms relating to HIV, AIDS, bite, spit and saliva. Inclusion and exclusion criteria were applied to identified citations. We classified plausibility of HIV transmission as low, medium, high or confirmed based on pre‐specified criteria.

Results

A total of 742 abstracts were reviewed, yielding 32 articles for full‐text review and 13 case reports/series after inclusion and exclusion criteria had been applied. There were no reported cases of HIV transmission related to spitting and nine cases identified following a bite, in which the majority occurred between family (six of nine), in fights involving serious wounds (three of nine), or to untrained first‐aiders placing fingers in the mouth of someone having a seizure (two of nine). Only four cases were classified as highly plausible or confirmed transmission. None related to emergency workers and none were in the UK.

Conclusions

There is no risk of transmitting HIV through spitting, and the risk through biting is negligible. Post‐exposure prophylaxis is not indicated after a bite in all but exceptional circumstances. Policies to protect emergency workers should be developed with this evidence in mind.  相似文献   
10.
Within the United Kingdom, the statutory supervision of midwives has a central role in both the provision of safe, high-quality maternity services and in the regulation of midwifery practice. Despite its long history, little is currently known about how midwives and their supervisors perceive and experience the statutory supervisory process.  相似文献   
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