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71.
72.
This paper examines medical malpractice law as it applies to medically necessary oral health care. The basic legal concepts and reported cases involving medically necessary oral health care are reviewed. It is concluded that dental professionals and consumer advocates must advance their educational and legislative advocacy efforts so that health professional colleagues and the public will become aware of the importance of these services and insurers will routinely include coverage of medically necessary oral health care in their medical and dental policies. While failure to provide medically necessary oral health care can be violative of patient rights and legally actionable, medical malpractice litigation should always be the behavior modifier of last resort.  相似文献   
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We report on the development of a rapid nested PCR protocol for the detection of Pneumocystis carinii DNA in bronchoalveolar lavage (BAL) specimens in which the protocol included the use of a commercially available DNA extraction kit (GeneReleaser). GeneReleaser enabled us to obtain amplification-ready DNA within 20 min without requiring the purification of the DNA. The nested PCR was performed with the primers pAZ102-E, pAZ102-H, and pAZ102-L2 (A. E. Wakefield, F. J. Pixley, S. Banerji, K. Sinclair, R. F. Miller, E. R. Moxon, and J. M. Hopkin, Lancet 336:451-453, 1990.). Results were obtained in about 4 h with the adoption of denaturation, annealing, and extension steps shortened to 20 seconds. The sensitivity of the nested PCR was tested with a P. carinii cyst suspension and was found to be less than one cyst (one to eight nuclei). The detection limit was the same with the use of GeneReleaser or proteinase K-phenol chloroform for DNA extraction. The nested PCR assay was prospectively compared with staining with Giemsa and methenamine silver stains for the detection of P. carinii in 127 BAL samples from 105 human immunodeficiency virus-infected patients investigated for acute respiratory illness. Twenty-five BAL specimens (20%) were positive by staining and the nested PCR and 25 (20%) were negative by staining and positive by the nested PCR. These 25 BAL specimens with conflicting results were obtained from 23 patients, 82% of whom were receiving prophylactic therapy against P. carinii pneumonia (PCP). Only two patients were diagnosed with possible PCP. The final diagnosis was not PCP for 20 patients who were considered to be colonized or to have a low level of infection. This colonization is not of clinical importance but is of epidemiological importance. Our rapid, simple, and sensitive amplification protocol may be performed in clinical laboratories for the routine diagnosis of PCP with BAL specimens.  相似文献   
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76.
Objective To study the distribution and quantity of CD44VCD24- cells in breast cancer tissue and the cell lines,and as well as its correlation with the expression of various breast cancer markers and molecular subtyping of breast carcinoma.Methods The expression of CD44 / CD24,estrogen receptor,progesterone receptor,HER2,human estrogen-induced protein PS2,bcl-2 and nm23 in 60 cases of invasive ductal carcinoma of breast were studied by either single or double immunohistochemical staining.The co-expression of CD44 and CD24 in 3 breast cancer cell lines (MCF-7,MDA-MB-468,and MDA-MB- 231) was also examined.Results The quantity and distribution of CD44 + /CD24- cells varied greatly and no specific patterns were identified.The percentage of CD44 + /CD24- in breast cancer was 65%.The amount of CD44+/CD24- cells did not correlate with the age of patients,lymph node metastasis,tumor  size,molecular subtypes and expression of various breast cancer markers in breast carcinoma.The proportion of CD44+/CD24- cells in MCF-7,MDA-MB-468,and MDA-MB-231 cell lines was < 1%,5% and > 80% ,respectively.Conclusions CD44+ /CD24- cells are demonstrated in certain breast cancer tissues and cell lines.However,there is no relationship obtained between the quantity or the distribution of these cells and the molecular subtyping or the clinicopathologic parameters in breast cancer.  相似文献   
77.
目的:介绍抗人DR5单抗YM366EC-阿霉素结合物的制备及其细胞毒作用,以探讨YM366EC作为内源性导向载体的可能性。方法:采用氧化葡聚糖(Dex)T-40作为中介载体,联结抗人DR5YM366EC与阿霉素(ADR)制备交联物366EC-Dex-ADR,交联物中ADR与366EC的克分子比为71:1。经ELISA测定交联物的抗体活性大部分保持。MTT法体外测定其细胞毒性。结果:交联物对表达DR5受体的肿瘤细胞处理24小时的IC50是游离ADM的5倍,并且和肿瘤细胞DR5受体表达相关。结论:YM366EC具有良好的导向作用,结合物对肿瘤细胞有选择性杀伤作用。  相似文献   
78.
A new case of cutaneous Leishmaniasis to L. braziliensis Vianna, 1911, contracted in French Guyana is reported. The parasite, isolated in culture, is identified by enzymatic typing (13 zymoden). The identified zymodem is zymodem MON-43. It is the same of the WHO reference strain L. braziliensis s. st.  相似文献   
79.
A wireless power transfer system for endoscopic micro-robot operating at 36 kHz is presented in this paper. The issue of patient' s health and safety regarding exposure to the electromagnetic field is addressed. The specific absorption rate and current density can be used to investigate the electromagnetic influences on the biological tissues surrounded by the wireless power launching coil. In view of this purpose, the limited close-ound solenoid electromagnetic model is built, the relationship between the electric intensity and the specific absorption rate and current density is deduced, and the simulation experiments are done. Experimental results show that the values of SAR and current density related to different tissue catalogs are all very small and do not exceed their own limits respectively when the resonance frequency of operation is 36 kHz.  相似文献   
80.
目的 探索 pp60c-src( + ) 在神经生长端的表达特征及其生理意义。方法 用免疫细胞化学方法检测 pp60c-src( + ) 在初代培养鸡胚脊神经节细胞内的分布特征。结果 pp60c -src( + ) 的免疫活性分布在神经细胞的细胞膜下、核周体、神经突起 ;在生长端体部和丝状伪足 ,pp60c -src( + ) 的免疫活性较强 ,少数免疫活性较弱。在伸长的突起上有时可见 pp60c-src( + ) 免疫活性分布在串珠样膨体上。结论 pp60c-src( + ) 参与生长端的运动和生长 ;在生长端分化、神经生长过程中 ,pp60c-src( + ) 的调控作用具有时空特异性  相似文献   
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