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1.
The extracellular matrix of stratum corneum: role of lipids in normal and pathological function 总被引:4,自引:0,他引:4
The mammalian stratum corneum, formerly treated as a homogeneous film, is now more properly viewed as a two-compartment system. The cornified cell is protein-enriched and lipid-depleted, lying embedded in an expanded extracellular matrix of highly nonpolar lipids. Because of its strategic location between the cornified layer, this lipid matrix is responsible for many phenomena related to the permeability barrier, as well as cohesion and desquamation. Thus, manipulation of this compartment could lead to enhanced drug delivery and improved lubrication, as well. 相似文献
2.
Potentially dangerous antibiotic resistant contaminants have permanently penetrated at least well-off western populations. The danger is so evident that some hospitals have started to refuse accepting patients who carry such bacteria. Sampling and enrichment measures in hygiene monitoring must be updated as they are corner stones in handling the problems and safeguarding the health care units. Their patients, when exposed to microorganisms are strenuous to treat. Sometimes even this fails, if the infections are spreading in weakened patients. The present review summarizes currently used technologies and the abilities of bacteria to avoid detection. Improved protocols on environmental monitoring in healthcare units are required. They should be comparable with contamination control in industries. Actually these measures in health care should be even stricter because human lives are directly endangered as the resistance of especially elderly patients is low. 相似文献
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目的由于卒中风险随着狭窄严重程度的增加而升高,因此认为颈内动脉(ICA)接近闭塞患者的卒中风险很高。在现有的随机试验中,还没有专门针对这种情况进行探讨,因此其处理尚存在争汶。方法:对相关文献进行系统评价。结果:对ICA接近闭塞患者的处理还存在争议:一些学者支持进行干预,而另一些学者则认为存在风险或没有益处而反对进行干预。在ICA接近闭塞的有症状患者中进行一项比较外科治疗与最佳内科治疗的多中心前瞻性随机试验似乎非常困难,因为这类研究需要大量的患者。尽管如此,基于目前的证据,似乎很难拒绝手术治疗。结论:由于目前对ICA接近闭塞患者的最佳处理方案仍存在着争议,因此需要前瞻性观察性研究以证实其在有症状和无症状人群中的患病率以及相关的卒中风险。基于目前的证据,大多数医疗中心选择手术治疗,但它相对干内科治疗的特粱尚右待证章. 相似文献
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Hans-Georg Elias Daniel C. Chung Nobuo Donkai Goetz P. Hellmann Karel Solc Katsutoshi Nagai 《Macromolecular chemistry and physics.》1987,188(3):537-560
1-O-3-(4-Vinylphenyl)propyl-β-D -glucopyranose ( 1 ) undergoes in water a closed association under formation of N-mers. The unimer/N-mer association is directly visible in the Schlieren pattern of ultracentrifugal synthetic boundary experiments. Association numbers and mass-concentration-based equilibrium constants of association were calculated from the variation of N-mer concentrations with unimer concentrations and from the concentration dependence of inverse apparent average molar masses as measured by both vapor phase osmometry and sedimentation equilibrium. Association numbers were also calculated from the combination of sedimentation coefficients with diffusion coefficients, sedimentation coefficients with intrinsic viscosities, and diffusion coefficients with interinsic viscosities as well as from the dependence of apparent mass-average molar masses on inverse apparent number-average molar masses. All methods gave in general different association numbers and equilibrium constants. The effect, which was not found for other non-ionic amphiphiles, is probably due to the existence of consecutive equilibria between the unimer and a low molar mass P-mer which associates to a higher molar mass R-mer. Viscosity data are in agreement with the picture of a spherical micelle for the dominant P-mers with about 10 water molecules per glucose residue. The micellization of 1 is both enthalpy- and entropy-driven, in contrast to the micellization of 1-O-octyl-β-D -glucopyranose which is a strictly entropy-driven process. 相似文献
8.
Stratum corneum architecture, metabolic activity and interactivity with subjacent cell layers 总被引:3,自引:0,他引:3
Peter M. Elias 《Experimental dermatology》1996,5(4):191-201
9.
ABSTRACT: This study examined the decrease in cesarean section rates in relation to perinatal mortality between 1987 and 1993 at the primary referral hospital in north Jordan. Most of the population is at high risk and of low socioeconomic status. The cesarean section rate decreased from 15.5 percent in 1987 to 8.7 percent in 1993, and has remained at this low rate. During the same period the perinatal mortality dropped from 52 to 20.9 deaths per 1000 live births. These results do not include perinatal morbidity. The successful reduction of the cesarean section rate is attributed to active management of labor, trial of labor for women with a previous cesarean birth, and vaginal breech delivery in selected women. We conclude that the rate of cesarean delivery can be safely reduced in a developing country without adverse effects on birth outcomes. 相似文献
10.
D Elias 《Journal de chirurgie》1992,129(11):479-483
The cytoreductive surgery (CS) or surgical debulking of tumors is supported by the following experimental concept: the maximal but incomplete resection of huge tumoral masses (debulking) induces the passage of remaining cancerous cells in proliferative cycle. So, these remaining cells become sensitive to chemotherapy, or eventually to radiotherapy. In this way, the CS appears to be a neoadjuvant treatment to the chemotherapy, this last treatment being the powerful therapeutic. In this study, we have studied successively: the theoretical basis of the CS, the experimental positive and negative arguments of this concept, and then the positive and negative clinical applications. At least, it seems that CS is more a myth than a reality, and that we should only keep the classical concepts of curative surgery or palliative surgery. 相似文献