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排序方式: 共有7968条查询结果,搜索用时 15 毫秒
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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5.
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
6.
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
7.
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
8.
Dominant A1: angiographic and clinical correlations with anterior communicating artery aneurysms. 总被引:1,自引:0,他引:1
It has been observed but never proven that anomalies of the anterior communicating artery complex are associated with anterior communicating artery aneurysms (ACAA). Therefore, in an effort to understand the significance of haemodynamic factors in the genesis, as well as the clinical course of ACAA, we evaluated the correlation between certain angiographic patterns of flow in the anterior circulation and the clinical findings of 51 patients with ACAA compared with 50 matched controls. Four significant associations which have never been validated were identified: 1) a dominant A1 (filling both A2's) was found in 57% of ACAA patients versus 14% of controls (p less than 0.001). 2) Unilateral hypoplasia of the opposite A1 was present in 24% of ACAA patients versus 6% of controls (p = 0.01). 3) Exclusive filling of the ACAA from one A1 occurred in 78%. 4) No statistically significant relationship was found between the anatomic flow patterns studied and the patients clinical presentation including age, sex, or grade. We conclude that anterior communicating artery aneurysms are significantly related in a majority of patients with the presence of a dominant A1, probably as the result of enhanced haemodynamic stress caused by this anatomic abnormality in the circulation. However, this association is not constant, and a dominant pattern of flow did not correlate with the clinical course. This is probably a reflection of the differences between factors initiating aneurysm formation and those influencing its growth, as well as of the relative limitations of angiography when pathophysiological extrapolations are attempted. 相似文献
9.
Brain tissue oxygenation in patients with cerebral occlusive disease and arteriovenous malformations
Hoffman W. E.; Charbel F. T.; Edelman G.; Ausman J. I. 《British journal of anaesthesia》1997,78(2):169-171
It is not clear if ventilation with oxygen increases brain tissue oxygen
pressure (PO2) during ischaemia. We have measured brain tissue PO2, carbon
dioxide pressure (PCO2) and pH during baseline anaesthesia and oxygen
ventilation in non-ischaemic control patients (n = 9), patients with
cerebral occlusive disease (n = 11) and patients with arteriovenous
malformations (AVM, n = 12). The same anaesthetic treatment was given to
all groups and anaesthesia was constant during the study. Arterial
pressure, brain temperature and arterial blood-gas tensions were similar
between groups. Under baseline conditions, brain tissue PO2 was mean 4.2
(SD 1.4) kPa in the controls and was 70% lower in patients with ischaemia
and AVM. Patients with occlusive disease also had elevated tissue PCO2 and
acidosis. During oxygen ventilation, PO2 increased to 7.5 (2.9) kPa in
controls and this was 50% greater than the increase in the ischaemia and
AVM patients. The results showed that baseline tissue oxygenation and
increases in PO2 during hyperoxia were attenuated in patients with
ischaemia or AVM.
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