Gastroduodenal mucus is present as a water insoluble gel adherent to the mucosal surface and as a viscous mobile solution in the lumen. The protective properties of the mucus against acid (with bicarbonate), pepsin (diffusion barrier) and mechanical damage depend on the quality (structure) and quantity (thickness) of the adherent mucus gel layer. Adherent mucus is a viscoelastic gel which is 95% (v/v) water. It is permeable to ions and smaller molecules (Mr c. 1000), but is impermeable to large proteins (Mr,c. 17,000) including pepsins. However, mucus is solubilized rapidly by pepsin, more slowly (>-1 h) by thiol agents, and is unchanged following exposure to bile, acid and ethanol (<40%). Glycoprotein macromolecules (Mr≥2×106) are the structural components of the mucus gel and have a polymeric, structure of glycoprotein subunits (Mrc. 5×105, for gastric mucus) joined by disulphide bridges between their protein cores. This glycoprotein polymerization, which is essential for gel formation and hence function, is the site of action of proteolytic enzymes and thiol agents. The glycoprotein polymeric structure is deficient in antral mucus from patients with peptic ulcer disease.In vivo, adherent mucus forms a thin but continuous cover of variable thickness (50–450 μm in man, about two-fold less in rat) over the gastroduodenal mucosa. Pepsin in gastric juice will rapidly dissolve this mucus cover and can be active up to luminal pH values of 5. Mucus erosion by pepsin or by abrasion must be balanced by its secretion. Prostaglandins and carbachol stimulate a rapid increase (within minutes) in mucus thickness of up to two-fold. Soluble luminal mucus can be increased by mucus secretagogues, mucosal damaging agents, or peptic degradation of adherent mucus. Increases in luminal mucus can occur independently of increased gel thickness. 相似文献
The effect of conditioning stimuli on the F-response was investigated in normal subjects using stimulus pairs with interstimulus intervals of 1 to 400 ms. The "recovery curve" for the F-response was found to be similar to that for the H-reflex but differences were found between male and female subjects. The significance of these findings is discussed. 相似文献
A 6-year-old girl with a granulocytic sarcoma (GS) of the left maxillary sinus that followed a uniquely indolent clinical course (3.5 years) and was associated with highly destructive skeletal disease is described. The tumor cells demonstrated an unusual hematogenous "homing" preference for bone and soft tissue sites. Tumor cell characterization with immunologic markers, electron microscopy, cytochemistry, and cytogenetic studies revealed that the tumor cells expressed OKM1 and MMA (Leu-M1), but not HLA-DR, B-, or T-cell markers. The cells were nonspecific esterase- and myeloperoxidase-positive, had ultrastructural features of promyelocytes, and were clonal. The laboratory characterization of the tumor cells in this clinically unusual case of GS illustrates the utility of monoclonal antibodies, applied in conjunction with cytochemistry and ultrastructural analysis, in establishing the specific diagnosis, cell lineage, and maturational stage of this tumor. 相似文献
The purpose of this study was to evaluate the appropriateness of the predominantly clinical PharmD curriculum in light of actual employment patterns of PharmD graduates. Data were gathered via a survey of PharmD graduates from the seven post-baccalaureate programs active since 1972. Respondents were asked about their employment patterns and characteristics; about their formal education in the areas of management, statistics, and research methods; and to indicate whether they had completed residencies or fellowships. The results indicate that many PharmD graduates are employed in positions requiring considerable nonclinical skills, especially management skills. The results further indicate that few respondents have completed formal education, residencies, or fellowships which would prepare them for management or other nonclinical positions. Consequently, it appears that PharmD programs should require considerably more management training and education in order to adequately prepare their graduates for the positions open to them. 相似文献
The Family Check-Up 4 Health (FCU4Health) is an adaptation of the Family Check-Up (FCU) for delivery in primary care settings. While maintaining the original FCU’s focus on parenting and child behavioral health, we added content targeting health behaviors. This study evaluated whether the adapted FCU maintained positive effects on parenting (positive behavior support, limit setting, parental warmth) and child behavioral health (self-regulation, conduct problems, emotional problems). Pediatric (6–12 years) primary care patients with a BMI?≥?85th%ile (n?=?240) were recruited from primary care clinics in Phoenix. Children were 75% Latino, 49% female, and 73% Medicaid recipients. This type 2 effectiveness-implementation hybrid trial compared families randomized to FCU4Health (n?=?141) or usual care (n?=?99). FCU4Health was delivered over a period of 6 months. This study focuses on a priori secondary outcomes included parenting and child behavioral health targets of the original FCU, assessed at baseline and 3, 6, and 12 months. Significant improvements were found for the FCU4Health condition, compared to usual care, in parenting from baseline to the 3-month assessment [β?=?.17 (.01; .32)]. Parenting predicted improvements in child self-regulation at 6-months [β?=?.17 (.03; .30)], which in turn predicted reductions in conduct problems [β?=?? .38 (? .51; ? .23)] and emotional problems [β?=?? .24 (? .38; ? .09)] at 12 months. Ethnicity and language of delivery (English or Spanish) did not moderate these effects. The FCU4Health can improve parenting and child behavioral health outcomes when delivered in primary care.
We investigated the genetic profiles of killer cell immunoglobulin-like receptors (KIRs) in Ebola virus–infected patients. We studied the relationship between KIR–human leukocyte antigen (HLA) combinations and the clinical outcomes of patients with Ebola virus disease (EVD). We genotyped KIRs and HLA class I alleles using DNA from uninfected controls, EVD survivors, and persons who died of EVD. The activating 2DS4–003 and inhibitory 2DL5 genes were significantly more common among persons who died of EVD; 2DL2 was more common among survivors. We used logistic regression analysis and Bayesian modeling to identify 2DL2, 2DL5, 2DS4–003, HLA-B-Bw4-Thr, and HLA-B-Bw4-Ile as probably having a significant relationship with disease outcome. Our findings highlight the importance of innate immune response against Ebola virus and show the association between KIRs and the clinical outcome of EVD. 相似文献
A growing body of evidence has demonstrated the prognostic significance of sarcopenia in surgical patients as an independent predictor of postoperative complications and outcomes. These included an increased risk of total complications, major complications, re-admissions, infections, severe infections, 30 d mortality, longer hospital stay and increased hospitalization expenditures. A program to enhance recovery after surgery was meant to address these complications; however, compliance to the program since its introduction has been less than ideal. Over the last decade, the concept of prehabilitation, or “pre-surgery rehabilitation”, has been discussed. The presurgical period represents a window of opportunity to boost and optimize the health of an individual, providing a compensatory “buffer” for the imminent reduction in physiological reserve post-surgery. Initial results have been promising. We review the literature to critically review the utility of prehabilitation, not just in the clinical realm, but also in the scientific realm, with a resource management point-of-view. 相似文献
Quality of Life Research - The psychometric properties of the Perth A-loneness Scale (PALs) have been extensively validated using classical test theory, but to date no studies have applied a Rasch... 相似文献