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101.
Induction of antibody to asialo GM1 by spermatozoa and its occurrence in the sera of homosexual men with the acquired immune deficiency syndrome (AIDS). 总被引:1,自引:2,他引:1 下载免费PDF全文
S S Witkin J Sonnabend J M Richards D T Purtilo 《Clinical and experimental immunology》1983,54(2):346-350
Compared to healthy homosexual and heterosexual men, homosexual men with acquired immune deficiency syndrome (AIDS) possessed significantly higher levels of IgG antibody to the neutral glycolipid asialo GM1 (ganglio-N-tetraosylceramide) (P less than 0.01). Of 31 homosexuals with AIDS, 36% possessed levels of this antibody that were at least two standard deviations above the mean of the healthy men. Furthermore, asialo GM1 antibody could be removed from serum by adsorption with spermatozoa. Weekly rectal insemination of male rabbits with rabbit semen also led to the appearance of antibody to asialo GM1 by 15 weeks. These results suggest that asialo GM1 is a component of ejaculated spermatozoa and demonstrate that rectal insemination by itself can lead to the production of antibodies to this glycolipid in the rabbit. In addition, asialo GM1 antibodies may be of value as a serological marker for the early detection of individuals with AIDS. 相似文献
102.
Implanted biomaterials are coated immediately with host plasma constituents, including extracellular matrix (ECM); this reaction may be undesirable in some cases. Poly(L-lysine)-grafted-poly(ethylene glycol) (PLL-g-PEG) has been shown to spontaneously adsorb from aqueous solution onto metal oxide surfaces, effectively reducing the degree of non-specific adsorption of blood and ECM proteins, and decreasing the adhesion of fibroblastic and osteoblastic cells to the coated surfaces. Cell adhesion through specific peptide-integrin receptors could be restored on surfaces coated with PLL-g-PEG functionalized with peptides of the RGD (Arg-Asp-Gly) type. To date, no study has examined the effect of surface modifications by PLL-g-PEG-based polymers on bacterial adhesion. The ability of Staphylococcus aureus to adhere to the ECM and plasma proteins deposited on biomaterials is a significant factor in the pathogenesis of medical-device-related infections. This study describes methods for visualizing and quantifying the adhesion of S. aureus to smooth and rough (chemically etched) titanium surfaces without and with monomolecular coatings of PLL-g-PEG, PLL-g-PEG/PEG-RGD and PLL-g-PEG/PEG-RDG. The different surfaces were exposed to S. aureus cultures for 1-24h and bacteria surface density was evaluated using scanning electron microscopy and fluorescence microscopy. Coating titanium surfaces with any of the three types of copolymers significantly decreased the adhesion of S. aureus to the surfaces by 89-93% for PLL-g-PEG, and 69% for PLL-g-PEG/PEG-RGD. Therefore, surfaces coated with PLL-g-PEG/PEG-RGD have the ability to attach cells such as fibroblasts and osteoblasts while showing reduced S. aureus adhesion, resulting in a selective biointeraction pattern that may be useful for applications in the area of osteosynthesis, orthopaedic and dental implantology. 相似文献
103.
The application of reversed-phase gradient high-performance liquid chromatography with UV detection to the determination of cortisol and cortisone in 24-h urine samples is described. The method employs Sep-pak C18 cartridges for the part-purification and concentration of the corticosteroids, with sample enrichment at the head of an HPLC pre-column and separation using water/acetonitrile gradient. The internal standard is 6alpha-methylprednisolone. Measurement of both cortisone and cortisol provides further information on adrenocortical function. 24-hour excretion rate data from normal subjects are reported. 相似文献
104.
The effect of buprenorphine on bremazocine-induced diuresis was tested in the rat to determine the nature of buprenorphine's action at the opioid receptor. Both morphine-tolerant and naive rats were used to account for possible antidiuretic effects of buprenorphine at the µ site. Separate experiments established that the morphine pretreatment caused profound tolerance with respect to the antidiuretic action of µ agonists. Buprenorphine acted as a potent antagonist (ID50 = 11µg/kg) of the diuretic action of the agonist bremazocine (ED50 = l0 µg/kg). The similar potency of buprenorphine as an antagonist of bremazocine in naive and morphine-tolerant rats further supports the hypothesis that buprenorphine exerts it's antidiuresis via an antagonistic effect at sites, rather than as an agonist at the µ sites. The high affinity displayed by buprenorphine at the opioid receptor in vivo is consistent with this conclusion. Hence, buprenorphine can now be classified as a partial agonist at the µ site and as an antagonist at the site against bremazocine induced urine flow, while its action at the site to which it has much lower affinity in vivo remains unknown. 相似文献
105.
Analysis of shortlisting of applicants for interview at St Mary's Hospital Medical School showed that factor analysis could reduce the selection criteria to three independent scales--"academic ability," "interests," and "community service"--all of which contributed to the interview decision. Early applicants scored more highly on all three factors but were still at a greater advantage in selection for interview than would have been predicted. The dean's judgment of priority for interview from the UCCA form was found to predict a candidate's chance of acceptance at other medical schools besides St Mary's. Analysis of interviewing showed high correlations among interviewers in their assessments, although there was evidence of influence by the chairmen. Factor analysis showed three major factors--academic suitability, non-academic suitability, and health--of which non academic suitability was the major determinant of interview success. Non academic suitability was related to personality (high extraversion and low psychoticism) and to the choices made on the UCCA form. The system of admission interviews enabled greater emphasis to be put on broader interests and achievements than if selection had been on the basis of UCCA application form alone. 相似文献
106.
D R White H B Muss R Michielutte M R Cooper D V Jackson F Richards J J Stuart C L Spurr 《American journal of clinical oncology》1984,7(2):183-190
Documentation of informed consent by patients entering clinical trials is an ethical and legal necessity. Federal regulations and judicial opinions have led to increasingly lengthy, detailed "consent" forms, yet published studies demonstrate that patients remain confused about the nature and anticipated consequences of study entry. It has been suggested that more detail may even alarm or further confuse patients. Seventy-five women undergoing chemotherapy for advanced breast cancer participated in this study which assessed patient preference for long-, medium-, or short-form length, and whether form length preference correlated with patient characteristics or indicators of patient autonomy in decision-making or physician dependency. Patient preferences for information were not predicted by the patient autonomy or physician dependency scores or by age, marital status, or level of education. The majority of patients expressed a preference for more detailed information about their treatment, yet a majority of patients given detailed forms answered questions basic to the study design incorrectly, irrespective of educational level. The increased detail included in the long forms was not reported to increase stress compared to the short forms. Patient information forms are a principal tool for informing patients for consent but if they are to perform their desired function they must be designed more carefully and evaluated more thoroughly than in the past. 相似文献
107.
108.
Amy E. Lawrence Justin T. Huntington Kate Savoie Michael Dykes Jennifer H. Aldrink Holden Richards Gail E. Besner Brian Kenney Jeremy Fisher Peter C. Minneci Marc P. Michalsky 《Journal of pediatric surgery》2021,56(1):55-60
PurposeThe objective of this quality improvement (QI) initiative was to implement a standardized clinical treatment protocol for patients presenting with primary spontaneous pneumothorax (PSP) in order to decrease hospital length of stay (LOS), diagnostic radiation exposure, and related cost.MethodsBaseline data from patients admitted with PSP from January 1, 2016 to July 31, 2018 were compared to data from patients managed using a newly developed evidence-based treatment pathway from August 1, 2018 to December 31, 2019. Standard QI methodology was used to track results.ResultsFifty-six episodes of PSP were observed during the baseline period and 40 episodes of PSP following initiation of the PSP protocol. The average LOS decreased from 4.5 days to 2.9 days. Patients underwent an average of 8.8 X-rays per admission preintervention versus 5.9 postintervention. The rate of CT scans decreased from 45% to 15% (p = 0.002). There was no significant difference in the rates of 30-day recurrence between the preintervention (13%) and postintervention (10%) groups (p = 0.7). Average admission costs per patient decreased by $1322 after adoption of the pathway.ConclusionsAdoption of a standardized treatment protocol for PSP led to a reduction in LOS, diagnostic imaging utilization, and cost without increasing clinical recurrence.Type of studyQuality improvement.Level of evidenceLevel III. 相似文献
109.
Liza Johannesson Anji Wall Andreas Tzakis Cristiano Quintini Elliott G. Richards Kathleen O’Neill Paige M. Porrett Giuliano Testa 《American journal of transplantation》2021,21(5):1699-1704
The parallel emergence of uterus transplantation (UTx) and other transplantation innovations including face and hand transplantation led to the categorization of the uterus as a vascular composite allograft (VCA). With >60 transplants and >20 births worldwide, UTx is transitioning rapidly from a research endeavor to an effective treatment option for women with uterine factor infertility. While it originally made sense to group the innovations under one umbrella, it is time to revisit the designation of UTx as a VCA. We describe how UTx needs unique policy, procedural codes, insurance contracts, and educational initiatives. We contend that separating UTx from VCAs may become necessary in the future to avoid hindering the growth and regulation of this field. 相似文献
110.
Hendriks Olivia Wei Yimeng Warrier Varun Richards Gareth 《Archives of sexual behavior》2022,51(4):2077-2089
Archives of Sexual Behavior - Previous research indicates a link between autism and transgender and gender-diverse identities, though the association is not yet fully understood. The current study... 相似文献