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排序方式: 共有375条查询结果,搜索用时 125 毫秒
1.
C C Linnemann C Cannon M DeRonde B Lanphear 《Infection control and hospital epidemiology》1991,12(4):214-219
OBJECTIVE: To evaluate the effect of infection control programs on reported needlestick injuries in a general hospital. DESIGN: Surveillance of all reported needlestick injuries at the University of Cincinnati Hospital was maintained by the infection control department for five years, from 1985 through 1989. Data on individual workers were collected, tabulated on a monthly basis, and reviewed continually to monitor trends in injuries. During this time, the effects of each of three new infection control programs on reported injuries were evaluated sequentially. SETTING: A 700-bed general hospital that serves as the main teaching hospital of the University of Cincinnati. PARTICIPANTS: All employees of University Hospital who reported to personnel health for management of needlestick injuries. INTERVENTIONS: In 1986, an educational program to prevent injuries was initiated and continued throughout the surveillance period. In 1987, rigid sharps disposal containers were placed in all hospital rooms. In 1988, universal precautions were introduced with an intensive inservice. RESULTS: Surveillance identified 1,602 needlestick injuries (320/year) or 104/1,000/year. After the educational program began, reported injuries increased rather than decreased, and this was attributed to increased reporting. Subsequently, after installation of the new disposal containers, reported injuries returned to the levels seen prior to the educational program, but recapping injuries showed a significant decrease from 63/year to 30, or 20/1,000/year to 10. This decrease was observed in nurses but not in other healthcare workers. After universal precautions were instituted, total injuries increased slightly, but recapping injuries remained at 50% of the levels reported prior to the use of rigid sharps disposal containers. CONCLUSIONS: The three infection control programs failed to produce a major reduction in reported needlestick injuries, except for a decrease in recapping injuries associated with the placement of rigid sharps disposal containers in all patient rooms. These observations indicate that new approaches are needed to reduce needlestick injuries. 相似文献
2.
Different modulation by histamine of IL-4 and interferon-gamma (IFN-γ) release according to the phenotype of human Th0, Th1 and Th2 clones
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Histamine, an important inflammatory mediator in allergic diseases and asthma, has been reported to have modulator effects on T cells, suggesting that the bronchial microenvironment may regulate the function of resident T cells. We examined the effect of histamine on the release of the Th2-associated cytokines IL-4 and IL-5 and the Th1-associated cytokine IFN-γ by 30 CD4+ T cell clones from peripheral blood or bronchial biopsy of one atopic subject. Based on the IL-4/IFN-γ ratio, the clones were ascribed to the Th2 (ratio >1), Th0 (ratio 0.1 and 1) or Th1 (ratio <0.1) phenotype. Histamine inhibited IFN-γ production by Th1-like cells (P<0.02, Kruskall–Wallis), especially from bronchial biopsy, but had no effect on IL-4 release. Regarding Th0 clones, histamine inhibited IL-4 production (P<0.02) in a dose-dependent manner and slightly inhibited IFN-γ production, but had no effect on Th2-like cells. Histamine had a heterogeneous and insignificant effect on IL-5 production. The H2-receptor antagonist ranitidine completely reversed the inhibition of IL-4 and IFN-γ production, whereas the agonist dimaprit mimicked this effect. In contrast, H1- and H3-receptor agonists and antagonists had no significant effect. These data demonstrate that histamine has different effects on IL-4 and IFN-γ release by T helper cells according to their phenotype via H2-receptors. This study extends the immunomodulatory effects of histamine which may contribute to the perpetuation of airway inflammation in asthma. 相似文献
3.
Wiley S Swayne S Rubinstein JH Lanphear NE Stevens CA 《American journal of medical genetics. Part A》2003,(2):101-110
Children and adults with Rubinstein-Taybi Syndrome have specific medical conditions that occur with greater frequency than the general population. Based on the available information from the literature and clinical experience, recommendations for specific surveillance and interventions are made to guide those clinicians caring for individuals with Rubinstein-Taybi Syndrome. This is a first attempt at medical guidelines for individuals with RTS in the United States. On-going research is needed in many areas to guide decisions in medical care and allow for refinement of these medical guidelines. 相似文献
4.
The role of size, sequence and haplotype in the stability of FRAXA and FRAXE alleles during transmission 总被引:2,自引:5,他引:2
Murray A; Macpherson JN; Pound MC; Sharrock A; Youings SA; Dennis NR; McKechnie N; Linehan P; Morton NE; Jacobs PA 《Human molecular genetics》1997,6(2):173-184
Factors involved in the stability of trinucleotide repeats during
transmission were studied in 139 families in which a full mutation,
premutation or intermediate allele at either FRAXA or FRAXE was
segregating. The transmission of alleles at FRAXA, FRAXE and four
microsatellite loci were recorded for all individuals. Instability within
the minimal and common ranges (0-40 repeats for FRAXA, 0-30 repeats for
FRAXE) was extremely rare; only one example was observed, an increased in
size at FRAXA from 29 to 39 repeats. Four FRAXA and three FRAXE alleles in
the intermediate range (41-60) repeats for FRAXA, 31-60 for FRAXE) were
unstably transmitted. Instability was more frequent for FRAXA intermediate
alleles that had a tract of pure CGG greater than 37 although instability
only occurred in two of 13 such transmissions: the changes observed were
limited to only one or two repeats. Premutation FRAXA alleles over 100
repeats expanded to a full mutation during female transmission in 100% of
cases, in agreement with other published series. There was no clear
correlation between haplotype and probability of expansion of FRAXA
premutations. Instability at FRAXA or FRAXE was more often observed in
conjunction with a second instability at an independent locus suggesting
genomic instability as a possible mechanism by which at least some FRAXA
and FRAXE mutations arise.
相似文献
5.
JM Langley JC LeBlanc EE Wang BJ Law NE MacDonald I Mitchell D Stephens J McDonald FD Boucher S Dobson 《Pediatrics》1997,100(6):943-946
OBJECTIVE: To determine nosocomial transmission of respiratory syncytial virus (RSV) in Canadian pediatric hospitals, outcomes associated with nosocomial disease, and infection control practices. DESIGN: A prospective cohort study in the 1992 to 1994 winter respiratory seasons. SETTING: Nine Canadian pediatric university-affiliated hospitals. PARTICIPANTS: Hospitalized children with symptoms of lower respiratory tract infection (at least one of cough, wheezing, dyspnea, tachypnea, and apnea) and RSV antigen identified in a nasopharyngeal aspirate. RESULTS: Of 1516 children, 91 (6%) had nosocomial RSV (NRSV), defined as symptoms of lower respiratory tract infection and RSV antigen beginning >72 hours after admission. The nosocomial ratio (NRSV/[com-munity-acquired RSV {CARSV})] + NRSV) varied by site from 2.8% to 13%. The median length of stay attributable to RSV for community-acquired illness was 5 days, but 10 days for nosocomial illness. Four children with NRSV (4. 4%) died within 2 weeks of infection, compared with 6 (0.42%) with CARSV (relative risk = 10.4, 95% confidence interval: 3.0, 36.4). All sites isolated RSV-positive patients in single rooms or cohorted them. In a multivariate model, no particular isolation policy was associated with decreased nosocomial ratio, but gowning to enter the room was associated with increased risk of RSV transmission (incidence rate ratio 2.81; confidence interval: 1.65, 4.77). CONCLUSIONS: RSV transmission risk in Canadian pediatric hospitals is generally low. Although use of barrier methods varies, all sites cohort or isolate RSV-positive patients in single rooms. Children with risk factors for severe disease who acquire infection nosocomially have prolonged stays and excess mortality. 相似文献
6.
7.
HABIB BOUKERCHE MARIE-HéLèNE RUCHAUD-SPARAGANO CHRISTINE R OUEN JEAN BROCH IER CéCILE KAPLAN & JOHN LOUIS MCGREGOR 《British journal of haematology》1996,92(2):442-451
P-selectin (also called CD62, GMP-140, PADGEM, CD62P) is a recently described member of a family of vascular adhesion receptors expressed by activated platelets and endothelial cells that are involved in leucocyte cell adhesion. The aim of this study was to characterize a new monoclonal antibody (LYP7) directed against activated human blood platelets that inhibits ristocetin-induced platelet aggregation. Immunoadsorbent affinity chromatography and immunoprecipitation studies showed that LYP7 (IgG1) bound a surface-labelled glycoprotein (GP) which changed its apparent molecular mass (Mr) on reduction from 138 kD (situated below GPIIb) to 148 kD (above GPIIbα). LYP7 and S12, a monoclonal antibody directed against P-selectin immunoprecipitated the same band. Using ELISA assay, purified P-selectin was shown to bind LYP7 and S12 monoclonal antibodies. Binding sites of 125I-labelled LYP7, which was greatly increased on thrombin-stimulated (2 U/ml) washed platelets (10825±2886, mean ±SD) (Kd=1.5±0.5 nm ) compared to resting platelets (2801±1278, mean ±SD) (Kd=1.5±0.6 nm ), was found to be normal on thrombin-stimulated platelets taken from a patient with grey platelet syndrome or a patient with Glanzmann thrombasthenia. LYP7 (IgG1, F(ab′)2 or Fab fragments) inhibited ristocetin-induced platelet aggregation of platelets in a dose-dependent fashion without affecting the binding of von Willebrand (vWf ) factor. However, agglutination of formaldehyde-fixed platelets induced by ristocetin was not affected by monoclonal antibody LYP7. In addition, the binding of thrombin-activated platelets to neutrophils was inhibited by monoclonal antibody LYP7. These results strongly suggest that P-selectin, by promoting cell–cell contact, may play an active role in platelet–platelet interactions. 相似文献
8.
Plesner T; Ploug M; Ellis V; Ronne E; Hoyer-Hansen G; Wittrup M; Pedersen TL; Tscherning T; Dano K; Hansen NE 《Blood》1994,83(3):808-815
The cellular receptor for urokinase-type plasminogen activator (uPAR) binds pro-urokinase (pro-uPA) and facilitates its conversion to enzymatically active urokinase (uPA). uPA in turn activates surface- bound plasminogen to plasmin, a process of presumed importance for a number of biologic processes including cell migration and resolution of thrombi. We have previously shown that uPAR is expressed on the plasma membrane of circulating neutrophils, and we now report that stimulation with phorbol myristate acetate (PMA), FMLP, or tumor necrosis factor- alpha results in a rapid increase in the expression of uPAR. This process is accompanied by an increased cell-associated plasminogen activation after preincubation of neutrophils with pro-uPA in vitro. By subcellular fractionation of unstimulated neutrophils, 50% of uPAR is recovered in fractions containing latent alkaline phosphatase, corresponding to an intracellular compartment of easily mobilizable secretory vesicles distinct from both primary and specific granules, whereas the remaining 50% of uPAR is associated with a compartment eluting close to the specific granules. In contrast, the ligand pro-uPA is primarily (approximately 80%) found in the specific granules, but small amounts of pro-uPA/uPA (approximately 20%) coelute with latent alkaline phosphatase. Stimulation of neutrophils with FMLP results in translocation of uPAR as well as of pro-uPA from the secretory vesicles, whereas stimulation with PMA is required to translocate material from specific granules. Flow cytometry of neutrophils saturated with exogenous diisopropyl fluorophosphate-uPA shows a large excess (approximately 90%) of unoccupied uPAR on resting as well as FMLP- and PMA-stimulated neutrophils, suggesting a possible role for exogenous pro-uPA in providing neutrophils with a potential for plasminogen activation. These processes may be important for neutrophil extravasation and migration through extracellular matrix and for the contribution of neutrophils to resolution of thrombi. 相似文献
9.
OBJECTIVE: Little is known about the impact of fellowship training in primary care on subsequent research productivity. Our goal was to identify characteristics of research fellows and their training associated with subsequent publications and research funding. DESIGN: Mail survey in 1998. SETTING AND PARTICIPANTS: 1988-1997 graduates of 25 National Research Service Award primary care research fellowships in the United States. OUTCOME MEASURES: 1) Publishing 1 or more papers per year since the beginning of fellowship, or 2) serving as principal investigator (PI) on a federal or non-federal grant. RESULTS: One hundred forty-six of two hundred fifteen program graduates (68%) completed the survey. The median age was 38 years, and 51% were male. Thirty-two percent had published 1 or more papers per year, and 44% were PIs. Male gender (odds ratio [OR], 3.6; 95% confidence interval [95% CI], 1.4 to 9.2), self-reported allocation of 40% or more of fellowship time to research (OR, 4.4; 95% CI, 1.8 to 11.2), and having an influential mentor during fellowship (OR, 5.0; 95% CI, 1.5 to 17.2) were independently associated with publishing 1 or more papers per year. Fellows with funding as a PI were also more likely to have an influential mentor (OR, 3.0; 95% CI, 1.3 to 7.2). CONCLUSION: Primary care fellows who had influential mentors were more productive in research early after fellowship. Awareness of the indicators of early research success can inform the policies of agencies that fund research training and the curricula of training programs themselves. 相似文献
10.
B-chronic lymphocytic leukemia (CLL) patients frequently suffer from moderate to severe hypogammaglobulinemia. This complication is a serious cause of morbidity and mortality in this disorder. There is recent evidence that natural killer (NK) cells modulate B-cell immunoglobin (Ig) synthesis/secretion. The authors therefore evaluated the circulating NK cells from B-CLL patients on their ability to regulate mitogen-induced B-cell Ig synthesis. Blood, NK cells (CD16+, CD3-) from three B-CLL patients with hypogammaglobulinemia were able to clearly down-regulate the pokeweed mitogen (PWM)-induced-B-cell Ig secretion. In contrast, CD16+, CD3- cells from age-sex-matched controls or B-CLL patients with normal Ig were either nonregulatory or enhanced mitogen-induced B-cell Ig secretion. An alternative explanation for hypogammaglobulinemia in B-CLL patients is the immunomodulation of B- cell Ig production/secretion by CD16+, CD3- blood cells. 相似文献