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641.

Background

Many self-attending patients make inappropriate use of accident and emergency departments.

Aim

To determine whether a new care method consisting of the involvement of a GP during the day with the staff of the accident and emergency department of an academic city hospital and application of the Nederlands Triage Systeem by a practice nurse is more effective than usual care.

Design

Before and after intervention design.

Setting

Accident and emergency department in the VU University Medical Center in Amsterdam.

Method

Participants were patients (n = 1527) attending the accident and emergency department without a referral, on weekdays from 10.00–17.00 hours, from 1 November 2006 to 30 April 2007. The intervention consisted of a new care method that combined the involvement of a GP in the accident and emergency department and allocation of patients by triage to either the GP or the accident and emergency department physician. Main outcome measures were patient satisfaction, number and type of additional examinations, quality of diagnosis, process time, and treatment time.

Results

Patient satisfaction with the treatment increased significantly. Compared to the usual care method, this new care method resulted in a 13% decrease in additional examinations. The percentage of incorrect diagnoses (1 %), as a measure of quality of care, was similar with the two methods. The mean process time decreased from 93 to 69 minutes (P<0.001). The mean treatment time decreased from 60 to 35 minutes (P<0.001).

Conclusion

The new care method resulted in greater patient satisfaction and maintained the quality of care, with fewer additional examinations. It reduced both the process time and the treatment time.  相似文献   
642.
The mucopolysaccharidoses are a clinically heterogeneous group of lysosomal storage disorders presenting with broad multi-system disease and a continuous range of phenotypes. Currently, there are no objective biomarkers of MPS disease that clearly reflect disease severity or therapeutic responsiveness. Using proteomic studies in the murine MPS I model, we have identified the formation of the heparin cofactor II-thrombin (HCII-T) complex, a well-known serine protease inhibitor (serpin)-serine protease complex, as an informative biomarker for MPS I. MPS I patients showed a range of serum HCII-T concentrations from 46,000-208,600 pM, whereas the control values varied from 115.1-398.0 pM. HCII-T complex was also elevated in plasma from MPS I patients and mice. The degree of HCII-T complex formation appears to correlate with disease severity and is responsive to therapy. In addition to its role as a biomarker, the discovery of increased serpin-serine protease complex formation provides a valuable insight into possible pathophysiological mechanisms of MPS disease.  相似文献   
643.
644.
Polycomb-group (PcG) genes preserve cell identity by gene silencing, and contribute to regulation of lymphopoiesis and malignant transformation. We show that primary nodal large B-cell lymphomas (LBCLs), and secondary cutaneous deposits from such lymphomas, abnormally express the BMI-1, RING1, and HPH1 PcG genes in cycling neoplastic cells. By contrast, tumor cells in primary cutaneous LBCLs lacked BMI-1 expression, whereas RING1 was variably detected. Lack of BMI-1 expression was characteristic for primary cutaneous LBCLs, because other primary extranodal LBCLs originating from brain, testes, and stomach were BMI-1-positive. Expression of HPH1 was rarely detected in primary cutaneous LBCLs of the head or trunk and abundant in primary cutaneous LBCLs of the legs, which fits well with its earlier recognition as a distinct clinical pathological entity with different clinical behavior. We conclude that clinically defined subclasses of primary LBCLs display site-specific abnormal expression patterns of PcG genes of the HPC-HPH/PRC1 PcG complex. Some of these patterns (such as the expression profile of BMI-1) may be diagnostically relevant. We propose that distinct expression profiles of PcG genes results in abnormal formation of HPC-HPH/PRC1 PcG complexes, and that this contributes to lymphomagenesis and different clinical behavior of clinically defined LBCLs.  相似文献   
645.
Heparan sulfates (HS), a class of glycosaminoglycans, are long linear complex polysaccharides covalently attached to a protein core. The HS molecules are made up of repeating disaccharides onto which modification patterns are superimposed. This results in a large structural heterogeneity and forms the basis of specific interactions of HS toward a vast array of proteins, including growth factors and proteases. To study HS heterogeneity in the lung, we used phage display technology to select seven antibodies against human lung HS. Antibodies reacted with HS/heparin, but not with other glycosaminoglycans or polyanions. Sulfate groups were essential for antibody binding. The amino acid sequence of the antibodies was established, the complementarity determining region 3 of the heavy chain containing basic amino acids. The antibodies defined HS epitopes with a characteristic tissue distribution. Antibody EV3A1 primarily stained macrophages. Other antibodies primarily stained basement membranes, but with different preference toward type of basement membrane. Antibody EV3C3 was the only antibody which clearly reacted with bronchiolar epithelial cells. In human lung parenchyma, basic fibroblast growth factor and vascular endothelial growth factor were largely bound by HS. Some antibodies blocked a basic fibroblast growth factor-binding site of HS, and one antibody blocked a vascular endothelial growth factor-binding site of heparin. Taken together, these data suggest a specific role for HS epitopes in human lung. The antibodies obtained may be valuable tools to study HS in pulmonary diseases.  相似文献   
646.
Human neuronal cells contain mutant beta-amyloid precursor protein (APP) and ubiquitin B (UBB) mRNAs, in which dinucleotide deletions ('Delta') are generated in/around GAGAG-motifs by an unknown mechanism referred to as 'Molecular Misreading.' The encoded frameshifted (+1) proteins accumulate in the neuropathological hallmarks of Alzheimer's disease (AD) and in other neurodegenerative and age-related diseases. To measure the concentration of Delta mRNAs, we developed a highly sensitive and specific assay, utilizing peptide nucleic acid-mediated PCR clamping, followed by cloning and colony hybridization with sequence-specific oligonucleotide probes. We found only a few molecules of Delta mRNA/microg of cellular RNA, at levels <10(-5) to 10(-6) x the concentration of WT mRNA, in RNA extracted from: (i) cultured human neuroblastoma cells grown under a variety of conditions, (ii) the frontal half of brains from wild type and XPA(-/-) DNA repair-deficient mice, and (iii) post-mortem temporal cortices from humans. Importantly, in RNA from the temporal cortices of AD and Down Syndrome patients that contain betaAPP+1 and UBB+1 immunoreactive cells, we found the same low levels of Delta mRNA. We infer that the accumulation of +1 proteins in neurons of these patients is not caused by an increase in the concentration of Delta mRNAs.  相似文献   
647.
In previous studies we have shown in Alzheimer's disease (AD) an enhanced nuclear estrogen receptor (ER) alpha expression in the cholinergic basal forebrain nuclei, i.e. the vertical limb of the diagonal band of Broca (VDB) and the nucleus basalis of Meynert (NBM), and in a number of hypothalamic nuclei, i.e. the supraoptic nucleus (SON), the infundibular nucleus (INF), the medial mamillary nucleus (MMN). We aimed at determining whether the increase in nuclear ERalpha seen in AD patients was related to a rise in local production of estrogens by aromatase (P-450arom), which is a key enzyme that catalyzes the biosynthesis of estrogens from precursor aromatizable androgens. We confirmed for the first time the presence of aromatase mRNA in neurons and glial cells in the human NBM and the tuberomamillary nucleus by RT-QPCR using laser microdissection. Enhanced aromatase immunoreactivity (ir) was indeed observed in the NBM in AD. However, in contrast a decreased aromatase-ir was found in the SON, INF and MMN of AD patients. In addition, P-450arom-ir was clearly diminished in ependymal and choroid plexus cells in AD. While an increase in aromatase-ir was found in the NBM and SON during normal aging, a decrease in staining was observed in the MMN. No sex differences in young control, elderly control or AD patients were present in any of the nuclei studied. In conclusion, brain P-450arom-ir and the relationship of its regulation with plasma sex steroid levels, estrogen and androgen receptors in the human hypothalamus and basal forebrain are region-specific.  相似文献   
648.
649.
Objective. To determine whether sulfasalazine (SSZ) at a dosage of 2,000 mg/day is effective in the treatment of reactive arthritis (ReA) that has been unresponsive to nonsteroidal antiinflammatory drug (NSAID) therapy. Methods. One hundred thirty-four patients with ReA who had failed to respond to NSAIDs were recruited from 19 clinics, randomized (double-blind) to receive either SSZ or placebo, and followed up for 36 weeks. The definition of treatment response was based on joint pain/tenderness and swelling scores and physician and patient global assessments. Results. Longitudinal analysis revealed improvement in the patients taking SSZ compared with those taking placebo, which appeared at 4 weeks and continued through the trial (P = 0.02). At the end of treatment, response rates were 62.3% for SSZ treatment compared with 47.7% for placebo treatment. The Westergren erythrocyte sedimentation rate declined more with SSZ treatment than with placebo (P < 0.0001). Adverse reactions were fewer than expected and were mainly due to nonspecific gastrointestinal complaints. Conclusion. SSZ at a dosage of 2,000 mg/day is well tolerated and effective in patients with chronically active ReA.  相似文献   
650.
Objective. To determine whether sulfasalazine (SSZ) at a dosage of 2,000 mg/day is effective for the treatment of active ankylosing spondylitis (AS) that is not controlled with nonsteroidal antiinflammatory drug therapy. Methods. Two hundred sixty-four patients with AS were recruited from 15 clinics, randomized (double-blind) to SSZ or placebo treatment, and followed up for 36 weeks. Treatment response was based on morning stiffness, back pain, and physician and patient global assessments. Results. While longitudinal analysis revealed a trend favoring SSZ in the middle of treatment, no difference was seen at the end of treatment. Response rates were 38.2% for SSZ and 36.1% for placebo (P = 0.73). The Westergren erythrocyte sedimentation rate declined more with SSZ treatment than with placebo (P < 0.0001). AS patients with associated peripheral arthritis showed improvement that favored SSZ (P = 0.02). Adverse reactions were fewer than expected and were mainly due to nonspecific gastrointestinal complaints. Conclusion. SSZ at a dosage of 2,000 mg/day does not seem to be more effective than placebo in the treatment of AS patients with chronic, longstanding disease. SSZ is well tolerated and may be more effective than placebo in the treatment of AS patients with peripheral joint involvement. This effect is more pronounced in treatment of the peripheral arthritis in this subgroup of AS patients.  相似文献   
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