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71.
Three commercial vessel dilators and a dilator of an improved design were tested during percutaneous catheterization in 16 mongrel dogs to evaluate arterial damage produced with their use. The results indicate that, although all dilators often produce arterial damage, the improved design produced much less damage. In addition, lesions were less severe overall. The dilator has been safely and successfully used in patients for percutaneous vessel catheterization for the past 30 years at the authors' institution.  相似文献   
72.
73.
This study was conducted to analyse the effect of childhood-onset diabetes mellitus on adult height. The height at time of diagnosis of 35 children with insulin-dependent diabetes mellitus (IDDM) was compared with growth reference data. Predictions of the adult height were made at the time of diagnosis using the target height and the Tanner-Whitehouse II method. The adult height was compared with both the predicted values and the height of healthy adults. The height at time of diagnosis of the prepubertal children was increased compared with growth reference data, in contrast to pubertal children who had normal heights. Only the prepubertal boys were taller at time of diagnosis. The adult height of the prepubertal patients was taller than growth reference data. The mean adult height in all patients did not differ significantly from the predicted heights. In conclusion, the increased height at the start of IDDM in prepubertal children persists until adulthood.  相似文献   
74.
Effects of short-term hypoxia on platelet counts of mice   总被引:3,自引:0,他引:3  
McDonald  TP; Cottrell  M; Clift  R 《Blood》1978,51(1):165-175
Recent studies have shown that long-term hypoxia causes decreased platelet counts in mice and short-term hypoxia increased platelet counts. In an attempt to explain the mechanism that increases platelet counts of mice after exposure to short-term hypoxia, we measured platelet counts, total circulating platelet counts (TCPC), total circulating platelet masses (TCPM), percentages of 35S incorporation, and platelet sizes. Platelet counts, as well as TCPC and TCPM of mice, increased after 1-3 days of hypoxia, but these values were decreased after 6-7 days of hypoxia. Although platelet counts were increased in hypoxic mice, the percentage 35S incorporation into platelets and platelet sizes did not show a concurrent increase. After 6 days of hypoxia, average platelet diameters began to increase as platelet counts decreased. Splenic release did not account for the increase in platelet counts of mice after short-term hypoxia. It seems possible, therefore, that megakaryocytes "shed" platelets into the circulation in response to hypoxia. The platelets that enter the circulation in response to short-term hypoxia are smaller and incorporate less 35S than platelets that are produced in response to acute thrombocytopenia.  相似文献   
75.
The growth fraction of tumors from patients with non-Hodgkin's lymphomas (NHL) has been shown to correlate with survival in retrospective studies. The growth fraction can be evaluated using immunohistochemical techniques employing the Ki-67 monoclonal antibody (MoAb) that marks a nuclear protein present in cycling cells. The purpose of this study was to evaluate the clinical utility of the Ki-67 MoAb for predicting survival. Using a prospective trial design in a multi-institutional cooperative trials group, the proliferative index, clinical outcome, and statistical correlations were independently assessed for previously untreated patients with advanced stages of intermediate- and high-grade histologies of NHL treated on Southwest Oncology Group study (SWOG 8516, Intergroup 0067). The proportion of Ki- 67-positive cells was determined on snap-frozen thin tissue sections. A proliferative index of 80% or greater, as determined from prior retrospective studies, identified a group of patients (18%) who had a poor outcome. Overall survival was significantly reduced in these patients with a high Ki-67-associated proliferative index compared with those with a low proliferative index (P = .001). One-year survival estimates were 82% (low proliferative index) versus 18% (high proliferative index). A multivariate regression analysis incorporating commonly used clinical prognostic features confirmed the independent effect of proliferation on survival (relative risk estimate 5.9; 95% confidence interval, 2.2, 16.1). The Ki-67 MoAb identifies a group of patients with rapidly fatal NHL for whom currently available chemotherapy is inadequate.  相似文献   
76.
77.

Background

To examine the clinical and economic burdens associated with delayed receipt of appropriate therapy among patients with Gram-negative bacteria (GNB) infections, stratified by antibiotic resistance status.

Materials and Methods

Retrospective analysis using the Premier Hospital Database. Adult admissions (July 2011-September 2014) with evidence of complicated urinary tract infection, complicated intra-abdominal infection, hospital-associated pneumonia, or bloodstream infection, length of stay (LOS) ≥1 days and a positive GNB culture from a site consistent with infection type (culture draw date?=?index date) were identified and stratified by antibiotic susceptibility to index pathogens. Delayed appropriate therapy was defined as no receipt of antibiotic(s) with relevant microbiological activity on or within 2 days of index date. Inverse probability weighting and multivariate regression analyses were used to estimate the association between delayed appropriate therapy and outcomes. Generalized linear models were used to evaluate postindex duration of antibiotic therapy, LOS and total in-hospital costs. Logistic models were used to evaluate discharge destination and in-hospital mortality/discharge to hospice.

Results

A total of 56,357 patients with GNB infections were identified (resistant, n?=?6,055; susceptible, n?=?50,302). Delayed appropriate therapy was received by 2,800 (46.2%) patients with resistant and 16,585 (33.0%) patients with susceptible infections. Using multivariate analysis, delayed appropriate therapy was associated with worse outcomes including ~70% increase in LOS, ~65% increase in total in-hospital costs and ~20% increase in the risk of in-hospital mortality/discharge to hospice, regardless of susceptibility status.

Conclusions

Our results suggest that outcomes in patients with GNB infections, regardless of resistance status, significantly improve if timely appropriate therapy can be provided.  相似文献   
78.
Dynamic exercise therapy in rheumatoid arthritis: a systematic review   总被引:7,自引:2,他引:7  
The aim of this systematic review was to determine the effectiveness of dynamic exercise therapy in improving joint mobility, muscle strength, aerobic capacity and daily functioning in patients with rheumatoid arthritis (RA). In addition, possible unwanted effects such as an increase in pain, disease activity and radiological progression were studied. A computer-aided search of the MEDLINE, Embase and SCISEARCH databases was performed to identify controlled trials on the effect of exercise therapy. Randomized trials were selected on the effect of dynamic exercise therapy in RA patients with an exercise programme fulfilling the following criteria: (a) intensity level such that heart rates exceeded 60% of maximal heart rate during at least 20 min; (b) exercise frequency > or = 2 a week; and (c) duration of intervention > or = 6 weeks. Two blinded reviewers independently selected eligible studies, rated the methodological quality and extracted data. Six out of 30 identified controlled trials met the inclusion criteria. Four of the six included studies fulfilled > or = 7/10 methodological criteria. Because of heterogeneity in outcome measures, data could not be pooled. The results suggest that dynamic exercise therapy is effective in increasing aerobic capacity and muscle strength. No detrimental effects on disease activity and pain were observed. The effects of dynamic exercise therapy on functional ability and radiological progression are unclear. It is concluded that dynamic exercise therapy has a positive effect on physical capacity. Research on the long-term effect of dynamic exercise therapy on radiological progression and functional ability is needed.   相似文献   
79.
胰岛ε细胞的研究进展   总被引:3,自引:0,他引:3  
胰腺由外分泌组织和内分泌组织2个部分所组成,两者在机体能量平衡和营养代谢调节中发挥重要的作用.胰岛是胰腺组织中重要的内分泌功能单位,胰岛的发育和分化过程涉及一个复杂而精细的分子调控网络体系,其中包括许多转录因子的参与.经典的胰岛内分泌细胞包括α细胞、β细胞、δ细胞及PP细胞,分别产生胰升糖素、胰岛素、生长抑素及胰多肽(PP),各种胰岛细胞之间的相互调节在维持血糖稳态中具有重要的意义.表达ghrelin 的ε细胞是一种新近发现和命名的胰岛细胞类型.现着重对胰岛ε细胞的发现过程、形态学特点及生物学作用进行介绍.  相似文献   
80.

Purpose

Clinicians and stewardship programs are challenged with positioning of novel, higher priced antibiotic agents for the treatment of clinical infections. We developed a decision-analytic model to describe costs, including drug, total treatment costs, and health care outcomes, associated with telavancin (TLV) compared with vancomycin (VAN) for patients with Staphylococcus aureus (SA) hospital-acquired bacterial pneumonia (HABP).

Methods

This decision-analytic model assessed the treatment of SA-HABP with TLV versus VAN. Data were obtained from the ATTAIN (Assessment of Telavancin for Treatment of Hospital-Acquired Pneumonia) clinical trials on the following: the probability of clinical cure; probability of nephrotoxicity; and prevalence of polymicrobial infection (30%), methicillin-resistant Staphylococcus aureus (MRSA) (68%), and SA with VAN MIC ≥1 µg/mL (85%). Data on length of stay for cure (10 days), failure (10 additional days), and nephrotoxicity (3.5 days) were based on literature. Cost per treated patient and incremental cost-effectiveness ratio (ICER) per additional cure were calculated for SA-HABP and for monomicrobial SA-HABP. One-way sensitivity analyses were performed.

Findings

Patients with SA-HABP were sub-grouped by methicillin susceptibility (n = 140, 32%) or resistance (n = 293, 68%), and occurrence of polymicrobial (n = 128, 30%) vs monomicrobial (n = 305, 70%) infections. Under the base case, hospital cost for patients with HABP treated with TLV was $42,564 and with VAN, it was $42,296. Telavancin was associated with higher drug ($2082) and nephrotoxicity ($467) costs and lower intensive care unit (?$1738) and ventilator (?$114) costs. ICER was $4156 per additional cure. ICER was sensitive to probabilities of cure, length of treatment in cures, intensive care unit cost, TLV cost, and additional length of stay due to failure. For monomicrobial SA-HABP, TLV was associated with a net cost savings of $907 per patient and yielded economic dominance.

Implications

Our decision-analytic model suggests that TLV for monomicrobial SA-HABP is associated with higher drug acquisition costs but a favorable ICER relative to VAN, provided that effective antimicrobial stewardship limits therapy to 7 days. Sensitivity analyses suggest a potential economic benefit of TLV treatment with appropriate patient selection. Antimicrobial stewardship programs may be able to reduce total costs through judicious use of novel antimicrobial agents. ClinicalTrials.gov identifiers: NCT00107952 and NCT00124020.  相似文献   
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