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31.
Benzodiazepines (BZs) were introduced into clinical practice in the 1960's. The major indications for their use are to treat anxiety, as sedative‐hypnotics, anti‐convulsants, muscle relaxants and pre‐anaesthetics. They replaced barbiturate tranquillisers and hypnotics which have significant and well‐documented dependence and overdose risks (Dupont & Saylor, 1991). Initially the BZs were thought not to induce dependence, to be of low overdose risk and to be relatively free of adverse side‐effects. However, during the 1970's it became apparent that these drugs do have quite serious adverse effects, especially in the elderly fluergens, 1993), and that dependence and withdrawal symptoms are not uncommon. Regular use of BZs, at normally prescribed doses, can lead to dependence in patients who do not abuse either BZs or other drugs (Owen & Tyrer, 1983). Dependence can develop in as little as 6–8 weeks' continuous administration (Lader & Petursson, 1983), and may persist for many months (Ashton, 1984). Symptoms include anxiety, insomnia, depression, aches and pains, muscle spasm, gastrointestinal disorders, and increased sensitivity to light sound & touch (Petursson & Lader, 1981; Ashton, 1984). At the same time the problems of drug interactions, whereby polydrug users add BZs to their drug cocktails, have brought them to the attention of the criminal justice system. This paper will review the mechanisms of action and patterns of use of BZs in Australia. The major adverse effects of BZs, on psychomotor skills and memory, in addition to the less common paradoxical effects on aggressive behaviour, will be discussed. The wide‐spread, long‐term use of these drugs, at least by certain groups, has consequences for the criminal justice system.  相似文献   
32.
33.

Purpose

The main purpose of this study is to establish which of two methods is more reliable in glenoid assessment for instability in pre-operative planning. Accordingly, we have studied the intra- and inter-observer reliability of glenoid parameters with the use of two-dimensional (2D) and three-dimensional (3D) reconstructed computed tomography (CT) images.

Methods

One hundred glenoids were measured with the use of 2D-CT and 3D-CT (in 3D orientation) by two independent observers (one experienced and one inexperienced). Measurements were repeated after one week for 30 randomly selected glenoids.

Results

The intra-class correlation coefficient (ICC) for inter-observer reliability was significantly greater for 3D-CT (0.811 to 0.915) than for 2D-CT (0.523 to 0.925). All intra-observer reliability values for 3D-CT were near perfect (0.835 to 0.997), while those for 2D-CT were less reliable (0.704 to 0.960). A dependent t-test showed that, for both observers, almost all glenoid parameters (except R and d) differed significantly (p?<?0.05) between 2D and 3D measurement methods.

Conclusions

Therefore, it can be concluded that 3D glenoid reconstructions are more reliable for glenoid bone loss assessment than 2D-CT. The results suggest that quantifying a glenoid defect with the use of 2D image only—even if performed by an experienced orthopaedic surgeon—is prone to errors. Differences in measurements between and within observers can be explained by plane setting and identifying glenoid rim in 2D-CT. Accordingly, we recommend that glenoid measurements should be performed in 3D orientation using 3D reconstruction obtained from CT images for pre-operative assessments, which are crucial for surgical planning.
  相似文献   
34.
S Lee  ; D Naime  ; M Reid  ; C Redman 《Transfusion》1997,37(10):1035-1038
BACKGROUND: The Kell blood group system consists of at least 21 antigens, which may be classified into five sets of alleles and at least 10 independently expressed antigens. The molecular basis of four of the five sets of alleles has been described; point mutations in KEL leading to amino acid substitutions characterize the alleles. In this study, the point mutation associated with the remaining allele, KEL14/KEL24, was determined. STUDY DESIGN AND METHODS: The 19 exons of KEL were amplified from genomic DNA by a polymerase chain reaction (PCR) procedure. The PCR products were sequenced. DNA sequences from unrelated KEL:14,24 and KEL:-14,24 individuals were compared to the DNA sequence of the common KEL:14,-24 phenotype. RESULTS: DNA from the KEL:14,24 person yielded both G and C at nt 659, indicating an Arg and Pro polymorphism in amino acid residue 180 of Kell protein. DNA from the KEL:-14,24 person had a G659C mutation in exon 6, indicating an Arg180Pro substitution. The G659C change introduces an Hae III restriction enzyme site, which was used to confirm the base mutations by restriction fragment length polymorphism analysis of the PCR products. CONCLUSION: A G659C mutation, predicting an Arg180Pro change in Kell protein, is associated with the KEL14/KEL24 allele.  相似文献   
35.
The mound known as Çayönü Tepesi (38° 16′ N; 39° 43′ E) in southeastern Turkey is one of the increasing number of early village sites which, since World War II, have been excavated archeologically in greater southwestern Asia. The evidence recovered in the autumn 1972 campaign of the Joint Istanbul-Chicago Prehistoric Project is briefly described, with particular attention to Çayönü's architectural remains, which are most remarkable, considering the site's date of about 7000 B.C. There was evidence of domesticated food plants from the beginning but animal domesticates were not present (save the dog) until later in the major prehistoric phase of occupation.  相似文献   
36.
OBJECTIVES: To evaluate risk factors for ventilator-associated pneumonia (VAP), as well as its influence on in-hospital mortality, resource utilization, and hospital charges. DESIGN: Retrospective matched cohort study using data from a large US inpatient database. PATIENTS: Patients admitted to an ICU between January 1998 and June 1999 who received mechanical ventilation for > 24 h. MEASUREMENTS: Risk factors for VAP were examined using crude and adjusted odds ratios (AORs). Cases of VAP were matched on duration of mechanical ventilation, severity of illness on admission (predicted mortality), type of admission (medical, surgical, trauma), and age with up to three control subjects. Mortality, resource utilization, and billed hospital charges were then compared between cases and control subjects. RESULTS: Of the 9,080 patients meeting study entry criteria, VAP developed in 842 patients (9.3%). The mean interval between intubation, admission to the ICU, hospital admission, and the identification of VAP was 3.3 days, 4.5 days, and 5.4 days, respectively. Identified independent risk factors for the development of VAP were male gender, trauma admission, and intermediate deciles of underlying illness severity (on admission) [AOR, 1.58, 1.75, and 1.47 to 1.70, respectively]. Patients with VAP were matched with 2,243 control subjects without VAP. Hospital mortality did not differ significantly between cases and matched control subjects (30.5% vs 30.4%, p = 0.713). Nevertheless, patients with VAP had a significantly longer duration of mechanical ventilation (14.3 +/- 15.5 days vs 4.7 +/- 7.0 days, p < 0.001), ICU stay (11.7 +/- 11.0 days vs 5.6 +/- 6.1 days, p < 0.001), and hospital stay (25.5 +/- 22.8 days vs 14.0 +/- 14.6 days, p < 0.001). Development of VAP was also associated with an increase of > $40,000 USD in mean hospital charges per patient ($104,983 USD +/- $91,080 USD vs $63,689 USD+/- $75,030 USD, p < 0.001). CONCLUSIONS: This retrospective matched cohort study, the largest of its kind, demonstrates that VAP is a common nosocomial infection that is associated with poor clinical and economic outcomes. While strategies to prevent the occurrence of VAP may not reduce mortality, they may yield other important benefits to patients, their families, and hospital systems.  相似文献   
37.
38.
The foetal heart rate (FHR) response to uterine contractions is crucial to detect foetal distress by electronic FHR monitoring during labour. We are developing a new automated system (OxSys) for decision support in labour, using the Oxford database of intrapartum FHR records. We describe here a novel technique for automated detection of uterus contractions. In addition, we present a comparison of the new method with four other computerised approaches. During training, OxSys achieved sensitivity above 95% and positive predictive value (PPV) of up to 90% for traces of good quality. During testing, OxSys achieved sensitivity = 87% and PPV = 75%. For comparison, a second clinical expert obtained sensitivity = 93% and PPV = 80%, and all other computerised approaches achieved lower values. It was concluded that the proposed method can be employed with confidence in our study on foetal health assessment in labour and future OxSys development.  相似文献   
39.

Introduction  

The assessment of adrenal function in critically ill patients is problematic, and there is evidence to suggest that measurement of tissue glucocorticoid activity may be more useful than estimation of plasma cortisol concentrations. Interstitial cortisol concentrations of cortisol represent the available pool of glucocorticoids able to enter the cell and bind to the glucocorticoid receptor. However the concentrations of plasma cortisol may not accurately reflect interstitial concentrations. We elected to perform a preliminary study into the feasibility of measuring interstitial cortisol by microdialysis, and to investigate the relationship between total plasma cortisol, free plasma cortisol and interstitial cortisol in patients with severe burns.  相似文献   
40.
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