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991.
Background: Point of Care Ultrasound (PoCUS) is well established within emergency medicine, however, the availability of formal training for other clinical disciplines is limited. Memorial University has established a cost-efficient, multidisciplinary PoCUS training program focusing on training residents’ discipline-specific ultrasound skills. This study evaluates the skills, knowledge, and attitudes of residents who participated in the program.

Methods: Analysis was conducted using a mixed-methods, sequential exploratory approach. Initially, a focus group of seven first year residents was conducted to generate themes that were used to guide development of a survey administered to residents over a two-year period.

Results: Thirty residents responded to the survey (response rate 63.8%) with 53.3% meeting the training requirements for focused assessment using sonography in trauma, 43.3% for pleural effusion, 40.0% for aortic aneurysms, and 40.0% for cardiac scans. Early pregnancy assessment was the skill of least interest with 46.6% not interested. Over half the residents (53.6%) agreed or strongly agreed that a multidisciplinary program met their needs while 21.4% disagreed. The focus group found the multidisciplinary approach adequate.

Conclusions: A single PoCUS curriculum has been shown to meet the needs and expectations of a majority of residents from multiple disciplines. It can enhance collaboration and bridge gaps between increasingly compartmentalized practices of medicine.  相似文献   

992.
Previous studies have demonstrated that specialists and generalists differ in the evaluation and management of asthma especially in terms of use of objective testing. We speculated that there also may be differences in the diagnosis and management of exercise-induced respiratory complaints. An Internet survey was sent to samples of pulmonologists and family physicians. Our data suggests that pulmonologists are much more likely to order bronchoprovocation testing than family physicians, and family physicians are more likely to start any empiric therapy than perform bronchoprovocation testing when exercise-induced bronchospasm is suspected. These differences may lead to inaccurate or missed diagnoses and unnecessary morbidity.  相似文献   
993.
Cognitive functioning in sober social drinkers: a review and critique   总被引:2,自引:0,他引:2  
There have been recent scientific reports of an association between amount of alcohol drunk per occasion and inefficiencies in performance on cognitive-perceptual tests. The empirical evidence and six different hypotheses concerning the causal nature of the obtained relationships are reviewed. The findings are variable and seldom reproducible. There is no consistent evidence to support any of the causality hypotheses. Despite these limitations, the problem is of sufficient social, economic, legal and humanistic importance that continued investigation is warranted. The complexity of the problem addressed demands careful consideration of a number of relevant experimental variables. Guidelines for future research are offered as regards sampling, subject characteristics, measurement of cognitive-perceptual functioning and drinking history, as well as methods of analysis. The possible confounding roles of family history of alcoholism, anxiety, native intelligence and past educational experiences are stressed. The need for prospective studies is emphasized.  相似文献   
994.
1. In electrophysiological experiments in spinalized rats, mu- and kappa-opioids were tested intravenously on the responses of single motoneurones to electronically controlled, alternating noxious heat and noxious pinch stimuli. The effects of mu- and kappa-opioids were compared with those of the general anaesthetic alpha-chloralose and the dissociative anaesthetic/PCP ligand ketamine. 2. The kappa-opioids U-50,488 (0.5-16 mgkg-1 i.v.) and tifluadom (0.05-1.6 mgkg-1 i.v.) had very similar actions to the mu-opioid fentanyl (0.5-16 micrograms kg-1 i.v.). Thus all three agonists reduced thermal and mechanical nociceptive reflexes in parallel and in a dose-dependent manner, but only so long as neuronal responses to the alternating stimuli elicited similar excitability levels in the neurone under study. Ketamine (0.5-16 mgkg-1 i.v.) had similar actions to the opioids whereas alpha-chloralose (20 mgkg-1 i.v.) had very little effect on neuronal responsiveness. 3. Apparently 'selective' depressions by both mu- and kappa-opioids could be orchestrated by a deliberate mismatch of the intensities of alternating noxious heat and pinch stimuli; as measured by neuronal firing rate, the weaker of the responses to either type of stimulus was invariably reduced to a greater degree. 4. Similar 'selectivity' could be demonstrated for both mu- and kappa-ligands when the weaker and stronger responses were of the same modality, being applied by the same pincher device but with alternating applied force. 5. It is concluded that the 'selective' spinal actions of kappa-opioids seen in non-thermal over thermal behavioural models of nociception is likely to be related to the relative intensities, rather than the modalities, of the noxious stimuli used. The validity of the interpretation of results obtained in such behavioural studies is discussed.  相似文献   
995.
A histopathologic review was undertaken of 293 patients with breast cancer treated by local tumor excision and radical radiotherapy. In a 6-year period, there were 37 local treatment failures with 16 deaths, and an additional 20 patients died without local recurrence. Pathologic data were available for 272 patients. Multivariate analysis indicated that the pathologic features in an invasive tumor most predictive for local recurrence were the combination of a high proportion of intraduct carcinoma with extensive necrosis (comedocarcinoma). Of 18 patients with these features, nine have had early local recurrence (a risk of 50% with these features vs 10% in those without), and four have died (a risk of 22% against 12%). Despite the short follow-up, the results already appear significant, and the study is ongoing. The importance of comedonecrosis in the intraduct component as a prognostic indicator in invasive carcinoma of the breast is not widely recognized and might constitute a relative contraindication to conservative treatment of the breast.  相似文献   
996.
In planning psychopharmacologic treatment of patients with borderline personality disorder (BPD), three partially validated subtypes should be considered. The validity of the schizotypal subtype is supported by their favorable response to neuroleptics as well as by familial and genetic studies. The validity of emotionally unstable character disorder (EUCD) is supported by the presence of neurological soft signs, their negative response to antidepressants, and their positive response to chlorpromazine and lithium. The data presented in this paper suggest that some patients who meet borderline criteria and have atypical depression (patients meeting DSM-III-R criteria for major depression or dysthymia who have reactive mood and any atypical symptoms) clearly benefit from treatment with antidepressant medication. Although some patients with atypical depression who meet borderline criteria will improve with tricyclic therapy, a significantly greater proportion will improve with the monoamine oxidase inhibitor (MAOI), phenelzine.  相似文献   
997.
1. 3-Aminopropylphosphinic acid, a gamma-aminobutyric acid (GABA) analogue, was tested for activity on guinea-pig isolated ileum and rat isolated anococcygeus muscle preparations. The effects of 3-aminopropylphosphinic acid were compared with those of GABA and baclofen. 2. In the electrically stimulated ileum, 3-aminopropylphosphinic acid, like GABA and baclofen, caused a concentration-dependent inhibition of the cholinergic twitch contraction, the IC50 value being 1.84 +/- 0.23 microM (n = 12). Unlike GABA, but like baclofen, 3-aminopropylphosphinic acid did not produce an initial contraction. 3. The inhibitory effects of 3-aminopropylphosphinic acid and baclofen in the guinea-pig ileum were not significantly antagonized by bicuculline (10 microM), phentolamine plus propranolol (both 1 microM), yohimbine (1 microM), naloxone (1 microM), impromidine (1 microM) or 8-phenyltheophylline (10 microM). The inhibitory effects of 3-aminopropylphosphinic acid, but not of baclofen, were however antagonized by phaclofen (500 microM). In addition the effects of 3-aminopropylphosphinic acid were abolished by baclofen desensitization in the guinea-pig ileum. 4. 3-Aminopropylphosphinic acid, GABA and baclofen reduced the twitch contraction evoked by electrical field stimulation in the rat anococcygeus muscle. The IC50 for 3-aminopropylphosphinic acid inhibition of the anococcygeus contraction was 0.89 +/- 0.15 microM (n = 8). 5. It is concluded that 3-aminopropylphosphinic acid is a potent, selective GABAB agonist, being seven times more potent than baclofen in the guinea-pig ileum and five times more potent than baclofen in the rat anococcygues muscle preparations.  相似文献   
998.
The benzimidazole sulfoxide class of antisecretory H+/K+-ATPase inhibitors need to possess high stability under neutral physiological conditions yet rearrange rapidly at low pH to the active sulfenamide 2. Since the initial reaction involves internal nucleophilic attack by the pyridine nitrogen, control of the pyridine pKa is critical. In this paper we show that by utilizing the powerful electron-donating effect of a 4-amino substituent on the pyridine, moderated by the electron-withdrawing effect of a 3- or 5-halogen substituent, a combination of high potency (as inhibitors of histamine-stimulated gastric acid secretion) and good stability under physiological conditions can be obtained. Furthermore, the role of the steric interaction between the 3/5-substituents and the 4-substituent in modifying the electron-donating ability of the 4-amino group is exemplified, and additional factors affecting stability are identified. One compound, in particular, 2-[[(3-chloro-4-morpholino-2- pyridyl)methyl]sulfinyl]-5-methoxy-(1H)-benzimidazole (3a, SK&F 95601), was chosen for further development and evaluation in man.  相似文献   
999.
The reactions of O2-. in aqueous solutions of pyrogallol 1 and the antioxidant n-propyl gallate 2 have been studied. In both cases the initial reaction gives hydrogen peroxide and the corresponding phenoxyl radical (k(1 + O2-.) = 3.4 x 10(5), k(2 + O2-.) = 2.6 x 10(5) dm3 mol-1S-1). These phenoxyl radicals have been produced independently by reacting 1 and 2 with Br2-. and their spectra and first pKa values measured (pKa(phenoxyl radical from 1) = 5.1, pKa(phenoxyl radical from 2) = 4.1). It is necessary to correct the observed spectra for the contribution of the H-adducts, formed by the reaction of radiolytically produced H atoms with the substrates (k(1 + H) = 2.5 x 10(9), k(2 + H) = 3.8 x 10(9) dm3 mol-1 S-1). The H-adduct spectra are given. In the reactions of O2-. with the substrates the initial transient absorbances are characteristic of the phenoxyl radicals; however at longer times a new transient absorbing around 500 nm (epsilon congruent to 10(4) dm3 mol-1 cm-1) appears. This is believed to be the deprotonated hydroxy-orthoquinone, formed by the reaction of phenoxyl radicals with O2-. (k congruent to 1.5 x 10(8) dm3 mol-1 S-1, from kinetic curve-fitting). The absorbance due to the hydroxy-orthoquinones decays by first-order kinetics (1.6 x 10(2) in the case of 1 and 1.1 x 10(2) s-1 in the case of 2). This is thought to be mainly the result of the conversion of the hydroxy-orthoquinone into its hydrate. Similar experiments were carried out with catechol and ethyl protocatechuate. The chemistry appears to be similar to that of the pyrogallol derivatives. The rate constant for reaction of these compounds with O2-. is, however, only less than or equal to x 10(4) dm3 mol-1 s-1.  相似文献   
1000.
Primary subglottic cancer: results of radical radiation therapy   总被引:1,自引:0,他引:1  
Between October 1964 and December 1985, six patients with primary squamous cell carcinoma of the subglottis were treated with radical radiation therapy at the University of Florida. The disease was staged as Tis (one patient), T2N0 (two patients), and T4N0 (three patients). Local control was achieved with irradiation in four patients (66%) who were observed for 3.5, 4, 4, and 5 years after radiation therapy. Two patients whose tumors recurred at the primary site underwent salvage laryngectomy, which was successful in one patient.  相似文献   
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