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91.
Acoustic analysis of gradient-coil noise in MR imaging 总被引:4,自引:0,他引:4
A survey was conducted of acoustic noise levels in magnetic resonance (MR) imaging systems. Static magnetic flux and radio-frequency pulses did not affect the function of shielded sound-pressure detection equipment. Noise levels were measured at bore isocenter during a variety of imaging sequences in six MR imaging systems with magnetic fields of 0.35-1.5 T. Measured noise ranged from 82 to 93 dB on the A-weighted scale and from 84 to 103 dB on the linear scale. Noise levels increased during sequences employing thinner section thickness and shorter repetition and echo times and were independent of field strength. Gradient-coil noise in MR imaging is an annoyance but is well within safety guidelines. 相似文献
92.
Antegrade internal ureteral stenting: a technical refinement 总被引:2,自引:0,他引:2
A pliable, easy to place, double pigtail, internal ureteral stent made of elastomeric polyurethane is described. The tapered distal pigtail end minimizes bladder irritation and the combination of a pusher and absorbable suture enables optimal placement of the proximal pigtail end in the renal pelvis. Ten stents used in eight patients remained functional without bladder irritation for a mean period of 8 months (range, 2-14 months). 相似文献
93.
94.
Pulmonary nodules studied by computed tomography 总被引:2,自引:0,他引:2
The authors analyzed 177 pulmonary nodules using thin-section computed tomography (CT), calculating the representative CT number (RCT#) from a computer printout. None of the 96 malignant nodules had an RCT# greater than 151 H. Of the 81 benign nodules, 14 were shown to be calcified by conventional radiography and had an RCT# ranging from 763 and 1,023 H. Thirty had an RCT# greater than 200 H; this included 24 which showed no calcification on conventional tomograms. The remaining 37 benign nodules had an RCT# less than 200 H; 6 of them were hamartomas, including 2 which were diagnosed as such due to their fat content. 相似文献
95.
Kumar SR Sathish Venkata Bhaskara Rao Kokati 《Asian Pacific Journal of Tropical Biomedicine》2012,2(10):787-792
Objective
To investigate the antibacterial activity of marine actinobacteria against multidrug resistance Staphylococcus aureus (MDRSA).Methods
Fifty one actinobacterial strains were isolated from salt pans soil, costal area in Kothapattanam, Ongole, Andhra Pradesh. Primary screening was done using cross-streak method against MDRSA. The bioactive compounds are extracted from efficient actinobacteria using solvent extraction. The antimicrobial activity of crude and solvent extracts was performed using Kirby-Bauer method. MIC for ethyl acetate extract was determined by modified agar well diffusion method. The potent actinobacteria are identified using Nonomura key, Shirling and Gottlieb 1966 with Bergey''s manual of determinative bacteriology.Results
Among the fifty one isolates screened for antibacterial activity, SRB25 were found efficient against MDRSA. The ethyl acetate extracts showed high inhibition against test organism. MIC test was performed with the ethyl acetate extract against MDRSA and found to be 1 000 µg/mL. The isolated actinobacteria are identified as Streptomyces sp with the help of Nonomura key.Conclusions
The current investigation reveals that the marine actinobacteria from salt pan environment can be able to produce new drug molecules against drug resistant microorganisms. 相似文献96.
97.
Multiple myeloma is a clonal disorder of plasma cells which is considered incurable with currently available therapies. Substantial advances have been achieved in the past decade with the identification of cellular mechanisms that confer drug resistance. This has resulted in newer agents such as arsenic trioxide (Trisenoxt), lenalidomide (Revlimid) and bortezomib (Velcade) with promising activity in this disease. In this review article we will outline the history, mechanisms of action, pharmacology, and clinical trials of arsenic trioxide in multiple myeloma. 相似文献
98.
Objective: Young people with asthma often lack engagement in self-management. Smartphone apps offer an attractive, immediate method for obtaining asthma information and self-management support. In this research we developed an evidence-based asthma app tailored to young peoples needs, created using a participatory design approach to optimize user engagement. This paper describes the participatory design process. Methods: This multi-phased research included concept generation and ideation of app design by young people with asthma, and development of asthma information by the research team. Clinical review was sought regarding safety and accuracy of app content. Participants suggestions for improvement and any problems with the app were logged throughout. Our young co-designers were invited back to test a high fidelity prototype app using a “think aloud” process and completed a usability questionnaire. Results: Twenty asthma patients aged 15-24 years contributed to the initial app design. Three respiratory specialists and two pharmacists suggested minor corrections to clinical terminology in the app which were all incorporated. Nine co-designers acted as expert reviewers of the prototype app, of whom eight completed a usability questionnaire. Median usability scores (maximum score 6) indicated high satisfaction with app content, usefulness and ease of use [median item score 5.3 (range 4.7-6.0)]. All feedback was incorporated to create an updated prototype app. Conclusions: A clinically sound asthma app has been developed which is considered highly acceptable to the young co-designers. A six-week test of the engagement, acceptability, and usefulness of the app in young people not involved in the participatory design will follow. 相似文献
99.
K Karthik SR Sundararajan J Dheenadhayalan S Rajasekaran 《Indian Journal of Orthopaedics》2011,45(1):33-38
Background:
Intra-articular loose bodies following simple dislocations can lead to early degeneration. Nonconcentric reduction may indicate retained loose bodies and offer a method to identify patients requiring exploration so that this undesirable outcome can be avoided.Materials and Methods:
One hundred and seventeen consecutive simple dislocations of the hip presenting to the hospital from January 2000 to June 2006 were assessed for congruency after reduction by fluoroscopic assessment of passive motion in the operating room as well as with good quality radiographs. Computerized tomography (CT) scan with 2-mm cuts was done for confirmation of reduction and to identify the anatomy of loose bodies. Patients with nonconcentric reduction underwent open exploration to identify the etiology of the dislocation and for removal of loose bodies. Thomson and Epstein clinical and radiological criteria were used to assess the outcome.Results:
Twelve of the one hundred and seventeen (10%) dislocations had incongruent reduction, which was identified by the break in Shenton’s line and increase in medial joint space in seven patients, increase in the superior joint space in three patients, or increase in the joint space as a whole in two patients. CT scan identified the origin of the osteocartilaginous fragment as being from the acetabulum in six patients, the femoral head in four, and from both in one. One patient had an inverted posterior labrum. Following debridement, congruent reduction was achieved in all patients. At an average follow-up of 5 years (range: 2 years 5 months to 8 years), the outcome as evaluated by Thompson and Epstein clinical criteria was excellent in eleven cases and good in one case; the radiological outcome was excellent in eight cases and good in four cases.Conclusions:
Intra-articular loose bodies were identified by nonconcentric reduction in 12 out of 117 patients with simple hip dislocation. Careful evaluation by fluoroscopy and good quality radiographs are indicated following reduction of hip dislocations. 相似文献100.
Lip cancer (140 ICD-9) is a form of oral cancer that has a distinctive global epidemiology. This review summarises global incidence rates for male and female lip cancer with the aid of cancer atlases. High male lip cancer rates are reported for regions of North America (12.7 per 100 000 per annum), Europe (12.0 per 100 000 per annum) and Oceania (13.5 per 100 000 per annum), while it is virtually unknown in parts of Asia. Factors commonly cited as important in the aetiology of lip cancer include solar radiation, tobacco smoking and viruses. An attempt is made to summarise the evidence for factors that may be important in lip carcinogenesis. While incidence rates are generally stable or falling among males worldwide, they are rising in many female populations. The aetiology of the disease is far from established and much information regarding its pathogenesis is based on anecdotal rather than case-controlled epidemiological evidence. The epidemiology of lip cancer supports the proposal that the lip should be considered as a distinct cancer site, rather than being included with other forms of intraoral cancer. 相似文献