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21.
We present a case of benign osteoblastoma of the occipital bone. Benign osteoblastoma is an uncommon primary bone tumor, which usually involves the vertebrae and the long bones. This tumor rarely develops in the calvaria, showing a preference for the temporal and frontal bones when it does. To the best of our knowledge, this case is only the eighth reported case of benign osteoblastoma confined to the occipital bone. A 20‐year‐old male presented with a mild tender mass lesion of the occipital area, just below the lambda. Plain X‐ray films and CT scans demonstrated an osteolytic mass surrounded by the sclerotic rim within the diploic space. MRI proved to be effective for the evaluation of the intracranial and intraosseous extensions of the tumor. However, it was very difficult to formulate a differential diagnosis against other osteoblastic tumors, or osteoid osteoma, in view of its radiological appearance. The final diagnosis was obtained by careful consideration of the histopathological characteristics of the tumor combined with its clinical and radiological features. Although generally regarded as benign, a complete resection is preferred over conventional curettage as this can guard against possible recurrence and malignant transformation.  相似文献   
22.
Seventy-four per cent of 428 patients referred to the glaucoma clinic at Concord Hospital exhibited intraocular pressure (IOP) asymmetry. There was a preponderance of left eyes, in that two-thirds of the patients with asymmetrical pressures had the higher IOP in the left eye. As the degree of asymmetry increased, this trend became more pronounced. In addition, the statistically significant difference between right and left mean IOP among the glaucoma patients was not found among normal controls, even when the order of testing the eyes was reversed.  相似文献   
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24.
Performance measurement of the microPET focus 120 scanner.   总被引:6,自引:0,他引:6  
The microPET Focus 120 scanner is a third-generation animal PET scanner dedicated to rodent imaging. Here, we report the results of scanner performance testing. METHODS: A (68)Ge point source was used to measure energy resolution, which was determined for each crystal and averaged. Spatial resolution was measured using a (22)Na point source with a nominal size of 0.25 mm at the system center and various off-center positions. Absolute sensitivity without attenuation was determined by extrapolating the data measured using an (18)F line source and multiple layers of absorbers. Scatter fraction and counting rate performance were measured using 2 different cylindric phantoms simulating rat and mouse bodies. Sensitivity, scatter fraction, and noise equivalent counting rate (NECR) experiments were repeated under 4 different conditions (energy window, 250 approximately 750 keV or 350 approximately 650 keV; coincidence window, 6 or 10 ns). A performance phantom with hot-rod inserts of various sizes was scanned, and several animal studies were also performed. RESULTS: Energy resolution at a 511-keV photopeak was 18.3% on average. Radial, tangential, and axial resolution of images reconstructed with the Fourier rebinning (FORE) and filtered backprojection (FBP) algorithms were 1.18 (radial), 1.13 (tangential), and 1.45 mm full width at half maximum (FWHM) (axial) at center and 2.35 (radial), 1.66 (tangential), and 2.00 mm FWHM (axial) at a radial offset of 2 cm. Absolute sensitivities at transaxial and axial centers were 7.0% (250 approximately 750 keV, 10 ns), 6.7% (250 approximately 750 keV, 6 ns), 4.0% (350 approximately 650 keV, 10 ns), and 3.8% (350 approximately 650 keV, 6 ns). Scatter fractions were 15.9% (mouse phantom) and 35.0% (rat phantom) for 250 approximately 750 keV and 6 ns. Peak NECR was 869 kcps at 3,242 kBq/mL (mouse phantom) and 228 kcps at 290 kBq/mL (rat phantom) at 250 approximately 750 keV and 6 ns. Hot-rod inserts of 1.6-mm diameter were clearly identified, and animal studies illustrated the feasibility of this system for studies of whole rodents and mid-sized animal brains. CONCLUSION: The results of this independent field test showed the improved physical characteristics of the F120 scanner over the previous microPET series systems. This system will be useful for imaging studies on small rodents and brains of larger animals.  相似文献   
25.
BACKGROUND: Acne vulgaris is an acute inflammatory disease of the pilosebaceous units. The bastion of treatment for acne vulgaris has been the use of topical and systemic therapies. Despite many modalities available for treatment, there exists an imperative need for effective noninvasive treatments that reduce the risks of medication side effects. OBJECTIVE: To study the safety and efficacy of the potassium titanyl phosphate (KTP) 532 nm pulsed laser for the treatment of acne vulgaris. METHODS: Twenty-six subjects, clinically evaluated with moderate facial acne, were enrolled in this single-center prospective trial. The entire facial area for each subject was divided in half and randomly designated as either a treatment or a control side. Each subject was treated with four laser exposures using a KTP 532 nm laser with continuous contact cooling. The results were assessed at 1 and 4 weeks post-final treatment. Primary outcome measures were Micha?lsson acne severity score and adverse treatment effects. Secondary outcome measures included subjective evaluations from the investigator and patients assessing their overall percent satisfaction. RESULTS: Primary outcome analysis in the Micha?lsson acne severity score demonstrated a mean 34.9% (p = .011) and 20.7% (p = .25) reduction at the 1-week and 4-week post-final treatments, respectively. Subjective investigator evaluations of overall percent satisfaction indicated that all patients demonstrated a minimum 50% overall satisfaction in treatment outcomes at the 4-week follow-up period. No side effects were encountered. CONCLUSION: Use of the KTP 532 nm laser for the treatment and management of acne vulgaris is both safe and effective, with positive results enduring up to 4 weeks post-treatment.  相似文献   
26.
Context Previous research on ethical issues encountered by medical professionals in training and practice have presented the thematic content of the cases they encounter rather than the activities in which clinicians engage and in which they most often encounter ethical issues. We conducted a direct observation study of paediatrics residents and their preceptors seeing patients in an out‐patient general paediatrics clinic. Our objectives were to describe the everyday ethics‐related issues paediatrics residents encounter as they interact with patients. Our ultimate goal is to use this knowledge to enhance current efforts to teach ethics to paediatrics residents. Methods The study team directly observed paediatrics residents discussing patients with their faculty preceptors (19 half‐day sessions, 76 hours) in an out‐patient general paediatrics clinic located in an urban academic medical centre. Each interaction between resident and preceptor about a single patient was considered a case for further analysis. Results A total of 247 cases were recorded. Forty‐one of the cases were coded as having ethics‐related content. A constant comparative method of qualitative data analysis revealed that residents were most likely to encounter ethical issues when engaged in the following activities: (i) maintaining a therapeutic alliance with the caregiver (e.g. the parent); (ii) prioritising patient or family needs; (iii) adjusting to the power embodied by the role of doctors, and (iv) distinguishing suboptimal care from abuse or neglect. In addition, our findings indicate that it is through their efforts to maintain the therapeutic alliance with the caregivers of their patients that residents engage in and integrate three processes: developing their medical knowledge; adhering to professional norms, and balancing the power inherent in the doctor’s role with their responsibility to serve the patient’s interests. Conclusions Medical faculty tasked with teaching ethics to paediatrics residents can utilise the results of this project to better target and enhance their ethics education efforts directed at residents in the out‐patient setting. Future research could further examine and test these findings in other clinical settings (e.g. adult general medicine).  相似文献   
27.
The sperm penetration assay is an expensive, time-consuming test to assess male fertility in vitro. Although some investigators are enthusiastic in its application, others feel that it is not sensitive or specific enough to be used as part of the routine infertility evaluation. Indeed, this bioassay is not a faithful reproduction of in vivo conditions. However, if the SPA is abnormal, it is unlikely that sperm will fertilize a human ovum in vivo. Conversely, a normal SPA does not guarantee successful in vivo fertilization. No bioassay can be absolute in its predictive value, but false-negative results must be kept to a minimum for this bioassay to be of any clinical significance. Each laboratory performing the SPA should optimize the assay for sensitivity, reproducibility, and minimization of false-negative results and then establish normal and abnormal ranges of its own. If the limitations of the SPA are kept in mind, and if we employ it very selectively, it may still be useful.  相似文献   
28.
We report a case of congenital fistula from ectopic accessory parotid gland to the cheek demonstrated by CT sialography and CT fistulography. The right parotid gland was abnormally located lateral to masseter muscle. The fistula was arising from an ectopic accessory parotid gland with ectopic duct positioned anterior to masseter muscle. CT sialography and CT fistulography were very helpful in the diagnosis and surgical planning.  相似文献   
29.
A laparoscopic approach was used for penile revascularization in a patient with vasculogenic impotence to avoid the long abdominal incision which was traditionally required to harvest the inferior epigastric artery as a neoarterial source. Despite the time-consuming nature of laparoscopy, this procedure was as efficacious but less morbid and required less convalescence than open revascularization. Whether more patients may benefit from this procedure must be evaluated in further studies.  相似文献   
30.
We performed transurethral resections of the prostate in 100 patients under local anesthesia supplemented when appropriate by intravenous medication. In the first part of the study (40 patients) local anesthesia was infiltrated into the prostate transurethrally only, while in the second part (60 patients) infiltration was performed transurethrally and perineally. Prostate sizes ranged from 5 to 50 gm., and pain control was excellent in the majority of the patients, especially when perineal infiltration was added to the procedure. Of the patients 98 per cent said they would do it again, no patient required conversion to general anesthesia and there were no significant complications relating to the anesthesia. Local anesthesia with intravenous supplementation can be performed successfully in the majority of the patients with small to moderately sized prostate glands.  相似文献   
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