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排序方式: 共有745条查询结果,搜索用时 15 毫秒
1.
ZQ Yin MD SG Crewther PhD B Pirie BSc DP Crewther PhD 《Clinical & experimental ophthalmology》1997,25(4):107-109
Purpose: It was investigated whether alterations in neuronal structure and function occasioned by strabismic amblyopia also may be reflected in alterations in the expression on Y type neurons of a Cat-301 antibody sensitive antigen in the lateral geniculate nucleus (LGN) and cortex of our cat model of strabismic amblyopia. Methods/Results: The percentage of positively labelled cells was reduced in LGN laminae that received input from the deviated eye in strabismic amblyopic cats compared with normal cats. In the strabismic cortex, the density of immunopositive neurons was significantly reduced compared with normal, the effect being most pronounced in layer IV Conclusions: Despite previous physiological recordings indicating a decrease in X-cell associated acuity in strabismic amblyopia, the present findings imply that the changes in the early visual experience occasioned by strabismus also produce specific molecular changes in theY neuronal class. 相似文献
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A comprehensive anatomic and radiographic analysis of the peribursal fat plane in 12 cadavers confirmed that the fat plane seen on radiographs represents extrasynovial fat lining the subacromial bursa and documented the anatomic relations of the bursa. A three-part retrospective clinical evaluation of rotator cuff tears, calcific tendinitis, and rheumatoid arthritis was performed. Two osteoradiologists blindly graded the appearance of the peribursal fat plane with the shoulder in external versus internal rotation in 21 patients with arthrographically intact rotator cuffs and 21 patients with disrupted rotator cuffs. The peribursal fat plane was seen better with disrupted rotator cuffs. The peribursal fat plane was seen better with the shoulder in internal rotation and was seen in 60% of control subjects but only 21% of patients with rotator cuff tears. Partial or complete obliteration of this fat plane is a sensitive (79%) but less specific (60%) indicator of rotator cuff tears. Obliteration of the peribursal fat plane by inflammatory processes in adjacent tissues, including calcific tendinitis and rheumatoid arthritis, occurred with a high frequency. 相似文献
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AJK WILLIAMS R FRASER DP CHORLEY J DENT 《Journal of gastroenterology and hepatology》1996,11(5):500-505
Safe placement of nasogastric tubes requires reliable positioning of the tip of the tube within the stomach. Radiology and aspiration are currently used to confirm tube position, but suffer from significant problems of cost and efficacy, respectively. We have developed a novel method to locate the position of a catheter tip within the body, using the detection of a low energy electromagnetic field generated in a coil located in the catheter with an external hand-held unit (Cathlocator). In vitro, the unit detected the distance of the coil from the detector with an accuracy of 0.1 cm over a range of 4–12 cm. In vivo studies were performed in 11 healthy volunteers using a purpose-built manometric assembly that incorporated the signal generating coil in its tip. In all subjects the Cathlocator showed the position of the signal generating coil to be cranial to the xiphisternum when manometric and transmucosal potential difference criteria showed it to be located above the lower oesophageal sphincter. When the coil was within the stomach, the Cathlocator identified its position within the epigastric, umbilical and left hypochondrial regions of the abdomen. The distance of the coil from the surface was significantly greater when in the duodenum mean (±s.e.m. 7.6±0.3 cm; P<0.001) and oesophagus (8.6±0.2 cm; P<0.002) than the stomach (5.0±0.4 cm). In one subject studied twice there was a close correlation between the location and depth measured by the device on each occasion. The Cathlocator is a novel non-radiological device that has the potential to be useful in the placement of gastrointestinal catheters. 相似文献
8.
The vascularity of 49 renal masses (26 malignant and 23 benign lesions) was investigated with duplex Doppler ultrasound. Doppler signals obtained at the margins of renal masses were defined as "tumor signals" when the Doppler-shifted frequency of the lesion exceeded the frequency shift in the ipsilateral main renal artery. These exceeded 2.5 kHz with a 3-MHz insonating frequency. Among the 26 renal masses that subsequently proved to be malignant, tumor signals were obtained in 15 of 18 (83%) untreated renal cell carcinomas, in three of four Wilms tumors, and in two patients with metastases to the kidney, but not in the one patient with lymphoma. None of the 23 benign renal masses demonstrated tumor signals. Tumor vascularity in malignant lesions gives rise to abnormal, high-velocity, Doppler-shifted signals that can help in the differential diagnosis of renal masses. 相似文献
9.
Frequency and species distribution of gliotoxin-producing Aspergillus isolates recovered from patients at a tertiary-care cancer center 总被引:2,自引:0,他引:2
Lewis RE Wiederhold NP Lionakis MS Prince RA Kontoyiannis DP 《Journal of clinical microbiology》2005,43(12):6120-6122
Aspergillus isolates (n = 103) collected from cancer patients were screened to determine the taxonomic distribution and quantity of gliotoxin production. Gliotoxin was detected in 93% of Aspergillus fumigatus, 75% of A. niger, 25% of A. terreus, and 4% of A. flavus cultures. Gliotoxin concentrations were highest in cultures of A. fumigatus. 相似文献
10.
G. A. Lamaris B. Esmaeli G. Chamilos A. Desai R. F. Chemaly I. I. Raad A. Safdar R. E. Lewis D. P. Kontoyiannis 《European journal of clinical microbiology & infectious diseases》2008,27(5):343-347
Few data exist on the etiology, presentation, prognosis, and management of fungal endophthalmitis (FE) in cancer patients.
FE cases were identified by reviewing the ophthalmology reports and microbiology cultures of patients at The University of
Texas M. D. Anderson Cancer Center. We retrospectively reviewed the medical records and obtained information related to malignancy,
fungal infection and its management, visual outcome, and mortality. We compared FE caused by Candida spp. (CE) to FE caused by molds (ME). Of the 102 cancer patients with a fungal infection for whom an ophthalmology consult
was requested, 23 met the criteria for definite (N = 6) or probable (N = 17) FE (8 with CE, 15 with ME). All of the patients with ME had hematologic malignancies, whereas half of the patients
with CE had solid tumor (P = .008). Only patients with CE had a history of surgery within 30 days of FE diagnosis (38%, P = .03). Fungal pneumonia [17 (74%)] and disseminated infection [14, (61%)] were common. The most common presenting symptoms
were decreased vision [16 (70%)] and ocular pain [14 (61%)]. All treated patients received systemic antifungals (combination
therapy in 72% of the cases). Seven patients (30%) underwent vitrectomy. Only one patient received intraocular injection of
amphotericin B along with systemic antifungals. Four-week mortality was high [13 (57%)], especially in ME (73%, P = .04). Among the eight surviving patients where visual acuity could be assessed, visual outcome improved or remained stable
in five (63%). FE in cancer patients occurs in the setting of severe, frequently disseminated opportunistic mycoses, is caused
predominantly by hyalohyphomycetes, and is a marker for high 4-week mortality. 相似文献