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排序方式: 共有239条查询结果,搜索用时 15 毫秒
91.
Flowing cerebrospinal fluid in normal and hydrocephalic states: appearance on MR images 总被引:3,自引:0,他引:3
The signal intensity of the cerebrospinal fluid (CSF) in the cerebral aqueduct and lateral ventricles on magnetic resonance (MR) images was evaluated in 16 healthy individuals and in 32 patients with various forms of hydrocephalus (20 with chronic normal pressure hydrocephalus [NPH], seven with acute communicating hydrocephalus, and five with hydrocephalus ex vacuo [atrophy]). The low signal intensity frequently observed in the cerebral aqueduct is believed to reflect the pulsatile motion of CSF, which is related to the cardiac cycle. While this "aqueductal flow void phenomenon" can be observed in healthy individuals, it is most pronounced in patients with chronic, communicating NPH; is less evident in patients with acute, communicating hydrocephalus; and is least evident in patients with atrophy. Ventricular compliance is known to be essentially normal in atrophy; mildly decreased in acute, communicating hydrocephalus; and severely decreased in NPH. The degree of aqueductal signal loss is believed to reflect the velocity of the pulsatile CSF motion, which in turn depends on the relative ventricular compliance and surface area. 相似文献
92.
US of the biceps tendon apparatus 总被引:1,自引:0,他引:1
High-resolution real-time sonography of the biceps tendon was performed on 80 patients referred for shoulder arthrography. The arthrograms and sonograms were compared at the levels of the biceps tendon groove and distal tendon. Sonography and arthrography were equally successful in facilitating the evaluation of the bony configuration of the biceps tendon groove, but sonography gave a superior image of the biceps tendon within the groove. In 16 patients, biceps tendon sheath effusions or swelling was detected using sonography; 15 of these patients had associated pathologic conditions elsewhere in the joint. Arthrograms did not disclose a biceps tendon or sheath abnormality in any of these patients. We conclude that sonography could be the imaging method of choice in patients with suspected biceps tendon lesions and that the presence of a biceps tendon or sheath abnormality indicates an increased likelihood of abnormalities elsewhere in the joint. 相似文献
93.
Supratentorial ependymoma: CT appearance 总被引:5,自引:0,他引:5
Armington WG; Osborn AG; Cubberley DA; Harnsberger HR; Boyer R; Naidich TP; Sherry RG 《Radiology》1985,157(2):367-372
The computed tomographic appearances of 22 biopsy-proved supratentorial ependymomas were analyzed. Supratentorial ependymomas were usually intraparenchymal, larger than 4 cm, and cystic. Contrast enhancement was moderate to intense, with homogeneous or ring-enhancement patterns commonly seen. Intratumoral calcification was present in one-third of the cases, while hydrocephalus and peritumoral edema were seen in 50%. Intratumoral hemorrhage was not a characteristic of the lesion. In contrast to cellular ependymomas, malignant ependymomas and ependymoblastomas demonstrate higher attenuation prior to administration of contrast material, more intense enhancement, lower frequency of calcification within the tumor, and less distinct margination. 相似文献
94.
95.
丹皮酚抗大鼠心肌缺血再灌注损伤与抗膜脂质过氧化作用 总被引:11,自引:0,他引:11
丹皮酚抗大鼠心肌缺血再灌注损伤与抗膜脂质过氧化作用张卫国,张志善(武汉湖北医科大学药理教研室430071)丹皮酚是非甾体类解热镇痛药,有抗动脉粥样硬化斑块形成、抑制血小板聚集(1),及抗心律失常和降压作用(2),并对钙反常培养乳鼠心肌细胞Ca2+内流... 相似文献
96.
Retrospective analysis showed that 67 children had presented in Edinburgh with needlestick injuries on 70 occasions over five years. Worryingly, 10 children sustained injuries pretending to be intravenous drug abusers. Despite risks of hepatitis B and HIV infection, protection and follow up were inadequate. Publicity about discarded needles and a treatment plan for use in accident and emergency departments are recommended. 相似文献
97.
OBJECTIVE: Trypsin-like protease (TLPase) enzyme produced by Porphyromonas gingivalis has been implicated as a virulence factor in the pathogenesis of periodontal disease. The aims of this study were to investigate the relationship between cultivable P. gingivalis , TLPase enzyme activity (BANA hydrolysis) and serum antibody levels against cell sonicate and a purified TLPase antigen from P. gingivalis W50.
MATERIALS AND METHODS: Sub-gingival plaque samples were cultured for levels of P. gingivalis together with a chairside analysis of TLPase enzyme activity (Perioscan) from periodontitis and gingivitis sites of adult periodontitis patients. A TLPase from P. gingivalis was purified by gel filtration and ion exchange chromatogra-phy from the vesicle fraction for use as a test antigen. RESULTS: Elevated levels of P. gingivalis were found at periodontitis sites, however, there was no correlation with sub-gingival plaque TLPase enzyme activity. Adult periodontitis patients had higher levels of IgG and IgA against cell sonicate and TLPase antigens than did controls. Those patients who were P. gingivalis culture-positive demonstrated an elevated immune response against both cell sonicate and TLPase when compared to P. gingivalis culture-negative patients. Treatment resulted in an improvement of clinical indices and no cultivable P. gingivalis could be recovered from the treated sites and there was a concomitant decrease in IgG levels against the TLPase. There was no significant difference in BANA hydrolysis at gingivitis sites or periodontitis sites after treatment.
CONCLUSIONS Further longitudinal studies are suggested to investigate the role of the TLPase in the response to treatment of chronic adult periodontitis patients. 相似文献
MATERIALS AND METHODS: Sub-gingival plaque samples were cultured for levels of P. gingivalis together with a chairside analysis of TLPase enzyme activity (Perioscan) from periodontitis and gingivitis sites of adult periodontitis patients. A TLPase from P. gingivalis was purified by gel filtration and ion exchange chromatogra-phy from the vesicle fraction for use as a test antigen. RESULTS: Elevated levels of P. gingivalis were found at periodontitis sites, however, there was no correlation with sub-gingival plaque TLPase enzyme activity. Adult periodontitis patients had higher levels of IgG and IgA against cell sonicate and TLPase antigens than did controls. Those patients who were P. gingivalis culture-positive demonstrated an elevated immune response against both cell sonicate and TLPase when compared to P. gingivalis culture-negative patients. Treatment resulted in an improvement of clinical indices and no cultivable P. gingivalis could be recovered from the treated sites and there was a concomitant decrease in IgG levels against the TLPase. There was no significant difference in BANA hydrolysis at gingivitis sites or periodontitis sites after treatment.
CONCLUSIONS Further longitudinal studies are suggested to investigate the role of the TLPase in the response to treatment of chronic adult periodontitis patients. 相似文献
98.
Tegtmeyer CJ; Kellum CD; Jenkins A; Gillenwater JY; Way WG; Barr J; Piros G; Springer R; Lippert MC; Wyker AW 《Radiology》1986,161(3):587-592
Among 1,500 patients treated with extracorporeal shock wave lithotripsy, 1,300 had calculi less than 2.5 cm in diameter and 200 had calculi of 2.5 cm or larger. Although most patients did well and required no further radiologic intervention, 178 interventional radiologic procedures were performed. Urinary tract obstruction often developed in patients with large stones when the collecting system filled with stone fragments (steinstrasse). Nephrostomy was performed in 5.3% of the total patient population and in 29% of the patients with stones measuring 2.5 cm or more. Only 1.8% of the patients with calculi smaller than 2.5 cm required radiologic intervention. When the obstructed collecting system could not be crossed with conventional angiographic techniques, the stone fragments were removed through a percutaneous nephrostomy tract either by flushing or by suctioning with a pulsating water jet. 相似文献
99.
Retrospective analysis of 139 ventilation-perfusion (V/Q) lung scans obtained for suspected pulmonary embolism (PE) was undertaken, using the Biello criteria for interpretation. All scans were correlated with chest radiographs obtained within 24 hours and with pulmonary angiograms obtained within 72 hours of the V/Q study. The prevalence of PE in the high-, intermediate-, and low-probability groups was 89.5%, 49.3%, and 3.6%, respectively. Using minor modifications of these criteria, V/Q scans interpreted as high or low probability had a sensitivity of 97.1%, specificity of 94.3%, and accuracy of 95.7%. Perfusion defects corresponding to radiographic abnormalities that were present for at least 10 days were less likely to be associated with PE. Separate analysis of 27 perfusion-only lung scans that met all other criteria for inclusion in the study confirmed the nonspecificity of perfusion-only lung imaging and indicated the need for ventilation imaging with Tc-99m-DTPA aerosol or Kr-81m gas for portable studies. 相似文献
100.
Sonographic evaluation of normal and induced ovulation 总被引:1,自引:0,他引:1
The adult premenopausal ovary exists in a dynamic state of flux, with ovarian position, size, activity, and structure constantly undergoing changes. Pelvic sonograms must be interpreted with knowledge of the stage of the menstrual cycle and the expected normal range of sonographic findings, because features that are normal in one phase may be abnormal in another. Only against this background knowledge can the challenging task of interpretation of pelvic sonograms be successfully performed. US also plays an increasingly important role in monitoring ovulation induction and alternative methods of fertilization and has improved pregnancy rates by distinguishing between the presence of one or more mature follicles as opposed to a cohort of immature follicles, suggesting the possibility of multiple ovulation with the risks of hyperstimulation or poor pregnancy outcome from multiple gestation, indicating optimum timing of human chorionic gonadotropin administration, allowing detection and confirmation of normal follicular rupture and ovulation, indicating optimum timing of oocyte retrieval in programs of in vitro fertilization with embryo transfer (IVF-ET) or insemination programs, and assessing pathologic pelvic conditions and ovarian accessibility in IVF-ET programs. Oocyte retrieval and embryo transfer are also being performed under US guidance. 相似文献