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41.
骨关节放大摄影的临床应用和诊断价值   总被引:1,自引:0,他引:1  
目的 :评价和比较X线放大像与普通X线平片诊断价值。方法 :对 386例患者 (男 2 6 7例 ,女 119例 )。患处原有普通X线平片部位进行X线放大摄影 ,并与原片进行对比分析。结果 :放大像发现病变阳性率为 75 .91%(2 93/ 386 ) ,普通X线平片发现病变阳性率为 5 7.5 1% (2 2 2 / 386 ) ,两者比较 ,前者的阳性率明显高于后者。结论 :对普通X线平片不能作出确切诊断的病例 ,摄X线放大像可提高诊断准确性 ,且有重要诊断价值  相似文献   
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High-frequency ultrasound (US) is an efficient, rapid and inexpensive altenative to magnetic resonance imaging (MRI) for investigation of diseases in the soft tissues of the wrist and hand. US allows detection of foreign bodies and the reliable identification of a variety of traumatic lesions affecting tendons, annular pulleys, ligaments, vessels and nerves. Inflammatory diseases of tendons, including acute and chronic tenosynovitis and some degenerative conditions in the wrist and hand, can also be diagnosed. In entrapment neuropathies, US is able to identify nerve shape changes and possible extrinsic space-occupying lesions that may cause nerve compression within the tunnels. In patients with localized swelling of the hand or wrist, US is able to assess the presence of an expansile lesion and to characterize its nature in most cases. The objective of this article is to review the main findings and the primary indications of US in the investigation of disorders of the hand and wrist. Received: 10 September 1998 Accepted: 24 November 1998  相似文献   
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目的研究骨巨细胞瘤组织中CD105和MMP-9的表达及与肿瘤生物学行为的关系。方法运用免疫组织化学S-P法,检测CD105和MMP-9在38例骨巨细胞瘤中的表达,分析其与肿瘤临床病理特征及复发的关系。结果1)CD105标记的肿瘤内MVD值为(9.70±2.34),MVD值随肿瘤组织学级别的升高而递增,但差异无显著性(P>0.05)。按X线表现分型,浸润型肿瘤的MVD值明显高于静止型,差异有显著性(P<0.05)。复发组的骨巨细胞瘤其MVD值高于未复发组,差异有显著性(P<0.01)。肿瘤内MVD值与放射学分型、肿瘤复发有关。2)MMP-9在骨巨细胞瘤中的阳性表达率为60.53%,MMP-9阳性表达率在不同组织学分级的病例中差异无显著性(P>0.05),按X线表现分型,MMP-9在活动型、浸润性两组的阳性率高于静止型组,差异有显著性(P<0.01)。MMP-9在复发组的表达率高于未复发组,差异有显著性(P<0.01),提示MMP-9过表达与肿瘤的复发有关。3)MMP-9阳性组的MVD值高于MMP-9阴性组,差异有显著性(P<0.01),Spearman相关分析提示MMP-9表达与MVD值呈正相关。结论CD105标记的MVD值和MMP-9过表达可作为预测骨巨细胞瘤复发的客观依据。MMP-9过表达与骨巨细胞瘤内新生血管的形成有关。  相似文献   
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《Clinical neurophysiology》2021,132(3):708-719
ObjectiveTo clarify the effects of unfused cranial bones on magnetoencephalography (MEG) signals during early development.MethodsIn a simulation study, we compared the MEG signals over a spherical head model with a circular hole mimicking the anterior fontanel to those over the same head model without the fontanel for different head and fontanel sizes with varying skull thickness and conductivity.ResultsThe fontanel had small effects according to three indices. The sum of differences in signal over a sensor array due to a fontanel, for example, was < 6% of the sum without the fontanel. However, the fontanel effects were extensive for dipole sources deep in the brain or outside the fontanel for larger fontanels. The effects were comparable in magnitude for tangential and radial sources. Skull thickness significantly increased the effect, while skull conductivity had minor effects.ConclusionMEG signal is weakly affected by a fontanel. However, the effects can be extensive and significant for radial sources, thicker skull and large fontanels. The fontanel effects can be intuitively explained by the concept of secondary sources at the fontanel wall.SignificanceThe minor influence of unfused cranial bones simplifies MEG analysis, but it should be considered for quantitative analysis.  相似文献   
46.
The objective of the present study was to determine whether it is possible to consistently and reliably teach medical students and resident learners how to administer local anesthetics in an almost painless manner. Using the published technique, 25 consecutive medical students and residents were taught how to inject local anesthetics for carpal tunnel release by watching the senior author perform the technique once. The learner then independently administered the anesthesia to the next patient who then scored the learner’s ability to inject the local anesthetic from a pain perspective. The teaching technique is demonstrated in an accompanying online video. The learners were consistently capable of administering local anesthetics with minimal pain. During the injection process, the patients only felt pain once (‘hole-in-one’) 76% of the time. This pain was attributed to the first 27-gauge needle poke. The other 24% of the time, patients felt pain twice (eagle) during the 5 min injection process. All 25 patients rated the entire pain experience to be less than 2/10. Eighty-four per cent of the patients indicated that the experience was better than local anesthetic given at the dentist’s office. Medical students and residents can quickly and reliably learn how to administer local anesthesia for carpal tunnel release with minimal pain to the patient.  相似文献   
47.
《Acta oto-laryngologica》2012,132(5):583-587
Objective --Persistent embryonic connective tissue has been considered to be a cause of chronic otitis media with effusion in neonates and of cholesteatoma in later life. As part of a study of pneumatization and resorption of embryonic connective tissue from the middle ear of pre- and postnatal infants, inflammatory processes of variable extents have been observed within the embryonic connective tissue. The aim of the present study was to characterize this inflammation and to detect patterns in its presence and distribution. Material and Methods --Twenty fetal temporal bones obtained at 4-8 months of development and 31 temporal bones from children who died of sudden infant death syndrome aged < 1 year were studied to assess the inflammation within the middle ear cleft and specifically in the embryonic connective tissue. Results --Sixteen of 27 (59.3%) pre- and 10/31 (32.2%) postnatal specimens displayed a non-specific inflammatory lymphocytic infiltration without signs of bacterial infection or the presence of or reaction to amniotic contents. Eleven of 27 prenatal temporal bones (40.7%) and 16/31 (51.6%) postnatal specimens showed no evidence of histologic middle ear inflammation. The presence or absence of inflammation was independent of age. Conclusion --Our observations indicate resorption of the embryonic connective tissue with individual variations indicating that genetic factors are responsible for the development of the middle ear spaces during the phases of development studied.  相似文献   
48.
Carpal tunnel syndrome (CTS) is known to develop post-stroke. Median nerve ultrasound (US) is an inexpensive, effective means of screening. In this prospective feasibility study, we compared the ability of the physical exam, the Boston Carpal Tunnel Questionnaire (BCTQ) and median nerve US to screen for carpal tunnel syndrome (CTS) within 72 hours of stroke onset. We enrolled 24 consecutive patients. Using US, 19 (79%, p = 0.0386) of the 24 patients screened positive for CTS on the paretic side and 20 (83%, p = 0.0042) on the nonparetic side. With clinical examination, only 11 out of 24 (46%) screened positive for CTS on the paretic side and 8 (33%) on the nonparetic side. The BCTQ did not predict CTS. US can be an effective screening tool post-stroke. Further research is needed to determine specificity and efficacy compared to electrodiagnostic testing in this population.  相似文献   
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