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61.
Abstract Purpose: To report the clinical course of a highly myopic woman treated by a single intravitreal injection of bevacizumab during the first trimester of pregnancy. Methods: Observational case report. A 35-year-old woman affected by pathologic myopia complained of blurred vision in her left eye in the fourth week of pregnancy. A subfoveal myopic choroidal neovascularization (CNV) was diagnosed on the basis of slit-lamp fundus biomicroscopy and fluorescein angiography. After discussing the treatment-related risks, she was administered an intravitreal injection of bevacizumab in her seventh gestational week. During pregnancy, fetal ultrasound and ophthalmic examination were performed monthly. After delivery, the mother and infant were followed quarterly for 12 months. Results: The patient had an uneventful prenatal course and delivered a healthy full-term infant. Significant visual improvement with no documented adverse events related to treatment was obtained. Conclusions: In our experience, a single intravitreal bevacizumab injection administered during the first trimester of pregnancy did not provoke any complications, and was effective in myopic CNV treatment. Further studies are warranted to provide more detailed information about this treatment and the related risks in pregnant women.  相似文献   
62.

Purpose

To evaluate changes in macular morphology due to myopic choroidal neovascularization (CNV), using spectral-domain optical coherence tomography (SD-OCT).

Methods

In all, 22 eyes with recent-onset untreated CNV underwent 1 intravitreal injection of anti-vascular endothelial growth factor (anti-VEGF), followed by a pro-re-nata regimen. SD-OCT was performed at baseline (before first administration of anti-VEGF treatment) and month 1, and 2; macular morphologic changes and outer retina characteristics (SD-OCT findings) associated with CNV activity were evaluated. Sensitivity and specificity were calculated for SD-OCT findings using fluorescein angiography (FA) as standard reference.

Results

Mean central retinal thickness (CRT) showed no significant reduction from baseline (284±98 μm) to month 1 (257±74 μm) and month 2 (263±72 μm). A hyper-reflective lesion with fuzzy borders (fuzzy area), and ‘absent or altered'' IS/OS junction were the only SD-OCT findings associated with CNV activity (P<0.0001). Both these SD-OCT findings showed good sensitivity and specificity (95.1 and 96.0% (95% CI: 0.87–0.89), respectively, for the fuzzy area; 87.9 and 66.7% (95% CI: 0.65–0.87), respectively, for ‘absent or altered'' IS/OS junction) when compared with FA leakage (standard reference).

Conclusions

Outer retina characteristics (ie, hyper-reflective lesion with fuzzy borders, and ‘absent or altered'' IS/OS junction) appear more meaningful than CRT in the evaluation of myopic CNV activity. These SD-OCT findings show overall good sensitivity and specificity when compared with FA leakage (standard reference), and could be considered as an alternative diagnostic tool to FA for myopic CNV monitoring.  相似文献   
63.
Role of the B domain for factor VIII and factor V expression and function   总被引:4,自引:3,他引:4  
Pittman  DD; Marquette  KA; Kaufman  RJ 《Blood》1994,84(12):4214-4225
Factor V and factor VIII are homologous cofactors in the blood coagulation cascade that have the domain structure A1-A2-B-A3-C1-C2, of which the B domain has extensively diverged. In transfected COS-1 monkey cells, expression of factor VIII is approximately 10-fold less efficient than that of factor V, primarily because of inefficient protein secretion and, to a lesser extent, reduced mRNA expression. To study the functional significance and effect of the B domain on expression and activity, chimeric cDNAs were constructed in which the B domains of factor V and factor VIII were exchanged. Expression of a factor VIII chimera harboring the B-domain of factor V yielded a fully functional factor VIII molecule that was expressed twofold more efficiently than wild-type factor VIII because of increased mRNA expression. Thus, sequences within the factor VIII B domain were not responsible for the inefficient secretion of factor VIII compared with factor V. Expression of a factor V chimera harboring the B domain of factor VIII was slightly reduced compared with wild-type factor V, although the secreted molecule had significantly reduced procoagulant activity correlating with dissociated heavy and light chains and resistance to thrombin activation. Interestingly, the factor V chimera containing the factor VIII B domain was efficiently activated by Russell's viper venum (RVV). A factor V B domain deletion (residues 710- 1545) molecule also exhibited significantly reduced procoagulant activity caused by resistance to thrombin cleavage and activation, although this molecule was activatable by RVV. These results show that, in contrast to factor VIII, thrombin activation of factor V requires sequences within the B domain. In addition, thrombin activation of factor V occurs through a different mechanism than activation by RVV.  相似文献   
64.
Chemoprophylaxis against HIV after accidental blood exposures represents a new indication for antiretroviral drugs. Efficacy has been suggested by the results of a case-control study in health care workers and the reduction of mother to infant transmission of HIV with zidovudine. The post-exposure treatment should be given as soon as possible, and in the latest at 48 hours. National guidelines recommend a triple therapy with or without protease inhibitor, adapted to the source patient. The evaluation of efficacy needs a standardized follow-up.  相似文献   
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68.

Purpose

To determine whether asymmetric spermatic cord vessel enhancement (ASE) on contrast-enhanced computed tomography (CECT) indicates scrotal pathology.

Methods

Sixty-one male patients with scrotal symptoms who underwent both scrotal ultrasound (US) and CECT within 24 h were identified through a radiology information system. Twenty-eight emergency department patients who underwent CECT only for unrelated symptoms were included for comparison. Two blinded radiologists independently reviewed each CECT scan for qualitative ASE. These data were compared with US diagnoses, when present. A third blinded radiologist reviewed each CECT scan for quantitative ASE by measuring Hounsfield unit (HU) density ratios. McNemar, Kappa, Student’s t test, and ANOVA were used for analysis.

Results

Eighty-nine total patients included 28 with CECT only and 61 with CECT and US, of which 41 had abnormal US: 15 acute epididymitis and/or orchitis, 7 testicular neoplasms, 11 varicoceles, and 8 with other pathologies. Twenty patients with normal US and 28 patients with CECT only served as control groups. Identification of ASE agreed with US diagnosis of epididymitis (and/or orchitis) or testicular neoplasm (reader 1: κ = 0.79, reader 2: κ = 0.75) with average 95.5% sensitivity and 88.8% specificity, and no significant difference between readers (p = 0.58). For epididymitis (and/or orchitis) or testicular neoplasm patients, the average ratio of spermatic cord HU density (ipsilateral:contralateral) was significantly different from other patients (4.01 vs. 1.26, p = 0.0025).

Conclusion

ASE on CECT shows stronger correlation with epididymitis (and/or orchitis) and testicular neoplasm compared with other scrotal pathologies. If discovered on CECT, this should prompt further clinical and/or imaging workup.  相似文献   
69.
Duodenal hematoma: the ring sign in MR imaging   总被引:1,自引:1,他引:0  
Hahn  PF; Stark  DD; Vici  LG; Ferrucci  JT  Jr 《Radiology》1986,159(2):379-382
Proper management of duodenal hematoma requires that an accurate diagnosis be made using noninvasive radiological methods. Conventional imaging may be nonspecific if there is no history of trauma or coagulopathy. Two cases of duodenal hematoma that were imaged by magnetic resonance (MR) and computed tomography (CT) are described. In both cases the hematoma had a well-defined concentric ring configuration on MR images, a finding which helped establish the diagnosis. MR imaging may provide tissue-specific characterization of duodenal hematomas.  相似文献   
70.
Diverse materials with varying physical and magnetic properties have been evaluated as gastrointestinal contrast agents for magnetic resonance (MR) imaging. Uniform marking of the small bowel remains the greatest challenge. Ferrites are magnetically active iron oxide particles that are miscible with water and cause loss of signal on MR images. The decrease in MR signal intensity produced by ferrites occurs with a wide range of iron concentrations (0.1-10 mM) and with both T1- and T2-weighted pulse sequences. These effects of ferrites are explained by predominant T2 shortening with negligible T1 effects. The ferrite preparation used in this study was stable in vitro, with little iron solubilized by acid. Intragastric administration of ferrite (5 mg of iron per kg in 6 ml) routinely marked the small bowel of rats. The authors conclude that ferrites represent a promising new class of contrast agents for gastrointestinal MR imaging.  相似文献   
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