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991.
992.
Saline-infused sonohysterography (SIS) may help improve visualization of the endometrium and endometrial cavity and assess tubal patency. Although most SIS procedures are straightforward, a variety of pitfalls may lead to an unsuccessful procedure or incomplete evaluation. SIS should be scheduled between days 4 and 10 of the patient's menstrual cycle, when the endometrium is at its thinnest, and physiologic changes during the secretory phase are not present. Performing preprocedure imaging serves many purposes, such as depicting hydrosalpinx, causes of uterine and adnexal tenderness, and pelvic inflammatory disease, as well as assessing the size and position of the uterus and the orientation of the cervix. It is important not to presume that fibroids are the cause of bleeding when the endometrium is obscured at preprocedure imaging. Obstacles to a successful procedure include issues related to patient anxiety and discomfort, which may be prevented or minimized at almost every step of the procedure. Inability to obtain access to the cervix is the most common cause of unsuccessful SIS; proper patient positioning in a semi-upright lithotomy position is important. Injection of air during any US-guided procedure may lead to shadowing that obscures the region of interest. Adequate distention of the endometrial cavity is crucial for successful SIS, and optimal positioning of the distended balloon may improve the degree of distention. However, poor distention may be indicative of an underlying pathologic condition. Knowledge of these pitfalls and the strategies to overcome them may prevent premature or unnecessary termination of an otherwise successful study.  相似文献   
993.
In this study, a method for whole‐body diffusion‐weighted imaging (wbDWI) during continuous table motion has been developed and implemented on a clinical scanner based on a short‐Tau inversion recovery echo‐planar DWI sequence. Unlike currently available multistation wbDWI, which has disadvantages such as long scanning times, poor image quality, and troublesome data realignment, continuously moving table wbDWI can overcome these technical problems while extending the longitudinal field of view in MRI systems. In continuously moving table wbDWI, images are acquired consecutively at the isocenter of the magnet, having less geometric distortions and various possibilities of spatial and temporal coverage of an extended field of view. The acquired images, together with an apparent diffusion coefficient analysis, show that continuously moving table wbDWI can be used by appropriately adapting the table velocity, scan range, radiofrequency coils, slice resolutions, and spatio‐temporal acquisition schemes according to various clinical demands. Magn Reson Med, 2011. © 2011 Wiley‐Liss, Inc.  相似文献   
994.

Purpose

To examine the extent to which an ACL injury prevention programme modifies lower extremity biomechanics during single- and double-leg landing tasks in both the sagittal and frontal plane. It was hypothesized that the training programme would elicit improvements in lower extremity biomechanics, but that these improvements would be greater during a double-leg sagittal plane landing task than tasks performed on a single leg or in the frontal plane.

Methods

Ninety-seven competitive multi-directional sport athletes that competed at the middle- or high-school level were cluster randomized into intervention (n?=?48, age?=?15.4?±?1.0 years, height?=?1.7?±?0.07 m, mass?=?59.9?±?11.0 kg) and control (n?=?49, age?=?15.7?±?1.6 years, height?=?1.7?±?0.06 m, mass?=?60.4?±?7.7 kg) groups. The intervention group participated in an established 6-week warm-up-based ACL injury prevention programme. Three-dimensional biomechanical analyses of a double- (SAG-DL) and single-leg (SAG-SL) sagittal, and double- (FRONT-DL) and single-leg (FRONT-SL) frontal plane jump landing tasks were tested before and after the intervention. Peak angles, excursions, and external joint moments were analysed for group differences using 2 (group)?×?4 (task) repeated measures MANOVA models of delta scores (post–pre-test value) (α?<?0.05).

Results

Relative to the control group, no significant biomechanical changes were identified in the intervention group for any of the tasks (n.s.). However, a group by task interaction was identified for knee abduction (λ?=?0.80, p?=?0.02), such that participants in the intervention group showed relative decreases in knee abduction moments during the SAG-DL compared to the SAG-SL (p?=?0.005; d?=?0.45, CI?=?0.04–0.85) task.

Conclusion

A 6-week warm-up-based ACL injury prevention programme resulted in no significant biomechanical changes during a variety of multi-directional jump landings. Clinically, future prevention programmes should provide a greater training stimulus (intensity, volume), more specificity to tasks associated with the mechanism of ACL injury (single-leg, non-sagittal plane jump landings), and longer programme duration (>?6 weeks) to elicit meaningful biomechanical changes.

Level of evidence

I.
  相似文献   
995.
Spatial and temporal gait parameters in 40 patients with early Alzheimer's disease (AD) were compared to that of 34 normal controls (NC) on a level ground and on a treadmill. Over-ground velocity, cycle-time, cadence, stride-length, stride-width and double-support time were captured on an electronic walkway. On the treadmill, cadence, cycle-time and double-support time were recorded at a preferred velocity using footswitches. The AD group were significantly slower on the Timed Up and Go task compared to NC (p < 0.05). AD patients differed significantly from the NC on their over-ground gait velocity (99 ± 19 cm/s vs 119 + 15 cm/s, p < 0.001), cadence (101 ± 9 steps/min vs 109 ± 9 steps/min, p = 0.001) and stride-length (118 ± 18 cm vs 131 ± 17 cm, p < 0.01). On the treadmill, only preferred speed was significantly different in the AD group compared to the NC group (60 ± 20 cm/s vs 74 ± 23 cm/s, p = 0.02). These results indicate that patients with early AD walk slower and with shorter strides than healthy older adults.  相似文献   
996.

Aim

Distant metastasis has a negative impact on survival in differentiated thyroid carcinoma (DTC). The timing of this manifestation, however, is of unknown prognostic relevance. The aim of this retrospective study was to investigate the potential significance of discriminating synchronous versus metachronous distant metastases (SDM vs. MDM) for the outcome of patients with DTC.

Methods

We retrospectively analyzed a consecutive cohort of n?=?89 patients with distant metastases of DTC (43 with follicular, 46 with papillary DTC histology; mean age 52.6?±?17.7 years) undergoing radioiodine treatment at our institution. All patients were treated with the same protocol consisting of ablative radioiodine therapy (RIT, 3.7 GBq) and one post-ablation treatment after 3 months (3.7–11.1 GBq). Further cycles of RIT were administered for recurrent, progressive or newly developed metastatic disease. We distinguished 2 types of distant metastases according to the time of manifestation: SDM (within ≤12 months after DTC diagnosis) and MDM (occurring >12 months after diagnosis). Tumor-related survival was analyzed using the Kaplan–Meier method. Uni- and multivariate analyses including the Cox proportional hazards model were performed with a significance level of p?<?0.05.

Results

The mean follow-up period was 13.8?±?1.2 years. SDM were present in 49 (55.1 %), MDM in 40 (44.9 %) patients. MDM were associated with shorter tumor-related survival (p?=?0.002). 5-year and 10-year survival rates were 68.5 % and 34.8 % for MDM, and 84.3 % and 66.9 % for SDM, respectively. Within both age subgroups of <45 and ≥45 years, SDM were also linked with longer survival. No effect on tumor-related survival was found for the co-variables sex, lymph node metastases and histologic type.

Conclusion

Distinguishing synchronous from metachronous manifestation of distant metastases may add an important prognostic feature to risk stratification in DTC, as proven metachronous appearance is associated with impaired survival.
  相似文献   
997.
ObjectiveThe aim of this systematic review and meta-analysis was to study the association between specific environmental risk factors (ERF) and later development of Bipolar disorder and Psychotic depression.MethodsA systematic search of prospective studies was conducted in MEDLINE, EMBASE and PsycINFO databases, and supplemented by hand searching, according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines (registration number: CRD42018092253). Selected ERF included: pre-/peri-natal factors—paternal age at birth, maternal infection, obstetric complications, perinatal stress; early childhood factors—urbanicity at birth, childhood infection, childhood adversity; later life factors—substance misuse, ethnic minority and migration, urbanicity later in life, stressful life events, and traumatic head injury. Pooled effect sizes of the association between these ERF and affective psychoses were calculated from systematically selected studies. When studies examining each ERF were insufficient for meta-analysis, results were presented narratively.ResultsForty-six studies were included for quantitative analyses among selected ERF for affective psychosis, with significant association found for paternal age >40 years (OR 1.17, 95%CI 1.12–1.23), early (OR 1.52, 95%CI 1.07–2.17) and late (OR 1.32, 95%CI 1.05–1.67) gestational age, childhood adversity (OR 1.33, 95%CI 1.18–1.50), substance misuse (OR 2.87, 95%CI 1.63–5.50), and being from an ethnic minority (OR 1.99, 95%CI 1.39–2.84).ConclusionsThese results suggest some shared environmental load between non-affective and affective psychosis, implying generalized risks for psychosis rather than for specific diagnostic categories. Nonetheless, published studies for some ERF in the affective psychoses are scarce, and further longitudinal studies are needed.  相似文献   
998.
White matter hyperintensities (WMHs) are associated with vascular risk and Alzheimer’s disease. In this study, we examined relations between WMH load and distribution, amyloid pathology and vascular risk in 339 controls and cases with either subjective (SCD) or mild cognitive impairment (MCI). Regional deep (DWMH) and periventricular (PWMH) WMH loads were determined using an automated algorithm. We stratified on Aβ1-42 pathology (Aβ+/−) and analyzed group differences, as well as associations with Framingham Risk Score for cardiovascular disease (FRS-CVD) and age. Occipital PWMH (p = 0.001) and occipital DWMH (p = 0.003) loads were increased in SCD-Aβ+ compared with Aβ− controls. In MCI-Aβ+ compared with Aβ− controls, there were differences in global WMH (p = 0.003), as well as occipital DWMH (p = 0.001) and temporal DWMH (p = 0.002) loads. FRS-CVD was associated with frontal PWMHs (p = 0.003) and frontal DWMHs (p = 0.005), after adjusting for age. There were associations between global and all regional WMH loads and age. In summary, posterior WMH loads were increased in SCD-Aβ+ and MCI-Aβ+ cases, whereas frontal WMHs were associated with vascular risk. The differences in WMH topography support the use of regional WMH load as an early-stage marker of etiology.  相似文献   
999.
Background and purposeTo determine the diagnostic value of bright spotty lesions (BSLs) for aquaporin-4 antibody-positive neuromyelitis optica spectrum disorder (NMOSDAQP4+), the predictive value of axial-BSLs for AQP4-IgG seropositivity, and the radio-clinical differences in NMOSDAQP4+ patients with and without axial-BSLs.Materials and methodsRetrospective study that included patients aged  16 years, with a first acute spinal cord syndrome between 2005 and 2018 and abnormal spinal cord MRI with axial and sagittal T2 sequences. Patients with MRI findings consistent with compressive myelopathy were excluded. All spinal cord MRI were retrospectively evaluated for the presence of BSLs by 2 radiologists blinded to the diagnosis of acute myelopathy.ResultsA total of 82 patients were included; 15 aquaporin-4 antibody-positive neuromyelitis optica spectrum disorder patients (NMOSDAQP4+), and 67 other patients, considered as the other causes of myelopathy (OM) group. The specificity of axial-BSLs for NMOSDAQP4+ patients was 94.0% (95% CI [85.6 to 97.7]). The sensitivity was 40.0% (95% CI [19.8 to 64.3]). In the multivariable analysis, the only MRI characteristic associated with AQP4-IgG positivity was the presence of axial-BSLs (OR: 9.2, 95% CI [1.2 to 72.9]; P = 0.022). In NMOSDAQP4+ patients, the median of cord expansion ratio was higher with axial-BSL (1.2, IQR [1.1–1.3]) than without axial-BSL (1.1, IQR [1.0–1.2]; P = 0.046).ConclusionAfter a first acute spinal cord syndrome, the presence of axial-BSLs on spinal cord MRI seems very specific for NMOSDAQP4+ and seems to be a predictor radiological marker of AQP4-IgG positivity.  相似文献   
1000.
The putative protein tyrosine kinase (PTK) inhibitor tyrphostin AG126 has proven beneficial in various models of inflammatory disease. Yet molecular targets and cellular mechanisms remained enigmatic. We demonstrate here that AG126 treatment has beneficial effects in experimental autoimmune encephalomyelitis (EAE), a model for multiple sclerosis. AG126 alleviates the clinical symptoms, diminishes encephalitogenic Th17 differentiation, reduces inflammatory CNS infiltration as well as microglia activation and attenuates myelin damage. We show that AG126 directly inhibits Bruton's tyrosine kinase (BTK), a PTK associated with B cell receptor and Toll‐like receptor (TLR) signaling. However, BTK inhibition cannot account for the entire activity spectrum. Effects on TLR‐induced proinflammatory cytokine expression in microglia involve AG126 hydrolysis and conversion of its dinitrile side chain to malononitrile (MN). Notably, while liberated MN can subsequently mediate critical AG126 features, full protection in EAE still requires delivery of intact AG126. Its anti‐inflammatory potential and especially interference with TLR signaling thus rely on a dual mechanism encompassing BTK and a novel MN‐sensitive target. Both principles bear great potential for the therapeutic management of disturbed innate and adaptive immune functions. GLIA 2015;63:1083–1099  相似文献   
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