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31.
32.
Magnetic resonance imaging (MRI) is currently considered an essential complementary method for diagnosis in many conditions. Exponential growth in its use is expected due to the aging population and a broader spectrum of clinical indications. Growth in its use, coupled with an increasing number of pacemaker implants, implantable cardioverter‐defibrillators and cardiac resynchronization therapy, has led to a frequent clinical need for this diagnostic modality in patients with cardiac implantable electronic devices (CIED). This clinical need has fueled the development of devices specifically designed and approved for use in a magnetic resonance (MR) environment under certain safety conditions (MR‐conditional devices). More than a decade after the introduction of the first MR‐conditional pacemaker, there are now several dozen MR‐conditional devices with different safety specifications. In recent years, increasing evidence has indicated there is a low risk to MRI use in conventional (so‐called non‐MR‐conditional) CIED patients in the right circumstances. The increasing number, as well as the greater diversity and complexity of implanted devices, justify the need to standardize procedures, by establishing institutional agreements that require close collaboration between cardiologists and radiologists. This consensus document, prepared jointly by the Portuguese Society of Cardiology and the Portuguese Society of Radiology and Nuclear Medicine, provides general guidelines for MRI in patients with CIED, ensuring the safety of patients, health professionals and equipment. In addition to briefly reviewing the potential risks of MRI in patients with CIED and major changes to MRI‐conditional devices, this article provides specific recommendations on risk‐benefit analysis, informed consent, scheduling, programming strategies, devices, monitoring and modification of MRI sequences. The main purpose of this document is to optimize patient safety and provide legal support to facilitate easy access by CIED patients to a potentially beneficial and irreplaceable diagnostic technique.  相似文献   
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To evaluate differences in tissue composition between hearts with pressure overload hypertrophy and normal hearts of comparable weight, 30 rat hearts with aortic constriction of 4, 10 and 30 days, and nine hearts of sham operated controls were studied. Surgery was performed at age 70 days. Morphometric analysis of myocardial tissue sections revealed (1) myocyte hypertrophy in left ventricular myocardium of hypertrophic hearts was proportional to heart weight, and in normal growth myocyte volume increased in proportion to heart weight; (2) myocyte number in left ventricular myocardium was identical in hypertrophic and normal hearts; (3) non-muscle cell proliferation was proportional to heart weight identically in hypertrophic and normal hearts; (4) volume fractions of myocytes were significantly lower in hypertrophic hearts [0.76(SD 0.05)] than in normal hearts [0.82(0.04)]; (5) volume fractions of all nuclei, myocyte nuclei and non-myocyte nuclei were similar in hypertrophic and normal hearts; (6) measured ventricular DNA content increased with heart weight identically in hypertrophic and normal hearts, and equalled DNA content calculated using the data on tissue composition. Neither right ventricular weight nor right ventricular DNA content were affected by the presence of left ventricular hypertrophy. We conclude that left ventricular hypertrophy due to aortic constriction in the rat resulted in changes of myocardial tissue composition similar to the changes associated with normal growth. Tissue composition of hypertrophic rat hearts corresponds strikingly to that of normal rat hearts with comparable heart weight, although myocardial changes in hypertrophy develop considerably faster than in normal growth.  相似文献   
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36.

Objective and design

The activation of proteinase-activated receptors (PARs) has been implicated in the development of important hallmarks of inflammation, including in vivo leukocyte recruitment; however, its role in the regulation of leukocyte migration in response to inflammatory stimuli has not been elucidated until now. Here, we examined the effects of the PAR4 antagonist YPGKF-NH 2 (tcY-NH2) on neutrophil recruitment in experimentally induced inflammation.

Methods

BALB/c mice were intrapleurally injected with tcY-NH2 (40 ng/kg) prior to intrapleural injection of carrageenan (Cg) or neutrophil chemoattractant CXCL8; the number of infiltrating neutrophils was evaluated after 4 h, and KC production was assessed at different times after Cg injection. Neutrophil adhesion and rolling cells were studied using a brain circulation preparation 4 h after the Cg or CXCL8 challenge in tcY-NH2-treated mice.

Results

PAR4 blockade inhibited CXCL8- and Cg-induced neutrophil migration into the pleural cavity of BALB/c mice and reduced neutrophil rolling and adherence. Surprisingly, PAR4 blockade increased the level of KC in response to carrageenan.

Conclusion

These results demonstrated that PAR4 blockade impairs neutrophil migration in vivo, suggesting that PAR4 plays an important role in the regulation of inflammation, at least in part because of its ability to inhibit the actions of the neutrophil chemoattractant CXCL8.  相似文献   
37.

Context:

Abnormal movement patterns have been implicated in lower extremity injury. Reliable, valid, and easily implemented assessment methods are needed to examine existing musculoskeletal disorders and investigate predictive factors for lower extremity injury.

Objective:

To determine the reliability of experienced and novice testers in making visual assessments of lower extremity movement patterns and to characterize the construct validity of the visual assessments.

Design:

Cross-sectional study.

Setting:

University athletic department and research laboratory.

Patients or Other Participants:

Convenience sample of 30 undergraduate and graduate students who regularly participate in athletics (age = 19.3 ± 4.5 years). Testers were 2 experienced physical therapists and 1 novice postdoctoral fellow (nonclinician).

Main Outcome Measure(s):

We took videos of 30 athletes performing the single-legged squat. Three testers observed the videos on 2 occasions and classified the lower extremity movement as dynamic valgus, no change, or dynamic varus. The classification was based on the estimated change in frontal-plane projection angle (FPPA) of the knee from single-legged stance to maximum single-legged squat depth. The actual FPPA change was measured quantitatively. We used percentage agreement and weighted κ to examine tester reliability and to determine construct validity of the visual assessment.

Results:

The κ values for intratester and intertester reliability ranged from 0.75 to 0.90, indicating substantial to excellent reliability. Percentage agreement between the visual assessment and the quantitative FPPA change category was 90%, with a κ value of 0.85.

Conclusions:

Visual assessments were made reliably by experienced and novice testers. Additionally, movement-pattern categories based on visual assessments were in excellent agreement with objective methods to measure FPPA change. Therefore, visual assessments can be used in the clinic to assess movement patterns associated with musculoskeletal disorders and in large epidemiologic studies to assess the association between lower extremity movement patterns and musculoskeletal injury.Key Words: movement analysis, screening, athletic injuries, knee valgus

Key Points

  • With training and the use of standardized techniques, both experienced and novice testers reliably classified lower extremity movement patterns based on visual assessment.
  • Movement-pattern category-based visual assessments were in excellent agreement with objective methods to measure changes in frontal-plane projection angle.
  • Visual assessment based on the methods described in this study may be used in the clinical setting, as well as in large epidemiologic studies and screening assessments for sport participation, to identify distinct categories of lower extremity movement patterns.
Abnormal movement patterns of the lower extremity have been implicated in noncontact anterior cruciate ligament (ACL) injuries1 and other musculoskeletal problems, such as patellofemoral pain24 and acetabular labral tears.5 In addition, correcting these abnormal movement patterns has been shown to prevent ACL injury6 and is proposed to reduce symptoms in people with preexisting pain conditions.5,7,8 Thus, assessment of lower extremity movement patterns may be a way to guide treatment of existing musculoskeletal pain problems and to identify people at risk for future injury or musculoskeletal pain. To facilitate the examination of existing musculoskeletal disorders and the investigation of predictive factors of lower extremity injury, reliable, valid, and feasible methods to assess lower extremity movement patterns are needed.One method to assess lower extremity movement patterns is the Landing Error Scoring System (LESS).911 The LESS uses a standard technique to make visual assessments of movement patterns during a drop vertical jump. The LESS is reliable and valid911; however, the drop vertical jump is a relatively high-level activity and may not be the best way to assess movement patterns in patients with existing injury or in athletes whose sports do not involve landing from a jump. In addition, the drop vertical jump is a bilateral activity that may allow the participant to use 1 limb to compensate for the other. Visual assessment of the single-legged squat (SLSquat), a unilateral limb task, may provide an alternative to the LESS.We have developed standardized methods using a visual assessment of the frontal-plane projection angle (FPPA) to classify the lower extremity movement pattern during an SLSquat. The FPPA is a 2-dimensional (2-D) representation of the lower extremity position12 and has been used to identify differences between men and women12 and between women with patellofemoral pain and control participants4,13 and to detect change in movement patterns after specific training.14 We established specific criteria to define the categories of lower extremity movement pattern based on the change in FPPA (FPPA change) during motion. The tester observes the angle formed between a line that bisects the thigh and a line that bisects the lower leg. During movement tests, the tester compares the FPPA at the start position with the FPPA at the end position. For example, to assess an SLSquat, the examiner compares the FPPA during the start position of single-legged stance with the end position of maximum squat depth. The difference observed in FPPA from the start to the end position can then be classified as dynamic valgus (change in the valgus direction), no change, or dynamic varus (change in the varus direction). We have used this assessment extensively in the clinical setting, but we have not assessed the rater reliability or the construct validity of our visual assessments.The purpose of this study was to assess the intratester and intertester reliability of 3 testers (2 experienced, 1 novice) categorizing the lower extremity movement pattern demonstrated during an SLSquat. A standardized protocol was used to assess videos of healthy participants performing the SLSquat. We hypothesized that the testers, both experienced and novice, would demonstrate good to excellent reliability using the standardized methods. In addition, we used the objective measure of quantifying FPPA as described by Willson and Davis12 to determine the construct validity of our visual assessments. We hypothesized that we would see good to excellent agreement between our visual assessments and the quantitative FPPA change.  相似文献   
38.
Gingival overgrowth (GO) may be related to the frequent use of certain medications, such as cyclosporin, phenytoin (PHT), and nifedipine, and is therefore denominated drug-induced GO. This article reports a case of a patient who with chronic periodontitis made use of PHT and presented generalized GO. A 30-year-old man with GO was referred to the clinic of the Universidade Estadual Paulista, Brazil. The complaint was poor aesthetics because of the GO. The patient had a medical history of a controlled epileptic state, and PHT was administered as an anticonvulsant medication. The clinical examination showed generalized edematous gingival tissues and presence of bacterial plaque and calculus on the surfaces of the teeth. The diagnosis was GO associated with PHT because no other risk factors were identified. Treatment consisted of meticulous oral hygiene instruction, scaling, root surface instrumentation, prophylaxis, and daily chlorhexidine mouth rinses. After this stage, periodontal surgery was performed, and histopathologic evaluation was made. The patient has been under control for 3 years after the periodontal surgery, and up to the present time, there has been no recurrence. It can be concluded that PHT associated with the presence of irritants favored gingival growth and that the association of nonsurgical and surgical periodontal therapies was effective in the treatment of GO. Besides, motivating the patient to maintain oral hygiene is a prerequisite for the maintenance of periodontal health.  相似文献   
39.
Graefe's Archive for Clinical and Experimental Ophthalmology - To assess the outcomes of vitrectomy with or without cataract surgery for the treatment of idiopathic ERM in phakic eyes and...  相似文献   
40.
The purpose of this review is to describe and critically evaluate current knowledge regarding diagnosis, assessment, and management of chronic overload leg injuries which are often non-specific and misleadingly referred to as ‘shin splints’. We aimed to review clinical entities that come under the umbrella term ‘Exercise-induced leg pain’ (EILP) based on current literature and systematically searched the literature. Specifically, systematic reviews were included. Our analyses demonstrated that current knowledge on EILP is based on a low level of evidence. EILP has to be subdivided into those with pain from bone stress injuries, pain of osteo-fascial origin, pain of muscular origin, pain due to nerve compression and pain due to a temporary vascular compromise. The history is most important. Questions include the onset of symptoms, whether worse with activity, at rest or at night? What exacerbates it and what relieves it? Is the sleep disturbed? Investigations merely confirm the clinical diagnosis and/or differential diagnosis; they should not be solely relied upon. The mainstay of diagnosing bone stress injury is MRI scan. Treatment is based on unloading strategies. A standard for confirming chronic exertional compartment syndrome (CECS) is the dynamic intra-compartmental pressure study performed with specific exercises that provoke the symptoms. Surgery provides the best outcome. Medial tibial stress syndrome (MTSS) presents a challenge in both diagnosis and treatment especially where there is a substantial overlap of symptoms with deep posterior CECS. Conservative therapy should initially aim to correct functional, gait, and biomechanical overload factors. Surgery should be considered in recalcitrant cases. MRI and MR angiography are the primary investigative tools for functional popliteal artery entrapment syndrome and when confirmed, surgery provides the most satisfactory outcome. Nerve compression is induced by various factors, e.g., localized fascial entrapment, unstable proximal tibiofibular joint (intrinsic) or secondary by external compromise of the nerve, e.g., tight hosiery (extrinsic). Conservative is the treatment of choice. The localized fasciotomy is reserved for recalcitrant cases.  相似文献   
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