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751.
We examined the use of 23 diagnostic procedures and monitoring tests for users of disease-modifying therapy (DMT) and non-DMT users with multiple sclerosis (MS). The Medstat MarketScan(?) Commercial Claims and Encounters database (2003-2007), which is composed of medical and pharmacy claims for approximately 8 million beneficiaries from 45 US commercial health plans, was used to identify DMT users with an index claim for an MS drug and a 6-month baseline period without MS drugs. Patients were followed for 12 months. Logistic regression models were used to estimate differences in rates and proportion of patients receiving procedures and tests between cohorts. Baseline rates for DMT users (n = 12,455) included MRIs (76.8%), spinal taps (15.7%), neuropsychological testing (4.7%), chemistry panels (61.4%), complete blood cell counts (76.7%) and liver function tests (60.5%). Relative to non-DMT users (n = 25,534), DMT users were more likely to receive an MRI, neuropsychological testing, chemistry panels, complete blood cell counts and liver function tests.  相似文献   
752.
753.

Background

Although every step in the in vitro fertilisation (IVF) procedure is important, the impact of embryo transfer (ET) on pregnancy rate (PR) is significant. Of all the crucial aspects of ET the type of catheter used and the technique of transfer on the PR has drawn the maximum attention and controversy. We aimed to compare the outcome of two different ET catheters on the PR.

Method

A prospective analysis comparing the classical Frydman (Laboratoire CCD, France) and the soft Cook (Cook Medical, Indiana, USA) ET catheters was performed. Primary end-point was clinical pregnancy rate (CPR); secondary end-points were rates of difficult transfer. A total of 1,446 ETs were performed in women undergoing IVF treatment, of which 723 cycles were randomised to the Cook catheter and 723 to the Frydman catheter.

Results

It was observed that, although the Cook catheter was related to a slightly higher PR, the overall comparison failed to indicate a significant difference in CPR. It was also seen that the ease of transfer did not significantly affect the PRs.

Conclusion

Individual variables during ET may not contribute significantly to the success of an IVF programme; however, a holistic approach encompassing all the factors is quintessential to improve the PR.  相似文献   
754.
A set of proteins is a complex system whose elements are interrelated on the concept of sequence- and structure-based similarity. Here, we applied a similarity network-based methodology for the representation and analysis of protein sequences and structures sets using a non-redundant set of 311 proteins and three different information criteria based on sequence-derived features, sequence local alignment and structural alignment. A wide set of measurements, like network degree, clustering coefficient, characteristic path length and vertex centrality were utilized to characterize the networks’ topology. Protein similarity networks were found medium or highly interconnected and the existence of both clusters and random edges classified their fully connected versions as Small World Networks (SWNs). The SWN architecture was able to host the continuous similarity transition among proteins and model the protein information flow during evolution. Recently reported ancestral elements, like the α/β class and certain folds, were remarkably found to act as hubs in the networks. Additionally, the moderate information value of sequence-derived features when used for fold and class assignment was shown on a network basis. The methodology described here can be applied for the analysis of other complex systems which consist of interrelated elements and a certain information flow.  相似文献   
755.
The purpose of this study was to examine the effect of spatial resolution of visual feedback on the variability and structure of isometric force. We manipulated spatial resolution of the display by changing the number of possible feedback dot positions. Twelve healthy young adults (5 men, 7 women) attempted to apply a constant level of force normal to a load cell with the index finger using two types of visual displays. One display provided high spatial resolution visual feedback by allowing feedback dot take any position from the 440 pixels along the vertical dimension of the screen. This display provided precise information about the current level of force relative to the target and to a range of allowable force deviation around the target. The other display provided low spatial resolution visual feedback by depicting applied force as taking on only three discrete values—below, within, or above the target range. Participants produced less variable and more complex (higher approximate entropy) force output with the displays that had higher spatial resolution. Recurrence quantification analysis of the force time series revealed that the display with low visual feedback resolution promoted a more intermittent, discontinuous force-production performance.  相似文献   
756.
The transient receptor potential channel subtypes V1 (TRPV1) and A1 (TRPA1) play a critical role in the development of hyperalgesia in inflammatory pain models. Although several studies in animals and humans have demonstrated that capsaicin (CAP), a TRPV1-specific agonist, and mustard oil (MO), a TRPA1 agonist, evoke responses that undergo functional cross-desensitization in various models, the mechanisms mediating this phenomenon are largely unknown. In the present study, we evaluated the mechanisms underlying homologous and heterologous desensitization between CAP and MO responses in peripheral nociceptors using an in vitro neuropeptide release assay from acutely isolated rat hindpaw skin preparation and in vivo behavioral assessments. The pretreatment with CAP or MO significantly inhibited (50-60%) both CAP- and MO-evoked CGRP release indicating homologous and heterologous desensitization using this assay. Further studies evaluating the requirement of calcium in these phenomena revealed that homologous desensitization of CAP responses was calcium-dependent while homologous desensitization of MO responses was calcium-independent. Moreover, heterologous desensitization of both CAP and MO responses was calcium-dependent. Further studies evaluating the role of calcineurin demonstrated that heterologous desensitization of CAP responses was calcineurin-dependent while heterologous desensitization of MO responses was calcineurin-independent. Homologous and heterologous desensitization of CAP and MO was also demonstrated using in vivo behavioral nocifensive assays. Taken together, these results indicate that TRPV1 and TRPA1 could be involved in a functional interaction that is regulated via different cellular pathways. The heterologous desensitization of these receptors and corresponding inhibition of nociceptor activity might have potential application as a therapeutic target for developing novel analgesics.  相似文献   
757.
BACKGROUND: The most effective method of increasing the level of estrogen in the wounds of post-menopausal women undergoing routine surgical procedures is by long-term preoperative administration. However, in the case of acute surgery or trauma, the most effective method of increasing the level of estrogen is administration immediately pre- or postsurgery. This study, therefore, was aimed at assessing the effect of postsurgical administration of estradiol benzoate on wound healing in ovariectomized (OVX) Sprague Dawley rats. MATERIALS AND METHODS: Three months prior to the wound healing experiment, 16 rats were anesthetized and underwent ovariectomy, while the other eight rats were sham operated. Two parallel full thickness skin incisions and two round full thickness skin excisions were performed on the dorsum of each rat. Dose of 10 microg/d of estradiol benzoate was administered to eight OVX rats for 6 d postoperatively, whereas the other animals received a placebo. After 6 d, all animals were sacrificed and samples removed for biomechanical and histological evaluation. RESULTS: The mean wound tensile strength of OVX estrogen treated rats (9.54 +/- 3.24 g/mm(2)) was significantly lower compared with vehicle-treated OVX animals (14.57 +/- 4.12 g/mm(2)) as well as with control rats subjected to sham-OVX surgery (11.71 +/- 3.33 g/mm(2)). Nevertheless, the histological evaluation in OVX estrogen treated rats showed a significantly increased process of neo-angiogenesis associated with slightly decreased collagen deposition. CONCLUSION: Our results indicate that the question of the clinical significance of this type of hormone replacement therapy remains open and requires further research.  相似文献   
758.
In dermatology, clinical photographs are an essential component of patient care, enabling clinicians to document changes in skin pathology over time. Recent advances in digital technology and the electronic medical record have revolutionized clinical photography; however, these advances bring with them new ethical, legal, and social concerns. Photographs, more than other forms of documentation, have the potential to make patients uncomfortable. The act of photography, especially for those images requiring exposure of the genital area or the entire body, can be an uncomfortable experience for patients, necessitating the clinician and photographer to take an empathic stance in this setting. The Internet has elicited an increasing, and a very real, concern for patients about possible distribution and use of images outside of their individual care. The clinician and staff can allay these fears by professionally and empathetically addressing their concerns. In addition, it is important that patients receive appropriate informed consent about clinical photographs and the potential use of the images in their care, education, and research. Given the multitude of methods for recording clinical photographs, combined with the increasing complexity of image storage, standardization becomes a critical tool in providing consistency among images and achieving more equitable and efficacious care. To achieve this goal and improve the baseline standard of continuity of care for dermatological practices, we review the role of photographs, develop a model for patient consent, and establish standards for photography so as to provide the most ethical care for the patient.  相似文献   
759.
Iron-deficiency anemia can have deleterious effects on the heart. Herein, we describe the effects of iron deficiency on the heart as corroborated with electrocardiography, radiology, echocardiography, and cardiac catheterization. We review the pathophysiology, clinical features, and management of iron-deficiency-induced cardiomyopathy.  相似文献   
760.
A novel and efficient implementation of the marching cubes algorithm.   总被引:5,自引:0,他引:5  
In this paper, a novel and efficient implementation of the marching cubes (MC) algorithm is presented for the reconstruction of anatomical structures from real three-dimensional medical data. The proposed approach is based on a generic rule, able to triangulate all 15 standard cube configurations used in the classical MC algorithm as well as additional cases presented in the literature. The proposed implementation of the MC algorithm can handle the Type A 'hole problem' which occurs when at least one cube face has an intersection point in each of its four edges. Theoretical and experimental results demonstrate the ability of the new implementation to reproduce standard MC results, resolving Type A 'hole problem'. Finally, the proposed implementation was applied to real medical date to reconstruct anatomical structures. The output of the proposed technique is in WWW compliant format.  相似文献   
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