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81.
Psoriasis is a chronic inflammatory disease associated with several comorbidities. Osteoporosis is defined as a reduction in bone mineral density with impaired bone microarchitecture. Several mechanisms may be implicated as a possible cause for the association between psoriasis and osteoporosis, such as systemic inflammation, anti‐psoriatic drug intake and joint dysfunction for psoriatic arthritis (PsA). The aim of the present study was to assess bone mineral density (BMD) in patients with psoriasis, correlating the prevalence of osteopenia/osteoporosis with Psoriasis Area and Severity Index (PASI) score, mean duration of psoriatic disease, PsA and previous treatments for psoriasis. Forty‐three consecutive patients with psoriasis, 19 of whom were affected by the arthropathic form, were enrolled. We evaluated the severity of psoriasis as measured by PASI score, the CASPAR criteria and ultrasounds of the joints to verify the diagnosis of PsA and the age of psoriasis onset to estimate mean disease duration. Patients underwent a bone density scan of the lumbar spine and femoral neck by dual‐energy X‐ray absorptiometry to measure BMD. Patients with osteopenia/osteoporosis showed a statistically significant longer average duration of psoriatic disease (17 years), compared to patients affected by psoriasis with normal T‐score (8.8 years) (P = 0.04). The linear logistic regression confirms a significant relation between mean psoriatic disease duration and BMD alterations (P = 0.04). Our results suggest the necessity of an early diagnostic evaluation of bone metabolism in patients with psoriasis, especially if characterized by longer disease duration.  相似文献   
82.
The potential of sublingual (s.l.) delivery of vaccine was examined in mice. We show the existence of a dense network of dendritic cells (DCs) in the s.l. epithelium and a rapid and transient increase in the frequency of s.l. DCs after topical application of cholera toxin (CT) adjuvant under the tongue. S.l. immunization with ovalbumin and CT induced vigorous systemic and mucosal antibody responses. Such treatment promoted mixed Th1 and Th2 cytokine responses and induced cytotoxic CD8(+) T cells in lung tissues and in systemic lymphoid organs. S.l. immunization was comparable to intranasal immunization and was superior to oral immunization regarding the magnitude and anatomic dissemination of the induced immune responses. S.l. administration of live influenza virus at a dose lethal by the nasal route was well tolerated and did not redirect virus to the olfactory bulb. These features underscore the potential of the s.l. mucosa to serve as an alternative vaccine delivery route.  相似文献   
83.
败血症是新生儿重症监护室(NICU)的危重病症及造成新生儿死亡的重要原因之一,根据其发病时间,可分为早发(生后2 d 内)和晚发(生后2 d 后)。其中晚发的新生儿败血症,一般考虑为院内感染(NI)。胎龄越小,出生体重越低,NI 的发生率越高。NI 的发生率在加拿大各 NICU 之间差别较大,与各中心医护人员的相关诊疗行为密切相关。在国家卫生研究院"基于循证医学的医疗质量改进项目" 的推动下,2003~2009 年间加拿大全国 NICU 总的NI 率明显下降,但不同中心各自感染率的变化趋势仍极为不同。本研究纳入了加拿大全国共24 家 NICU 在2008~2012 年间所有收入院的胎龄<33 周的早产儿共18 961 名,探讨NI 率的变化趋势以及其与早产儿预后的关系。  相似文献   
84.

BACKGROUND

Sensemaking is the social act of assigning meaning to ambiguous events. It is recognized as a means to achieve high reliability. We sought to assess sensemaking in daily patient care through examining how inpatient teams round and discuss patients.

OBJECTIVE

Our purpose was to assess the association between inpatient physician team sensemaking and hospitalized patients’ outcomes, including length of stay (LOS), unnecessary length of stay (ULOS), and complication rates.

DESIGN

Eleven inpatient medicine teams’ daily rounds were observed for 2 to 4 weeks. Rounds were audiotaped, and field notes taken. Four patient discussions per team were assessed using a standardized Situation, Task, Intent, Concern, Calibrate (STICC) framework.

PARTICIPANTS

Inpatient physician teams at the teaching hospitals affiliated with the University of Texas Health Science Center at San Antonio participated in the study. Outcomes of patients admitted to the teams were included.

MAIN MEASURES

Sensemaking was assessed based on the order in which patients were seen, purposeful rounding, patient-driven rounding, and individual patient discussions. We assigned teams a score based on the number of STICC elements used in the four patient discussions sampled. The association between sensemaking and outcomes was assessed using Kruskal-Wallis sum rank and Dunn’s tests.

KEY RESULTS

Teams rounded in several different ways. Five teams rounded purposefully, and four based rounds on patient-driven needs. Purposeful and patient-driven rounds were significantly associated with lower complication rates. Varying the order in which patients were seen and purposefully rounding were significantly associated with lower LOS, and purposeful and patient-driven rounds associated with lower ULOS. Use of a greater number of STICC elements was associated with significantly lower LOS (4.6 vs. 5.7, p = 0.01), ULOS (0.3 vs. 0.6, p = 0.02), and complications (0.2 vs. 0.5, p = 0.0001).

CONCLUSIONS

Improving sensemaking may be a strategy for improving patient outcomes, fostering a shared understanding of a patient’s clinical trajectory, and enabling high reliability.KEY WORDS: complexity science, sensemaking, length of stay, complication rates, inpatient teams  相似文献   
85.

Background

Canes are usually prescribed for individuals with stroke with the purpose of improving walking and increasing safety. However, there is no consensus regarding the clinical effects of these aids on walking and participation.

Objective

This study will examine the efficacy of the provision of a cane to improve walking and increase participation after stroke.

Methods

This is a two-arm, prospectively registered, randomized trial with concealed allocation, blinded measurers, and intention-to-treat analysis. Fifty individuals with chronic stroke, categorized as slow or intermediate walkers (walking speeds ≤0.8 m/s), will participate. The experimental group will receive a single-point cane and instructions to use the cane anytime they need to walk. The control group will receive a placebo intervention, consisting of self-stretching exercises of the lower limb muscles and instructions to not use assistive devices. The primary outcome will be comfortable walking speed. Secondary outcomes will include walking step length, walking cadence, walking capacity, walking confidence, and participation. Outcomes will be collected by a researcher blinded to group allocation at baseline (Week 0), after intervention (Week 4), and one month beyond intervention (Week 8).

Conclusion

The provision of a single-point cane may help improving walking of slow and intermediate walkers after stroke. If walking is enhanced, the benefits may be carried over to participation, and individuals may experience greater free-living physical activity at home and in the community.  相似文献   
86.
87.
Keratoconus is a slowly progressive, noninflammatory ectatic corneal disease characterized by changes in corneal collagen structure and organization. Though the etiology remains unknown, novel techniques are continuously emerging for the diagnosis and management of the disease. Demographical parameters are known to affect the rate of progression of the disease. Common methods of vision correction for keratoconus range from spectacles and rigid gas-permeable contact lenses to other specialized lenses such as piggyback, Rose-K or Boston scleral lenses. Corneal collagen cross-linking is effective in stabilizing the progression of the disease. Intra-corneal ring segments can improve vision by flattening the cornea in patients with mild to moderate keratoconus. Topography-guided custom ablation treatment betters the quality of vision by correcting the refractive error and improving the contact lens fit. In advanced keratoconus with corneal scarring, lamellar or full thickness penetrating keratoplasty will be the treatment of choice. With such a wide spectrum of alternatives available, it is necessary to choose the best possible treatment option for each patient. Based on a brief review of the literature and our own studies we have designed a five-point management algorithm for the treatment of keratoconus.  相似文献   
88.
BACKGROUND AND AIMS: Fractalkine, a chemokine that presents as both a secreted and a membrane-anchored form, has been described as having tumour-suppressive activities in standard subcutaneous models. Here, we investigate the antitumour effect of fractalkine, in its three molecular forms, in two orthotopic models of metastatic colon cancer (liver and lung) and in the standard subcutaneous model. METHODS: We have developed models of skin tumours, liver and pulmonary metastasis and compared the extent of tumour development between C26 colon cancer cells expressing either the native, the soluble, the membrane-bound fractalkine or none. RESULTS: The native fractalkine exhibits the strongest antitumour effect, reducing the tumour size by 93% in the skin and by 99% in the orthotopic models (p<0.0001). Its overall effect results from a critical balance between the activity of the secreted and the membrane-bound forms, balance that is itself dependent on the target tissue. In the skin, both molecular variants reduce tumour development by 66% (p<0.01). In contrast, the liver and lung metastases are only significantly reduced by the soluble form (by 96%, p<0.002) whereas the membrane-bound variant exerts a barely significant effect in the liver (p = 0.049) and promotes tumour growth in the lungs. Moreover, we show a significant difference in the contribution of the infiltrating leukocytes to the tumour-suppressive activity of fractalkine between the standard and the orthotopic models. CONCLUSIONS: Fractalkine expression by C26 tumour cells drastically reduces their metastatic potential in the two physiological target organs. Both molecular forms contribute to its antitumour potential but exhibit differential effects on tumour development depending on the target tissue.  相似文献   
89.

Background

Inhibition of intestinal peristalsis is a major side effect of opioid analgesics. Although tramadol is an opioid-like analgesic, its effect on gut motility is little known. Therefore, the effect of (+)-tramadol, (-)-tramadol and the major metaboliteO-desmethyltramadol on intestinal peristalsisin vitro and their mechanisms of action were examined. Distension-induced peristalsis was recorded in fluid-perfused segments of the guinea pig small intestine. The intraluminal peristaltic pressure threshold (PPT) was used to quantify the motor effects of extraserosally administered drugs.

Results

Racemic tramadol, its (+)- and (-)-enantiomers and the major metaboliteO-desmethyltramadol (0.1 – 100 μM) concentration-dependently increased PPT until peristalsis was transiently or persistently abolished. The rank order of potency was (-)-tramadol < (+)-tramadol <O-desmethyltramadol. The peristaltic motor inhibition caused by (+)- and (-)-tramadol was markedly and that ofO-desmethyltramadol nearly completely prevented by naloxone, but left unaltered by the 5-hydroxytryptamine receptor antagonists methysergide plus tropisetron. The adrenoceptor antagonists prazosin plus yohimbine reduced the effect of (+)- and (-)-tramadol but not that ofO-desmethyltramadol.

Conclusion

The results show that the metaboliteO-desmethyltramadol is more potent in inhibiting peristalsis than its parent compound. The action of all tramadol forms depends on opioid receptors, and that of (+)- and (-)-tramadol also involves adrenoceptors.  相似文献   
90.
Tissue factor (TF) is the principal cellular initiator of normal blood coagulation. As a result it is considered to be a major regulator of haemostasis and thrombogenesis. In vivo TF activity is regulated by specific circulating inhibitor known as "tissue factor pathway inhibitor (TFPI)". TF is also essential for other cellular processes including embryogenesis and angiogenesis as well as in implantation where it is particularly important in the first trimester. TF is highly expressed in syncytiotrophoblasts (STB) while TFPI is expressed in human umbilical vein endothelial cells (HUVEC). TFPI may be internalized via an endocytic pathway and recycled to the cell surface. The procoagulant tendency of STB may reflect a physiological need for immediate inhibition of hemorrhage in the placental intervillous spaces. Furthermore, the haemostatic balance involving STB and HUVEC may be critical for normal placental function and pregnancy outcome. Homozygous knockouts of both TF and TFPI are generally lethal in fetal mice; heterozygotes survive but with altered coagulation parameters. Despite their apparent association with placental microcirculation-thrombi-formation only few studies have addressed the role of TF and TFPI in the pathogenesis of gestational vascular complications. In this context, detailed studies could provide clinically relevant information.  相似文献   
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