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61.

Objective

Fragrances and strong odors have been characterized as putative triggers that may exacerbate asthma symptoms and many asthmatics readily avoid odors and fragranced products. However, the mechanism by which exposure to pure, non-irritating odorants can elicit an adverse reaction in asthmatic patients is still unclear and may involve both physiological and psychological processes. The aim of this study was to investigate how beliefs about an odor's relationship to asthmatic symptoms could affect the physiological and psychological responses of asthmatics.

Methods

Asthmatics classified as ‘moderate-persistent’, according to NIH criteria, were exposed for 15 min to a fragrance which was described either as eliciting or alleviating asthma symptoms. During exposure, participants were asked to rate odor intensity, perceived irritation and subjective annoyance while physiological parameters such as electrocardiogram, respiratory rate, and end tidal carbon dioxide (etCO2) were recorded. Before, immediately after, and at 2 and 24 h post-exposure, participants were required to subjectively assess their asthma symptom status using a standardized questionnaire. We also measured asthma status at each of those time points using objective parameters of broncho-constriction (spirometry) and measures of airway inflammation (exhaled nitric oxide, FeNO).

Results

Predictably, manipulations of perceived risk altered both the quality ratings of the fragrance as well as the reported levels of asthma symptoms. Perceived risk also modulated the inflammatory airway response.

Conclusions

Expectations elicited by smelling a perceived harmful odor may affect airway physiology and impact asthma exacerbations.  相似文献   
62.
63.
The aims of this article were to describe the surgical technique of the inferior alveolar nerve lateralization followed by implant installation by means of a clinical report and also to discuss the importance of an adequate surgical and prosthetic planning for atrophic posterior mandible rehabilitation.  相似文献   
64.
Here we compare the management and survival outcomes of chronic myeloid leukemia (CML) patients who had early or late imatinib mesylate (IM) therapy. The cytogenetic and molecular responses of 189 CML patients were analyzed. Of this group, 121 patients were classified as the early chronic phase (ECP) group and started IM within 12 months of diagnosis. The other 68 patients were classified as the late chronic phase (LCP) group who had been treated with interferon (IFN)-alpha-2 and crossed over to IM more than 12 months after diagnosis. The overall rates of complete cytogenetic response (CCyR) and major molecular response (MMR) at last follow-up were 83.6 and 78.1% in the ECP and LCP groups, respectively. The CCyR rates were 89.3 (for ECP patients) versus 73.5% (for LCP patients; p < 0.0001). At last follow-up, 82.4% ECP and 64.2% LCP patients had achieved an MMR (p < 0.0001). No significant differences were noted between the two groups with regard to survival outcomes. Our experience reveals that IM is an effective rescue therapy in most CML LCP patients who are intolerant or in whom IFN-alpha therapy fails. Such therapeutic options should be considered in LCP patients, particularly in countries where IM may not be available.  相似文献   
65.

Background:

Pharmacotherapy may not sufficiently reduce neuropathic pain in many individuals post spinal cord injury (SCI). The use of alternative therapies such as surgery may be effective in reducing neuropathic pain in these individuals. However, because of the invasive nature of surgery, it is important to examine the evidence for use of this treatment.

Objective:

The purpose of this study was to conduct a systematic review of published literature on the surgical treatment of neuropathic pain after SCI.

Methods:

MEDLINE, CINAHL, EMBASE, and PsycINFO databases were searched for articles in which surgical treatment of pain after SCI was examined. Articles were restricted to the English language. Article selection was conducted by 2 independent reviewers with the following inclusion criteria: the subjects participated in a surgical intervention for neuropathic pain; at least 50% of the subjects had an SCI; at least 3 subjects had an SCI; and a definable intervention involving the dorsal root entry zone (DREZ) procedure was used to reduce pain. Data extracted included study design, study type, subject demographics, inclusion and exclusion criteria, sample size, outcome measures, and study results. Randomized controlled trials (RCTs) were assessed for quality using the Physiotherapy Evidence Database (PEDro) assessment scale. Levels of evidence were assigned to each intervention using a modified Sackett scale.

Results:

Eleven studies met the inclusion criteria. One study provided level 2 evidence, and the rest provided level 4 evidence. The DREZ procedure was shown to be more effective for segmental pain than for diffuse pain after SCI. Further, individuals with conus medullaris level injury were found to have a higher level of neuropathic pain relief than those with cervical, thoracic, or cauda equina injury.

Conclusions:

The studies demonstrated that the DREZ procedure may be effective in reducing segmental pain. Hence, DREZ may be important in treatment of neuropathic pain in individuals resistant to less invasive treatments. Because the studies lacked control conditions and examination of long-term effects, there is a need for larger trials with more stringent conditions.Key words: pain, spinal cord injury, surgical treatmentPain is a major cause of distress and disability in persons with spinal cord injury (SCI). It has been shown to lead to social isolation, unemployment, decreased function, decreased quality of life, depression, and even suicide.1,2 More than 77% of individuals with an SCI indicated that pain interfered with one or more of their daily activities including sleep (40%), exercise (34.9%), and work (33.6%).2 The International Association for the Study of Pain (IASP) defines neuropathic pain as “pain caused by a lesion or disease of the somatosensory nervous system.”3 After an SCI, individuals often report the onset of chronic neuropathic pain caudal to the level of the lesion or at the same level within the associated spinal cord segment.4 Dijkers et al5 reported no difference in the prevalence of pain based on level or completeness.The reported incidence of neuropathic pain after SCI varies greatly among studies, but between 10% and 30% of patients with SCI experience pain severe enough to interfere with their activities of daily living6,7 and may require surgical intervention to relieve persistent and refractory pain.4,8 Unmanageable neuropathic pain occurs more often in individuals with conus medullaris and cauda equina lesions where damage also involves the peripheral nerve roots.8When pharmacological and other noninvasive treatments fail to reduce pain, surgical spinal cord stimulation and dorsal root entry zone (DREZ) ablation treatments, such as DREZ lesioning and microsurgical DREZotomy (MDT), can be considered as options for the management of refractory pain.9 Neurosurgical procedures to reduce neuropathic pain should be reserved for cases in which medical therapies have failed to sufficiently reduce pain.4 The risks associated with ablative surgeries can be significant for individuals with incomplete neurological deficits; therefore, DREZ ablation is generally only considered a treatment option when neuropathic pain is present after a complete SCI.8 The MDT procedure targets for ablation the nociceptive fibers in the lateral bundle of the dorsal rootlet, the deafferented neurons of the dorsal horn, and the medial portion of the Lissauer tract.4,6 This systematic review was conducted to assess the effectiveness of DREZ ablation therapies in reducing neuropathic pain in individuals following SCI.  相似文献   
66.
67.
胰岛素样生长因子Ⅰ与肝纤维化   总被引:1,自引:1,他引:1  
胰岛素样生长因子I(IGF-I)是体内普遍存在的多肽,循环系统中IGF-I主要来源于肝脏.在垂体生长激素的调控下,IGF-I对多种细胞如成纤维细胞、成骨细胞、平滑肌细胞等的有丝分裂均有调节作用.目前观点认为肝星状细胞(HSC)活化后可分泌大量胶原纤维,是肝纤维化时细胞外基质的主要来源.实验表明 IGF-I能够促进体外培养HSC增殖、活化并抑制其凋亡.而体内研究发现,肝硬化患者血清IGF-I浓度显著下降,外源性小剂量IGF-I 注射能够改善肝功能,为肝纤维化的治疗提供了新的理念.  相似文献   
68.
This paper describes the first controlled study of the relationships among stress, psychological traits associated with chronic anxiety, acid reflux parameters, and perceptions of reflux symptoms. Seventeen subjects with symptomatic reflux disease were studied using a 2 (high vs. low gastrointestinal susceptibility score) × 2 (stress vs. neutral tasks) × 3 (periods 1, 2, or 3) experimental design. It was found that the stress tasks produced significant increases in systolic and diastolic blood pressure, pulse rates, and subjective ratings of anxiety and reflux symptoms. The stress tasks, however, did not influence objective parameters of acid reflux (total acid exposure, number of reflux episodes, duration of longest reflux episode). Moreover, the effect of stress on reflux ratings was due primarily to the responses of the subjects with high gastrointestinal susceptibility scale scores. These subjects reflux ratings remained at high levels during all stress periods, whereas subjects in all other experimental conditions reported decreased reflux symptoms across periods. These results suggest that reflux patients who are chronically anxious and exposed to prolonged stress may perceive low intensity esophageal stimuli as painful reflux symptoms. Future effort should be devoted to examining the efficacy of anxiolytic and behavioral therapies with these reflux patients.  相似文献   
69.

Background  

Wound infections are a common complication of surgery that add significantly to the morbidity of patients and costs of treatment. The global trend towards reducing length of hospital stay post-surgery and the increase in day case surgery means that surgical site infections (SSI) will increasingly occur after hospital discharge. Surveillance of SSIs is important because rates of SSI are viewed as a measure of hospital performance, however accurate detection of SSIs post-hospital discharge is not straightforward.  相似文献   
70.
Ganesan  TS; Min  GL; Goldman  JM; Young  BD 《Blood》1987,70(3):873-876
Four patients with Philadelphia (Ph') positive chronic myeloid leukemia (CML) were studied before, after, and on relapse following allogeneic bone marrow transplantation (BMT). Southern analysis of DNA from cells collected before and at relapse after BMT was performed in order to investigate the origin of the leukemia at relapse. Using minisatellite probes we showed that the relapse occurred in cells of host origin in all four patients and this was confirmed with a Y chromosome specific probe in two male patients who had a female donor. Furthermore, using two probes for the breakpoint cluster region (bcr) on chromosome 22, we showed that leukemic cells at relapse bore identical rearrangements to those in the disease at time of presentation of each patient. We conclude that relapse in all four patients is due to re-emergence of the original leukemic clone.  相似文献   
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