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121.
BACKGROUND: Patients with allergic rhinitis and bronchial hyperresponsiveness (BHR) may be at higher risk of developing asthma. OBJECTIVE: To investigate whether reactivity to aeroallergens in skin prick testing (SPT) and serum eosinophil cationic protein levels can be used to predict BHR in allergic rhinitis patients. METHODS: Fifty-nine consecutive patients with allergic rhinitis underwent SPTs using grass, tree, weed, parietaria, Alternaria, Aspergillus, mites, and cat and dog dander extracts. Methacholine challenge tests were performed using spirometry. RESULTS: Methacholine-induced BHR was detected in 23 patients (39%). Of 59 patients, 14 had 1 positive SPT response, 35 had 2 to 4 positive responses, and 10 had more than 4 positive responses. There was a significant inverse correlation between methacholine provocation concentration that caused a decrease in forced expiratory volume in 1 second of 20% (PC20) and the number of positive SPT responses (r = -0.28; P = .03). The BHR-positive patients had a mean of 4 positive SPT responses, whereas BHR-negative patients had a mean of 2.6 (P = .04). Nine BHR-positive patients (39%) and only 1 BHR-negative patient (3%) had more than 4 positive SPT responses (P < .001). There was no correlation between serum eosinophil cationic protein levels and methacholine PC20 doses. There was a strong association between hyperresponsiveness to methacholine and both cat and dog dander sensitivity (P < .001 and P = .001, respectively). CONCLUSIONS: Allergic rhinitis patients with SPT responses to a higher number of allergens are more likely to have BHR. Whether the number of positive SPT responses correlates with the risk of developing asthma in allergic rhinitis patients remains to be determined.  相似文献   
122.
Recent studies have provided evidence that macrophages from Th1-prone mouse strains respond with an M1 profile, and macrophages from Th2-prone mouse strains respond with an M2 profile, characterized by the dominant production of NO or TGF-beta 1, respectively. We have shown that peritoneal macrophages from IL-12p40 gene knockout mice have a bias toward the M2 profile, spontaneously secreting large amounts of TGF-beta 1 and responding to rIFN-gamma with weak NO production. Moreover, IL-12p40KO macrophages are more permissive to Trypanosoma cruzi replication than their wild-type littermate cells. Prolonged incubation with rIL-12 fails to reverse the M2 polarization of IL-12p40KO macrophages. However, TGF-beta 1 is directly implicated in sustaining the M2 profile because its inhibition increases NO release from IL-12p40KO macrophages. IFN-gamma deficiency is apparently not the reason for TGF-beta 1 up-regulation, because rIFN-gamma KO macrophages produce normal amounts of this cytokine. These findings raise the possibility that IL-12 has a central role in driving macrophage polarization, regulating their intrinsic ability to respond against intracellular parasites.  相似文献   
123.
This study was designed to analyze cytokine levels in bronchoalveolar lavage (BAL) fluid of patients with pulmonary fibrosis (PF) and was performed at a University hospital. Nineteen veterans had mustard gas-induced PF, and 19 normal veterans were used as a control group. Chest roentgenograms, pulmonary function tests (PFTs), the percentage diffusing capacity of carbon monoxide (D(LCO)), high-resolution CT scans of the chest, and analyses of BAL fluids for five cytokines interleukin-8 (IL-8), IL-1beta, IL-6, tumor necrosis factor-alpha (TNF-alpha), IL-12, and the growth factors transforming growth factor-beta (TGF-beta), insulin-like growth factor-1 (IGF-1), and epidermal growth factor (EGF) were performed in all cases. A transbronchial lung biopsy was done in all patients. There were significant differences in cytokine (IL-8, IL-1beta, IL-6, TNF-alpha, IL-12) levels of BAL fluid between patients with PF and healthy controls. TGF-beta, EGF, and IGF-1 levels were also significantly increased in patients with PF compared with controls. A significant negative correlation was observed between the percentage of D(LCO) and IL-8 levels in BAL fluid in patients with PF (r = -0.47, p = 0.04). A significant negative correlation was also seen between the percentage of D(LCO) and TGF-beta (r = 0.53, p = 0.02) in these patients. Except for the percentage and the absolute number of the BAL fluid neutrophils (r = 0.70, p = 0.001 and r = -0.62, p = 0.005, respectively), no correlation was found between D(LCO)% and the other BAL cells. Of all measured cytokines and growth factors, only IL-8 and TGF-beta showed a significant correlation with the degree of fibrosis (p = 0.004, p = 0.04). The increased levels of cytokines and growth factors in the BAL fluid suggest the possible causative mechanism in the lung in sulfur mustard gas-induced PF by recruitment of neutrophils and eosinophils into the lung.  相似文献   
124.
125.
Blood flow in the large systemic arteries is modeled using one-dimensional equations derived from the axisymmetric Navier–Stokes equations for flow in compliant and tapering vessels. The arterial tree is truncated after the first few generations of large arteries with the remaining small arteries and arterioles providing outflow boundary conditions for the large arteries. By modeling the small arteries and arterioles as a structured tree, a semi-analytical approach based on a linearized version of the governing equations can be used to derive an expression for the root impedance of the structured tree in the frequency domain. In the time domain, this provides the proper outflow boundary condition. The structured tree is a binary asymmetric tree in which the radii of the daughter vessels are scaled linearly with the radius of the parent vessel. Blood flow and pressure in the large vessels are computed as functions of time and axial distance within each of the arteries. Comparison between the simulations and magnetic resonance measurements in the ascending aorta and nine peripheral locations in one individual shows excellent agreement between the two. © 2000 Biomedical Engineering Society. PAC00: 8719Uv  相似文献   
126.
127.
Fine-needle aspiration biopsy findings in three cases of chromophobe cell carcinoma are described and correlated with histologic and ultrastructural observations. In addition, comparisons are made with three cases each of oncocytoma and granular cell carcinoma. The cells in aspiration smears from chromophobe cell carcinoma closely correlated with histologic pattern of three cell types which were not present in oncocytomas and granular cell carcinomas. These cells had prominent cell borders, and their cytoplasm was either opaque and granular (type I) or variably translucent and reticular (type II and III). Ultrastructurally, the translucent areas within the cytoplasm contained large numbers of microvesicles which were unique to chromophobe cell carcinoma and were not seen in other neoplasms. Fine-needle aspiration may be used to diagnose chromophobe cell carcinoma and distinguish it from other related renal neoplasms. © 1995 Wiley-Liss, Inc.  相似文献   
128.
Casonis skin test and indirect haemagglutination test (IHA) are still used in Turkey. The preoperative IHA test or Casonis skin test results of 120 patients with surgically confirmed hydatidosis were retrospectively studied during 1997–2004. At the same period, 306 patients with non-hydatid disease had serologic results for echinococcosis. The sensitivity of immediate intradermal reaction, delayed intradermal reaction, and IHA were 70, 62, and 56%, respectively. Casonis skin test components had higher sensitivity than IHA (P<0.01). The specificity of immediate intradermal reaction, delayed intradermal reaction, and IHA were 87, 85, and 84%, respectively. Cystic lesions in non-hydatid patients were localised commonly in the lungs. The occurrence of hydatid disease for pulmonary, hepatic, and renal cysts was 19, 54, and 5%, respectively. An immediate skin reaction to crude hydatid antigens is more useful than IHA.  相似文献   
129.
BACKGROUND: Very few studies have reported cancer outcomes of patients referred through different routes, despite the prominence of current UK cancer urgent referral guidance. AIM: This study aimed to compare outcomes of cancer patients referred through the urgent referral guidance with those who were not, with respect to stage at diagnosis, survival, and delays in diagnosis. Design of study: Analysis of hospital records. SETTING: One hospital trust in England. METHOD: The records of 889 patients diagnosed in 2000-2001 with one of four types of cancer were analysed: 409 with lung cancer; 239 with colorectal cancer; 146 with prostate cancer; and 95 with ovarian cancer. Outcome measures were diagnostic stage, survival, referral and secondary care delays. RESULTS: For lung cancer, urgent referrals had more advanced TNM (tumor, node, metastasis) stage than patients diagnosed through other routes (P = 0.035) and poorer survival (P = 0.020). There was no difference in stage or survival for the other cancers. For each cancer, a higher proportion of urgent referrals was seen within 2 weeks. Secondary care delays for lung and colorectal cancer were shorter for inter-specialty referrals. CONCLUSION: For patients with lung cancer, the guidance appears to be prioritising those in the more advanced stages of disease. This was not the case for the other three cancers. Referral delays were shorter for patients urgently referred, as is the intention of the guidance. The avoidance of delays in outpatient diagnostics probably accounts for shorter secondary care delays for inter-specialty referrals.  相似文献   
130.
A linear mathematical model of the electromyogram (e.m.g.) has been developed for the biceps muscle. The number of motor units (and therefore muscle fibres) contributing to the resultant e.m.g. at any stage of movement has been found from the force analysis of elbow flexion. The depths of various motor units and the phase difference between the recruitment of any two motor units have been formulated using a spiral spread of recruitment sequence. The attenuation of individual motor-unit action potentials due to varying depths has been taken into consideration, and due regard has been taken of the length-tension diagram of a muscle while performing the force analysis. Attention has been focused on the flexion of the elbow joint, in which a method of finding the individual contribution of the biceps and brachialis muscles has been developed and applied. The results predicted by the model have been verified by experiments. The model can also be extended to the e.m.g. of other fast skeletal muscles. The conditions and limitations for such generalisations have been stated and discussed.  相似文献   
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