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991.
Several cytokines play significant roles in the development and pathogenesis of pleural effusion. Little is known, however, about possible interactions between individual cytokines in terms of regulation of their relative abundance in the effusion. We studied 93 patients presenting with pleural effusion to the National Sanyo Hospital (68 men and 25 women; mean age, 64 years). Twenty-two patients had tuberculous pleurisy, 40 had malignant pleuritis, and 31 had effusions due to an etiology other than tuberculosis or cancer (miscellaneous). Pleural fluid concentrations of IL-2, IL-4, IL-5, IL-10, TNF-alpha, and INF-gamma were simultaneously measured by cytometric bead array (CBA). The ratios of IL-4/IL-5, IL-4/TNF-alpha, IL-2/TNF-alpha, and IL-10/TNF-alpha were lower in patients with tuberculosis pleurisy compared with other patients. In all three groups of patients significant correlation was seen between abundance of IL-2 vs. IL-4, IL-5, IL-10, or TNF-alpha, between IL-4 vs. IL-10, and between TNF-alpha vs. INF-gamma. In malignant pleural fluid patients, the significant correlation was between IL-2 vs. IL-4, TNF-alpha, or INF-gamma, between IL-4 vs. INF-gamma, and between TNF-alpha vs. INF-gamma. In tuberculosis pleural fluid patients, the significant correlation was between IL-2 vs. TNF-alpha, between IL-4 vs. IL-10, and between TNF-alpha vs. INF-gamma. In miscellaneous pleural fluid patients, the significant correlation was between IL-2 vs. IL-4, IL-10, or TNF-alpha, between IL-4 vs. IL-10, TNF-alpha, and between IL-10 vs. TNF-alpha. No significant correlation was observed between other pairs of cytokines. Strong correlation in abundance between particular cytokines in pleural fluids suggests cross-talk between them, in terms that an altered level of one of them provides a feedback mechanism regulating synthesis and/or secretion of another one. Such interactions may play important roles in pathogenesis and severity of the effusion. The CBA methodology provides a convenient tool to investigate these interactions.  相似文献   
992.
993.
To determine the immunisation coverage for HBV and the prevalence of HBsAg an anonymous serosurvey of consecutive adult surgical/gynaecologic patients presenting to 16 randomly selected hospitals in West Pomerania, Poland, was conducted. Immunisation rate was 60.4%, of these 69.7% had received the complete course of three doses; 65.2% were immunised at the request of referring surgeons. The multivariable regression model revealed that age <40 years, low educational status, not having a surgery in the past, tattoo application, and emergency procedure were each associated with a greater odds of not being vaccinated. HBsAg prevalence was 0.6%. Authors conclude that the preoperative vaccination policy might be an effective public health tool to limit the spread of the epidemic.  相似文献   
994.
History of oral allergy syndrome goes back to 1987 year, when Amlot for the first time used this name for pollen-food cross-reactive reactions. Since that time many kinds of various reactions between pollens and different food had been described. Is seems that after almost 20 years the knowledge about this highly prevalent phenomenon is still incomplete and not well known among specialist other than allergologists. We try to reach consensus on several aspects of this food-induced syndrome, which may be helpful in laryngological practice. It is very important especially for more severe immediate reactions which can occurred, like pharynx and larynx swelling with asphyxia, or anaphylaxis. Today OAS diagnosis is based on the patient's history and RAST. Most of patients gave a history of oral symptoms like oral irritation, throat tightness, lips, oral and throat swelling, oral mucosal blebs. This local symptoms quickly disappear and are not particularly serious but they may proceed to urticaria, asthma, abdominal pain and anaphylaxis. Treatment of OAS include; food avoidance, drugs and specific immunotherapy. Patients with pollen allergy should be informed about the possibility of hypersensitivity to certain fruits and vegetables.  相似文献   
995.
Conventional four-pass differential synthetic aperture radar interferometry (DInSAR) assumes that there are no significant changes in the ground during the period between the acquisition times of SAR images for topographic DInSAR pairs. This assumption can rarely be satisfied for glacial areas due to their continuous movement. This letter proposes a modified four-pass DInSAR method without an external digital elevation model (DEM), taking into account glacier movement between the acquisition times of SAR images used to form topographic DInSAR pairs. An explicit expression of theoretical formulas for a modified four-pass DInSAR technique was derived for the first time, revealing that four-pass DInSAR considering ground movement of topographic pairs was equivalent to that of conventional four-pass DInSAR with a spatially varying nominal wavelength. Then the proposed method was tested with four Advanced Land Observing Satellite (ALOS) SAR images covering Dongkemadi glacier located on the Tibetan Plateau, China. An experiment with real data showed that the proposed method could obtain glacial flow patterns efficiently, and that the difference between two-pass DInSAR and the proposed method is a result of DEM bias and glacial thinning. The approach presented in this letter proved to be appropriate for monitoring glacial motion and provides a valuable tool for glacier studies, without the need of an external DEM.  相似文献   
996.
997.
998.
BACKGROUND: The aim of this study was to examine the significance of ultrasound-measured carotid intima-media thickness (CIMT) in high-risk patients with hypertension and coronary artery disease (CAD), as an independent prognostic factor in determining the risk of all-cause death or future cardiovascular events. METHODS: The study included 297 consecutive patients (mean age +/- SD, 57 +/- 9.4 years) with diagnosed hypertension and CAD, referred for coronary angiography. The mean of maximal CIMT in two arterial segments bilaterally was calculated. The primary endpoint was a patient's death from all causes. Death, stroke, or myocardial infarction comprised the secondary, composite endpoint. RESULTS: There was a follow-up of 1 to 79 (mean, 41) months. The predictors of death in a multivariate Cox proportional hazards model were the number of stenosed coronary arteries (P = .007) and CIMT (P = .001). The risk of the secondary, composite endpoint (death, stroke, or myocardial infarction) was determined by diabetes (P = .008) and CIMT (P = .010). Nearly 99% of patients with "low CIMT" (< or =1.13 mm) survived for 5 years, versus 78% with "high CIMT" >1.13 mm (log-rank test; P < .001). For the secondary, composite endpoint (death, stroke, or myocardial infarction), the event-free survival rate was 95% (low CIMT), versus 74% after 5 years (high CIMT) (P < .008). CONCLUSIONS: Intima-media thickness of the carotid arteries is a strong and independent predictor of death and serious cardiovascular events in hypertensive patients with CAD referred for coronary angiography.  相似文献   
999.

Introduction

Peripheral nerve disruptions, frequently occurring during limb injuries, give rise to serious complications of patients recovery resulting from limitations in neural tissue regeneration capabilities. To overcome this problem bridging techniques utilizing guidance channels gain their importance. Biodegradable polymeric tubes seem to be more prospective then non-degradable materials – no necessity of implant removal and possibilities of release of incorporated drugs or biologically active agents that may support nerve regeneration process are the main advantages.

Material and methods

Polymer blend of commercial poly(L-lactic acid) (PLLA) and in-house synthesized poly(trimethylene carbonate) (PTMC) were processed in an organic solvent – phase inversion process on a supporting rod – to form a guidance porous tube of 1.1 mm inner diameter. In vivo experiments on rat''s cut femoral nerve by using either the tubes or end-to-end suturing (control group) involved 22 and 19 rats, respectively. Motor recovery of operated limbs, neuroma occurrence and histopathology of explanted nerves were evaluated after 30, 60 and 90 days of implantation.

Results

Motor recovery of the limbs was of similar rate for the two animal groups. The neuroma formation was evident in over 90% control specimens, while for the bridging group it was less than 40% of all evaluable samples (p = 0.0022). Biocompatibility of applied materials was affirmed by moderate tissue response.

Conclusions

Application of the biodegradable PLLA/PTMC polymeric tubes effectively supports regeneration of discontinued nerves. The applied material prevents neuroma formation, by reducing the scar tissue formation time and, thus, accelerating the process of neural tissue restoration.  相似文献   
1000.
The propagation rate constant, kp, was determined for the polymerization of (phenoxymethyl)oxirane (2,3-epoxypropyl phenyl ether) initiated by potassium tert-butoxide in the presence of various crown ethers: 12-crown-4, 15-crown-5, 18-crown-6, dicyclothexano-18-crown-6, dicyclohexano-24-crown-8, dibenzo-18-crown-6 and dibenzo-24-crown-8. The equation correlating kp with complexation constants, Kc, of the crown ethers was derived.  相似文献   
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