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51.
Normal human keratinocytes and the keratinocyte-derived cell lines NCTC 2544 and A 431, were exposed for different periods (1-5 days) to various concentrations (0.023-46.6 micrograms/ml) of nickel (Ni2+). A dose- and time-dependent inhibition of cell growth and viability was observed. Cultures exposed to 2.3 micrograms Ni2+/ml showed approximately 50% cell survival at 5 days. An increase in release of interleukin 1 by keratinocytes was detected following culture for 24 h with a Ni2+ concentration of 2.3-11.5 micrograms/ml. Short periods of incubation (30 min) with these concentrations induced an activation of lipoxygenase in leucocytes from healthy subjects, without modifying cell viability. The results suggest that the percutaneous penetration of small amounts of Ni2+ can result in damage to keratinocytes and can initiate sensitization.  相似文献   
52.
The endocrine pancreas of a corticosteroid-treated infant during the course of nephrotic syndrome was morphologically studied. Islet cell hyperplasia and dispersed endocrine cell aggregates between acinar tissue were observed. A marked numerical increase of B cells was identified by using cytochemical and immunofluorescent methods. Morphometric data support the morphological observations. The findings suggest that corticosteroid treatment induces endocrine cell replication and neogenesis.  相似文献   
53.
Abstract. We report the case history of a child with congenital adrenal hyperplasia which was complicated by recurrent hypoglycaemic episodes during common infections. There are few reports in literature on the association of hypoglycaemia and congenital adrenal hyperplasia. In accordance with others, we believe that hypoglycaemic attacks in adrenal hyperplasia are perhaps more frequent than recorded in literature.  相似文献   
54.
Active Heymann nephritis is an organ-specific autoimmune disease of the rat kidney, characterized by the formation of immune complexes located subepithelially in the glomerulus. The T cell-mediated humoral immune response is directed to gp330, a large renal epithelial glycoprotein which is expressed both in the proximal tubule and on glomerular podocytes. In this study polyclonal rabbit antibodies raised against affinity-purified rat gp330 were used to screen a λ-gt11 expression library of the rat kidney. One cDNA clone that was recognized by the antibodies coded for a 2.7-kb protein that is not described in the sequence database of GenBank/EMBL. Two other groups of cDNA clones were identified that displayed similarity with several members of the low-density lipoprotein (LDL)-receptor gene family to which gp330 belongs. By comparison with the gp330-cDNA sequence, these two clones could be mapped to two remote areas on the extracellular domain of gp330. The antigenicity of these two areas is in accordance with their location in highly hydrophilic regions on the extracellular domain of gp330. The cDNA clones described in this study may represent two main immunodominant regions on rat gp330.  相似文献   
55.
The recent advances in the psychoneuroimmunology have suggested that the hematopoiesis may be under a neuroendocrine regulation, mainly exerted by the pineal gland. In particular, melatonin (MLT), which is the main pineal hormone, has appeared to stimulate platelet generation, probably by promoting the megakaryocyte fragmentation and modulating the cytokine network involved in platelet production. On this basis, we have evaluated the effect of pharmacological doses of MLT on platelet number in patients with persistent thrombocytopenia due to different causes. The study included 200 patients, who were randomized to receive supportive care alone or MLT at 20 mg/day orally in the evening, for al least 1 month. No MLT-related toxicity occured. Platelet mean number rapidly and significantly increased in response to MLT, and a normalization of platelet number was achieved on MLT therapy in 71/98 (72%) patients. The least responsive form of thrombocytopenia was DIC. This study shows that the pineal hormone MLT may represent a well tolerable and effective therapy of thrombocytopenia due to different pathogenetic mechanisms.  相似文献   
56.
When performing epicardial ablation of ventricular tachycardia (VT), caution must be taken not to damage the coronary arteries. We report a case in which a new, nonfluoroscopic technique for incorporating an accurate, real‐time reconstruction of the main coronary vessels into a three‐dimensional electroanatomic map was used for epicardial VT ablation.  相似文献   
57.
Incomplete Endothelialization of Left Atrial Appendage . We describe the case of a 74‐year‐old man with Rendu Osler Weber syndrome affected by permanent atrial fibrillation, who underwent percutaneous placement of a 24‐mm Watchman left atrial appendage system. After anticoagulation therapy dismissal, he had a transient ischemic attack (TIA). Therefore he underwent surgical removal of the device, ablation of atrial fibrillation with Maze IV procedure and biatrial reduction. Very interestingly, no significant endothelialization of the device was observed 10 months after implantation. In conclusion, this case is important because, to our knowledge, it is the first finding of Watchman device with lack of endothelialization. (J Cardiovasc Electrophysiol, Vol. 23, pp. 1384‐1385, December 2012)  相似文献   
58.
Background: Several studies have illustrated the safety and the procedural outcome of high‐frequency vibrational energy in guidewire refractory chronic total occlusions (CTOs). Aim: To evaluate the advantage of high‐frequency vibrational energy device (CROSSER Catheter) use in coronary complex CTO revascularization as primary strategy. Methods: CROSSER was used as a primary approach if four or more unfavorable angiographic features were observed in the CTO lesions. Results: From May 2007 to February 2009, a CTO percutaneous intervention attempt was performed in 178 lesions of 171 patients (60.1 ± 8.9 age with 49.4 ± 7.2% in ejection fraction). Among these, the CROSSER was used in 46 complex CTO lesions of 45 patients (25.8% of cases) and in the remaining cases, typical CTO percutaneous coronary intervention techniques were employed. Clinical success was 84.8% in CROSSER group. Moreover, in the CROSSER group, no periprocedural myocardial infarction, perforation, or 30 days MACE was observed. In addition, the use of CROSSER was associated with lower time of procedure, time of fluoroscopy, and contrast load administration as compared with conventional techniques [88 ± 27 minutes vs 109 ± 38 minutes (P = 0.045), 39 ± 12 minutes vs 50 ± 27 minutes (P = 0.032), and 334 ± 122cc vs 408 ± 198cc (P = 0.05), respectively]. Conclusion: In the present study, the CROSSER System was safe and obtained a high rate of success in complex CTO similar to conventional dedicated guidewire techniques for noncomplex CTO; however, the CROSSER Catheter obtained CTO recanalization with lower contrast load administration, less time of procedure, and lower fluoroscopy exposure. (J Interven Cardiol 2010;23:130‐138)  相似文献   
59.
We described a 77‐year‐old patient, previously implanted with a dual‐chamber pacemaker later upgraded to a cardiac resynchronization therapy‐defibrillator (CRT‐D) device with an active‐fixation coronary sinus pacing lead, who underwent a transvenous mechanical extraction procedure for a device‐related systemic infection. All leads were removed successfully with a transvenous approach. With regard to the coronary sinus (CS) lead (Attain 4195 StarFix, Medtronic Inc., Minneapolis, MN, USA), manual traction was ineffective and extraction required long and challenging mechanical dilatation up to distal CS using either conventional sheaths or modified CS lead delivery. (PACE 2010; 34:e66–e69)  相似文献   
60.
Summary. Background: The aim of the current study was to perform two separate meta‐analyses of available studies comparing low‐molecular‐weight heparins (LMWHs) vs. unfractionated heparin (UFH) in ST‐elevation myocardial infarction (STEMI) patients treated (i) with primary percutaneous coronary intervention (pPCI) or (ii) with PCI after thrombolysis. Methods: All‐cause mortality was the pre‐specified primary endpoint and major bleeding complications were recorded as the secondary endpoints. Relative risk (RR) with a 95% confidence interval (CI) and absolute risk reduction (ARR) were chosen as the effect measure. Results: Ten studies comprising 16 286 patients were included. The median follow‐up was 2 months for the primary endpoint. Among LMWHs, enoxaparin was the compound most frequently used. In the pPCI group, LMWHs were associated with a reduction in mortality [RR (95% CI) = 0.51 (0.41–0.64), P < 0.001, ARR = 3%] and major bleeding [RR (95% CI) = 0.68 (0.49–0.94), P = 0.02, ARR = 2.0%] as compared with UFH. Conversely, no clear evidence of benefits with LWMHs was observed in the PCI group after thrombolysis. Meta‐regression showed that patients with a higher baseline risk had greater benefits from LMWHs (r = 0.72, P = 0.02). Conclusions: LMWHs were associated with greater efficacy and safety than UFH in STEMI patients treated with pPCI, with a significant relationship between risk profile and clinical benefits. Based on this meta‐analysis, LMWHs may be considered as a preferred anticoagulant among STEMI patients undergoing pPCI.  相似文献   
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