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21.
AIM: The article focuses on the radioprotective effect of acute hypoxia on healthy tissues during preoperative accelerated hypoxyradiotherapy of colorectal carcinoma performed as locoregional irradiation including the common iliac lymph nodes. Analysis of early and late side effects and complications. PATIENTS AND METHODS: In this prospective study, early and late complications were assessed in 50 patients as a function of hypoxyradiotherapeutic dose increase. The preliminary treatment results of this radiotherapeutic modification were evaluated after a median follow-up of 48 months using Kaplen-Meier analysis. Between April 1991 and February 1997, 50 patients (36 men and 14 women) with colorectal carcinoma were treated preoperatively with locoregional accelerated hypofractionated hypoxyradiotherapy. The extent of disease was classified according to Dukes' criteria (A: four patients, B. 28 patients, C: 18 patients). We used a 20-MeV linear accelerator with two parallel opposed fields. Hypoxyradiotherapy was performed extending from the perineum to the L4 region. Acute hypoxia was induced during irradiation by ventilation of a hypoxic gas mixture containing 7.8-8.0% oxygen. Total doses of 24 Gy/8 days, 28 Gy/9 days, and 32 Gy/10 days were applied in five, 20, and 25 patients, respectively. Low anterior resection or abdominoperineal amputation of the rectum was performed the day after completion of preoperative hypoxyradiotherapy. The early reactions after irradiation were evaluated according to the Common Toxicity Criteria of the National Cancer Institute (CTC-NCI). RESULTS: Early postirradiation proctitis was documented in three and early radiation-induced cystitis in two patients only. Neither early nor late radiation-associated complications were observed in any of the three hypoxyradiotherapy schedules during the follow-up period of 6-105 months. Based on Kaplan-Meier analysis (median 48 months), a 5-year overall survival rate of 61.5% and a local relapse-free survival rate of 84.2% can be expected. Treatment failures were predominantly systemic. CONCLUSION: We believe it can be concluded that acute hypoxia has a radioprotective effect on normal tissues during accelerated hypoxyradiotherapy of colorectal carcinoma. Hypoxyradiotherapy permits safe administration of doses higher than those tolerated by normoxic, noncanceorus tissue, resulting in the amplification of the biological effect of radiation on tumor tissue and contributing to an improved outcome after combined radiosurgical treatment of colorectal carcinoma.  相似文献   
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Acyclic nucleoside phosphonates are novel class of clinically broadly used antivirotics effective against replication of both DNA viruses and retroviruses including human immunodeficiency virus (HIV). We have investigated their in vitro effects on immune defence mechanisms in human peripheral blood mononuclear cells, with the main emphasis on expression of cytokines which are able to suppress the entry of HIV in cells. Included in the study were prototype acyclic nucleoside phosphonates, i.e. 9-[2-(phosphonomethoxy)ethyl]adenine (PMEA; adefovir), 9-[2-(phosphonomethoxy)ethyl]-2,6-diaminopurine (PMEDAP), (R)-and (S)-enantiomers of 9-[2-(phosphonomethoxy)propyl]adenine [(R)-PMPA; tenofovir] and [(S)-PMPA], and of 9-[2-(phosphonomethoxy)propyl]-2,6-diaminopurine [(R)-PMPDAP] and [(S)-PMPDAP], and their N(6)-substituted derivatives. Some of the compounds were found to substantially enhance secretion of chemokines such as macrophage inflammatory protein-1alpha (MIP-alpha/CCL3), and "regulated on activation of normal T cell expressed and secreted" (RANTES/CCL5). Secretion of MIP-1beta/CCL4 was only marginally increased, whereas production of interleukin-16 (IL-16) and interferon-gamma (IFN-gamma) remained uninfluenced. The most effective proved to be the N(6)-cyclooctyl-PMEDAP, N(6)-isobutyl-PMEDAP, N(6)-pyrrolidino-PMEDAP, N(6)-cyclopropyl-(R)-PMPDAP, and N(6)-cyclopentyl-(R)-PMPDAP derivatives. Remarkably enhanced secretion of chemokines was reached within 2-4 h of the cell culture, and was observed at concentration of 2-5 microM. It may be suggested that acyclic nucleoside phosphonates represent a new generation of antivirotics with combined antimetabolic and therapeutically prospective immunostimulatory properties.  相似文献   
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ObjectivesThe aim of the study was to analyze polymorphisms of receptor for advanced glycation end products (RAGE) gene, and glyoxalase I gene and soluble RAGE, sRAGE, in physiological and pathological pregnancy.Design and methodsPolymorphisms of RAGE gene (? 429 T/C, ? 374 T/A, 557 G/A, 2184 A/G) and glyoxalase I gene (A419C) and sRAGE serum levels were determined in 284 women with pathological and physiological pregnancy.ResultsNo differences in distribution of genotype and allelic frequencies of studied polymorphisms were found. GA genotype of RAGE 557 G/A polymorphism (known as Gly82Ser) is associated with lower sRAGE serum levels in healthy pregnant women compared to GG genotype (483 ± 104 vs. 692 ± 262 pg/mL, p = 0.008). sRAGE correlates negatively with ALT in patients with pregnancy intrahepatic cholestasis (r = ? 0.536, p = 0.05).ConclusionsWe did not show any association of RAGE and glyoxalase I gene polymorphisms with pathological pregnancy, however further studies are needed to confirm the results.  相似文献   
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The numerical simulation of the Korotkoff sounds is realized by a 14 segment hemodynamic model of the cardiovascular system developed in the Institute of Thermomechanics, Czech Academy of Sciences. The cardiovascular system is modeled by four segments of the pulsating heart and by 10 vascular segments of pulmonary and systemic circuits connected with the heart in series. To better understand the generation of Korotkoff sounds the systemic arterial flow is studied in detail by a distributed parameter model. The analysis of self-excited oscillations in a collapsible tube (i.e., the systemic artery) is based on a one-dimensional model where the effect of expected flow separation is replaced by the change of viscous friction along the tube.  相似文献   
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BackgroundChronic thromboembolic pulmonary hypertension (CTEPH) is a rare, but due to its unfavorable prognosis, feared complication of thromboembolic disease. We assessed the incidence and risk factors for pulmonary hypertension (PH) in a cohort of consecutive patients admitted with pulmonary embolism to the tertiary University Hospital.MethodsIn our cohort of 120 consecutive patients with proved pulmonary embolism (PE) we studied the course of biochemical and echocardiographic parameters with regard to risk factors predicting pulmonary hypertension at the end of hospitalization.ResultsEchocardiographic signs of pulmonary hypertension were present at the time of discharge in more than one half (50.8%) of patients admitted with pulmonary embolism. Predictors of persisting pulmonary hypertension were initial pulmonary hypertension, high initial NT-proBNP levels and age.ConclusionResidual pulmonary hypertension at discharge was present in 50.8% cases, at this time there was a strong relationship between PH and elevated NT-proBNP on admission. The patients will be followed-up and possible development of CTPEH will be evaluated at 6, 12 and 24-month period.  相似文献   
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Autoimmune pancreatitis (AIP) type 1 is commonly associated with simultaneous involvement of extrapancreatic organs. Sclerosing cholangitis, sialadenitis, retroperitoneal fibrosis, Sjögren syndrome, and other extrapancreatic lesions are often observed concurrently with AIP. High levels of immunoglobulin G4 (IgG4) in the blood serum and affected tissues are typical of this diagnostic entity. We describe a case report of a 58-year-old female with findings of AIP (according to Asian criteria), IgG4-positive mastitis, and histologically verified Mikulicz syndrome. The effect of corticoid therapy supported the diagnosis of AIP and simultaneously led to the eradication of recurrent mastitis. To the best of our knowledge, this is the first reported case of concurrent findings of AIP and IgG4 mastitis. Our case report supports the concept of systemic IgG4 syndrome with multisystem involvement. Timely diagnosis and appropriate therapy can be effective in a high percentage of patients.  相似文献   
29.
Twins were diagnosed by ultrasound in a 29-year-old woman. The cesarean delivery revealed at first a mature girl with a large benign sacrococcygeal teratoma and then a healthy boy. X-ray and CT examinations of the teratoma showed pelvic and lower limb bones. A mature teratoma-tridermona (weight 475 g) containing the underdeveloped lower half of a human body was confirmed during surgery and verified morphologically. The fraternal twins, i.e., the girl operated upon and her brother, have been followed for 5 years and are without any complaints. They have normal neurological function.Presented at the XVIII Annual Meeting of the International Society for Pediatric Neurosurgery, Paris 1990  相似文献   
30.
This article reviewed smoking related systemic diseases and oral diseases. Smoking is related to lung cancer, cardiovascular diseases and many other systemic diseases. Cigarette smoke affects the oral cavity first, so it is evident that smoking has many negative influences on oral cavity, for example, staining of teeth and dental restorations, wound healing, reduction of the ability to smell and taste, and development of oral diseases such as oral cancer, periodontitis, smoker's palate, smoker's melanosis, hairy tongue, leukoplakia, oral candidiasis and implant survival rate. The article also discusses the relationship between smoking and dental caries in detail.  相似文献   
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