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31.
Objective Hypercoagulability is a commonly described complication in patients with Cushing’s syndrome. Recent clinical studies have indicated various abnormalities of coagulation and fibrinolysis parameters which may be related to that phenomenon. The aim of this study was to investigate the mechanisms underlying the hypercoagulable state in patients with Cushing’s syndrome. Research methods and procedures A wide range of serum markers involved in the processes of blood coagulation and fibrinolysis was measured in a group of 33 patients with Cushing’s syndrome and 31 healthy controls. No participant was taking medication which could influence the result or had known diseases, except hypertension and diabetes, which could affect blood coagulation or fibrinolysis parameters. Results Patients with Cushing’s syndrome had higher levels of clotting factors II (P = 0.003), V (P < 0.001), VIII (P < 0.001), IX (P < 0.001), XI (P < 0.001) and XII (P = 0.019), protein C (P < 0.001), protein S (P < 0.001), C1-inhibitor (P < 0.001) and plasminogen activator inhibitor-1 (PAI-1) (P = 0.004). The activity of fibrinolytic markers, plasminogen (P < 0.001), antithrombin (P < 0.001) and antithrombin antigen (P = 0.001) was also increased in the patient group. Conclusion The study has demonstrated hypercoagulability in patients with Cushing’s syndrome manifest as increased prothrombotic activity and compensatory activation of the fibrinolytic system. We propose the introduction of thromboprophylaxis in the preoperative and early postoperative periods, combined with a close follow-up in order to prevent possible thromboembolic events in patients with Cushing’s syndrome.  相似文献   
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Contamination and health risk hazards of organophosphorus pesticides residues in vegetables were studied. Ethyl-chlorpyrifos, observed at an average level of 0.211 ± 0.010 mg kg−1 in 42% of tomato, 0.096 ± 0.035 mg kg−1 in 10% of eggplant and 0.021 ± 0.013 mg kg−1 in 16% of pepper was below the 0.5 mg kg−1 MRL. Dichlorvos was the most frequently detected residue in all the samples analyzed. Levels of malathion in tomatoes (0.120 ± 0.101 mg kg−1) and pepper (0.143 ± 0.042 mg kg−1) exceeded the MRL of 0.1 mg kg−1. Health risks were found to be associated with methyl-chlorpyrifos, ethyl-chlorpyrifos, and omethioate in tomatoes and methyl-chlorpyrifos, ethyl-chlorpyrifos, dichlorvos, monocrotophos and omethioate in eggplant. Routine monitoring of these pollutants in food items is required to prevent, control and reduce the pollution and to minimize health risks.  相似文献   
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BACKGROUND: There is increasing use of hormone replacement therapy (HRT) by post-menopausal women. Observational epidemiological studies have shown reductions in cardiovascular risk factors in HRT users in the USA, but no randomized controlled trials of HRT have been carried out in the primary practice setting. Previous studies of cardiovascular risk factors have shown a variety of responses according to type of progestagen and oral or topical administration. None has examined the effect of route using an identical progestagen. OBJECTIVES: Our aim was to establish differences, if any, in alteration in cardiovascular risk factors with HRT in post-menopausal women according to route of administration of HRT, oral, transdermal and implant, using first oestrogen alone then oestrogen plus norethisterone, or testosterone for implant. METHODS: Subjects were recruited by letter of invitation to women aged 50-65 years from lists in general practices local to the Charing Cross Hospital Lipid Clinic in West London. Their menopausal status was confirmed and they were randomized to one of three treatment groups or acted as controls. They attended for three visits; at baseline, HRT was initiated as oestrogen alone, oral or transdermal. At the 3-month visit, HRT with the progestagen, norethisterone, was given cyclically, continuously or transdermally until the final visit at 6 months. A separate group of women from the menopause clinic at Chelsea and Westminster Hospital were studied on oestrogen implant then on implanted oestrogen and testosterone. The outcome measures studied were the separate effects of the four regimes as compared with controls on lipoproteins, glucose, insulin, fibrinogen, factor VII and E-selectin, together with weight, waist:hip ratio and blood pressure. RESULTS: The continuous combined oestrogen-progestagen therapy had similar effects on cardiovascular risk factors as oestrogen with cyclical progestagen. All regimes lowered low-density lipoprotein cholesterol, the oral route being more potent than the parenteral; the effect of transdermal HRT was similar to the implant. Lp(a) was reduced only with the oral route. Reductions in factor VII and E-selectin were observed in both the oral and transdermal routes. There was no increase in body mass index, waist:hip ratio, blood pressure or glucose and insulin levels with any of the HRT regimes used. Systolic blood pressure was reduced with the transdermal route. CONCLUSIONS: This study supports the evidence that oestrogen-progestagen HRT, both oral and transdermal, although attenuating some of the benefit of oestrogen alone on fibrinogen and high-density lipoprotein, significantly reduces cardiovascular risk factors, which should diminish post-menopausal risk of coronary disease.  相似文献   
35.
BACKGROUND: Autoimmune hepatitis is a chronic inflamatory disease of the liver of unknown etiology, characterized by the loss of tolerance against hepatic tissue, leading to the destruction of hepatic parenchyma. It predominantly affects females, and rarely occurs in the same family. CASE REPORT: In this paper we presented brother and sister with autoimmune hepatitis according to the criteria of the International Autoimmune Hepatitis Group. CONCLUSION: Because of a possible genetic predisposition to autoimmune hepatitis, the occurrence of the disease in a family member suggested the need to examine other family members.  相似文献   
36.
BACKGROUND: Postoperative recurrence of the liver hydatid disease befalls approximately 10-30% of patients. Preoperative or postoperative therapy with albendazole in single therapeutic protocol (800 mg/d, within 28 days) indicated the need to evaluate the hydatid cyst liquid protoscoleces viability. Morphological changes of protoscoleces following the treatment with drugs are not well known. AIM: To estimate the viability of protoscoleces after preoperative or postoperative albendazole therapy, and their ability for cystic metamorphosis. METHODS: A prospective, randomized clinical trial included 30 patients with liver hydatid disease, treated with albendazole and surgically (I group), and 30 patients in the control group treated only surgically (II group). The concentration of albendazole and its active metabolite albendazole sulphoxide in the cysts contents were determined using HPLC. Estimation of protoscoleces viability was based on the established micromorphologic criteria, and compared between the patients treated with albendazole, and the patients treated only surgically. Biological assessment of the viability was performed on protoscoleces with uncertain signs of the disturbed viability (unchanged structure, evaginated, without movements) using intraperitoneal injection of 1 ml of protoscoleces prepared suspension to AO type of rats. RESULTS: The concentration of albendazole in cysts' contents ranged from 0 to 64.9 microg/ml, and of its active metabolite from 0.5 to 40.8 microg/ml. The presence of fully viabile protoscoleces in the albendazol treated patients was significantly lower than in the control group. A significant difference was noticed in the presence of disintegrated protoscoleces without movements in the albendazol treated group, compared to the control group. Biological assessment of the viability showed incapability of these protoscoleces for cystic metamorphoses. CONCLUSION: Low viability of parasites due to medicamentous therapy is very useful and important to surgeons, because the fertility of cysts is lower, and the risk of the disease recurrence is reduced.  相似文献   
37.
BACKGROUND: To present a female patient who lived 5 years after total pelvic exenteration (TPE). CASE REPORT: The female patient underwent TPE due to retrovesicovaginal fistula as a consequence of locoregional irradiation after the operation for the malignoma of the vaginal part of the uterus. In the formation of Bricker conduit, the ureter antireflux was achieved by the application of the "tobacco sack muff" made of the intestines around the ureter. By the use of this technique, the occurrence of pyelonephritis, as the leading cause of death in such patients, was prevented. CONCLUSION: TPE is a hope for significantly prolonged survival of patients with advanced pelvic malignomas, or with a postirradiatiation fistula.  相似文献   
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The dose distribution in small lung tumors (coin lesions) is affected by the combined effects of reduced attenuation of photons and extended range of electrons in lung. The increased range of electrons in low-density tissues can lead to loss of field flatness and increased penumbra width, especially at high energies. The EGSNRC Monte Carlo code, together with DOSXYZNRC, a three-dimensional voxel dose calculation module has been used to study the characteristics of the penumbra in the region of the target-lung interfaces for various radiation beam energies, lung densities, target-field edge distances, target size, and depth. The Monte Carlo model was validated by film measurements made in acrylic (simulating a tumor) imbedded in cork (simulating the lung). Beam profiles that are deemed to be acceptable are defined as those in which no point within the planning target volume (target volume plus 1 cm margin) received less than 95% of the dose prescribed to the center of the target. For parallel opposed beams and 2 cm cube target size, 6 MV photons produce superior dose distribution with respect to penumbra at the lateral, anterior, and posterior surfaces and midplane of the simulated target, with a target-field edge distance of 2.5 cm. A lesser target-field edge distance of 2.0 cm is required for 4 MV photons to produce acceptable dose distribution. To achieve equivalent dose distribution with 10 and 18 MV photons, a target-field edge distance of 3.0 and 3.5 cm, respectaively, is required. For a simulated target size of 4 cm cube, a target-field edge distance of 2, 2.5, and 3 cm is required for 6, 10, and 18 MV photons, respectively, to yield acceptable PTV coverage. The effect, which is predominant in determining the target dose, depends on the beam energy, target-field edge distance, lung density, and the depth and size of the target.  相似文献   
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