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21.
The present investigation was aimed at studying the possible role of curcumin against N-nitrosodiethylamine (NDEA)-induced toxicity in albino rats. Administration of NDEA to rats at a concentration of 0.1 mg/ml in drinking water ad libitum for 21 days produced toxicity in them, which was evident from histopathological changes in the rat livers, and increased levels of blood serum enzyme markers, i.e. aspartate transaminase, alanine transaminase, alkaline phosphatase, and lactate dehydrogenase. In addition, the levels of oxidative stress markers like lipid peroxidation (LPO), protein carbonyl (PCC), and glutathione-S-transferase (GST) activity were elevated and the total glutathione (GSH) content was reduced in the livers. The administration of curcumin to rats at concentrations of 10, 20, and 40 mg/ml in drinking water along with 0.1 mg/ml of NDEA for 21 days effectively suppressed NDEA-induced toxicity and also resulted in a dose-dependent reduction in the levels of blood serum enzyme markers (AST, ALT, ALP, and LDH). Moreover, LPO, PCC, and GST activity were reduced and the GSH level was increased upon the administration of curcumin along with NDEA. The results obtained for the comet assay in rat hepatocytes and blood lymphocytes showed a significant dose-dependent decrease in the mean tail length. The micronucleus assay performed on rat hepatocytes also showed a dose-dependent reduction in the frequency of micronucleated cells along with curcumin administration. These results suggest that curcumin has a protective role against NDEA-induced toxicity in albino rats.  相似文献   
22.
Effective communication between clinicians, patients, and families at end of life is associated with better clinical outcomes. A large body of literature describes the key skills needed for effective communication. We believe that clinicians could also benefit from communication skills more commonly associated with business or law negotiations. We will demonstrate via analogy (i.e. buying a house) how four key business/law negotiation techniques – 1. Determine your Reservation and Aspiration Value; 2. Separate People from their Positions; 3. Separate Positions from Interests; and 4. Logrolling of Interests – can be applied to a difficult family meeting in a home hospice patient.  相似文献   
23.
Pulmonary hypertension of the newborn (PHN) constitutes a critical condition with severe cardiovascular and neurological consequences. One of its main causes is hypoxia during gestation, and thus, it is a public health concern in populations living above 2500 m. Although some mechanisms are recognized, the pathophysiological facts that lead to PHN are not fully understood, which explains the lack of an effective treatment. Oxidative stress is one of the proposed mechanisms inducing pulmonary vascular dysfunction and PHN. Therefore, we assessed whether melatonin, a potent antioxidant, improves pulmonary vascular function. Twelve newborn sheep were gestated, born, and raised at 3600 meters. At 3 days old, lambs were catheterized and daily cardiovascular measurements were recorded. Lambs were divided into two groups, one received daily vehicle as control and another received daily melatonin (1 mg/kg/d), for 8 days. At 11 days old, lung tissue and small pulmonary arteries (SPA) were collected. Melatonin decreased pulmonary pressure and resistance for the first 3 days of treatment. Further, melatonin significantly improved the vasodilator function of SPA, enhancing the endothelial‐ and muscular‐dependent pathways. This was associated with an enhanced nitric oxide‐dependent and nitric oxide independent vasodilator components and with increased nitric oxide bioavailability in lung tissue. Further, melatonin reduced the pulmonary oxidative stress markers and increased enzymatic and nonenzymatic antioxidant capacity. Finally, these effects were associated with an increase of lumen diameter and a mild decrease in the wall of the pulmonary arteries. These outcomes support the use of melatonin as an adjuvant in the treatment for PHN.  相似文献   
24.
Objective: To evaluate the long-term clinical effect of high-intensity focussed ultrasound (HIFU) as a non-invasive modality for ablation of abdominal wall endometriosis (AWE) foci.

Methods: All women who were diagnosed with cutaneous endometriosis and underwent HIFU ablation and 4-year follow-up were included. Patient symptoms, imaging performed, HIFU ablation, recurrence, lesion location, size and number were collected and analyzed.

Results: A total of 51 women with 57 painful abdominal wall masses with a median volume of 4.00?cm3 and a mean age of 30.5±2.12 years were treated with HIFU. The main symptoms were a palpable painful abdominal mass (93%), protrusion of the skin (28.1%, 16) or lack of protrusion of the skin (71.9%, 41). Ultrasound was initially performed in 100% (51) of women, whereas 6% (3) required MRI examinations to distinguish the features and range of the masses. Ablation was performed with a median 300?s of sonication time, 40?min treatment time, 150?W of power and 41800?J of total energy to treat lesions that were a median volume of 3.83?cm3. No severe complications occurred, except in one patient with a first-degree skin burn, during the 48-month follow-up period. The pooled recurrence of cutaneous endometriosis occurred in 3.9% (2) of women.

Conclusion: The diagnosis of AWE should be confirmed with imaging of the lesion number, location, size and features before HIFU ablation. HIFU should be the first choice for the treatment of AWE as it is a non-invasive method, with high efficiency and safety and rapid postoperative recovery.  相似文献   

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Attachment is a behavioral and physiological system, which enables individual’s dynamic adaptation to its environment. Attachment develops in close interaction between an infant and his/her mother, plays an important role in the development of the infant’s brain, and influences the quality of interpersonal relationships throughout life.Security of attachment is believed to influence individual response to stress, exposing insecurely organized individuals to deregulated autonomic nervous system and exaggerated hypothalamic-pituitary-adrenal activity, which, in turn, produces increased and prolonged exposure to stress-hormones. Such stress responses may have considerable implications for the development of diverse health-risk conditions, such as insulin resistance and hyperlipidemia, shown by numerous studies.Although the mechanisms are not yet fully understood, there is compelling evidence highlighting the role of psychological stress in the development of type 1 diabetes (T1D). One of the possible contributing factors for the development of T1D may be the influence of attachment security on individual stress reactivity. Thus, the suggestion is that insecurely attached individuals are more prone to experience increased and prolonged influence of stress hormones and other mechanisms causing pancreatic beta-cell destruction.The present paper opens with a short overview of the field of attachment in children, the principal attachment classifications and their historic development, describes the influence of attachment security on individual stress-reactivity and the role of the latter in the development of T1D. Following is a review of recent literature on the attachment in patients with T1D with a conclusion of a proposed role of attachment organization in the etiology of T1D.  相似文献   
28.
Breast elastography has been available for more than 15 years but is not widely incorporated into clinical practice. Many publications report extremely high accuracy for various breast elastographic techniques. However, results in the literature are extremely variable. This variability is most likely due to variations in technique, a relatively steep learning curve, and variability in methods between vendors. This article describes our protocol for performing breast elastography using both strain elastography and shear wave elastography, which produces high sensitivity and specificity. Additionally, we will describe the most commonly known false-positive and false-negative lesions as well as how to detect them.  相似文献   
29.
The aim of this paper is to present a method to produce macroporous thin membranes made of poly (ethyl acrylate-co-hydroxyethyl acrylate) copolymer network with varying cross-linking density for cell transplantation and prosthesis fabrication. The manufacture process is based on template techniques and anisotropic pore collapse. Pore collapse was produced by swelling the membrane in acetone and subsequently drying and changing the solvent by water to produce 100 microns thick porous membranes. These very thin membranes are porous enough to hold cells to be transplanted to the organism or to be colonized by ingrowth from neighboring tissues in the organism, and they present sufficient tearing stress to be sutured with surgical thread. The obtained pore morphology was observed by Scanning Electron Microscope, and confocal laser microscopy. Mechanical properties were characterized by stress–strain experiments in tension and tearing strength measurements. Morphology and mechanical properties were related to the different initial thickness of the scaffold and the cross-linking density of the polymer network. Seeding efficiency and proliferation of mesenchymal stem cells inside the pore structure were determined at 2 h, 1, 7, 14 and 21 days from seeding.  相似文献   
30.
目的探讨脂肪抽吸与腹壁成形术联合进行腹壁体形重塑的临床疗效,总结手术成功与减少并发症的经验。方法对18例腹部脂肪堆积伴腹壁皮肤松弛的患者采用肿胀麻醉,负压吸引器行腹壁脂肪抽吸;做耻骨联合上W形切口,折叠缝合腹直肌前鞘,切除多余皮瓣后分层缝合腹壁。结果所有切口均Ⅰ期愈合,随访4~24个月,腹部平坦,切口瘢痕不明显,腹围平均缩小15 cm,外形满意。结论根据患者腹部皮肤、皮下脂肪、腹壁肌肉等多方面的情况,有针对性的采用脂肪抽吸与腹壁整形相结合的腹壁体形重塑术,能够获得满意的效果,手术方法安全可靠。  相似文献   
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