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排序方式: 共有5215条查询结果,搜索用时 125 毫秒
81.
S. Aghaei H. Nikzad M. Taghizadeh A. A. Tameh A. Taherian A. Moravveji 《Andrologia》2014,46(8):927-935
Cancer treatment with cyclophosphamide (CP) may result in reproductive toxicity as one of its side effects. The pumpkin seed is a rich natural source of antioxidant. We have assessed the possible protective efficacy of pumpkin seed extract on sperm characteristics, biochemical parameters and epididymal histology of CP‐treated rats. Male adult Wistar rats were categorised into four groups. Group 1 served as control and received intraperitoneal (IP) injection of isotonic saline solution. Group 2 rats were treated with CP by IP injection in a single dose of 100 mg/kg body weight, only once. Group 3 and 4 received CP plus 300 and 600 mg/kg pumpkin seed extract respectively. Six weeks after treatment, sperm characteristics, biochemical parameters and histopathological changes were examined. Results showed that, sperm characteristics in CP‐treated rats were significantly decreased. Biochemical analysis results showed that the co‐administration of 300 mg pumpkin seed extract could increase the total antioxidant capacity (TAC) level significantly. In CP‐treated rats, histopathological changes such as vacuolisation, disorganisation and separation of epididymal epithelium were observed as well. Interestingly, pumpkin seed extract could improve the above‐mentioned parameters remarkably in CP‐treated rats. Our findings indicated that pumpkin seed extract might be used as protective agent against CP‐induced reproductive toxicity. 相似文献
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The present study aimed to assess the radiological parameters from gamma rays due to the uncontrolled disposal of porcelain waste to the environment. Qualitative and quantitative identification of radionuclides in the investigated samples was carried out by means of a high-purity germanium (HPGe) detector. The average activity concentrations of the local porcelain samples were measured as 208.28?Bq/kg for 226Ra, 125.73?Bq/kg for 238U, 84.94?Bq/kg for 232Th and 1033.61?Bq/kg for 40K, respectively. The imported samples had an average activity of 240.57?Bq/kg for 226Ra, 135.56?Bq/kg for 238U, 115.74?Bq/kg for 232Th and 1312.49?Bq/kg for 40K, respectively. Radiological parameters and the radium equivalent Raeq for the investigated samples were calculated. The external and internal hazard indices, representative level index (Iγ), alpha index (Iα), and the exemption level (Ix), were estimated to be higher than the recommended value (unity), while the average activity concentrations for the studied samples were higher than recommended levels. In conclusion, we are concerned that disposal of porcelain in the environment might be a significant hazard. 相似文献
85.
《Expert review of anticancer therapy》2013,13(10):1433-1447
Microtubules and their component protein, tubulin, constitute a popular target for the treatment of cancer. Many drugs that are presently used in clinics or in clinical trials and drugs that show promise as anticancer drugs bind to tubulin and microtubules. There are three conventional binding sites on β-tubulin where many of these drugs bind. The binding properties, conformational changes upon binding, association constants and thermodynamic parameters for the drug–tubulin interaction on these three sites are discussed. The antiproliferative activities of these drugs and the possible correlation with the binding properties are also described. 相似文献
86.
Chi-Ting Horng Jon-Kway Huang Hui-Yun Wang Chi-Chang Huang Fu-An Chen 《Nutrients》2014,6(11):5327-5337
Polygonatum alte-lobatum Hayata, a rhizomatous perennial herb, belongs to the Liliaceae family and is endemic to Taiwan. We investigated the antioxidant and anti-fatigue activities of P. alte-lobatum in exercised rats. Levels of polyphenols, flavonoids and polysaccharides and 2,2-diphenyl-1-picrylhydrazyl (DPPH) free-radical scavenging activity were measured in extracts of P. alte-lobatum (EPA). Sprague-Dawley rats were randomly divided into four groups for 8-week treatment with vehicle (control) and low-, medium-, and high-dose EPA (LEPA, MEPA, HEPA; 0, 75, 150, and 375 mg/kg/day, respectively). Exercise performance was evaluated by exhaustive treadmill exercise time and by changes in body composition and biochemical variables at the end of the experiment. EPA contained polyphenols, flavonoids and polysaccharides, with polysaccharide content at least 26 times greater than that of polyphenols and flavonoids. Trend analysis revealed that EPA dose-dependently scavenged DPPH free radicals. EPA treatment dose-dependently increased endurance running time to exhaustion and superoxide dismutase activity and total antioxidant ability of blood. EPA dose-dependently decreased serum urea nitrogen and malondialdehyde levels after exercise. Hepatic glycogen content, an important energy source for exercise, was significantly increased with EPA treatment. EPA could be a potential agent with an anti-fatigue pharmacological function. 相似文献
87.
Eli D. Scher Inaya Ahmed Ning J. Yue Salma K. Jabbour 《Journal of gastrointestinal oncology.》2014,5(3):198-211
Historically treated with surgery, current practice recommends anal carcinoma to be treated with a combination of chemotherapy and radiation. This review will examine the anatomy, modes of disease spread and recurrence, and evaluate the existing evidence for treatment options for these tumors. An in-depth examination of specific radiation therapy (RT) techniques—such as conventional 3D-conformal RT and intensity-modulated RT—will be discussed along with modern dose constraints. RT field arrangement, patient setup, and recommended gross and clinical target volume (CTV) contours will be considered. Areas in need of further investigation, such as the role in treatment for positron emission tomography (PET) will be explored. 相似文献
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目的动态观察Zephyr5826起搏器心房自动阈值管理(ACM)功能的开启情况、准确性及安全性。方法选取置入Zephyr5826起搏器患者68例,于置入术后第1,7天及1,2,3,6个月时随访程控,观察ACM功能的开启情况,手工测试心房起搏阈值并与ACM功能测定的值进行比较。结果 68例均完成随访。随访期内35例(51.50%)成功开启ACM功能,其中术后第1,7天及1,2,3个月时开启例数分别为14例(20.6%)、21例(30.9%)、26例(38.2%)、28例(41.2%)和32例(47.1%)。手工测试与ACM测试的心房阈值无差异。33例因起搏器自动测定心房刺激除极波(ER)过小不推荐开启ACM功能。随访期间心电图及动态心电图(Holter)均未见心房失夺获及感知不良。与普通电压和高电压起搏相比,自动阈值管理功能在心房输出方面分别节省50%,88%的能量消耗。结论 Zephyr5826起搏器ACM功能可以安全有效的应用低能量起搏心脏。部分患者术后因起搏器测定心房ER过小未能开启ACM功能,但在随访过程中ACM的开启比例逐渐升高。 相似文献
90.
《International journal of audiology》2013,52(5):384-394
The behaviour of 95 clinically normal 6-month-old babies previously studied as neonates and as 6-week-old infants was video-recorded while they were presented with sound stimuli. The stimulus series varied in sound pressure level (SPL) (30 and 60 dB), band width (BW) and rise time (RT), and included two voice signals and a no-sound (control) trial. Video-records were made both for the whole body aspect and for a 31/2 'close-up' of the head. Later, the video-records were shown to 6 observers who were allowed to see the babies for 13 s at each trial. The first 5 s was a pre-stimulus observation period, and the second 8 s usually contained a sound stimulus. Between the trials, the observers were given 20 s in which to record pre-stimulus activity, confidence in response, and movement details. Data for movement details are not reported here. Different segments of the baby's body were observed on different occasions as detailed in our previous reportsThe confidence ratings for response to tonal stimuli were analysed using aspects of signal detection theory for differences amongst various body segments (n.s.), SPL (p < 0.001), BW (p < 0.05), and RT (p < 0.01). A 60-dB broad-spectrum noise band (BSN) and the 2 voices were by far the most effective stimuli. They elicited detectabilities which differed between segments. The response to different sound stimuli was affected by the baby's pre-stimulus activity state. The results are discussed in relation to our previous studies 相似文献