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1.
Estrus in a 10-yr-old brown hyena was described by monitoring urinary steroid metabolites. These studies were repeated the succeeding year and combined with ultrasonography, vaginal cytology, and laparoscopy to further aid in identifying natural and induced estrus. Collection of semen from a 14-yr-old male brown hyena was accomplished by electroejaculation. Use of frozen semen once during natural estrus and again during estrus induced with follicle stimulating hormone (FSH) did not result in pregnancy. Further studies with this animal indicate that stimulation with gonadotropin releasing hormone (GNRH), rather than FSH, may be the more appropriate treatment for stimulating ovulation in canids or related species. While this study did not result in conception, a significant step toward that end was realized by utilizing urinary estrogen to monitor the estrus cycle.  相似文献   
2.
Thirty-five patients (23 males) with asymptomatic hyperuricemia for at least two years underwent two-dimensioal ultrasonography of knees and ankles. Urate deposits (tophi) in tendons, synovium, and other soft tissues were detected in 12 patients (34%). Increased vascularity (inflammation) was evident in 8 of these patients (23%). Tophi were more frequently found in knees than in ankles and were especially prevalent in the distal patellar tendon. The presence of tophi was unrelated to the known duration of hyperuricemia (mean, 5 years). Ultrasonography allows detection of tophi and inflammation in a third and in a fourth, respectively, of asymptomatic hyperuricemic patients.  相似文献   
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The beef industry has emphasized the improvement of feed utilization, as measured by modeling feed intake through performance traits to calculate residual feed intake (RFI). Evidence supports an inverse relationship between feed efficiency and reproductive function. The objective of this study was to determine the relationship of reproductive assessments and RFI unadjusted (RFIKoch) or adjusted for body composition (RFIus) and the relationship among fertility-related parameters. In total, 34 crossbred bulls were housed together for 112 days of performance evaluation, followed by assessment of scrotum IR imaging, scrotal circumference, testes ultrasonography and semen quality parameters at 377±33.4 days of age. Bulls were slaughtered at 389±34.0 days of age, and analyses of carcass composition, biometrics and histomorphometry of the testis and epididymis were conducted. Bulls were grouped into two subpopulations based on divergence of RFI, and within each RFI model either by including 50% of the population (Halves, high and low RFI, n=17) or 20.6% extremes of the population (Tails, high and low RFI, n=7). The means of productive performance and fertility-related measures were compared through these categories. Pearson’s correlation was calculated among fertility-related measures. In the Halves subpopulation of the RFIus, sperm of low-RFI bulls had decreased progressive motility (47.30% v. 59.90%) and higher abundance of tail abnormalities (4.30% v. 1.80%) than that of high-RFI bulls. In the Tails subpopulation of the RFIKoch, low RFI displayed less variation in the scrotum surface temperature (0.62°C v. 1.16°C), decreased testis echogenicity (175.50 v 198.00 pixels) and larger (60.90 v. 56.80 mm2) but less-developed seminiferous tubules than high-RFI bulls. The evaluation of fertility-related parameters indicated that a higher percentage of immature seminiferous tubules was correlated with occurrence of sperm with distal droplets (r=0.59), a larger temperature variation at the top of the scrotum was correlated with improved sperm progressive motility (r=0.38), a lower occurrence of sperm loose head abnormalities was correlated with larger temperature variation at the lower part of the scrotum (r=−0.43), and a lower minimum testis echogenicity (r=−0.59) and smaller scrotal circumference (r=0.72) were correlated with age. The adjustment for body composition (RFI determination) enabled distinct biological inferences about reproduction and feed efficiency when compared with the non-adjusted model. However, both RFI models and the correlation analysis supported the hypothesis that feed-efficient bulls have features of delayed sexual maturity. Overall, the assessment of fertility-related measurements is important to avoid the improvement of feed efficiency at the expense of reproductive function in young bulls.  相似文献   
5.
目的:探讨超声内镜(EUS)辅助下内镜黏膜下切除术(EMR)对食管癌前病变患者肿瘤标志物及应激反应指标的影响。方法:选择山东大学齐鲁医院青岛院区消化内科于2016年3月至2018年4月期间收治的食管癌前病变患者137例,采用随机数字表法将患者分为常规组(n=68,常规胃镜下行EMR)和EUS组(n=69,EUS辅助下行EMR),比较两组患者临床指标,比较两组术前、术后血清肿瘤标志物及应激反应指标水平,比较两组术前、术后1周相关遗传学分子水平。结果:EUS组手术时间、术后流质饮食时间均短于常规组(P0.05),并发食管黏膜小穿孔例数、使用钛夹止血例数均少于常规组(P0.05)。两组患者术后肿瘤特异性生长因子(TSGF)、细胞角蛋白19血清片段21-1(CYFRA21-1)、鳞状上皮细胞癌抗原(SCC-Ag)均较术前升高,但EUS组低于常规组(P0.05)。两组患者术后肾上腺素(E)、去甲肾上腺素(NE)、肾素(R)、血管紧张素Ⅱ(AngⅡ)、醛固酮均较术前升高,但EUS组低于常规组(P0.05)。两组患者术后1周细胞周期素E(Cyclin E)、转化生长因子-α(TGF-α)均较术前降低,且EUS组低于常规组(P0.05)。结论:相比于常规胃镜,经EUS辅助下EMR治疗食管癌前病变可有效改善患者的临床指标,减轻患者应激反应,有利于降低血清肿瘤标志物及遗传学分子水平。  相似文献   
6.
目的:探讨肺脏超声对新生儿呼吸窘迫综合征(NRDS)的诊断价值,并分析肺超声评分的临床应用价值。方法:本研究选择2017年5月至2018年5月于我院确诊的NRDS患儿45例作为观察组,选择同期于我院就诊的非肺病患儿45例作为对照组,所有患儿均行肺脏超声检查。分析NRDS患儿肺脏超声特征性征象,比较肺脏超声对两组患儿各种征象的检出率,分析肺脏超声对NRDS的诊断价值,比较两组肺超声评分。结果:NRDS患儿全部存在肺实质征象,超声下肺组织回声呈肝样伴支气管充气征,轻度的NRDS患儿于肺脏超声下表现为局灶性的肺实质,且支气管充气征不明显;重度的NRDS患儿于肺脏超声下表现为肺实质范围的进一步扩大,且支气管充气征随病情的加重而愈发明显。观察组肺实质、胸膜线异常、A线消失、弥漫性肺水肿、支气管充气征等征象的检出率显著高于对照组(P0.05),两组B线存在征象的检出率比较无统计学差异(P0.05)。肺实质、胸膜线异常和A线消失三种特征征象同时存在时对NRDS诊断的灵敏度和特异性均为100.00%,肺实质、胸膜线异常和支气管充气征三种特征征象同时存在时对NRDS诊断的灵敏度为80.00%,特异性为100.00%。观察组双肺、左肺、右肺、双侧肺、双肺底肺超声评分均高于对照组(P0.05)。结论:肺脏超声对NRDS的诊断价值较高,且肺超声评分可以评估NRDS患儿的病情严重程度,有助于指导患儿的治疗。  相似文献   
7.
Capuchin monkey (Cebus apella) is a new world primate that in recent years has become important in biomedical research. The purpose of this study was to establish and correlate normal fetal growth parameters with gestational age in capuchin monkeys. In seven pregnant animals serial ultrasonic assessment of gestational sac (GS), embryo/fetal greatest length (GL), biparietal diameter (BPD), thorax height (TH), and femur length (FL) were performed. Identification of the GS was possible on day 23+/-2.8 (X +/- SE). The embryo and its heartbeat was detected on day 32.7+/-2.8, the GL being measurable thereafter. By day 45.4+/-1.4 BPD and TH were measurable. FL could only be measured from day 70.6+/-2.1. Predictive regression equations of gestational age (GA) were modeled with data obtained. In addition, preliminary data of fetal heart rate showed a decrease in frequency with advancing gestation.  相似文献   
8.
This study was conducted to determine if correlations exist between the numbers of microscopic follicles comprising ovarian follicular reserve (OFR) and antral follicle counts (AFCs), and to assess the usefulness of computerized analyses of ovarian ultrasonograms and magnetic resonance (MR) images for estimating OFR in excised porcine, ovine and bovine ovaries. As a pre-requisite to these analyses, we characterized and compared ovarian cortical histomorhpology and follicle populations in the three species varying in prolificacy and overall reproductive longevity, and hence the total number of microscopic and antral follicles. Ultrasonographic and MR images were obtained at the scanner settings optimized to provide opposing contrasts between antral follicles and the ovarian stroma. Commercially available ImageProPlus® analytical software was used to calculate numerical pixel values (NPVs) and pixel heterogeneity (standard deviation of the pixel values) along the computer-generated lines (4–6) placed in the area corresponding to the ovarian cortex. The numbers of primordial (r = 0.38, P < 0.01) and intermediate follicles (r = 0.37, P < 0.01) were correlated with the numbers of antral follicles in bovine ovarian sections. The numbers of primordial (r = 0.28, P < 0.05), intermediate (r = 0.31, P < 0.01) and primary follicles (r = 0.27, P < 0.05) correlated directly with mean NPVs of the ultrasonographic ovarian images in cattle. There was a negative correlation between primary follicle numbers and NPVs of MR images (3D FAST-SPOILED GRADIENT ECHO) of the porcine ovarian cortex (r = −0.31, P < 0.05). To summarize, the numbers of primordial and intermediate follicles could only be estimated from AFCs in cows. Using ultrasound NPVs, the numbers of primordial, intermediate and primary follicles could be directly estimated in bovine ovaries and the quantitative image attributes of MR images were useful for quantifying porcine primary follicles. The bovine ovarian model is compatible with human situation and hence future studies should be undertaken to ascertain the usefulness of AFCs and ultrasonographic image analyses for estimating OFR in women.  相似文献   
9.
Ultrasonography is a fast, accurate, and non–invasive method to determine the sex of cod ( Gadus morhua ). In this study it was used on 788 farmed cod ranging in age from 1 to 6 yr. Accuracy of sex determination was over 95% for fish subjected to Ultrasonography from October to April.  相似文献   
10.
This article is about new reproductive technologies, maternal anxieties, and existential uncertainties. It explores the question of why pregnant women in Vietnam's capital, Hanoi, have become avid consumers of obstetrical ultrasound scanning even while expressing profound doubts regarding the reliability and safety of this new technology of pregnancy. Through a phenomenological analysis of the social production of women's sense of reproductive risks and uncertainties, the article shows how Hanoian women's paradoxical stances toward ultrasound imaging can be explained through a consideration of embodied and historically generated experiences within everyday local worlds. The article argues that the "scientific stories" of fetal well-being and normality that are produced through ultrasonography are challenged by vivid and continual exchanges in everyday lives of stories of the inherent uncertainties of existence in general and of human reproduction in particular.  相似文献   
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