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121.
目的:观察苦参注射液对慢性乙型肝炎性肝硬化的临床效果及其作用机制.方法将58例慢性乙型肝炎性肝硬化患者随机分为观察组和对照组,在一般支持治疗的基础上,观察组加用苦参注射液,治疗8周后,比较两组肝功能、肝纤维化指标.结果观察组肝功能改善显著,肝纤维化减轻,与对照组比较差异均有统计学意义(P〈0.05).结论在正常治疗基础上加用苦参注射液,有助于肝炎性肝硬化患者的肝功能恢复,有较好的临床效果.其作用机制可能是通过影响外周单核细胞IL-10表达、调节机体促炎抗炎平衡而实现的. 相似文献
122.
123.
通过试验,分析得出羊口蹄疫、羊小反刍兽疫、羊痘疫苗在不同日龄段的羊只上,以不同免疫注射组合方式进行接种,产生的免疫抗体效果及免疫安全性实验,为基层从事羊免疫工作的动物防疫员提供科学依据。 相似文献
124.
利用分离的奶牛X精子冷冻精液生产体内性控胚胎试验 总被引:6,自引:0,他引:6
采用常规精液和分离的X精子冷冻精液对115头超数排卵的青年和经产荷斯坦母牛人工输精生产体内性控胚胎。结果表明,利用2支和3支性控精液给超排青年母牛输精,头均分别获得6.8枚±4.8枚和6.3枚±3.2枚可用胚胎,与常规精液的超排效果(7.2枚±5.2枚)无明显差异;利用2支和3支性控精液给超排经产母牛输精,头均可用胚胎分别为7.5枚±4.5枚和8.6枚±5.6枚,与常规精液的超排效果(6.1枚±3.2枚)相比,分别增加23%(P>0.05)和41%(P>0.05),无显著差异,但解冻后性控精子会明显影响经产母牛的受精率;对用性控精液输精生产的12枚抽样胚胎采用LAMP法进行性别鉴定并移植,结果获得了91.7%的雌性率和36.4%的受胎率。结果提示,X精子的分离过程会在一定程度上影响受精率,用分离的X精子冷冻精液对超排母牛进行人工授精生产体内性控胚胎是可行的。 相似文献
125.
Takahiro AYA Yukiko TOMIOKA Takashi TAKEUCHI 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2021,83(7):1144
The effect of lactoferrin (LF) on embryo development was investigated by using lipopolysaccharide (LPS)-treated mouse sperm. For the development rate of the 2-cell stage embryo, the embryo derived from LPS- and LF-treated sperm showed similar survival rate to the control embryo. On day 12 after the embryo transfer into the recipient, the frequent abnormality was observed in the embryo derived from LPS-treated sperm, and the abnormality was tended to be inhibited in the embryo derived from LPS- and LF-treated sperm. These results imply that LF treatment on sperm contaminated with bacteria may facilitate the embryo development, which contribute to the improvement of infertility. 相似文献
126.
The plasma membrane from spermatozoa of rainbow trout was isolated by four techniques: sonication, hypotonic shock, mechanical homogenization after freeze-thawing, and nitrogen cavitation, in combination with continuous sucrose gradient centrifugation. Nitrogen cavitation (900 PSI, 20 min equilibration at 4°C) was the most effective technique.Following nitrogen cavitation, four bands were recovered in the sucrose gradient at densities 1.03, 1.05, 1.09 and 1.15 g/ml. Electron microscopy revealed membrane vesicles of various sizes in bands 1 to 3, while enzyme analysis revealed a 3.9 to 5.5-fold enrichment in 5'-nucleotidase and little contamination by lactate dehydrogenase (cytosol) and succinic dehydrogenase (mitochondria). Lipid analysis of bands 1 and 2 indicated a 6 to 7-fold enrichment in cholesterol and a cholesterol: phospholipid ratio of 0.59–0.70. Seven classes of phospholipids were present in bands 1–3 with no significant differences observed among bands. These data indicate that the vesicles (in bands 1 and 2) obtained after nitrogen cavitation are primarily plasma membranes. Membranes in band 3 appear to be slightly contaminated with nuclear membranes.Most of the plasma membrane proteins were acidic to neutral. The 2 main membrane proteins were 42 and 30 Kilodaltons. 相似文献
127.
Sayyed Mohammad Hadi Alavi Elham Jorfi Azadeh Hatef Sayyed Abdul Saheb Mortezavi 《Aquaculture Research》2010,41(10):e688-e694
Spermatozoa concentration, ionic composition, osmolality, glucose and total protein contents of seminal plasma and sperm motility were determined in Barbus sharpeyi (Cyprinidae, Teleosotei). Spermatozoa concentration ranged from 9.77 to 20.20 × 109 spermatozoa mL?1. Osmolality (mOsmol kg?1) and ionic contents (mM L?1) of the seminal plasma were 274.5±9.0, 70.0±3.4 Na+, 28.8±0.9 K+, 101.7±3.1 Cl?, 0.9±0.1 Mg2+ and 2.1±0.1 Ca2+ respectively. Total protein and glucose were 5.3±0.2 g L?1 and 76.7±4.3 mM L?1 respectively. Sperm motility was initiated in a hypo‐osmotic condition, composed of either an ionic (KCl or NaCl) or a non‐ionic (sucrose) activation medium. Duration of sperm motility was very short: <2 min after activation in distilled water. Percentage of motile spermatozoa was significantly higher in an activation medium containing NaCl compared with that of distilled water. An activating medium containing NaCl or KCl higher than 150 mM or sucrose higher than 275 mM totally inhibited the activation of sperm motility. Immediately after sperm activation, wave(s) propagated along the flagellum, but waves were restricted to the proximal part of the flagellum (close to the head) at 1 min post activation. Studied characteristics in the present study were compared with those of other cyprinids for understanding inter‐species differences. 相似文献
128.
Ana Eguiguren Enrico Pirotta Kristina Boerder Maurício Cantor Godfrey Merlen Hal Whitehead 《水产资源保护:海洋与淡水生态系统》2021,31(6):1466-1481
- Sperm whales have occupied the waters off the Galápagos Islands, Ecuador, for at least the past 200 years. During the 19th century, they were the target of intensive whaling that severely depleted the population. In recent times, after commercial whaling ended, sperm whales in the region remain vulnerable to multiple threats, especially potential entanglement in fishing gear, which may hinder their ability to recover from the whaling era.
- As a highly mobile, long-lived species, long-term analysis of the habitat use of sperm whales is necessary to establish effective conservation and management strategies. Here, contemporary (1985–2014) and historical (1830–1850) sperm whale habitat use off the Galápagos Islands was analysed and contrasted to the extent of the Galápagos Marine Reserve (GMR). Contemporary habitat use and its variability over time were modelled as a function of geographic, oceanographic, and topographic variables using generalized additive models.
- The fine-scale habitat (<50 km) used by sperm whales was associated with topographic (i.e. depth and slope) and oceanographic characteristics (i.e. relative sea surface temperature and standard deviation of sea surface temperature), but these preferences varied over time.
- While historical and contemporary data indicate that sperm whale habitat primarily occurred within the boundaries of the GMR, in recent years, whales were found up to 30.1% of the time outside the GMR, potentially overlapping with commercial fisheries operating in the area.
- The dynamic nature of the relationship of this nomadic species with its habitat highlights the need of large-scale conservation efforts across the Eastern Tropical Pacific region, including the wide-scale enforcement of regulations requiring the use of Automatic Identification System in fishing vessels, the promotion of on-board fisheries observer programmes, the development of adaptive management strategies, and international collaboration to identify and mitigate threats.
129.
Alternative sources of lipoproteins in semen extenders could replace animal by-products. We hypothesized that: (1) post-thaw semen parameters and fertility would not be different in coconut water (CW)–treated samples compared with egg yolk (EY)–treated samples and (2) the use of an oxygen scavenger (Oxyrase) would improve post-thaw sperm motility and membrane integrity and decrease lipid peroxidation. Experiment 1: three ejaculates each from five stallions were split into four treatments: EY, CW, egg yolk with Oxyrase, and coconut water with Oxyrase. Computer-assisted sperm analysis measured progressive and total motility, velocity, and linearity. Membrane integrity, apoptosis, and lipid peroxidation were evaluated using propidium iodide, annexin, and BODIPY fluorescent probes, respectively. Samples were cryopreserved, stored in liquid nitrogen, and then thawed to 37°C and analyzed again. Experiment 2: one ejaculate was divided into two aliquots and cryopreserved using either CW or EY. In a crossover design, 12 mares were bred on two consecutive cycles with either EY or CW. Pregnancy evaluations were at 14-day gestation. No differences were detected in sperm parameters between CW and EY (P > .05). Oxyrase did not improve sperm motility parameters in post-thaw samples, nor did it show protective effects for viability or against membrane damage (P > .05). More mares became pregnant using CW than EY (11/12 vs. 6/12, respectively; P = .013). Use of CW is a viable alternative to animal-based products in the cryopreservation of stallion semen. 相似文献
130.
In order to establish the determination method of ivermectin (IVM) in the ivermectin microemulsion injection by high performance liquid chromatography (HPLC), Hypersil ODS2 colunm (5 μm,4.6 mm×250 mm) was used in this study. The mobile phase composed of methanol, acetonitrile and water (35:60:5,V/V/V) at a flow rate of 1 mL/min. The detection wave length was set at 244 nm and the column temperature was 30 ℃. The results showed that the HPLC system suitability of IVM was good. A good linear correlation of IVM was observed within the concentration range 80 to 320 μg/mL, and the average recovery rate was 101.90%±2.94% with RSD was 2.88%, the regression equation was Y=22 700X+2 510 (R2=0.9998). The RSD of IVM content in ivermectin microemulsion injection was 1.86%. The method was accurate and reliable,reproducible,easy to operate, which could be used in new type of ivermectin microemulsion injection. The method could be used as the basis of quality control and establishing a quality standard, and to provide basis for quality evaluation, also can provide reliable reference for safe veterinary clinical application in the future. 相似文献