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1.
Recent studies have shown that Salmonella shedding status affects sows’ microbiota during gestation and that these modifications are reflected in the faecal microbiota of their piglets at weaning. The aims of this study were: (a) to evaluate the persistence, up to the fattening period, of the previously measured link between the microbiota of piglets and their mothers’ Salmonella shedding status; and (b) measure the impact of the measured microbiota variations on their Salmonella excretion at this stage. To achieve this, 76 piglets born from 19 sows for which the faecal microbiota was previously documented, were selected in a multisite production system. The faecal matter of these swine was sampled after 4 weeks, at the fattening stage. The Salmonella shedding status and faecal microbiota of these animals were described using bacteriological and 16S rRNA gene amplicon sequencing respectively. The piglet digestive microbiota association with the Salmonella shedding status of their sows did not persist after weaning and did not affect the risk of Salmonella excretion during fattening, while the birth mother still affected the microbiota of the swine at fattening. This supports the interest in sows as a target for potentially transferrable microbiota modifications.  相似文献   
2.
Classic polycystic ovary syndrome (PCOS) is a high-risk phenotype accompanied by increased risks of reproductive and metabolic abnormalities; however, the local metabolism characteristics of the ovaries and their effects on germ cell development are unclear. The present study used targeted metabolomics to detect alterations in the intermediate metabolites of follicular fluid from classic PCOS patients, and the results indicated that hyperandrogenism but not obesity induced the changed intermediate metabolites in classic PCOS patients. Regarding the direct contact, we identified mitochondrial function, redox potential, and oxidative stress in cumulus cells which were necessary to support oocyte growth before fertilization, and suggested dysfunction of mitochondria, imbalanced redox potential, and increased oxidative stress in cumulus cells of classic PCOS patients. Follicular fluid intermediary metabolic profiles provide signatures of classic PCOS ovary local metabolism and establish a close link with mitochondria dysfunction of cumulus cells, highlighting the role of metabolic signal and mitochondrial cross talk involved in the pathogenesis of classic PCOS.  相似文献   
3.
BackgroundPregnant women are among the key groups in iodine nutrition evaluation. The purpose of the present study was to summarize the evidence supporting the relationship between mild iodine deficiency (UIC: 100–150 μg/L) in pregnant women and levels of thyroid function tests.MethodsThis review follows the guidelines for systematic reviews (PRISMA 2020). Three electronic databases (PubMed, Medline, and Embase) were searched for relevant publications in English on the association between mild iodine deficiency in pregnant women and thyroid function. Articles published in Chinese were searched in China’s electronic databases (CNKI, WanFang, CBM, and WeiPu). Pooled effects were presented as standardized mean differences (SMDs) and odds ratios (ORs) with 95% confidence intervals (CIs) using fixed or random effect models, respectively. This meta-analysis was registered at www.crd.york.ac.uk/prospero as CRD42019128120.ResultsWe summarized the results from 7 articles with 8261 participants. The overall pooled results showed that the levels of FT3, FT4, and abnormal TgAb (the antibody levels exceeded the upper limit of the reference range) were significantly increased in pregnant women with mild iodine deficiency compared to pregnant women with adequate iodine status (FT3: SMD=0.854, 95% CI: 0.188, 1.520; FT4: SMD=0.550, 95% CI: 0.050, 1.051; TgAb: OR=1.292, 95% CI: 1.095; 1.524). Subgroup analysis was carried out on the sample size, ethnicity, country, and gestation of FT3, FT4, and TSH, but no plausible factor was found. Egger’s tests indicated no publication bias.The increase in FT3 and FT4, as well as TgAb levels, in pregnant women is associated with mild iodine deficiency.ConclusionMild iodine deficiency is associated with an increase in FT3,FT4 and TgAb levels in pregnant women. Mild iodine deficiency may increase the risk of thyroid dysfunction in pregnant women.  相似文献   
4.
目的:探讨同型半胱氨酸(homocysteine,HCY)摄入后对孕鼠糖代谢的影响以及生物学机制分析。方法:孕鼠妊娠10 d后,将实验动物随机分为3组,每组12只,妊娠对照组(Ctrl)腹腔注射生理盐水,同型半胱氨酸高剂量组(HCYH)和同型半胱氨酸低剂量组(HCYL)腹腔注射HCY溶液,注射浓度分别为200 mg/kg·d和100 mg/kg·d,持续20 d(即为HCY20 d)后,利用血糖含量检测试剂盒和胰岛素试剂盒分别检测孕鼠空腹血糖水平、胰岛素水平;葡萄糖检测试剂盒对孕鼠葡萄糖耐量和胰岛素抵抗进行检测;蛋白免疫印迹法检测孕鼠目的蛋白过氧化物酶体增殖物激活受体γ(PPARγ)、葡萄糖转运蛋白4(GLUT4)、蛋白激酶B(AKT)、磷酸化AKT蛋白(P-AKT)的表达。结果:与Ctrl组比较,在孕鼠注射HCY后,空腹血糖水平升高、血清中胰岛素浓度下降、HOMA-β指数下降、HOMA-IR指数升高(P<0.05);摄入葡萄糖后,孕鼠血糖随时间的变化而下降,葡萄糖曲线下面积升高(P<0.05);摄入胰岛素后,孕鼠血糖随时间的变化而升高,胰岛素曲线下面积升高(P<0.05);PPARγ、P-AKT、GLUT4蛋白表达水平下降,HCYH组降低水平更为显著(P<0.05)。结论:孕鼠HCY摄入后,生物体糖代谢紊乱,AKT磷酸化表达水平抑制,HCY可能通过降低PPARγ的表达减少AKT磷酸化,导致胰岛素受体的活化,进而激活了PI3K/AKT通路,减少了脂肪组织中的GLUT4表达,增加了对于葡萄糖的摄取能力。  相似文献   
5.
目的观察凝结芽孢杆菌活菌片(商品名:爽舒宝)预防先兆流产保胎妇女胃肠功能紊乱的临床疗效。方法将60例先兆流产保胎妇女随机分为爽舒宝预防组和对照组,预防组30例,对照组30例,两组均给予常规服用保胎药物,出现顽固性便秘后用开塞露通便,其中预防组在此基础上同时口服凝结芽孢杆菌活菌片首次2. 1 g,以后1.05 g/次,3次/d,温水送服,疗程2-4周。观察保胎期间孕妇胃肠功能紊乱情况和使用开塞露的通便次数。结果预防组患者胃肠功能紊乱的发生率显著低于对照组,差异有统计学意义(P〈0.05 )。结论凝结芽孢杆菌活菌片预防先兆流产保胎妇女胃肠功能紊乱疗效显著,值得临床推广。  相似文献   
6.
A total of 50 mixed parity sows of a high-prolificacy genetic line were used to evaluate the impact of feed restriction during lactation on their production and reproductive performance and their performance in the subsequent lactation. From day 7 of lactation, sows were distributed according to a completely randomized experimental design into two treatments. In treatment 1, sows were fed 8.0 kg feed/day (control) and in treatment 2, sows were fed 4.0 kg/day. The same suckling pressure was maintained until weaning on day 28 of lactation. Average minimum and maximum temperatures measured during the experimental period were 32.1°C and 16.5°C, respectively. Control sows presented significantly higher feed intake (P<0.001) compared with the restricted sows (6.43 v. 4.14 kg/day, respectively). Treatments influenced BW and backfat thickness losses (P<0.001). Control sows lost less BW than the restricted-fed sows (7.8 v. 28.2 kg). Restricted-fed sows lost more backfat thickness than those in the control group (3.97 v. 2.07 mm; P<0.01). Restricted-fed sows tended (P<0.10) to be lighter at weaning compared with the control sows (211 v. 227 kg). The composition of BW loss was influenced by the treatments (P<0.001), as the restricted-fed sows lost more body protein, lipids and energy compared with the control sows (3.90 v. 0.98 kg, 11.78 v. 4.83 kg and 584 v. 224 MJ, respectively). Litter weight gain was greater (P<0.05) in control sows than in restricted-fed sows (2.70 v. 2.43 kg/day). Daily milk production was 19% higher (P<0.01) in the control sows compared with the restricted-fed sows (8.33 v. 6.99 kg/day). However, restricted-fed sows presented a higher (P<0.05) lactation efficiency than the sows of the control group (82.30% v. 72.93%). No differences were detected (P>0.10) in weaning-to-estrus interval and averaged 4.3 days. No effect of the treatment (P>0.10) was observed on any of the studied performance traits in the subsequent lactation, except for litter size at birth that tended (15.2 v. 14.1; P<0.10) to be lower for the restricted sows. In conclusion, the present study demonstrated that feed restriction during lactation leads to intense catabolism of the body tissues of sows, negatively affecting their milk production, and the litter weight gain and possibly number of piglets born in the next litter. On the other hand, restricted-fed sows are more efficient, producing more milk per amount of feed intake.  相似文献   
7.
To investigate the effect of uterine space on timing of embryonic mortality, multiparous sows were left intact (CTR; n=42) or subjected to unilateral oviduct ligation (LIG; n=23), after their first post wean oestrus. Intact sows were killed at day 9 (n=10), day 21 (n=15), or day 35 (n=17), and LIG sows were killed at day 21 (n=11) or day 35 (n=12) of gestation. At day 9, 92% of ovulations were represented by an embryo. At day 21, embryonic mortality was 24% and was not altered by increasing uterine space. At day 35, space per embryo was twice as large in LIG sows (30±3 v. 16±0.8 cm), and implantation length tended to be larger (19.0±1.2 v. 15.5±1.3 cm). Between day 21 and day 35, CTR sows lost another 8% to 14% of their embryos, whereas LIG sows lost none. Embryos tended to be heavier (4.9±0.2 v. 4.3±0.3 g) in LIG sows. In conclusion, embryonic loss in multiparous sows is 24% by day 21 and is not related to space, whereas after day 21 limited space causes additional 8% to 14% embryonic mortality in intact sows only.  相似文献   
8.
目的:应用实时荧光定量PCR(RT-PCR)技术对不同孕周孕妇外周血浆胎盘特异性基因4(PLAC4)m RNA基因进行检测,寻找唐氏综合征产前诊断的可靠生物学标志物,为无创性产前诊断提供新的突破口。方法:按入组标准随机选取健康育龄未妊娠女性5例,正常健康妊娠孕妇60例(早期妊娠20例、中期妊娠20例、晚期妊娠20例),唐氏筛查高危孕妇8例,正常分娩24 h女性5例。共收集外周血浆样本78例。应用RT-PCR技术,检测样本中的PLAC4 m RNA基因含量,并进行相对定量分析。结果:健康育龄未妊娠女性及正常分娩后24 h女性外周血浆中均无游离胎儿PLAC4 m RNA基因的存在;正常健康妊娠孕妇不同孕周标本均检测到PLAC4 m RNA基因,以早期妊娠作为对照,中期妊娠是早期妊娠的1.99倍,晚期妊娠是早期妊娠的3.73倍;唐氏筛查高危孕妇均检出PLAC4 m RNA基因,含量是早期妊娠的6.36倍。结论:PLAC4 m RNA基因有望成为唐氏综合征产前诊断的可靠性生物学标志物。  相似文献   
9.
10.
Changes in physical body size during gestation were monitored using 529 sets of sow measurements. All sows were from the same herd and production system with a range in parity from 1 to 8. Sows were individually weighed, P2 backfat thickness was determined by ultrasound and morphometric measurements of body size were taken five times during gestation: day 0 (at service), day 25, day 50, day 80 and day 110. The morphometric measurements included sow height (from floor to last rib at the midline, from floor to ventral surface and from floor to hip), heart girth, depth of last rib, length (from snout to tail and from anterior scapula to tail) and width (at ham, at last rib and at shoulder). Regression analyses were used to model the relationship between day of gestation or parity number and morphometric measurements of body size. Regression equations were also developed to estimate sow weight from physical measurements, day of gestation and parity. As expected, sow dimensions, in general, increased as pregnancy progressed and also with increasing parity number. The relationships between day of gestation and body dimensions were described by linear and quadratic regression models, which had a range of adjusted R2 values up to 0.99. Similar relationships to parity number had a range of R2 values between 0.51 and 0.96. Sow depth, which can be used as an estimate of the width of the sow when lying, equalled the maximum width of the gestation stall (650 mm) at day 103 of gestation. However, by day 40 of gestation, predicted mean sow depth (570 mm) equalled the width at the rear of the crate. The implication of this is that after day 40 of gestation, the average sow was too wide for the rear of the crate when lying in a recumbent position. On day 110 of gestation, 95% of the mean sow body depths would be accommodated in stalls that were 674 mm wide; however, the range in body sizes with increasing parity number suggests the use of more than one stall width would be appropriate. Sow weight could be estimated with an adjusted R2 value of 0.81 and with a residual standard deviation (r.s.d.) of 16.5 kg using heart girth alone, or more accurately using a model with parity, day of gestation, P2 backfat depth and heart girth as the parameters (R2 = 0.89, r.s.d. 12.4 kg).  相似文献   
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