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排序方式: 共有417条查询结果,搜索用时 31 毫秒
41.
The aim of this study was to determine the prevalence and risk factors for subclinical endometritis (SE) and its effects on fertility in repeat breeder dairy cows. Dairy cows of parity 1 to 5 that were artificially inseminated (AI) 3 or more times (selected cows were artificially inseminated an average of 3.9 times) were examined at 190 ± 40 days in milk, and clinically normal cows (n = 77) were selected based on the absence of abnormal discharges on external inspection and the absence of abnormal findings on transrectal palpation and ultrasonographic examination. Endometrial samples were collected from the uterus by using the lavage technique in the luteal phase of the estrus cycle. Collected samples were centrifuged and a drop of sediment was streaked on to a clean microscopic slide and stained with Giemsa. The percentage of polymorphonuclear cells (neutrophils) was counted for each specimen. The analysed data showed that the average amount of neutrophils was 3.1% (0-9) in the selected cows. Abnormal calving (dystocia, twin births, and abortion), retained placenta, and postpartum uterine infections were associated with an increase in prevalence of SE. Subsequently, SE was significantly associated with a decrease in conception rate in the next AI. Conception rate in the next AI was 5% for cows (n = 38) with SE (≥ 3% neutrophil), and 47% for cows (n = 34) without SE (< 3% neutrophil) (P = 0.001). The prevalence of cytologically diagnosed SE (≥ 3% neutrophil) was 52.7% (n = 38). In conclusion, abnormal calving, retained placenta, and postpartum uterine infections may be associated with an increase in prevalence of SE and subsequently, SE may decrease reproductive performance and increase the incidence of repeat breeder syndrome. 相似文献
42.
Wober J Möller F Richter T Unger C Weigt C Jandausch A Zierau O Rettenberger R Kaszkin-Bettag M Vollmer G 《The Journal of steroid biochemistry and molecular biology》2007,107(3-5):191-201
The special extract ERr 731® from the roots of Rheum rhaponticum is the major constituent of Phytoestrol® N which is used for the treatment of climacteric symptoms in menopausal women. However, the molecular mode of action of ERr 731® was unknown. For the first time, ERr 731® and its aglycones trans-rhapontigenin and desoxyrhapontigenin were investigated with regard to the activation of the estrogen receptor- or estrogen receptor-β (ER, ERβ). The related hydroxystilbenes cis-rhapontigenin, resveratrol and piceatannol were studied as comparators. As controls, 17β-estradiol or the selective ER-(propylpyrazoltriol) or ERβ-agonists (diarylpropionitril) were used. Neither in ER-expressing yeast cells, in the ER-responsive Ishikawa cells, nor in human endometrial HEC-1B cells transiently transfected with the ER an activation of ER by ERr 731® or the other single compounds was detected. Furthermore, an antiestrogenic effect was not observed. In contrast in human endometrial HEC-1B cells transiently transfected with the ERβ, 100 ng/ml ERr 731® and the single compounds significantly induced the ERβ-coupled luciferase activity in a range comparable to 10−8 M 17β-estradiol. All effects were abolished with the pure ER antagonist ICI 182780, indicating an ER-specific effect. The ERβ agonistic activity by ERr 731® could be of importance for its clinical use, as central functions relevant to climacteric complaints are proposed to be mediated via ERβ activation. 相似文献
43.
目的:探讨富含半胱氨酸的酸性分泌型蛋白(secreted protien,acidic and rich in cysteine,SPARC)在子宫内膜癌组织中的表达及其临床意义。方法:应用组织芯片技术研究SPARC在正常子宫内膜、增生的子宫内膜和子宫内膜癌组织中的表达情况。结果:SPARC在正常子宫内膜、增生的子宫内膜和子宫内膜癌组织中的阳性表达率分别为96.55%、76.79%、59.50%,差异具有统计学意义(P〈0.05)。在子宫内膜癌中,SPARC的表达强度与手术-病理分期、组织学分级、肌层浸润深度和淋巴结转移相关,差异具有统计学意义(P〈0.05)。结论:SPARC表达的缺失与子宫内膜癌的发生、发展密切相关,检测SPARC可为子宫内膜癌的早期诊断、进一步治疗及预后判断提供一定的理论依据。 相似文献
44.
目的:评价宫腔镜辅助下分段诊刮在子宫内膜癌检查中的临床价值,探讨提高子宫内膜癌诊断准确性的检查方法。方法:选择经分段诊刮诊断为子宫内膜癌患者132例,59例患者分为对照组,术前采取单纯分段诊刮的方式;73例患者分为观察组,术前采取宫腔镜辅助下分段诊刮的方式。根据术后患者病理检查结果,比较两组患者术前诊断的准确性及术中腹腔冲洗液细胞阳性率。结果:观察组检查方式的准确性优于对照组,差异具有统计学意5C(P〈0.05),两组术中腹腔冲洗液细胞阳性病例比较,差异无统计学意义(P〉0.05)。结论:宫腔镜辅助下分段诊刮的方式可提高子宫内膜癌检查的准确性,且不增加肿瘤细胞散播的风险。 相似文献
45.
为探讨枸杞新品系NQ-2纯系种植结实率低的原因,采用TTC法、联苯胺—过氧化氢法、花粉—胚珠比、杂交指数和套袋试验等方法,对NQ-2花粉活力、柱头可授性及繁育系统等进行了研究。结果表明:NQ-2单花花期为3~4 d,花后8 h散粉结束,开花当天花粉活力最高,花粉寿命可持续9 d以上;开花前一天柱头已具可授性,开花第1天柱头可授性最强,开花第3天柱头基本失去可授性;枸杞新品系NQ-2平均花粉-胚珠比8615,OC I=4,结合人工授粉实验结果确定其繁育系统为专性异交。自交不亲和是导致NQ-2纯系种植落花落果结实率低的主要原因。 相似文献
46.
目的:探讨雌激素是否通过AKT途径调控子宫内膜癌KLE细胞中乙二醛酶Ⅰ(GlyoxalaseⅠ,GloⅠ)的表达。方法:采用RT-PCR和Western blotting检测雌激素(17-β雌二醇)处理或AKT途径抑制剂(LY294002)处理子宫内膜癌KLE细胞后GloⅠ的mRNA或蛋白的表达情况。实验分4组:Con组(对照组);LY294002组(LY294002处理组);E2组(17-β雌二醇处理组);E2+LY294002组(LY294002预处理1小时后再17-β雌二醇处理组)。结果:1、经不同浓度的17-β雌二醇(Con、10-11、10-10、10-9M)作用于KLE细胞24小时后,GloⅠmRNA的相对表达量分别为1,1.58±0.04,1.82±0.03,1.81±0.04,以10-10 M的浓度时最为显著(P<0.05)。以10-10 M的17-β雌二醇作用于KLE细胞48小时后,GloⅠ蛋白的相对表达量为1.79±0.02,高于Con组。2、以LY294002抑制AKT途径后,KLE细胞中GloⅠmRNA的相对表达量为0.69±0.03,蛋白的相对表达量为0.16±0.02,均低于Con组。3、E2+LY294002组GloⅠmRNA和蛋白的相对表达量分别为1.02±0.04、1.01±0.03,均低于E2组中GloⅠmRNA和蛋白的相对表达量,E2组分别为1.34±0.03、1.79±0.02。LY294002组GloⅠmRNA和蛋白的相对表达量分别为0.69±0.03,0.16±0.02,均低于Con组GloⅠmRNA和蛋白的相对表达量。结论:雌激素可上调子宫内膜癌KLE细胞中GloⅠmRNA和蛋白的表达。抑制AKT途径可下调子宫内膜癌KLE细胞中GloⅠmRNA和蛋白的表达。AKT途径在雌激素调控子宫内膜癌KLE细胞中GloⅠ的表达无明显作用。 相似文献
47.
Nobuyuki?KutsukakeEmail author Toshikazu?Hasegawa 《International journal of primatology》2005,26(4):775-800
We report a case of turnover between an alpha (GN) and a beta male (R7) and its effects in a troop of provisioned Japanese macaques (Macaca fuscata fuscata) in Shiga-Heights, Nagano Prefecture, Japan. The aggression between the 2 males was caused by the intrusion of GN towards the consort of R7. R7 received support from his brother and mother, and consequently defeated GN. After the turnover, R7 attacked GN frequently, which may have functioned to stabilize the dominance relationship between them. Also, R7 selectively attacked females friendly to GN soon after the turnover. Although we never observed polyadic aggression among males during the stable dominance period, 20 cases of polyadic aggression occurred among the 6 highest-ranked males in the 2 days following the turnover, and one case occurred on the fourth day. R7 and GN formed stable conservative alliances for attacking subordinate males. Males that did not participate in the turnover began to form revolutionary coalitions to attack higher-ranking males, but they were thwarted by the conservative coalitions between the dominants. Mutualism was a plausible explanation for the patterns of coalition formation because most of them were conservative with little associated cost. Seven females had a high proximity index (C-score) to GN before the turnover, but a significantly lower proximity index after the turnover. On the day of the turnover, 6 non-lactating females suddenly became receptive, suggesting that the turnover induced immediate receptivity in the females. 相似文献
48.
Berstein L Kovalevskij A Zimarina T Maximov S Gershfeld E Vasilyev D Baisheva S Baymakhasheva A Thijssen JH 《The Journal of steroid biochemistry and molecular biology》2005,95(1-5):71-74
Aromatase activity (AA) was evaluated totally in 80 tumors collected from primary endometrial cancer (EC) patients. All patients were divided into cases belonging to the types I or II of EC (respectively, 50 and 30 observations). Samples of malignant endometrium from type II demonstrated inclination to the higher AA in comparison with type I samples; the difference reached level of statistical significance in non-smoking patients (p = 0.02). Although no positive correlation was revealed between AA in EC tissue and percentage of cells with DNA damage in normal endometrium from the same patients, the rate of DNA damage (percent of comets, comet's tail average length, etc.) was higher in intact endometrium collected from patients with type II of the disease. In 19 tumor samples, CYP19 gene expression was evaluated by RT-PCR and level of mRNA signal demonstrated positive correlation with AA (Rs = +0.63, p = 0.05) in the whole this material. Of note, though, CYP19 mRNA expression was not revealed in six cases, and all of them belonged to the type I of disease. Finally, in 23 EC patients (15 with type I and 8 with type II of the disease) effects of 2 weeks treatment with letrozole (10 pts) and exemestane (13 pts) were evaluated in neoadjuvant setting. Although diminishing of endometrial M-echo signal and the increases in FSH and LH concentration after treatment were more pronounced in type I patients, decrease in tumor PR content (p = 0.04) was more revealing in patients with type II of EC; besides, the decreases in AA in tumor tissue by the end of treatment were noted predominantly in patients with lower body weight (BMI <27.5). Thus, although type II of EC is frequently considered as hormone-independent, increased ability of this type of the tumor to estrogen biosynthesis (at CYP19 gene and protein level) may lead to the reconsideration of such conclusion and warrants further investigation. The search of possible ethnic differences in AA and in the biologic response to aromatase inhibitors in EC can be of importance too. 相似文献
49.
Temperature is a major climatic factor that limits geographical distribution of plant species, and the reproductive phase has proven to be one of the most temperature-vulnerable stages. Here, we have used peach to evaluate the effect of temperature on some processes of the progamic phase, from pollination to the arrival of pollen tubes in the ovary. Within the range of temperatures studied, 20 degrees C in the laboratory and, on average, 5.7 degrees C in the field, the results show an accelerating effect of increasing temperature on pollen germination and pollen tube growth kinetics, as well as an increase in the number of pollen tubes that reach the style base. For the last two parameters, although the range of temperature registered in the field was much lower, the results obtained in the laboratory paralleled those obtained in the field. Increasing temperatures drastically reduced stigmatic receptivity. Reduction was sequential, with stigmas first losing the capacity to sustain pollen tube penetration to the transmitting tissue, then their capacity to offer support for pollen germination and, finally, their capacity to support pollen grain adhesion. Within a species-specific range of temperature, this apparent opposite effect of temperature on the male and female side could provide plants with the plasticity to withstand changing environmental effects, ensuring a good level of fertilization. 相似文献
50.