全文获取类型
收费全文 | 224篇 |
免费 | 21篇 |
出版年
2023年 | 1篇 |
2019年 | 4篇 |
2018年 | 11篇 |
2017年 | 8篇 |
2016年 | 5篇 |
2015年 | 3篇 |
2014年 | 3篇 |
2013年 | 5篇 |
2012年 | 12篇 |
2011年 | 10篇 |
2010年 | 1篇 |
2009年 | 5篇 |
2008年 | 10篇 |
2007年 | 5篇 |
2006年 | 4篇 |
2005年 | 2篇 |
2004年 | 7篇 |
2003年 | 8篇 |
2002年 | 2篇 |
2001年 | 9篇 |
2000年 | 12篇 |
1999年 | 6篇 |
1998年 | 1篇 |
1996年 | 1篇 |
1995年 | 1篇 |
1994年 | 1篇 |
1993年 | 1篇 |
1992年 | 4篇 |
1991年 | 10篇 |
1990年 | 7篇 |
1989年 | 13篇 |
1988年 | 6篇 |
1987年 | 7篇 |
1986年 | 10篇 |
1985年 | 8篇 |
1984年 | 7篇 |
1983年 | 3篇 |
1982年 | 4篇 |
1981年 | 1篇 |
1980年 | 3篇 |
1979年 | 6篇 |
1978年 | 4篇 |
1977年 | 4篇 |
1976年 | 4篇 |
1974年 | 1篇 |
1973年 | 1篇 |
1972年 | 2篇 |
1971年 | 1篇 |
1969年 | 1篇 |
排序方式: 共有245条查询结果,搜索用时 74 毫秒
51.
Ott TL Van Heeke G Hostetler CE Schalue TK Olmsted JJ Johnson HM Bazer FW 《Theriogenology》1993,40(4):757-769
The ability of recombinant ovine interferon-tau (roIFNtau) to extend the interestrous interval (IEI) in sheep was studied. Ewes were fitted with bilateral uterine catheters 7 or 8 days post estrus and were assigned to receive either 10 or 20 million antiviral (AV) units/day i.u. ( approximately 100 or 200 ug) of roIFNtau or ovine conceptus secretory proteins containing equivalent AV units of native oIFNtau (noIFNtau; 4 ewes/treatment). Four control ewes received ovine serum proteins (SP). Total protein injected was 6 mg per day, half at 0700 hours and half at 1730 hours. The treatments were administered from Day 11.5 (estrus=Day 0) to Day 16. Blood samples were collected by jugular vienipuncture daily from Day 11 until ewes returned to estrus. Concentrations of progesterone (P) in plasma were determined by RIA. Treatment with either noIFNtau or roIFNtau extended IEI beyond that of SP-treated ewes (19.1 vs 31.2+/-3.4 days P<0.03). Of the ewes receiving 100 mug/day of oIFNtau, 2 of 4 receiving noIFNtau (23.6+/-5.2 days) and 3 of 4 receiving roIFNtau (34.2+/-5.2 days) had an extended IEI. All ewes receiving 200 mug/day of noIFNtau or roIFNtau had an extended IEI (28.8 and 38.5+/-5.2 days. respectively). Ewes receiving roIFNtau had a longer IEI than those receiving noIFNtau (36.7 vs 26.2+/-3.4 days; P=0.07). Ewes with an extended IEI had functional corpora lutea, as assessed by P production. The results demonstrate that 10 or 20 million AV units ( approximately 100 or 200 ug) of roIFNtau extends the IEI and that the length of the IEI is longer for ewes receiving roIFNtau than noIFNtau following injection of equivalent AV units. 相似文献
52.
53.
Conceptus (placental membranes, fetal fluids and fetus) development was characterized between Days 27 and 111 of gestation. Progestagens, oestrone, oestradiol, oestrone sulphate and prostaglandins (PG) F were measured in maternal plasma and allantoic and amniotic fluids. Protein concentrations are described for fetal fluids. The early increase in placental membrane weight from 1.12 g (27 days) to 58.45 g (50 days) was associated with oestrogen production presumably of conceptus origin. Oestrogens increased significantly in allantoic and amniotic fluids throughout the period studied with oestrone being the primary free oestrogen, rising from 2 pg/ml (Day 33) to 144 ng/ml by 111 days in allantoic fluid. Changes in plasma oestrogens of the maternal circulation were not detected until after Day 70 at which time oestrone concentration was greater than that of oestradiol. Fetal fluid concentrations of progestagens, oestrone sulphate and PGF were not related to maternal plasma levels and a sequestration of these hormones by the allantois is postulated. 相似文献
54.
J T Zavy R Mayer M W Vernon F W Bazer D C Sharp 《Journal of reproduction and fertility. Supplement》1979,(27):403-411
Uterine flushings were collected from 30 non-pregnant Pony mares on Days 8, 12, 14, 16, 18 or 20 after oculation. Mares were allowed a recovery period of one oestrous cycle and were mated at the next oestrus. They were then ovario-hysterectomized on days which corresponded to the day of the oestrous cycle to which they were assigned. Uterine flushings were analysed for total recoverable protein and acid phosphatase activity. Least squares analysis indicated a status X day interaction for total protein (P less than 0.10) and acid phosphatase activity (P less than 0.005) in which the latter was higher in uterine flushings during pregnancy. Peripheral plasma oestrone and oestradiol concentrations were measured by radioimmunoassay and results indicated that plasma oestrone concentrations in pregnant and non-pregnant mares were not different, and oestradiol was lower (P less then 0.005) in the peripheral plasma during pregnancy. conceptus membranes were incubated in vitro for 120 min in a chemically defined medium. Incubation medium was then assayed to assess oestrone and oestradiol production capacilities at Days 8, 12, 14, 16, 18 and 20 of pregnancy. Conceptus membrane production of oestradios (pg/5 ml/h) increased (P less than 0.05) from Day 8 (243 pg/5 ml) to Day 20 (108 763 pg/5 ml). A similar trend, but of lower magnitude, existed for oestrone production. 相似文献
55.
One of the problems associated with in vitro culture of primordial germ cells (PGCs) is the large loss of cells during the initial period of culture. This study characterized the initial loss and determined the effectiveness of two classes of apoptosis inhibitors, protease inhibitors, and antioxidants on the ability of porcine PGCs to survive in culture. Results from electron microscopic analysis and in situ DNA fragmentation assay indicated that porcine PGCs rapidly undergo apoptosis when placed in culture. Additionally, alpha(2)-macroglobulin, a protease inhibitor and cytokine carrier, and N:-acetylcysteine, an antioxidant, increased the survival of PGCs in vitro. While other protease inhibitors tested did not affect survival of PGCs, all antioxidants tested improved survival of PGCs (P: < 0.05). Further results indicated that the beneficial effect of the antioxidants was critical only during the initial period of culture. Finally, it was determined that in short-term culture, in the absence of feeder layers, antioxidants could partially replace the effect(s) of growth factors and reduce apoptosis. Collectively, these results indicate that the addition of alpha(2)-macroglobulin and antioxidants can increase the number of PGCs in vitro by suppressing apoptosis. 相似文献
56.
57.
58.
Thomas?E?SpencerEmail author Fuller?W?Bazer 《Reproductive biology and endocrinology : RB&E》2004,2(1):45
In mammals, a carefully orchestrated dialogue between the mother and conceptus (embryo/fetus and associate extraembryonic membranes) is initiated during the peri-implantation period of pregnancy as the trophoblast develops, functions to signal pregnancy recognition, and initiates implantation. The purpose of this Forum is to highlight comparative aspects of trophoblast morphogenesis and function in mammals. 相似文献
59.
M.P. Eddy Moeljono W.W. Thatcher Fuller W. Bazer Marilyn Frank Linda J. Owens andC.J. Wilcox 《Prostaglandins & other lipid mediators》1977,14(3)
Polyvinyl catheters were inserted into the right and left utero-ovarian veins (UOV) and saphenous vein (SV) and artery (SA)_of six nonpregnant (O) and five pregnant (P) gilts on day 11 after onset of estrus. Beginning on day 12, UOV blood samples were collected at 15-min intervals from 0800 to 1100 hr and 2000 to 2300 hr, and single samples were taken at 1200 and 2400 hrs. Peripheral blood (SA or SV) was sampled at 0800, 1200, 2000 and 2400 hr until gilts returned to estrus (
) or day 24 or pregnancy. UOV plasma PGF concentrations (ng/ml; n = 1929) were measured by RIA. Status (P
O) by day interactions were detected (P<.01) but variances among treatments were heterogenous (P<.01). Cuvilinear day trends were detected for PGF in 0 gilts (P<.01) but not P gilts. PGF peaks, defined as concentrations greater than two SD above the mean concentration for each gilt, occurred with greater frequency ((ifχ2 = 16.4; P>.01)) in 0 than P gilts; and mean peak levels (
) were 5.0 ± .27 and 3.84 ± .13 ng/ml, respectively.Progesterone concentrations were maintaiend in pregnant pigs and were indicative of luteal maintenance. Systematic differences in day trends of utero-ovarian venous plasma estradiol were detected between O and P pigs. These differences may be of paramount physiological importance and are discussed. 相似文献
60.
Porcine conceptus secretory proteins (pCSP) were obtained from medium in which pig conceptuses, collected on Day 15 of pregnancy, were cultured for 30 h. Culture medium was pooled, dialyzed, and concentrated by Amicon ultrafiltration for intrauterine infusion. Serum proteins (SP) were obtained from blood collected from a Day 15 pregnant gilt and diluted for intrauterine infusion. Catheters were placed into both uterine horns and the inferior vena cava of cyclic (Day 8) gilts. Single blood samples were collected at 0800 h on Days 9, 10, and 11. On Day 11, all gilts received 1 mg estradiol-17 beta (E2) i.m. at 0800 h. Protein infusions commenced on Day 12 and continued through Day 15, twice daily at 0800 h and 2000 h. Protein infusions per uterine horn were (1) 4.0 mg pCSP + 4.0 mg SP (pCSP, 4 gilts) and (2) 8.0 mg SP (SP, 4 gilts). Blood samples were collected every 15 min on Days 12 through 17 between 0805 h and 1100 h. Single blood samples were collected at 0800 h after Day 17 until gilts exhibited estrus. Concentrations of prostaglandin (PG) E, 13,14-dihydro-15-keto-PGF2 alpha (PGFM), and progesterone (P4) were measured by specific radioimmunoassays. Interestrous intervals for pCSP-treated (18.2 days) and SP-treated (18.0 days) gilts were not different (SEM = 0.8 days) and temporal changes in concentrations of P4 in plasma did not differ between pCSP-treated (29.2 ng/ml) and SP-treated (31.2 ng/ml) gilts.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献