MEDICAL RESEARCH     

Harvey EN 《Science (New York, N.Y.)》1923,57(1478):501-503

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Distribution of Cytochrome P450-side Chain Cleavage in the Theca Interna Layers of Bovine Small Antral and Cystic Follicles   总被引：1，自引：0，他引：1  

N Isobe  T Nakao  Y Yoshimura 《Reproduction in domestic animals》2003,38(5):405-409

Cystic follicle is anovulatory follicular structure that is caused by an endocrine imbalance. The activity of cytochrome P450‐side chain cleavage (P450scc) is essential for the initiation of steroidogenesis in the follicle. The present study was designed to compare the frequency of cells containing P450scc between healthy and atretic small antral follicles, and among several types (I, II and III, classified based on the presence of granulosa layer) of cystic follicles. Paraffin sections of healthy (2–5 mm in diameter), atretic (2–5 mm) and cystic follicles (>25 mm) were immunohistochemically stained with rabbit polyclonal antibody to bovine P450scc. The P450scc‐positive cells were counted in four different regions of the follicles from the apical to the basal side. In small antral follicles and cystic follicles, P450scc‐positive cells were localized in the theca interna layers but not granulosa layers. The P450scc‐positive cell populations decreased in the late atretic follicles compared with the early and advanced atretic follicles at all the regions of follicle. Type III cystic follicles showed significantly lower frequencies of P450scc‐positive cells than those in the types I and II cystic follicles. These results suggest that in both small and cystic follicles in cows, total loss of granulosa cells may be associated with the reduction of frequency of P450scc‐positive cells in theca interna layer.  相似文献   

Balancing genetic diversity, genetic merit and population viability in conservation programmes     

N. Piyasatian  B. P. Kinghorn 《Zeitschrift für Tierzüchtung und Züchtungsbiologie》2003,120(3):137-149

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Effect of Antiserum and Prolonged Cultivation on the Agglutinative Characteristics of a Type I Meningococcus     

Naiman DN 《Science (New York, N.Y.)》1948,108(2804):334-335

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Inhibition of gastric ulceration in the rat by o-hydroxybenzoic (salicylic) acid     

PAULS F  WICK AN  MACKAY EM 《Science (New York, N.Y.)》1948,107(2766):19-20

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Na/K-ATPase activity during larval development in the giant freshwater prawn Macrobrachium rosenbergii and the effects of salinity on survival rates     

Do Thi  Thanh HUONG  Vidya  JAYASANKAR  Safiah  JASMANI  Hisako  SAIDO-SAKANAKA  Andrew J.  WIGGINTON  Marcy N.  WILDER 《Fisheries Science》2004,70(3):518-520

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Characterization of ovine PrP gene promoter activity in N2a neuroblastoma and ovine foetal brain cell lines   总被引：1，自引：0，他引：1  

G. T. O'Neill  K. Donnelly  E. Marshall  D. Cairns  W. Goldmann  N. Hunter 《Zeitschrift für Tierzüchtung und Züchtungsbiologie》2003,120(2):114-123

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Science at Cornell     

N H 《Science (New York, N.Y.)》1886,7(167):352

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Muscarinic receptor subtypes in equine tracheal smooth muscle     

M. Yu  N. E. Robinson  Z. Wang  F. J. Derksen 《Veterinary research communications》1992,16(4):301-310

Selective muscarinic receptor antagonists were used to identify muscarinic receptor subtypes in equine trachealis strips. The M₁ receptor antagonist pirenzepine (10^–7 mol/L to 3 × 10^–5 mol/L) and the M₃ receptor antagonist 4-diphenylacetoxy-N-methylpiperidine (4-DAMP, 10^–9 mol/L to 3 × 10^–7 mol/L³) dose dependently inhibited the contractile responses to electrical field stimulation (EFS) and exogenous acetylcholine (ACh). Schild plots yielded a pA₂ value for pirenzepine vs ACh of 6.75 ± 0.09, which is consistent with the affinity for M₂ or M₃ receptors, and a pA₂ value for 4-DAMP vs ACh of 8.47 ± 0.09, which is in agreement with the affinity for M₃ receptors. The M₂ receptor antagonist gallamine (10^–5 mol/L and 10^–4 mol/L) did not affect the response of trachealis to exogenous ACh and low-frequency EFS (0.1–2 Hz) but decreased the responses to high-frequency EFS (4–16 Hz). These results suggest that the muscarinic receptors mediating contractions induced by ACh in equine tracheal smooth muscle are of the M₃ subtype. The lack of an increase in the response to EFS following gallamine suggests that functional prejunctional inhibitory M₂ receptors are not present on the cholinergic nerves innervating equine tracheal smooth muscle.  相似文献   

FREEZING BOAR SEMEN IN FLAT PLASTIC BAGS MEMBRANE INTEGRITY and FERTILITY     

H. Rodriguez-Martinez  B. Eriksson  N. Lundeheim 《Reproduction in domestic animals》1995,31(1):161-168

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