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排序方式: 共有119条查询结果,搜索用时 15 毫秒
101.
102.
MBS de Brito MAR Feliciano LN Coutinho RR Uscategui APR Simões MC Maronezi VT de Almeida RM Crivelaro B Gasser L Pavan WR Russiano 《Reproduction in domestic animals》2015,50(5):730-734
The objective was to characterize the vascular patterns of testicular blood flow of adult cats, measuring the systolic velocity (SV), diastolic velocity (DV), resistance index (RI), gate time (wash‐in) peak enhancement and output time (wash‐out) of the contrast and addition of tissue fill characteristics. Forty‐five adult cats were selected, and the echotexture, echogenicity, size, contours and margins of testicles were assessed via ultrasound. By Doppler were evaluated the blood flow and determined of vascular index in testicular artery (SV, DV and RI) and via contrast‐enhanced ultrasonography determine the time for phases: wash‐in, wash‐out and peak enhancement. Sonographic findings presented normal. Testicular artery was observed in the spermatic cord with tortuous patter and showed monophasic‐patterned waves and low vascular resistance and with systolic peak evident. Values of indices vascular were as follows: SV = 6.73 cm/s, DV = 2.8 cm/s and RI = 0.54 for left testicles; and SV = 6.23 cm/s, DV = 2.77 cm/s and RI = 0.53 for right testicles. Contrast filled the subcapsular vascular structures and after a few seconds, a homogeneous moderate enhancement of the parenchyma, with parenchymal vessels still distinguishable and after the peak phase, a rapid homogeneous decrease in echogenicity. Values of time for contrast‐enhanced ultrasonography were as follows: wash‐in = 8.78 s, peak enhancement = 21.62 s and wash‐out = 75.36 for left testicles; and wash‐in = 10.76 s, peak enhancement = 21.50 s and wash‐out = 81.81 for right testicles. Doppler and contrast‐enhanced ultrasonography of the testicles in healthy adult cats was easily implemented and may provide baseline data for this organ to allow the use of these techniques as a diagnostic tool for evaluating testicular abnormalities in sick cats. 相似文献
103.
DH Sandweiss H McInnis RL Burger A Cano B Ojeda R Paredes MC Sandweiss MD Glascock 《Science (New York, N.Y.)》1998,281(5384):1830-1832
Excavations at Quebrada Jaguay 280 (QJ-280) (16 degrees30'S) in south coastal Peru demonstrated that Paleoindian-age people of the Terminal Pleistocene (about 11,100 to 10,000 carbon-14 years before the present or about 13,000 to 11,000 calibrated years before the present) in South America relied on marine resources while resident on the coast, which extends the South American record of maritime exploitation by a millennium. This site supports recent evidence that Paleoindian-age people had diverse subsistence systems. The presence of obsidian at QJ-280 shows that the inhabitants had contact with the adjacent Andean highlands during the Terminal Pleistocene. 相似文献
104.
MC Gye 《Reproduction in domestic animals》2004,39(1):43-47
Tight junctions (TJ) in inter-Sertoli junctional areas and epididymal epithelia are important for the formation of blood-testis barrier (BTB) and blood-epididymal barrier (BEB). In this study, the expression of occludin, an integral member of the TJ, was verified in canine testis and epididymis. Both low molecular weight (MW) (25-28 kDa) forms as well as high MW (68-72 kDa) forms of occludin were detected in the testis and epididymis using Western blot. The relative amount of the high MW forms of occludin vs low MW forms was higher in the testis than in the epididymis. Some difference in the composition of different MW forms of occludin was found along the segments of epididymis, suggesting the possible correlation between cellular composition of occludin proteins and paracellular permeability of epithelia along the epididymal tubule. In the testis, intense occludin immunoreactivity was found in the basally located inter-Sertoli junctional area. Diffused immunoreactivity of occludin was also found in the cytoplasm of Sertoli cells. A similar pattern of zonula occludens-1 immunoreactivity was found in the cytoplasm of Sertoli cells, suggesting that occludin was not confined to the inter-Sertoli junctional areas and that subcellular localization of occludin in the Sertoli cells was dynamically regulated during spermatogenesis in canine testis. In the epididymis weak immunoreactivity was found in the apical sides and cytoplasm of epithelial cells. 相似文献
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107.
F Cairoli D Vigo M Battocchio M Faustini MC Veronesi G Maffeo 《Reproduction in domestic animals》2002,37(5):294-298
The aim of this study was to determine possible links between steroidogenic activity of single ovarian cysts and response to intramuscular treatment with 20 μg of buserelin (GnRH‐analogue) after cyst emptying, in pluriparous Friesian cows bearing a singleton cyst treated not earlier than 55 days post‐partum. Progesterone, 17β‐estradiol and testosterone were determined in cystic fluids collected by needle aspiration of the cyst. Of the cows, 75.6% began ovarian cyclicity within 30 days after treatment with a conception rate of 64.7%. In this study it was found that as progesterone concentration in cystic fluids rose, the number of positive responses to the treatment fell. 相似文献
108.
SUMMARY: Eighty-six horses presented for examination at the Rural Veterinary Centre between January 1986 to December 1991 with acute diarrhoea. The average age of affected horses was 3.2 ± 0.2 years (mean ± SE), with 69% three years or younger. Sixty-one horses were male (36 stallions, 25 geldings) and 83 horses were Thoroughbreds (47) or Standardbreds (36). Sixty-six horses were undergoing routine training at the time of onset of diarrhoea. Eight horses were afflicted with a non-specific illness within one to five days before the onset of diarrhoea, whereas eight horses developed diarrhoea during or within 48 h of discontinuation of antimicrobial therapy. Three horses developed the diarrhoea within 24 h of road transportation. Clinically, the disorder was characterised by a fever, sudden onset of profuse diarrhoea, clinical evidence of dehydration (estimated to be 5 to 12% of body weight at the time of admission) and shock. Degenerative leucopaenia, hyponatraemia, hypochloraemia, hyperkalaemia, hyperglycaemia and azotaemia were characteristic laboratory findings. Laminitis was a sequel in about 30% of cases. The cause of diarrhoea remained undetermined in most cases. Salmonellas were isolated from faecal or tissue samples in only two cases. Similarly, there was no evidence of seroconversion to Erhlichia risticii in 17 cases. Sixty-two of the horses survived the acute phase of the disease in response to supportive care. In horses that did not survive, necropsies were performed and revealed sanguineous or turbid peritoneal fluid. The colonic and caecal walls were oedematous and thickened with serosal congestion and discolouration of these organs evident grossly. Histopathological examination of the caecum and colon revealed diffuse congestion, oedema, inflammatory reactions and submucosal vascular thrombosis with varying degrees of mucosal devitalisation. Most cases presented in this series represent a distinct syndrome of diarrhoea characterised by acute diarrhoea predominantly affecting young horses in training with concomitant signs of fever and toxaemia. 相似文献
109.
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M Villani F Cairoli H Kindahl G Galeati M Faustini A Carluccio MC Veronesi 《Reproduction in domestic animals》2006,41(6):544-548
Very little information is available regarding the physiological mechanisms involved in the normal sexual activity in the stallion and, in particular, the endocrine control of reproduction is still not clearly understood. This experiment was designed to determine the short-term effect of sexual stimulation on plasma concentrations of testosterone, cortisol, oestrone sulphate and 15-ketodihydro-PGF(2alpha) in stallions. Semen samples were collected from 10 lighthorse stallions of proven fertility using a Missouri model artificial vagina. At the same time, blood samples were collected from the jugular vein with heparinized tubes, 20 and 10 min before oestrous mare exposure, at exposure and 10, 20, 30 min after dismounting. Testosterone concentrations showed a sharp rise 10 min after mating (p < 0.001), reached a plateau, and then showed a further increase 30 min after mating (p < 0.001). Cortisol concentrations increased 10 min after mating (p < 0.001) and remained at high levels in the subsequent samples taken. A peak of oestrone sulphate was observed 10 min after mating (p < 0.001). 15-Ketodihydro-PGF(2alpha) concentrations decreased rapidly at the moment of the exposure of the stallions to an oestrous mare (p < 0.05), returned to pre-mating concentrations and then decreased again 30 min after mating (p < 0.05). 相似文献