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Congenital portosystemic shunts in Maltese and Australian Cattle Dogs   总被引:2,自引:0,他引:2  
SUMMARY Congenital portosystemic shunts were definitively diagnosed in 62 dogs over a period of 15 years. Maltese and Australian Cattle Dogs were significantly over-represented, accounting for 14 and 13 cases, respectively. Maltese invariably had a single extrahepatic shunt derived from the left gastric or gastrosplenic vein, whereas Cattle Dogs usually had large intrahepatic shunts involving the right liver lobes. The clinical syndromes resulting from anomalous portosystemic communications were indistinguishable in the 2 breeds. Fasting blood ammonia concentration was elevated in 20 of 22 dogs tested, providing a minimally invasive and effective means of diagnosis. Complete or partial shunt attenuation was performed successfully in all 9 Maltese and in 2 of 6 Cattle Dogs in which it was attempted.  相似文献   
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A fusion defect of the proximal and middle phalanges of both hindlimbs, osteochondrosis dissecans of the distal interphalangeal joints of the forelimbs, and subluxation of all 4 distal interphalangeal joints occurred in a Standardbred filly. Lameness was the first abnormality noted and was observed at one week of age in the left forelimb and progressed until all 4 limbs were affected by 5 weeks of age. On radiographs of both forelimbs, the distal interphalangeal joints were subluxated with irregularity and lucency of subchondral bone. On radiographs of the distal hindlimbs, there was a subluxation of both distal interphalangeal joints and loss of the proximal interphalangeal joint spaces with fusion of the proximal and middle phalanges. The foal was euthanised. On necropsy, there were focal areas of erosion of articular cartilage in the distal interphalangeal joint of both forelimbs. The proximal and middle phalanges of both hindlimbs were fused. Histopathological examination of the distal interphalangeal joint of the right foreleg showed loss of articular cartilage and degenerative changes in the exposed subchondral bone.  相似文献   
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Objective To perform in vivo analysis of retinal functional and structural parameters in healthy mouse eyes. Animal Studied Adult C57BL/6 male mice (n?=?37). Procedures Retinal function was evaluated using pattern electroretinography (pERG) and the chromatic pupil light reflex (cPLR). Structural properties of the retina and nerve fiber layer (NFL) were evaluated using spectral-domain optical coherence tomography (SD-OCT). Results The average pERG amplitudes were found to be 11.2?±?0.7?μV (P50-N95, mean?±?SEM), with an implicit time for P50-N95 interval of 90.4?±?5.4?ms. Total retinal thickness was 229.5?±?1.7?μm (mean?±?SEM) in the area centralis region. The thickness of the retinal nerve fiber layer (mean?±?SEM) using a circular peripapillary retinal scan centered on the optic nerve was 46.7?±?0.9?μm (temporal), 46.1?±?0.9?μm (superior), 45.8?±?0.9?μm (nasal), and 48.4?±?1?μm (inferior). The baseline pupil diameter was 2.1?±?0.05?mm in darkness, and 1.1?±?0.05 and 0.56?±?0.03?mm after stimulation with red (630?nm, luminance 200?kcd/m(2) ) or blue (480?nm, luminance 200?kcd/m(2) ) light illumination, respectively. Conclusions Pattern electroretinography, cPLR and SD-OCT analysis are reproducible techniques, which can provide important information about retinal and optic nerve function and structure in mice.  相似文献   
75.
To test the hypothesis that orexin-B acts directly on the anterior pituitary to regulate LH and growth hormone (GH) secretion, anterior pituitary cells from prepuberal gilts were studied in primary culture. On day 4 of culture, 10(5) cells/well were challenged with 0.1, 10 or 1000 nM GnRH; 10, 100 or 1000 nM [Ala15]-hGRF-(1-29)NH2 or 0.1, 1, 10 or 100 nM, orexin-B individually or in combinations with 0.1 and 1000 nM GnRH or 10 and 1000 nM GRF. Secreted LH and GH were measured at 4 h after treatment. Basal LH and GH secretion (control; n = 6 pigs) was 183 +/- 18 and 108 +/- 4.8 ng/well, respectively. Relative to control at 4 h, all doses of GnRH and GRF increased (P < 0.0001) LH and GH secretion, respectively. All doses of orexin-B increased (P < 0.01) LH secretion, except for the 0.1 nM dose. Basal GH secretion was unaffected by orexin-B. Addition of 1, 10 or 100 nM orexin-B in combinations with 0.1 nM GnRH increased (P < 0.001) LH secretion compared to GnRH alone. Only 0.1 nM (P = 0.06) and 100 nM (P < 0.001) orexin-B in combinations with 1000 nM GnRH increased LH secretion compared to GnRH alone. All doses of orexin-B in combination with 1000 nM GRF suppressed (P < 0.0001) GH secretion compare to GRF alone, while only 0.1 nM orexin-B in combination with 10 nM GRF suppressed (P < 0.01) GH secretion compared to GRF. These results indicate that orexin may directly modulate LH and GH secretion at the level of the pituitary gland.  相似文献   
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77.
对仔猪腹泻病进行了摸索、研究和总结,根据不同日龄和不同临床表现进行鉴别诊断,同时可采取组织病理学、微生物学方法进一步确诊,并采取针对性防治措施,才能有效地控制仔猪腹泻病.  相似文献   
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This study was conducted to determine whether chronic hCG treatment would cause regression of induced corpora lutea (CL) in mature cyclic gilts. Thirty-two mature gilts that had displayed one or more estrous cycles of 18 to 22 d were used. Sixteen gilts were hysterectomized (HYSTX) on d 6 to 9 (d 0 = onset of estrus) and their CL were marked with charcoal (spontaneous group). Sixteen gilts (induced group) were injected with 1,500 IU of pregnant mare's serum gonadotropin (PMSG) on d 6 and 500 IU of hCG on d 9 (day of hCG = d 0 of the induced cycle). Ovulation was assumed to occur on d 2 of the induced cycle. Induced gilts were HYSTX on d 8 to 9 (d 17 to 18 of the original spontaneous cycle) and their CL were marked with charcoal. Only gilts (n = 14) in which induced CL were present and in which the original CL had regressed were then subjected to treatment with saline or hCG. From d 10 to 29, gilts with spontaneous CL were injected daily with 500 IU of hCG (n = 8) or saline (n = 8). From d 10 to 29 of the induced cycle, induced gilts were injected daily with 500 IU of hCG (n = 6) or saline (n = 8). Jugular blood samples were collected every other day from all gilts beginning on the 1st d of daily hCG treatment and quantified for estradiol and progesterone by RIA. On the day after the last hCG injection, the number of charcoal-marked CL and charcoal-marked corpora albicantia (CA) were determined.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
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