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41.
Ikuo Momohara Yuko Ota Takehiro Yamaguchi Makoto Ishihara Yoshihiro Takahata Hajime Kosaka 《Journal of Wood Science》2013,59(5):442-447
The decay risk of airborne wood-decay fungi in the same volume of air was investigated by using an air sampler over the course of a year at three different sampling sites. Japanese cedar disks measuring 7.8 cm in diameter and about 3 mm in thickness, and with a moisture content of about 100 % were placed in a “BIOSAMP” air sampler and then exposed to 1000 l of air in the northern, central, and southwest parts of Japan. The exposed disks were incubated for 20 weeks in a damp container maintained at 26 ± 2 °C and degraded by fungi trapped on the disks. The decay risk was calculated from the mass loss during incubation, and the factors affecting the said risk were explored. The results showed that sampling sites apparently do not affect decay risk, even though the Scheffer’s climate indexes of the sites were quite different. The relation between the sampling month and decay risk reveals that decay risk remains virtually the same year-round. Relative humidity on a sampling day is one of the key factors affecting decay risk in sampling conducted at the central or southwest site. In contrast, no weather factors influenced decay risk at the northern sampling site. 相似文献
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The present study was conducted to investigate whether a portable CO2 incubator was effective for in vitro maturation (IVM) of bovine, porcine and minke whale oocytes, and the effect of maturation media supplemented with different hormones; porcine follicle stimulating hormone (pFSH), estradiol-17beta (E2), or pregnant mare's serum gonadotropin (PMSG): human chorionic gonadotropin (hCG) for minke whale immature oocytes was also examined. In vitro maturation rates of bovine and porcine oocytes cultured in the portable CO2 incubator were not significantly different from the standard CO2 incubator. In minke whale IVM culture using the portable incubator, the maximum expansion of cumulus mass was observed by pFSH/E2 and PMSG/hCG at the end of IVM culture. Moreover, the IVM culture period was shortened to 28-30 h from 96-120 h previously reported. The proportion of matured oocytes cultured in the medium supplemented with pFSH/E2 (26.7%) was significantly higher (P<0.05) than that with PMSG/hCG (6.9%). The present study indicates that a portable CO2 incubator is a useful device for minke whale IVM culture on a research base ship, and the addition of pFSH/E2 into an IVM medium enhanced cumulus expansion and the proportion of minke whale matured oocytes. 相似文献
45.
Ishida R Masuda K Kurata K Ohno K Tsujimoto H 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》2004,18(1):25-30
Lymphocyte blastogenic responses against food allergens in dogs with food hypersensitivity were evaluated in this study. Eleven dogs with food hypersensitivity, based on food elimination and oral food provocation tests and allergic responses to food allergens, were examined by various tests such as intradermal testing, antigen-specific IgE testing, and lymphocyte blastogenic responses. The number and kinds of food allergens identified as positive by these tests were compared with the offending food allergens that were found in an oral food provocation test. In 9 (82%) of the 11 dogs with food hypersensitivity, there was close agreement for positive allergens between the results of lymphocyte blastogenic responses and oral food provocation test; however, there was little agreement for intradermal and IgE testing of the positive allergens with those of the oral food provocation test (11% and 31%, respectively). In the 9 dogs, the stimulation indices of lymphocyte blastogenic responses increased to 2.0-10.1 upon food provocation but decreased significantly to 0.7-1.4 upon feeding the elimination diet until clinical signs disappeared. These results indicate that lymphocyte blastogenic responses may fluctuate because of exposure to offending food allergens in dogs with food hypersensitivity. Lymphocytes reactive to food allergens may play an important role in the pathogenesis of food hypersensitivity in dogs. 相似文献
46.
Nagahata H 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2004,66(12):1475-1482
Bovine leukocyte adhesion deficiency (BLAD) in Holstein cattle is an autosomal recessive congenital disease characterized by recurrent bacterial infections, delayed wound healing and stunted growth, and is also associated with persistent marked neutrophilia. The molecular basis of BLAD is a single point mutation (adenine to guanine) at position 383 of the CD18 gene, which caused an aspartic acid to glycine substitution at amino acid 128 (D128G) in the adhesion molecule CD18. Neutrophils from BLAD cattle have impaired expression of the beta2 integrin (CD11a,b,c/CD18) of the leukocyte adhesion molecule. Abnormalities in a wide spectrum of adherence dependent functions of leukocytes have been fully characterized. Cattle affected with BLAD have severe ulcers on oral mucous membranes, severe periodontitis, loss of teeth, chronic pneumonia and recurrent or chronic diarrhea. Affected cattle die at an early age due to the infectious complications. Holstein bulls, including carrier sires that had a mutant BLAD gene in heterozygote were controlled from dairy cattle for a decade. The control of BLAD in Holstein cattle by publishing the genotypes and avoiding the mating between BLAD carriers was found to be successful. This paper provides an overview of the genetic disease BLAD with reference to the disease in Holstein cattle. 相似文献
47.
Watanabe H Mogoe T Asada M Hayashi K Fujise Y Ishikawa H Ohsumi S Miyamoto A Fukui Y 《The Journal of reproduction and development》2004,50(4):419-427
The present study was conducted to obtain new information on relationships among serum testosterone (T), estradiol-17 beta (E(2)), follicle-stimulating hormone (FSH), and luteinizing hormone (LH) concentrations and histology of seminiferous tubules in captured common minke and Bryde's whales during the feeding season. Blood samples and testes were collected from common minke (n=39 for blood samples, n=15 for testes) and Bryde's (n=14 for blood samples, n=7 for testes) whales captured from May 2001 to August 2001 in the Western North Pacific. Serum T concentrations, in 35.9% of the common minke and 57.1% of Bryde's whales, were below the detection limit (< 2.5 pg/ml). There were no significant differences in the serum concentrations of E(2), FSH, and LH among immature, mature common minke and Bryde's whales except that LH levels of immature Bryde's whales was higher than those of common minke whales. In most seminiferous tubules of mature whales, only a single-layer of spermatogonia was observed. However, spermatozoa were observed in seminiferous tubules in 2/13 of mature common minke and 4/4 of mature Bryde's whales with the low or undetectable T levels. These results indicate that the low serum T concentrations reflect the inactivity of spermatogenesis in both baleen whales, and that it is not possible to assess gonadal activity in either common minke or Bryde's whales using serum sex hormone concentrations during the feeding season. 相似文献
48.
Tetsuka M Asada M Mogoe T Fukui Y Ishikawa H Ohsumi S 《The Journal of reproduction and development》2004,50(4):381-389
This study describes the morphological and morphometrical changes associated with prepubertal ovarian development in the Antarctic minke whale (Balaenoptera bonaerensis). Ovaries were harvested from 94 immature minke whales caught in the Antarctic Ocean during the summer feeding season (December-March). Notable differences in ovarian size and morphology were found among animals. Up to 10 folds difference in ovarian weight was found among prepubertal whales of similar body size. During the prepubertal period, ovaries grew slowly and approximately doubled their weight. The morphologies of right and left ovaries were almost identical while the growth of the ovary appears to occur preferentially on the right side. The most striking morphological feature was numerous small antral follicles less than 5 mm in diameter found in ovaries of younger immature whales. The occurrence of these ovaries was highest in whales less than 6 m long and gradually decreased as body length increased. In larger whales, the occurrence of ovaries with a smaller number of follicles up to 10 mm and thick tunica albuginea increased. Thus, the ovary of the Antarctic minke whale experiences bursts of small follicular development during the early prepubertal period before becoming a more developed ovary with fewer but larger follicles, and thick tunica albuginea. 相似文献
49.
Shibata SJ Hiramatsu Y Kaseda M Chosa M Ichihara N Amasaki H Hayakawa T Asari M 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2006,68(11):1143-1147
Lymph drainage routes from the abdominal and pelvic cavities in beagle dogs were observed serially by following the time course of India ink administered intraperitoneally. Four systems of lymph drainage routes from the peritoneal cavity were observed in this study. The earliest drainage returned to the cranial mediastinal lymph nodes via the sternal lymph vessels; subsequently, the sternal lymph nodes located along the internal thoracic artery became involved. Then, a drainage route via the lymph vessel along the left vagus nerve was observed. The final drainage route flowed into the lateral lymph vessel through the thoracic duct located on the vertebra. These results show that India ink is absorbed from the peritoneal cavity, and that the lymph drainage first flows mainly towards the cranial mediastinal lymph nodes through the ventral lymphatic channels. Our serial observations suggest that, over time, the lymph drainage routes changed from the ventral abdominal to the dorsal thoracic lymphatic channels in the thorax. 相似文献
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