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排序方式: 共有1693条查询结果,搜索用时 156 毫秒
61.
Haney SAMIR Kazuaki SASAKI Eman AHMED Aly KAREN Kentaro NAGAOKA Mohamed EL SAYED Kazuyoshi TAYA Gen WATANABE 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2015,77(5):549-556
Although color Doppler ultrasonography has been used to evaluate testicular blood flow in
many species, very little has been done in goat. Eight male Shiba goats were exposed to a
single intramuscular injection of either gonadotropin-releasing hormone (GnRH group; 1
µg/kg BW) or human chorionic gonadotropin (hCG group; 25 IU/kg BW).
Plasma testosterone (T), estradiol (E2) and inhibin (INH) were measured just before (0 hr)
and at different intervals post injection by radioimmunoassay. Testis volume (TV) and
Doppler indices, such as resistive index (RI) and pulsatility index (PI) of the
supratesticular artery, were measured by B-mode and color Doppler ultrasonography,
respectively. The results indicated an increase in testicular blood flow in both groups,
as RI and PI decreased significantly (P<0.05), but this increase was
significant higher and earlier in hCG group (1 hr) than in the GnRH group (2 hr). A high
correlation was found for RI and PI with both T (RI, r= −0.862; PI, r= −0.707) and INH in
the GnRH group (RI, r=0.661; PI, r=0.701). However, a significant
(P<0.05) correlation was found between E2 and both RI (r= −0.610) and
PI (r= −0.763) in hCG group. In addition, TV significantly increased and was highly
correlated with RI in both groups (GnRH, r= −0.718; hCG, r= −0.779). In conclusion, hCG
and GnRH may improve testicular blood flow and TV in Shiba goats. 相似文献
62.
Yojiro YANAGAWA Yukiko MATSUURA Masatsugu SUZUKI Shin-ichi SAGA Hideto OKUYAMA Daisuke FUKUI Gen BANDO Masashi NAGANO Seiji KATAGIRI Yoshiyuki TAKAHASHI Toshio TSUBOTA 《The Journal of reproduction and development》2015,61(1):61-66
Generally, sika deer conceive a single fetus, but approximately 80% of pregnant females have two corpora lutea (CLs). The function of the accessory CL (ACL) is unknown; moreover, the process of ACL formation is unclear, and understanding this is necessary to know its role. To elucidate the process of ACL formation, the ovarian dynamics of six adult Hokkaido sika deer females were examined ultrasonographically together with peripheral estradiol-17β and progesterone concentrations. ACLs formed in three females that conceived at the first estrus of the breeding season, but not in those females that conceived at the second estrus. After copulation, postconception ovulation of the dominant follicle of the first wave is induced by an increase in estradiol-17β, which leads to formation of an ACL. A relatively low concentration of progesterone after the first estrus of the breeding season is considered to be responsible for the increase in estradiol-17β after copulation. 相似文献
63.
Hamster sperm hyperactivation is enhanced by progesterone, and this progesterone-enhanced hyperactivation is suppressed by 17β-estradiol (17βE2) and γ-aminobutyric acid (GABA). Although it has been indicated that melatonin also enhances hyperactivation, it is unknown whether melatonin-enhanced hyperactivation is also suppressed by 17βE2 and GABA. In the present study, melatonin-enhanced hyperactivation was significantly suppressed by 17βE2 but not by GABA. Moreover, suppression of melatonin-enhanced hyperactivation by 17βE2 occurred through non-genomic regulation via the estrogen receptor (ER). These results suggest that enhancement of hyperactivation is regulated by melatonin and 17βE2 through non-genomic regulation. 相似文献
64.
65.
Tetsuji Ota Tsuyoshi Kajisa Nobuya Mizoue Shigejiro Yoshida Gen Takao Yasumasa Hirata Naoyuki Furuya Takio Sano Raul Ponce-Hernandez Oumer S. Ahmed Heng Sokh Vuthy Ma Eriko Ito Jumpei Toriyama Yukako Monda Hideki Saito Yoshiyuki Kiyono Sophal Chann Nang Ket 《Journal of Forest Research》2015,20(6):484-492
66.
67.
Taguchi H Watanabe S Hirao T Akiyama H Sakai S Watanabe T Matsuda R Urisu A Maitani T 《Journal of agricultural and food chemistry》2007,55(5):1649-1655
Kiwifruit (Actinidia deliciosa and Actinidia chinensis) is allergenic to sensitive patients, and, under Japanese regulations, it is one of the food items that are recommended to be declared on food labeling as much as possible. To develop PCR-based methods for the detection of trace amounts of kiwifruit in foods, two primer pairs targeting the ITS-1 region of the Actinidia spp. were designed using PCR simulation software. On the basis of the known distribution of a major kiwifruit allergen (actinidin) within the Actinidia spp., as well as of reports on clinical and immunological cross-reactivities, one of the primer pairs was designed to detect all Actinidia spp. and the other to detect commercially grown Actinidia spp. (i.e., kiwifruit, Actinidia arguta, and their interspecific hybrids) except for Actinidia polygama. The specificity of the developed methods using the designed primer pairs was verified by performing PCR experiments on 8 Actinidia spp. and 26 other plants including fruits. The methods were considered to be specific enough to yield target-size products only from the target Actinidia spp. and to detect no target-size products from nontarget species. The methods were sensitive enough to detect 5-50 fg of Actinidia spp. DNA spiked in 50 ng of salmon testis DNA used as a carrier (1-10 ppm of kiwifruit DNA) and 1700 ppm (w/w) of fresh kiwifruit puree spiked in a commercial plain yogurt (corresponding to ca. 10 ppm of kiwifruit protein). These methods would be expected to be useful in the detection of hidden kiwifruit and its related species in processed foods. 相似文献
68.
Nishimura M Ishiyama K Watanabe A Kawano S Miyase T Sano M 《Journal of agricultural and food chemistry》2007,55(18):7252-7257
A quantitative method for four theaflavins and two methylated theaflavin derivatives in black tea leaves was developed by solid-phase extraction and a high-performance liquid chromatographic method with photodiode array detection. The theaflavins in black tea leaves were extracted three times with 40 vol 50% aqueous ethanol (mg dry tea powder/mL) containing 2% ascorbic acid. The ethanol extracts were diluted 4-fold with distilled water. All diluted extracts were directly applied to the solid-phase C18 cartridge column without concentration. The fraction of theaflavins was obtained by 40% ethanol extraction after rinsing with water followed with 15% ethanol extraction. An aliquot of theaflavins after concentration was injected onto an ODS C18 reversed-phase column, and four theaflavins and two methylated theaflavins were sufficiently separated by a linear gradient system using distilled water and acetonitrile with 0.5% acetic acid. This analytical method is sensitive for the determination of a small amount of methylated theaflavins, since various interfering substances produced during the fermentation process were eliminated in advance by solid-phase extraction. Using this analytical method, we also demonstrated that methylated theaflavins were easily produced during the manufacture of black tea. 相似文献
69.
70.