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101.
Gianluca Neglia Bianca Gasparrini Domenico Vecchio Marcello Rubessa Rossella Di Palo Luigi Zicarelli Giuseppe Campanile 《Tropical animal health and production》2010,42(6):1243-1247
The aim of this study was to evaluate the effect of exogenous progesterone supplementation on superovulatory response in buffaloes
that has undergone a multiple ovulation program. Fourteen Mediterranean buffaloes were divided into two groups and received
a 4-day decreasing dosage of an equal mixture of 500 IU of FSH and LH starting on day 8 of the cycle. In group A (n = 7) a progesterone-releasing intravaginal device was removed on day 8, whereas in group B (n = 7) it was left till day 10, when PGF2a {\hbox{PG}}{{\hbox{F}}_{{2}\alpha }} was administered. Eighty hours later, buffaloes were artificially inseminated and after 6 days they undergone uterine flushing.
A higher (P < 0.05) number of corpora lutea (8.3 vs. 5.7) and embryo/flushing/buffalo (2.3 vs. 1.3) were recorded in group B vs. group
A if responsive buffaloes are considered (n = 12) and the number of corpora lutea was highly correlated with the number of embryos (r = 0.65; P < 0.05). In conclusion, progesterone supplementation during the first 2 days of the superovulation treatment seems to enhance
the recovery rate in buffalo species. A high ovulation rate, associated with a high number of corpora lutea, can represent
a parameter for estimating embryo recovery. 相似文献
102.
Alemayehu Regassa Asmelash Tassew Kebede Amenu Bekele Megersa Fufa Abunna Berhanu Mekibib Tanguy Macrotty Gobena Ameni 《Tropical animal health and production》2010,42(5):915-920
A cross-sectional study was conducted in Hawassa town and its surroundings from October 2007 to May 2008 to estimate the prevalence
of bovine tuberculosis (BTB) based on comparative interadermal tuberculin test (CIDT) and abattoir survey. Accordingly, 39
herds comprising 413 cattle were subjected to CIDT, and the herd and individual animal prevalence were 48.7% (19/39) and 11.6%
(48/413), respectively. One of the 16 milk samples collected from tuberculin-positive cows was culture positive. The prevalence
significantly differed among the age group (P = 0.001) and management system (P = 0.001). Thus, age group over four (OR = 7.9) and animal with poor management system (OR = 4.1) had a higher odds for tuberculin
reactivity compared to those with age group under four and cattle with good management system, respectively. Of the total
1,023 cattle subjected to postmortem examination, 11 (1.1%) were found to be positive for gross tuberculous lesions. Larger
proportion (50%) of TB lesion was recorded in the respiratory pathway followed by digestive system (28.6%) and prescapular
lymph nodes (21.4%). Of 14 tissue specimens collected from the gross lesions, four (28.6%) were positive for histopathological
TB lesions. In conclusion, this study revealed the importance of BTB in the study area in particular and the region in general. 相似文献
103.
Abattoir survey was conducted on 1,053 sheep and 639 goats slaughtered at Addis Ababa Abattoir, Ethiopia, between October
2007 and May 2008, with the objective to determine the prevalence of hydatidosis and assess the associated risk factors. Routine
meat inspection procedure was employed to detect the presence of the cyst in visceral organs (lung, liver, and omentum). Hydatid
cysts were found in 206 (19.94%) and 102 (16%) of the sheep and goats inspected, respectively. Statistically significant difference
in infection rates was noted between the two species. Likewise, there was significant difference in infection rates between
the two sexes and different age groups in both sheep and goats (P < 0.5). The study showed that hydatidosis is prevalent in Ethiopia. Thus, there is a need to introduce appropriate control
measures to minimize the rate of infection and reduce the ensuing economic losses. 相似文献
104.
Partitioning the respiratory components of soil surface CO2 efflux is important in understanding carbon turnover and in identifying the soil carbon sink/source function in response to land-use change. The sensitivities of soil respiration components on changing climate patterns are currently not fully understood. We used trench and isotopic methods to separate total soil respiration into autotrophic (R A ) and heterotrophic components (R H ). This study was undertaken on a Robinia pseudoacacia L. plantation in the southern Taihang Mountains, China. The fractionation of soil 13CO2 was analyzed by comparing the δ13C of soil CO2 extracted from buried steel tubes with results from Gas Vapor Probe Kits at a depth of 50 cm at the preliminary test (2.03‰). The results showed that the contribution of autotrophic respiration (fR A ) increased with increasing soil depth. The contribution of heterotrophic respiration (fR H ) declined with increasing soil depth. The contribution of autotrophic respiration was similar whether estimated by the trench method (fR A , 23.50%) or by the isotopic method in which a difference in value of 13C between soil and plant prevailed in the natural state (RC, 21.03%). The experimental error produced by the trench method was insignificant as compared with that produced by the isotopic method, providing a technical basis for further investigations. 相似文献
105.
Aklilu HA Almekinders CJ Udo HM Van der Zijpp AJ 《Tropical animal health and production》2007,39(3):165-177
This study aimed to examine village poultry consumption and marketing in Ethiopia in relation to gender, socio-cultural events
and market access. The main objects of the research were producers, poultry markets, producer-sellers, and intermediary sellers
in three locations representing different levels of market access in Tigray. About 3000 farm records were collected over a
period of 12 months from 131 producers to obtain quantitative data on sales and consumption. Ninety-three semi-structured
interviews with 58 producer-sellers and 35 intermediaries and 12 group discussions with these market actors were conducted
to explore organization, price dynamics and socio-cultural aspects of poultry marketing. In total, 928 producer-sellers and
225 intermediaries were monitored monthly to examine participation by gender in poultry marketing. Better market access was
associated with a shorter market chain and higher prices for the producers. Female-headed households had smaller poultry sales
and consumption per household but sale and consumption per family member were 25% and 66% higher, respectively, than in male-headed
households. While women dominated in the producer-sellers group, intermediaries were mainly men. Religious festivals periodically
shifted local demand and prices of poultry. To improve the benefit of poultry keeping, poverty-stricken households may profit
from better market access through better market information, infrastructure, market group formation and careful planning to
match the dynamics in demand. 相似文献
106.
The global dairy industry, the predominant pathogens causing mastitis, our understanding of mastitis pathogens and the host response to intramammary infection are changing rapidly. This paper aims to discuss changes in each of these aspects. Globalisation, energy demands, human population growth and climate change all affect the dairy industry. In many western countries, control programs for contagious mastitis have been in place for decades, resulting in a decrease in occurrence of Streptococcus agalactiae and Staphylococcus aureus mastitis and an increase in the relative impact of Streptococcus uberis and Escherichia coli mastitis. In some countries, Klebsiella spp. or Streptococcus dysgalactiae are appearing as important causes of mastitis. Differences between countries in legislation, veterinary and laboratory services and farmers' management practices affect the distribution and impact of mastitis pathogens. For pathogens that have traditionally been categorised as contagious, strain adaptation to human and bovine hosts has been recognised. For pathogens that are often categorised as environmental, strains causing transient and chronic infections are distinguished. The genetic basis underlying host adaptation and mechanisms of infection is being unravelled. Genomic information on pathogens and their hosts and improved knowledge of the host's innate and acquired immune responses to intramammary infections provide opportunities to expand our understanding of bovine mastitis. These developments will undoubtedly contribute to novel approaches to mastitis diagnostics and control. 相似文献
107.
Megan J. McLane DVM John W. Schlipf Jr. DVM MS Marco L. Margiocco DMV MS Howard Gelberg DVM PhD 《Journal of Veterinary Cardiology》2008,10(2):141-145
An alpaca presented for emergency evaluation of respiratory distress. Physical examination revealed weakness, pyrexia, and a grade V/VI left apical holosystolic murmur. Initial thoracic examination and radiographs were consistent with left sided congestive heart failure. Blood cultures, echocardiographic evaluation, and necropsy findings established a diagnosis of bacterial endocarditis associated with a Listeria monocytogenes infection. Left ventricular endocarditis is uncommon in ruminants, and to the authors' knowledge there are no other reports of L. monocytogenes being the causative agent in an alpaca. 相似文献
108.
Cyanobacteria are important components of the lowland rice ecosystem. Therefore, it is important to examine the effect of
herbicides (commonly used against weeds of rice crop) on the performance of cyanobacteria. We studied the toxic effects of
three herbicides often used in rice field, viz. propanil, pretilachlor and glyphosate, on the performance traits of Anabaena fertilissima C.B. Rao. Pretilachlor [0–40 active ingredient (ai) mg/L] and glyphosate (0–80 ai mg/L) exhibited toxicity to A. fertilissima at higher doses than propanil (0–1.5 mg/L). Propanil had severe damaging effects on cellular characteristics of A. fertilissima when compared to pretilachlor or glyphosate. Propanil treatment of A. fertilissima resulted in the leakage of protoplast from the heterocyst due to the breakage of the plasma membrane and surrounding wall.
Our study shows that photosystem II herbicides such as propanil could have deleterious effects on phototrophic (cyanobacterial)
communities, which are an integral part of the rice ecosystem. 相似文献
109.
Meherzia Mokni Mohamed Amri Ferid Limam Ezzedine Aouani 《Tropical animal health and production》2017,49(1):131-137
In the present study, we investigated the effect of grape seed and skin supplement (GSSS), on lactating dairy ewes’ production. Ten dairy pregnant ewes from northern Tunisia were allocated to two groups: control diet (C) and supplemented with 20 % (w/w) GSSS. The experiment lasted for 8 weeks and took place after 2 months of lambing. During the experiment, daily milk yield and milk composition were determined. Supplementation of the diet with GSSS increased milk production (P?<?0.001), calcium (P?<?0.01), free iron (P?<?0.01) and urea content (P?<?0.001) but had no effect on milk fat nor protein. From these data, it is concluded that the inclusion of GSSS in sheep diets increased significantly ewes’ milk yield. 相似文献
110.
Reza Ghanbarpour Nasrin Askari Masoud Ghorbanpour Yahya Tahamtan Khoobyar Mashayekhi Narjes Afsharipour Nasim Darijani 《Tropical animal health and production》2017,49(3):591-597
The aim of the present study was to determine the analysis of virulence genes and antimicrobial profile of diarrheagenic Escherichia coli isolated from diseased lambs. Two hundred ninety E. coli isolates were recovered from 300 rectal swabs of diarrheic lambs and were confirmed by biochemical tests. The pathotype determination was done according to the presence of genes including f5, f41, LTI, STI, bfp, ipaH, stx 1 , stx 2 , eae, ehlyA, cnf 1 , cnf 2 , cdIII, cdIV, and f17 by PCR method. Sixty-six isolates (23.72%) possessed the STI gene and categorized into entrotoxigenic E. coli (ETEC). Nine isolates (3.1%) and five isolates (1.72%) were positive for the cnf1 and cnf2 genes which categorized into necrotoxic E. coli (NTEC). Hundred and seventeen isolates (40.34%) harbored stx 1 and/or stx 2 and classified as Shiga toxin-producing E. coli (STEC). Thirteen isolates (4.48%) were assigned to atypical entropathogenic E. coli (aEPEC) and possessed eae gene. Two isolates (0.68%) were positive for ipaH gene and were assigned to entroinvasive E. coli (EIEC). Statistical analysis showed a specific association between eae gene and STEC pathotype (P?<?0.0001). The most prevalent resistance was observed against lincomycin (96.5%) and the lowest resistance was against kanamycine (56.02%), respectively. The high prevalence of STEC and ETEC indicates that diarrheic lambs represent an important reservoir for humans. ETEC may play an important role for frequent occurrence of diarrhea in lambs observed in this region. Due to high antibiotic resistance, appropriate control should be implemented in veterinary medicine to curb the development of novel resistant isolates. 相似文献