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81.
Shawn‐Elizabeth Maloney Firdous A. Khan Tracy S. Chenier Mariana Diel de Amorim Michael Anthony Hayes Elizabeth L. Scholtz 《Reproduction in domestic animals》2019,54(3):473-479
Proteomic analysis of mare uterine flush fluid provides a minimally invasive technique for studying protein changes associated with the oestrous cycle. The aim of this study was to identify differentially abundant proteins in the uterine flush fluid of mares in oestrus and dioestrus. In this study, uterine flush fluid samples were collected from eight reproductively healthy mares in either oestrus (n = 5) or dioestrus (n = 3). Proteomic analysis was performed using liquid chromatography‐tandem mass spectrometry. Of 172 proteins identified, six proteins (immunoglobulin lambda‐like polypeptide 1, haemoglobin subunit alpha, alpha‐1B‐glycoprotein, serotransferrin, apolipoprotein A‐1, and haemoglobin subunit beta) were significantly more abundant in oestrus. These proteins may contribute to the endometrial defence system through roles in inflammation, immunity or antimicrobial activity. In other species, some of these proteins have been described as immunoglobulins, negative acute phase proteins or defence agents against micro‐organisms. During dioestrus, immunoglobulin alpha‐1 chain C region‐related, complement factor I, CD 109 antigen and uterocalin, were significantly more abundant. Research in other species suggests that these four proteins contribute to the immune response through proposed immunoregulatory characteristics, complement system involvement or roles in B cell–T cell interactions. In conclusion, ten differentially abundant proteins were identified in the uterine flush fluid of mares in oestrus and dioestrus. Targeted studies on these proteins could elucidate their role in uterine defence mechanisms during the oestrous cycle in the mare. 相似文献
82.
Daniel E. Goszczynski Anna C. Denicol Pablo J. Ross 《Reproduction in domestic animals》2019,54(Z4):22-31
In vitro gamete differentiation could revolutionize animal production by decreasing generation intervals, increasing the number of gametes per animal and facilitating the dissemination of elite genetics. In addition, it could help to develop new strategies for the conservation of endangered species. The recent in vitro reconstitution of germ cell development in mice has inspired researchers to invest their best efforts into reproducing this achievement in livestock species. With this goal in mind, multiple differentiation approaches and cell sources have been evaluated. The degree of success in these evaluations varies according to the species and the stage of development studied, but, in general, partially positive results have been obtained. Evidence suggests that although functional gametes with true reproductive potential are still to be obtained, it is a matter of time before this goal is achieved. 相似文献
83.
84.
The early diagnosis of bovine leukosis virus (BLV) infection, the aetiological agent in enzootic bovine leukosis, is important for the implementation of control measures. BLV infection is currently assessed by the detection of circulating antibodies against the viral envelope protein, gp51. However, this approach has shortcomings in the time taken to detect anti-BLV antibodies (three to four weeks after infection), and in the failure to detect antibodies in some animals. Clearly a technique such as the polymerase chain reaction (PCR), which directly detects the presence of viral DNA, has advantages over methods designed to measure host antibodies. The use of PCR for the detection of proviral DNA in an affected DNA sample with as little as 10(-5) micrograms of host DNA using agarose gel electrophoresis followed by ethidium bromide staining is described here. It was possible to improve the sensitivity of this assay by using hybridisation analysis with a BLV gene probe. PCR used in combination with hybridisation analysis will provide a sensitive diagnostic assay to detect BLV when antibody tests give weakly positive or equivocal results. 相似文献
85.
In order to assess age-related changes in the immune status of Labrador retriever dogs, leukocyte phenotypes, lymphocyte proliferative capacity, and serum antibody levels were measured in four cohorts of dogs, ranging from 2 to 10 years of age. Absolute numbers of white blood cells, lymphocytes, monocytes, granulocytes, and CD3+, CD4+, CD8+ and CD21+ lymphocytes significantly decreased with increasing age. Relative percentages of lymphocytes and CD4 cells were significantly decreased, and relative percentages of granulocytes and CD8 cells significantly increased, with age. The CD4:CD8 ratio showed a significant age-related decrease. Proliferative responses of T-cells to mitogens in whole-blood cultures either increased (Concanavalin A) or remained the same (phytohemagglutinin) with age when data was normalised to allow for differences in responding cell number. Similarly, normalised data of proliferative response to anti-CD3 stimulation together with phorbol 12-myristate 13-acetate showed an age-related increase. Serum levels of total IgA significantly increased with age whereas total IgG levels remained unchanged. These observations illustrate a significant change to a number of immune parameters with age. However, further work is required to determine whether the differences reported here are sufficient to cause overt or functional immune senescence in Labrador retriever dogs. 相似文献
86.
R. C. W. Daniel D. O'boyle † M. S. Marek A. J. Frost † 《Australian veterinary journal》1982,58(4):143-147
SUMMARY A survey of clinical mastitis in 26 South-East Queensland dairy herds supplying more than 300,000 litres of milk annually, revealed a quarter incidence of 2.6% with a cow incidence of 9% over a 3-month period. Secretion samples from cows yielded Staphylococcus aureus, Streptococcus agalactiae, Streptococcus dysgalactiae, Streptococcus uberis, coliforms, Pseudomonas spp and other bacteria in 38.5%, 12.5%, 6.6%, 3.4%, 2.6%. 0.6% and 2.0% of cases respectively. Samples from 38% of the cases were culturally negative while at least 38% of the clinical quarters had shown a previous clinical episode of mastitis. There was a significant association (P < 0.025) between herd and the likelihood of a negative culture result on samples from clinical cases. Twenty-one percent of cases occurred in the first month of lactation and 10.3% in the first week. There was a significant association (P < 0.005) between the age of cow and the stage of lactation in which clinical cases occurred in that cows in the 2 to 5 year age group were more likely to suffer attacks in the earlier part of lactation. There was a highly significant relationship (P < 0.005) between cow age group and the proportion of affected quarters and it was calculated that the change with each year of age was a 55% increase over the previous year. Forty-five percent of the isolates of S. aureus were resistant to penicillin. 相似文献
87.
Marcy J. Souza Nancy S. Johnstone-McLean Daniel Ward Kimberly Newkirk† 《Veterinary ophthalmology》2009,12(1):53-55
A 17-year-old female blue and gold macaw ( Ara ararauna ) presented for evaluation of a discreet, conjunctival mass of the OD. No other abnormalities were found on ophthalmic or physical examination. A heterophilic leukocytosis was present on the complete blood count, and elevated aspartate aminotransferase activity, creatinine kinase activity and cholesterol were present on the plasma biochemistry panel. Surgical removal of the mass was complete and no recurrence has occurred by six months after excision. Reduction of dietary fats was recommended to reduce serum cholesterol levels and reduce the likelihood of future occurrence of xanthomas in this bird. 相似文献
88.
加拿大安达略省家禽生产者对死禽处理通常有以下几种方法:选择经认证的死畜禽处理公司,坑埋,焚烧,堆肥.本文描述了使用堆肥法成功堆肥家禽屠体的一些关键因素. 堆肥是一个狭长的可被生物降解的有机物质堆,有很大的表面积以便氧气良好地渗透.堆肥通过需氧微生物分解生物有机物质制成一个稳定的、类似土壤的物质,称为腐殖质.为了刺激微生物快速降解,有必要给这些生长增殖的微生物提供最理想的环境. 相似文献
89.
Sita S. Withers Katherine A. Skorupski Daniel York Jin W. Choi Kevin D. Woolard Renee Laufer‐Amorim Ellen E. Sparger Carlos O. Rodriguez Stephen J. McSorley Arta M. Monjazeb William J. Murphy Robert J. Canter Robert B. Rebhun 《Veterinary and comparative oncology》2019,17(1):49-60
Immunotherapeutic strategies have shown promise for the treatment of canine osteosarcoma (cOSA). Very little is known about the immune microenvironment within cOSA, however, limiting our ability to identify potential immune targets and biomarkers of therapeutic response. We therefore prospectively assessed the disease‐free interval (DFI) and overall survival time (ST) of 30 dogs with cOSA treated with amputation and six doses of adjuvant carboplatin. We then quantified lymphocytic (CD3+, FOXP3+) and macrophage (CD204+) infiltrates within the primary tumours of this cohort using immunohistochemistry, and evaluated their association with outcome. Overall, the median DFI and ST were 392 and 455 days, respectively. The median number of CD3+ and FOXP3+ infiltrates were 45.8 cells/mm2 (4.6‐607.6 cells/mm2) and 8.5 mm2 (0‐163.1 cells/mm2), respectively. The median area of CD204+ macrophages was 4.7% (1.3%‐23.3%), and dogs with tumours containing greater than 4.7% CD204+ macrophages experienced a significantly longer DFI (P = 0.016). Interestingly, a significantly lower percentage of CD204+ macrophages was detected in cOSA arising from the proximal humerus compared to other appendicular bone locations (P = 0.016). Lymphocytic infiltrates did not appear to correlate with outcome in cOSA. Overall, our findings suggest that macrophages may play a role in inhibiting cOSA progression, as has been suggested in human osteosarcoma. 相似文献
90.
John M David Sandra Duarte Vogel Kimberly Longo Daniel Sanchez Gregory Lawson 《Veterinary anaesthesia and analgesia》2014,41(6):654-659
ObjectiveTo investigate a topical local anesthesia technique as a means to prevent and/or diminish pain in mice in a laboratory setting associated with tail vein injections performed by personnel in training.Study designProspective, randomized experimental trial.AnimalsThirty six adult female, 23–28 g CD-1 mice from an in-house training colony. They were acclimated to routine training and handling classes.MethodsEutectic mixture of local anesthetics (EMLA) cream (2.5% lidocaine/2.5% prilocaine) or a bland ointment control (n = 18) was applied on the tail prior to intravenous injection. The injections were performed by novices, who had never attempted the procedure, and experienced personnel. All participants were blinded to treatment groups. Three injection attempts were allowed per animal. The mice were observed and scored by blinded evaluators for behavioral and physiological changes, including respiratory rate, vocalization, tail flick, and escape behaviors, during and after the injection.ResultsThis study demonstrates that aversive behaviors induced by lateral tail vein injection were not changed by the preemptive application of EMLA cream. The aversive behaviors associated with lateral tail vein injection were significantly affected by the number of injection attempts and the individual's experience level.Conclusions and clinical relevanceTopical EMLA cream did not reduce signs of aversive reaction to tail vein injection and thus we did not find support for its use in mouse training programs for tail vein injections. 相似文献