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891.
Adenosine deaminase (ADA), an enzyme involved in purine metabolism, has been shown to be of clinical importance in several diseases in humans. To investigate whether ADA is of any clinical significance in cats, plasma adenosine deaminase (P-ADA) and T cell adenosine deaminase (T-ADA) activities were measured in feline immunodeficiency virus (FIV) negative and positive cats. The AIDS-related complex (ARC) group showed a significant elevation in P-ADA activity compared to the asymptomatic carrier (AC), and FIV-negative groups (P<0.005). T-ADA activity was significantly elevated in FIV-positive cats compared to the FIV-negative group (P<0.05) and this elevation was attributed to the increase in the ARC group (P<0.01). A correlation was found between P-ADA and T-ADA activities in the FIV-negative group. T-ADA activity and CD4(+)cell number showed a strong negative correlation in FIV-positive cats (P<0.0005). CD4(+) cell numbers were significantly reduced in the ARC group compared to the healthy controls (P<0.005). Our results showed that T-ADA is increased in FIV-positive cats during the ARC stage. These results also suggest that ADA may be an indicator of T cell activation in the ARC stage of FIV infection.  相似文献   
892.
The objective of the present study was to search for differences in the behavior, use of resources and the physical condition between dominant and subordinate birds in furnished cages. In total, 60 commercial White Leghorn layers were used. At the age of 54 weeks, these birds were divided into two groups. Each group consisted of six cages with four birds per cage and six cages with six birds per cage. The dominance hierarchy was measured, to identify the highest dominant bird and the lowest subordinate bird in the hierarchy of each furnished cage. Behavioral observations using scanning techniques at 10 min intervals were conducted on the birds at 57 and 67 weeks of age for 3 days, respectively. Their physical condition (bodyweight and claw length) was also measured. Dominant birds used the dust bath more (P < 0.1) and nest box less (P < 0.01) than subordinate birds did. The use of the nest box decreased for subordinate birds from 57 to 67 weeks of age (P < 0.05). The dominant birds performed aggression and exploring more frequently than the subordinate birds (P < 0.001 and P < 0.05, respectively). In the comfort behaviors, the dominant birds performed dust‐bathing, as well as the using the dust bath, more than subordinate birds did (P < 0.1). In their exploring behavior, including scratching and litter pecking, dominant birds performed both behaviors more frequently, as well as using the dust bath and dust‐bathing in it, than subordinate birds did (P < 0.1 and P < 0.05, respectively). Aggression decreased for dominant birds from 57 to 67 weeks of age. In contrast, eating (P < 0.1) as well as drinking (P < 0.1) and other comfort behaviors (P < 0.1) increased for subordinate birds from 57 to 67 weeks of age. There was no significant difference between dominant and subordinate birds in their physical conditions. In conclusion, dominant birds had priority to use the dust box compared with the subordinate birds in the furnished cages. Conversely, the subordinate birds stayed in the nest box more than the dominant birds did. In the furnished cages, equipping the nest box was important not only for the birds to perform nesting behavior, but also for the subordinate birds to use the facility as a refuge especially just after introduction to the cage.  相似文献   
893.
We investigated whether CIDR-based ovulation-synchronization protocols inhibit secretion of prostaglandin (PG) F2alpha from the uterus in the following luteal phase in non-cycling beef cows. Ten early (a month) postpartum non-cycling Japanese Black beef cows were treated with (1) Ovsynch (GnRH analogue on Day 0, PGF2alpha analogue on Day 7, and GnRH analogue on Day 9; n=3), (2) Ovsynch+CIDR (Ovsynch protocol plus a CIDR for 7 days from Day 0; n=4), or (3) estradiol benzoate (EB) Ovsynch+CIDR (EB on Day 0 in lieu of the first GnRH treatment followed by the Ovsynch+CIDR protocol; n=3). An oxytocin challenge was administered on Day 24 to examine uterine PGF2alpha secretion. Plasma concentrations of 13,14-dihydro-15-keto- PGF2alpha were lower at 30-120 min after oxytocin administration in the Ovsynch+CIDR group and 75 min after administration in the EB Ovsynch+CIDR group than in the Ovsynch group (P<0.05). Plasma progesterone concentrations were higher from Days 1 to 7 in the Ovsynch+CIDR group and from Days 1 to 5 in the EB Ovsynch+CIDR group than in the Ovsynch group (P<0.05). The progesterone concentrations were higher on Days 27 and 29 in both CIDR-treated groups than in the Ovsynch group (P<0.05). In conclusion, in non-cycling beef cows, CIDR-based ovulation-synchronization protocols inhibit uterine PGF2alpha secretion in the following luteal phase and prevent premature luteolysis as is seen with the Ovsynch protocol.  相似文献   
894.
ORP150 is a hypoxic stress-induced protein located in the endoplasmic reticulum. Transgenic mice overexpressing ORP150 (ORP-Tg) exhibit vacuolar degeneration in the heart. To determine whether vacuolization is present in skeletal muscle, we pathologically examined ORP-Tg mice. After 60 days of age, severe vacuolization was found in the soleus muscles of the hind legs of the ORP-Tg mice. Immunohistochemical staining of ORP150 revealed co-localization of ORP150 and vacuolization in the affected cells. Electron microscopy revealed a marked increase in the number of rough-surfaced endoplasmic reticula (rER) and distention of the cisterna. These findings suggest that overexpression of ORP150 causes accumulation of ORP150 in the rER, resulting in vacuolar degeneration in the skeletal muscle of ORP-Tg mice.  相似文献   
895.
Larvae of the raccoon roundworm, Baylisascaris procyonis (B. procyonis) are a known cause of cerebrospinal larva migrans in animals and humans. The present paper described details of the central nervous lesion in the rabbits (Oryctolagus cuniculus) affected with B. procyonis larva migrans in Japan. Clinically affected animals showed neurological signs including circling, torticollis, tremor of head, or ataxic gait. The most characteristic pathological alterations were large malacic lesions associated with an activated astroglial proliferation which was seen at the corpus medullare in the cerebellum including the cerebellar peduncle. Moreover, focal malacic lesions with perivascular cuffing and infiltration by lymphocytes and heterophiles were scattered everywhere throughout the brain. In these lesions or normal-appearing areas away from obvious lesions, ascarid larvae, about a maximum 65-75 micro m in diameter, were recognized. Other prominent features were minute lesions (we call them migration tract-like lesions) composed of lymphocytes, hemosiderin-laden macrophages and reactive astrocytes scattering throughout the cerebrum. In this study, we demonstrated ascarid larvae in only eight out of 23 animals diagnosed as B. procyonis larva migrans. Since it is not always possible to detect the larvae, the possibility of B. procyonis larva migrans must be given serious consideration to the characteristic lesions described above.  相似文献   
896.
Bovine mastitis is one of the most prevalent and costly diseases in the dairy industry. Lipid mediators are signaling molecules which coordinately and intricately modulate inflammation. They are produced from polyunsaturated fatty acids (PUFAs) in the cellular membrane via several enzymes including cyclooxygenase (COX) and lipoxygenase (LOX). In the present study, we performed comprehensive analysis of lipid production in milk obtained from clinical or subclinical mastitic cows using liquid chromatography/mass spectrometry. We detected 26, 24, and 40 kinds of lipid constantly in healthy, subclinical, and clinical mastitic milk, respectively. In clinical mastitic milk, the amount of a major n‐6 PUFA, arachidonic acid (AA), tended to increase, whereas amounts of major n‐3 PUFAs, eicosapentaenoic acid and docosahexaenoic acid, tended to decrease. The amounts of several AA‐derived lipids including COX‐catalyzed prostaglandin (PG) D2 and PGE2, and LOX‐catalyzed leukotriene (LT) B4 were increased in clinical mastitic milk. Although subclinical mastitic milk represented similar trend of lipid production to healthy milk, amounts of several lipids such as LTD4, 14,15‐dihydroxyeicosatrienoic acid, and 14‐epoxyeicosatrienoic acid changed. These findings would be helpful for better understanding of mastitis pathology and give us some insights to develop a new diagnostic and therapeutic strategy.  相似文献   
897.
898.
This study investigated the effects of changes in daily management on behavior of a solitary female elephant in a zoo. The activity budget and space utilization of the subject and the management changes were recorded for 1 year after the conspecific male died. The observation days could be categorized into five clusters (C1–C5) by the characteristic behavioral pattern of each day. C1 had the highest percentage of resting of all clusters, and was observed after the loss of the conspecific and the beginning of use of the indoor exhibition room at night. C2, which had the highest percentage of stereotypy of any cluster, was observed after the beginning of habituation to the indoor exhibition room. Also, when the time schedule of management was changed irregularly, the subject frequently exhibited stereotypic pacing (C2, C4). The subject tended to rest when exhibiting lameness in the left hind limb (C3). In C5, activity reached a high level when she could utilize a familiar place under a stable management schedule. These results indicate that management changes affected the mental stability of an elephant in the early stage of social isolation.  相似文献   
899.
In our previous study, we detected a QTL for the oleic acid percentage (C18:1) on BTA9 in Japanese Black cattle through a genome‐wide association study (GWAS). In this study, we performed whole‐genome resequencing on eight animals with higher and lower C18:1 to identify candidate polymorphisms for the QTL. A total of 39,658 polymorphisms were detected in the candidate region, which were narrowed to 1993 polymorphisms within 23 genes based on allele differences between the high and low C18:1 groups. We subsequently selected three candidate genes, that is, CYB5R4, MED23, and VNN1, among the 23 genes based on their function in fatty acid metabolism. In each candidate gene, three SNPs, that is, CYB5R4 c.*349G > T, MED23 c.3700G > A, and VNN1 c.197C > T, were selected as candidate SNPs to verify their effect on C18:1 in a Japanese Black cattle population (n = 889). The statistical analysis showed that these SNPs were significantly associated with C18:1 (p < 0.05), suggesting that they were candidates for the QTL. In conclusion, we successfully narrowed the candidates for the QTL by detecting possible polymorphisms located within the candidate region. It is expected that the responsible polymorphism can be identified by demonstrating their effect on the gene's function.  相似文献   
900.
OBJECTIVE: To establish a method of F-wave evaluation and to determine normative values of F-wave parameters, including F-wave conduction velocity, persistence, and amplitude for the tibial nerve in cats. ANIMALS: 30 clinically normal cats. PROCEDURES: F-waves elicited in the interosseous muscles by stimulation of the tibial nerve were recorded, and linear regression analyses of the shortest latency versus the length of the tibial nerve and the limb length were performed. F-wave persistence was calculated by dividing the number of recorded F-waves by the number of stimuli. RESULTS: The correlation coefficient between F-wave latency and nerve length was 0.92, and that between F-wave latency and limb length was 0.58. Mean +/- SD F-wave conduction velocity of the tibial nerve was calculated to be 97.1 +/- 5.0 m/s. Linear regression analysis yielded the regression equation as follows: F-wave latency (milliseconds) = 2.60 + (0.02 x nerve length [mm]). Mean F-wave persistence and amplitude were 98.7 +/- 2.3% and 1.01 +/- 0.62 mV, respectively. CONCLUSIONS AND CLINICAL RELEVANCE: Results indicated that nerve length should be used for nerve conduction studies of F-waves in felids. The regression equation for F-wave latency, conduction velocity, persistence, and amplitude may contribute to the diagnosis of nervous system diseases or injury in cats, such as trauma to the spinal cord or diabetic neuropathy.  相似文献   
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