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981.
Streptococcus suis is an important pathogen in the swine industry. This study is the first to report on the antimicrobial susceptibility of S. suis isolated from clinically healthy pigs in Brazil; the fourth major pork producer in the world. The antimicrobial susceptibility of 260 strains was determined by disc diffusion method. Strains were commonly susceptible to ceftiofur, cephalexin, chloramphenicol, and florfenicol, with more than 80% of the strains being susceptible to these antimicrobials. A high frequency of resistance to some of the antimicrobial agents was demonstrated, with resistance being most common to sulfa-trimethoprim (100%), tetracycline (97.69%), clindamycin (84.61%), norfloxacin (76.92%), and ciprofloxacin (61.15%). A high percentage of multidrug resistant strains (99.61%) were also found. The results of this study indicate that ceftiofur, cephalexin, and florfenicol are the antimicrobials of choice for empirical control of the infections caused by S. suis.  相似文献   
982.
Host–pathogen epidemiological processes are often unclear due both to their complexity and over-simplistic approaches used to quantify them. We applied a multi-event capture–recapture procedure on two years of data from three rabbit populations to test hypotheses about the effects on survival of, and the dynamics of host immunity to, both myxoma virus and Rabbit Hemorrhagic Disease Virus (MV and RHDV). Although the populations shared the same climatic and management conditions, MV and RHDV dynamics varied greatly among them; MV and RHDV seroprevalences were positively related to density in one population, but RHDV seroprevalence was negatively related to density in another. In addition, (i) juvenile survival was most often negatively related to seropositivity, (ii) RHDV seropositives never had considerably higher survival, and (iii) seroconversion to seropositivity was more likely than the reverse. We suggest seropositivity affects survival depending on trade-offs among antibody protection, immunosuppression and virus lethality. Negative effects of seropositivity might be greater on juveniles due to their immature immune system. Also, while RHDV directly affects survival through the hemorrhagic syndrome, MV lack of direct lethal effects means that interactions influencing survival are likely to be more complex. Multi-event modeling allowed us to quantify patterns of host–pathogen dynamics otherwise difficult to discern. Such an approach offers a promising tool to shed light on causative mechanisms.  相似文献   
983.
Background: A mutation in the sarcomeric gene coding for the myosin-binding protein C gene has been identified in a colony of Maine Coon cats with hypertrophic cardiomyopathy (MyBPC3-A31P mutation). However, the close correlation between genotype and phenotype (left ventricular hypertrophy [LVH] and dysfunction) has never been assessed in a large population, particularly in heterozygous (Hetero) cats.
Objectives: To investigate LV morphology and function with echocardiography and tissue Doppler imaging (TDI) in a population of Maine Coon cats tested for the MyBPC3-A31P mutation with focus on Hetero animals.
Animals: Ninety-six Maine Coon cats.
Methods: Prospective observational study. Cats were screened for the MyBPC3-A31P mutation and examined with both echocardiography and 2-dimensional color TDI.
Results: Fifty-two out of 96 cats did not have the mutation (wild-type genotype, Homo WT), 38/96 and 6/96 were Hetero- and homozygous-mutated (Homo M) cats, respectively. Only 11% of Hetero cats (4/38) had LVH and 29% (10/34) of Hetero cats without LVH were >4 years old (4.1–11.5 years). LVH was also detected in 2 Homo WT cats (4%). A significantly decreased ( P < .05) longitudinal E/A (ratio between early and late diastolic myocardial velocities) in the basal segment of the interventricular septum was observed in Hetero cats without LVH (n = 34) compared with Homo WT cats without LVH (n = 50), thus confirming that the Hetero status is associated with regional diastolic dysfunction ( P < .05).
Conclusions: The heterozygous status is not consistently associated with LVH and major myocardial dysfunction. Moreover, Homo WT cats can also develop LVH, suggesting that other genetic causes might be implicated.  相似文献   
984.
Persistent truncus arteriosus (PTA) was diagnosed in an 8-year-old neutered male Poodle referred for echocardiographic examination prior to anesthesia for surgical correction of bilateral cataract. A single large artery limited by a bicuspid valve and overriding both ventricles was observed with 2 distinct pulmonary arteries arising from the common arterial trunk. A large size interventricular septal defect was associated with a low velocity bidirectional shunt. The lesion was identified as a Type 3 PTA according to Collett and Edwards' classification. Although no clinical signs were reported, the dog presented polycythemia (packed cell volume = 68%) at the time of diagnosis. To our knowledge, this is the first report of an echocardiographic diagnosis of PTA in the dog. Until now, the ante-mortem diagnosis of this congenital heart disease has only been described in the cat. This case is also of interest because of the age of the animal and the total absence of cardio-respiratory signs at the time of diagnosis.  相似文献   
985.
Blanca Cacereña cattle is the most threatened Spanish bovine breed. Although a Conservation Plan, exists, the little reproductive success and some chromosome abnormality were observed in the breed making it advisable to extend the genetic basis of the animals opening up the recorded herd book to new animals from local farms. However, the crossing with meat breeds like Charolais cattle is used to improve the commercial product. We used 30 microsatellites to determine the Charolais genetic influence in the current herds by the identification of the hybrids and to recognize new “purebred” animals in the “Blanca Cacereña” population. Blood samples were taken from animals of Blanca Cacereña bovine breed (112 animals with pedigree and 68 without pedigree), Charolais breed (60 animals) as a breed used commercially in crosses with Blanca Cacereña, and Retinta breed (60 animals) as a reference population. STRUCTURE analyses were performed with or without prior population information to assign individuals to breed, identifying admixed individuals, and inferring their ancestry. We have found that 37/68 animals without pedigree were purebred. Our results will be useful to manage a conservation plan of the breed, preserving the characteristic genetic pool and avoiding its extinction.  相似文献   
986.
The effect of neutral detergent soluble fibre (NDSF) level on digestibility, fermentation traits, intestinal microbiota and performance was studied in weaned rabbits. A control diet (DA) containing 103 g NDSF/kg DM included dehydrated alfalfa as the main source of fibre. Another diet (B-AP) was formulated by replacing half of the dehydrated alfalfa with a mixture of beet and apple pulp resulting in 131 g NDSF/kg DM. A third diet (OH) was obtained by substituting half of the dehydrated alfalfa with a mix of oat hulls and a soybean protein concentrate and contained 79 g NDSF/kg DM. All diets contained similar levels of total fibre (NDSF + neutral detergent fibre), starch and protein (446, 208, and 199 g/kg DM, respectively). Forty-two rabbits (14/diet) weaned at 25 days were used to determine faecal digestibility from 32 to 35 days of age. This group, plus another nine rabbits/diet (23/diet), were used to determine weight of stomach and caecum and their contents, caecal fermentation traits and similarity rate (SR) of intestinal microbiota. Another 105 and 245 weaned rabbits were used to determine growth traits and mortality, respectively. From 25 to 39 days of age, rabbits were fed the experimental diets and from 39 to 60 days they were fed a commercial diet, including robenidine hydrochloride in all diets. Drinking water was supplemented with apramicine sulfate and tylosine tartrate throughout the experimental period. Faecal and energy digestibility increased linearly by 8% and NDF digestibility by 43% between extreme diets with NDSF inclusion (P < 0.001). Weight of total gastrointestinal tract decreased linearly and quadratically with NDSF reduction (P = 0.008 and P = 0.089, respectively). Stomach pH decreased linearly with increasing levels of NDSF (P ≤ 0.041). Weight of caecal contents increased linearly between animals fed OH and B-AP diets (P < 0.001). Level of inclusion of NDSF had no effect (P ≥ 0.12) on pH, VFA concentration and VFA molar proportions in caecal contents. Treatments appeared to influence the SR of caecal microbiota but a lesser effect was observed on ileal microbiota. Post weaning feed efficiency (25–39 days) increased linearly (P < 0.001) with NDSF inclusion by 10% between extreme diets, and by 3% in the whole fattening period (P = 0.027). Average feed intake during the post weaning (25–39 days) and the whole fattening period increased with NDSF reduction (P ≤ 0.079). No effect of NDSF was detected on average daily gain (P ≥ 0.15). Mortality decreased linearly with increasing levels of NDSF in the post weaning and in the whole fattening period (P = 0.086 and 0.016, respectively).  相似文献   
987.
988.
OBJECTIVE: To describe an anal approach for excision of primary rectal tumors in dogs and to report outcome. STUDY DESIGN: Retrospective study. ANIMALS: Dogs (n=23) with primary rectal tumors. METHODS: Review of medical records (1990-2000) of dogs with primary rectal neoplasia excised surgically using an anal approach with rectal prolapse. With dogs anesthetized, the rectum was prolapsed, stabilized with stay sutures during tumor excision with 1 cm margins to the level of the muscularis, then the rectal mucosa was sutured. RESULTS: Each dog had only 1 tumor type (adenocarcinoma [8], solitary polyp [5], carcinoma [4], plasmacytoma [2], adenoma [1], leiomyoma [1], mucinous carcinoma [1], and papilloma [1]). Mean tumor volume was 3.1 cm(3) (range 0.1-37.7 cm(3)). Postoperative complications (rectal bleeding [5], tenesmus [4]) were mild and resolved within 7 days after surgery; another dog had partial mucosal dehiscence identified at 6 days. The primary tumor was incompletely excised in 1 dog (4.3%), and local recurrence occurred 16 and 24 months after surgery in 2 dogs. Outcome beyond the immediate postoperative period was known for 18 dogs, including 2 dogs still alive. Mean postoperative disease-free interval for these 18 dogs was 36.8 months (range 5-84 months). CONCLUSION: Surgical excision of tumors of the caudal rectum can be accomplished through the anus after rectal prolapse. CLINICAL RELEVANCE: An anal approach facilitated by rectal prolapse should be considered as a viable option for the surgical treatment of selected cases of tumors of the caudal aspect of the rectum in dogs.  相似文献   
989.
990.
OBJECTIVE: To describe geographical differences and time trends in the supply of the most important food components of the traditional Mediterranean diet. DESIGN: Food supply data collected from national food balance sheets for the period 1961-2001. SETTING: Selected Mediterranean countries: Spain, Italy, France, Greece, Algeria, Morocco, Tunisia and Turkey. RESULTS: Differences of almost 30-fold and five-fold were found in the supply of olive oil and fruits and vegetables, respectively, among the Mediterranean countries studied during the 1960s. A favourable increasing trend for the supply of fruit and vegetables was observed in most Mediterranean countries. However, an increase in the supply of meats and dairy products and a decrease in the supply of cereals and wine were observed in European Mediterranean countries from 1961 until 2001. Only in African and Asiatic Mediterranean countries were cereals the base of food supply. During the 1990s, Greece's food supply pattern was closest to the traditional Mediterranean diet, while Italy and Spain maintained a high availability of fruits, vegetables and olive oil, but were losing the other typical components. Among African and Asiatic Mediterranean countries, only Turkey presented a traditional Mediterranean dietary pattern except with respect to olive oil, the supply of which was very low. France showed a Western dietary pattern, with a high supply of animal products and a low supply of olive oil. CONCLUSIONS: Dietary supplies in the Mediterranean area were quite heterogeneous in the 1960s and have experienced a process of Westernization, especially in European Mediterranean countries.  相似文献   
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