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971.
Double-contrast cystography was performed simultaneously with cystometrography in 6 male and 6 female dogs. All dogs were continent, and results of urinalyses were normal. Initial radiographs were made following intravesical infusion of 0.88 ml of positive contrast medium/kg of body weight. Additional radiographs were made during infusion of CO2. The last radiographs were made at the time of detrusor reflex (11 dogs) or when intravesical pressure reached 50 cm H2O (1 female). An average of 34% (range, 11% to 67%) of bladder length was within the pelvic canal when only the positive contrast medium was infused into the bladders. By the end of CO2 infusion, the bladder neck was more cranially located in 5 of 6 males and in 5 of 6 females. On the last radiographs made, an average of 19% (range, 10% to 35%) of bladder length was within the pelvic canal in 3 of 6 males and in 4 of 6 females. The bladder neck was rounded in 10 of 12 dogs. Thus, it was concluded that previous reports associating pelvic urinary bladder with urinary incontinence and other urologic abnormalities are questionable.  相似文献   
972.
A dorsal surgical approach to the perineal area and rectum was made on 10 healthy, adult dogs. The rectococcygeal muscle was incised and the levator ani and external sphincter muscles were separated to the level of the caudal rectal nerve. All dogs were clinically normal throughout a 3 week postoperative observation period.  相似文献   
973.
Equine skeletal muscle was histologically and histochemically analyzed in orderto measure fiber composition. Well-sampled open muscle biopsies were obtained from the semitendinosus muscle in select yearling Thoroughbreds. Each biopsy was sectioned and stained for the Harris Hematoxylin and Eosin and the modified Gomori Trichrome in order to demonstrate the basic muscle fiber morphology delineating intra and extracellular elements. A thirdstain, CA++ activated myosin Adenosine Triphosphatase at pH 9.4 was used to differentiate between specific types on the basis of enzyme activities. Subsequent differentiation of Type I slow twitch and Type II fast twitch muscle fibers was assessed on the basisof staining intensity. The high predominance of Type II fast twitch fibers ranged from 85.1 to 100 % with a mean of 90.5 %. Racing records, as two- and three-year-olds, were monitored in order to qualitatively compare histochemical results with performance achievements. While caution must be exercised, results of this investigation suggested that it may be possible, at an early age to partially predict the potential of each horse to adapt to training and to compete successfully in races of varying distances.  相似文献   
974.
975.
Ear canal ablation combining bulla osteotomy and curettage was performed on 44 dogs (n = 72 ears). Indications for the procedure included one or more of the following: chronic nonresponsive otitis externa and/or media (n = 71), tumor in the horizontal portion of the ear canal (n = 1), failed lateral ear resection (n = 11), ossified auricular cartilages secondary to chronic otitis externa (n = 22), failed previous total ear canal ablation (n = 1), and otitis interna (n = 1). In 40 dogs, the surgery was successful in alleviating all clinical signs of otitis externa and media. During the immediate postoperative period, 2 dogs died of causes unrelated to otitis. Complications related to the surgery developed in 9 of the surviving 42 dogs. Ultimately, 95% (40 of the surviving 42) of the dogs were cured by use of this procedure. Surgery successfully resolved the original problems in 97% (66 of 68) of the surgically treated ears of these dogs.  相似文献   
976.
Adenoviral infection of the renal interstitium of a lamb   总被引:1,自引:0,他引:1  
  相似文献   
977.
One hundred fifty Se-deficient, pregnant, crossbred beef cows were assigned to 1 of 4 treatment groups: group A, Se-deficient control; group B, 1 Se bolus at 0 and 119 days; group C, 1 Se bolus at 0 days; and group D, 2 Se pellets at 0 days. The Se bolus is an osmotic pump designed to release 3 mg of Se/d into the reticulorumen. The Se pellets weight approximately 30 g and contain 10% elemental Se, which is liberated in the reticulorumen. The Se bolus is designed to provide Se supplementation for 120 days and the Se pellets provide supplementation for up to 18 months. Cattle were maintained on Se-deficient pasture or forages prepared from these pastures for the duration of the experiment. Blood samples were collected from cows prior to treatment (time 0) and at 28, 52, 119, and 220 days thereafter and analyzed for blood Se (BSe) concentration. Body weights were recorded at each sampling time. Blood Se concentration of cows from all supplemented groups were significantly (P less than 0.01) higher than control values at all sample dates after treatments began. By the end of the 220-day study, treatment group-B cattle had significantly (P less than 0.01) higher BSe concentrations than any other group. Body weights of treatment groups fluctuated throughout the study, but did not differ (P greater than 0.05) between groups. One cow and 6 calves born to cows during the experimental period died. Necropsy of 5 calves provided no evidence linking these deaths to treatments.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
978.
Three lambs were used in a repeated Latin square design to determine the influence of isoenergetic infusions of propionate or glucose on portal-drained visceral flux (PDV) of nutrients and concentrations of insulin, glucagon, growth hormone and prolactin. Lambs were fitted with appropriate catheters for blood sampling and maintained on total intragastric infusion of nutrients. Basal VFA, casein, mineral and vitamin infusions (isocaloric and isonitrogenous) were supplemented with an additional 22 +/- .5 kcal/h from propionate, glucose or a combination of propionate plus glucose. Ruminal fluid proportion and arterial blood concentration and PDV flux of propionate increased (P less than .10) by 17 mol/100 mol, .02 mM and 40 mmol/h, respectively, with infusion of an additional 61 mmol/h of propionate. Regression equations predicted that, on a net basis, 67% of ruminally infused propionate and 43% of abomasally infused glucose appeared in portal blood. Arterial L-lactate, beta-hydroxybutyrate and acetate concentrations, and beta-hydroxybutyrate flux were increased (P less than .10) by .34 mM, .20 mM, .50 mM and 4.2 mmol/h, respectively, with infusion of 33 mmol/h of added glucose. Net utilization of glucose by the PDV was approximately 4.4 mmol/h when no glucose was infused. Increased infusion of propionate resulted in a 22.2-micrograms/h increase in PDV flux of insulin (P less than .08) but had no effect on arterial insulin, glucagon and prolactin concentrations (P greater than .10). Arterial growth hormone increased by 3.8 ng/ml with increasing glucose infusion (P less than .08).(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
979.
Of 38 aborted ovine fetuses from 23 sheep flocks 29 C. fetus subsp. fetus and 22 C. jejuni were isolated and examined biochemically and serologically for heat-stable antigens. Serologic examinations were carried out by passive haemagglutination test. In case of C. fetus subsp. fetus strains alkaline antigen extraction was used. Antisera to two serogroups of C. fetus and to Penner serotype reference strains 1 to 60 were produced in rabbits. Abortion was caused in 18 (78.3%) flocks by C. fetus subsp. fetus and in 5 (21.7%) flocks by C. jejuni. Six C. fetus subsp. fetus strains grew well at both 43 and 25 degrees C. With one exception all C. fetus subsp. fetus were resistant, whereas all 29 C. fetus subsp. venerealis strains were sensitive to 30 micrograms/ml cefoxitin and cefamandole. These two cephalosporins can be used to differentiate the two subspecies of C. fetus. Passive haemagglutination test using alkaline antigen extraction is a proper method for the examination of heat-stable antigens of both C. fetus subspecies. Out of 24 C. fetus subsp. fetus strains 13 belonged to serogroup A(01), and 11 to serogroup B(02). C. jejuni strains examined belonged to Penner serogroup 1 (6 strains), to serogroup 5 (4 strains) and to serogroup 8 (4 strains).  相似文献   
980.
The effects of age, environmental temperature and relative humidity on the bacterial flora of the nose and trachea of calves were investigated by sequential sampling of three groups each of eight Friesian-Holstein male calves kept in three different environmental conditions. All calves were vaccinated with a live attenuated vaccine against infectious bovine rhinotracheitis (IBR) when they were 12 weeks old. Nasal and tracheal swabs were collected at 14-day intervals for bacteriological examinations. The upper respiratory tract of calves started to be colonized by various species of bacteria within the first day of life. Although they were born at different periods of the year, the calves in all three groups had similar bacterial loads in their noses and tracheas when they were 1 day old (P greater than 0.05). The total bacterial colony forming units (BCFU) were highly variable from calf to calf and from one time of sampling to another. Despite these variations, there were age-related increases in the total BCFU in nasal and tracheal swabs in all experiments. These increases were influenced by environmental temperature. Vaccination of the calves with a live IBR vaccine appeared to enhance the bacterial colonization of the upper respiratory tract.  相似文献   
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