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131.
Summary Intact cores of agricultural soil planted with Sorghum bicolor were treated with selective biocides or combinations of biocides to manipulate soil organisms. Half the replicates of each biocide treatment were also given N fertilizer. The plants were maintained in a greenhouse, where growth and nutrient content and soil-organism populations were monitored over 16 weeks.The plants responded strongly to fertilization, but showed weak and variable responses to the biocides, even though biocide treatments aimed at animal taxa effectively reduced their target groups. There were no strong interactions between faunal manipulations and fertilization, implying that there was little compensatory function of fauna in the absence of fertilizer. Conditions under which soil fauna are important in making mineral nutrients available to plants in the field need further investigation.  相似文献   
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Biodegradation of crude oil is often dependent on the population sizes and metabolic activity of hydrocarbon-degrading microorganisms in addition to nutrient supply. Fertilization with N and P and bioaugmentation of oil-contaminated soil with hydrocarbon-degrading microorganisms may serve to enhance oil biodegradation rates. Glasshouse experiments were conducted to determine the impacts of fertilization and commercial bioremediation products on crude oil biodegradation and on changes in nutrient concentrations and populations of hydrocarbon-degrading microorganisms in salt marsh mesocosms growing Spartina alterniflora. Experiments were conducted under continuously-flooded and alternately-flooded/drained conditions with and without N and P fertilization. MaxBac, a slow-release fertilizer, was applied at a rate of 100 kg N ha-1 and 20 kg P ha-1, while additional P was applied at 20 kg P ha-1. Commercial products failed to enhance total oil or total petroleum hydrocarbon (TPH) degradation under either continuously or alternately-flooded conditions. An average of 62% of TPH was degraded by 33 d under continuously-flooded conditions, while 59% was degraded by 41 d after oil application under alternately-flooded conditions. Products generally did not increase population sizes of heterotrophs orhydrocarbon-degrading microorganisms. Concentrations of NH4 + and P decreased during experimentation, and fertilization with N and P stimulated total oil and TPH degradation under continuously-flooded, but not under alternately-flooded conditions.  相似文献   
134.
Judith A.  Hudson  DVM  PhD  Susan T.  Finn-Bodner  DVM  MS  Joan R.  Coates  DVM  Donald C.  Sorjonen  DVM  MS  Stephen T.  Simpson  DVM  MS  James C.  Wright  DVM  PhD  Jan E.  Steiss  DVM  PhD  Nancy R.  Cox  DVM  PhD  Dana M.  Vaughn  DVM  PhD  Starr C.  Miller  BS  Scott A.  Brown  DVM  PhD  Phillip D.  Garrett  DVM  MS 《Veterinary radiology & ultrasound》1995,36(6):542-547
Doppler ultrasonography of the spinal cord was performed in 34 normal, anesthetized dogs following hemilaminectomy. This study was part of an investigation to evaluate the efficacy of a 21-aminosteroid compound and high dose methylprednisolone for the treatment of spinal cord trauma. Grey-scale images of the canine spinal cord were similar to those described for the spinal cord of people. Doppler waveforms of intraparenchymal spinal arteries exhibited high end diastolic blood flow velocities, indicating low resistance to flow. Doppler values (mean ± SD) for arteries immediately ventrolateral to the central canal were: Peak Systolic Velocity = 5.78 ± 2.5 cm/sec, Minimum Diastolic Velocity = 3.5 ± 1.62 cm/sec, Mean Velocity = 4.45 ± 1.96 cm/sec, Minimum Diastolic Velocity = 3.5 ± 1.62 cm/sec, Mean Velocity = 4.45 ± 1.96 cm/sec, Systolic/Diastolic ratio = 169 ± 0.19, Pulsatility Index = 0.53 ± 0.09, and Resistance Index = 0.4 ± 0.06.  相似文献   
135.
A 4-month-old male Labrador Retriever was presented for recurrent bouts of pulmonary edema associated with tachycardia. Initial physical examination and echocardiography were unremarkable, and the electrocardiogram revealed only an intraventricular conduction disturbance. Subsequent recordings showed paroxysmal supraventricular tachycardia (SVT) (340 beats/min), which consistently produced pulmonary edema. The supraventricular tachycardia was unresponsive to adenosine, esmolol, and propranolol; was variably and transiently responsive to various vagal maneuvers and precordial thumps; and was always responsive to IV diltiazem. Multiple life-threatening episodes of SVT occurred, however, despite the chronic administration of oral diltiazem, propranolol, and procainamide. Diastolic cardiac dysfunction was documented by Doppler echocardiography and was thought to contribute to the development of pulmonary edema. A subsequent electrophysiologic study confirmed the presence of an atrioventricular posteroseptal accessory pathway that participated in orthodromic reciprocating tachycardia. This pathway was determined to conduct only in the retrograde direction ("concealed accessory pathway"). Intraoperative IV procainamide titration terminated the arrhythmia, which could not be reinduced when procainamide blood concentration approximated 20 μg/dL. Increasing the oral procainamide dose to achieve such plasma concentrations was successful in eliminating orthodromic reciprocating tachycardia, preventing heart failure, and returning Doppler indices of diastolic function to normal.  相似文献   
136.
A seven-year-old, intact male dobermann with a four-week history of anorexia was diagnosed as having impaction of the caecum with inspissated faeces. Radiographic and histopathological findings revealed impaction of the caecum and a mild subacute locally extensive typhlitis. Typhlectomy was curative and no further problems have been reported.  相似文献   
137.
Samples for microbiological culture were collected from the uterus of bitches using transcervical uterine cannulation (31 samples, 23 bitches) and from the uterus, cervix and vagina post mortem (19 bitches) at all stages of the reproductive cycle. Samples were cultured for aerobic and anaerobic bacteria and for aerobic mycoplasmas. Bacteria were always found in the uterus during prooestrus and oestrus (12 positive in 12 cultures) and rarely at other stages of the reproductive cycle: during anoestrus (one in 14) and other stages (none in 24). When microorganisms were detected at three sites post mortem, those found in the cervix and vagina were always of the same species as those found in the uterus. In six out of 13 instances, microorganisms were found in the cervix or vagina when none were found in the uterus. The mean number of isolates, number of bacteria seen in uterine cytology and bacterial growth were greater (P < 0–005) during oestrus and pro-oestrus than at other stages. Bacteria isolated from the uterus, in order of frequency, were Escherichia coli, Haemophilus species, α-haemo-lytic streptococci, Corynebacterium species, Streptococcus canis, Alcaligenes faecalis, Bac-teroides species, Pasteurella species and Proteus mirabilis. No mycoplasmas were cultured from the samples. This study indicates that the uterus of the normal bitch has a uterine microflora during pro-oestrus and oestrus that is similar to that of the vagina and cervix.  相似文献   
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139.
Cytology of the canine reproductive system   总被引:2,自引:0,他引:2  
The methods for semen collection, its laboratory examination, and the interpretation of findings are presented in this article. The lack of comprehensive data for normal dogs and the lack of data associating actual percentages of spermatozoa with specific abnormalities with fertility or infertility are highlighted. Consequently, there is a need for standardization and completeness of semen examination procedures, especially in studies destined for publication. Collection and analysis of prostatic samples then is discussed, and the distinguishing cytological features of benign prostatic hyperplasia, prostatic adenocarcinoma, prostatis (including prostatic abscessation), and prostatic cysts are presented. This is followed by an assessment of the clinical usefulness of vaginal cytology, particularly to assist in the management of normal canine reproduction and in the diagnosis of reproductive disorders. The ways in which vaginal smears can facilitate the diagnosis of the stage of the estrous cycle and the diagnosis of abnormalities of the cycle and other disorders of reproduction are presented. Further consideration is given to its use to estimate the time of ovulation retrospectively and estimate the time of whelping prospectively. Finally, two specific diseases that can affect dogs and bitches are reviewed, namely, canine brucellosis and transmissible venereal tumor.  相似文献   
140.
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