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991.
992.
993.
Forty-four multiparous and 43 primiparous Holstein cows were used to study the effect of dietary alfalfa silage: grain ratio on digestion, passage of digesta, and energy balance in a complete lactation experiment. Cows were placed on one of five treatments with forage contents from 38.2 to 98.2% (DM basis) during the first 12 wk of lactation. Forage content was increased during wk 13 to 26 of lactation to give diets containing 48.2 to 98.2% forage and again during wk 27 to 44 to give diets containing 68.2 to 98.2% forage. Both DMI and DM digestibilities decreased as proportion of dietary forage increased. The DM digestibilities for multiparous and primiparous cows ranged between 69.3 and 57.3% during early lactation and 64.9 and 55.5% during late lactation. Increased percentage of forage in the diet decreased and then increased (quadratic relationship) the ruminal retention time of La, a marker applied to the alfalfa silage in early and late lactation. Time cows spent eating and ruminating per kilogram of DMI increased as proportion of forage in the diet increased. Cows fed diets with a high proportion of alfalfa silage remained in negative energy balance longer than cows fed high grain diets. Intake of NEL (calculated by either of two methods) minus NEL output (milk, maintenance, and BW change) resulted in net balances of NEL after 36 wk of lactation within 5% of NEL intake and indicated that estimates of the NEL value of feedstuffs used in this experiment were reasonably accurate.  相似文献   
994.
One hundred patients sustained gunshot wounds involving bone but not joint with a low-velocity bullet. Soft-tissue involvement was less than 1 cm at its greatest diameter. All patients were free from artery or nerve damage. No formal fixation of fracture was required. The results of the study suggest that patients need not be hospitalized longer than 2 days after an extra-articular, low-velocity gunshot wound that violates the cortex. In addition, through the use of long half-life antibiotics, such as ceftriaxone, the length of hospitalization may further be reduced to a day, while the potential for morbidity from infection is not increased.  相似文献   
995.
A standardized elderberry extract, Sambucol (SAM), reduced hemagglutination and inhibited replication of human influenza viruses type A/Shangdong 9/93 (H3N2), A/Beijing 32/92 (H3N2), A/Texas 36/91 (H1N1), A/Singapore 6/86 (H1N1), type B/Panama 45/90, B/Yamagata 16/88, B/Ann Arbor 1/86, and of animal strains from Northern European swine and turkeys, A/Sw/Ger 2/81, A/Tur/Ger 3/91, and A/Sw/Ger 8533/91 in Madin-Darby canine kidney cells. A placebo-controlled, double blind study was carried out on a group of individuals living in an agricultural community (kibbutz) during an outbreak of influenza B/Panama in 1993. Fever, feeling of improvement, and complete cure were recorded during 6 days. Sera obtained in the acute and convalescent phases were tested for the presence of antibodies to influenza A, B, respiratory syncytial, and adenoviruses. Convalescent phase serologies showed higher mean and mean geometric hemagglutination inhibition (HI) titers to influenza B in the group treated with SAM than in the control group. A significant improvement of the symptoms, including fever, was seen in 93.3% of the cases in the SAM-treated group within 2 days, whereas in the control group 91.7% of the patients showed an improvement within 6 days (p < 0.001). A complete cure was achieved within 2 to 3 days in nearly 90% of the SAM-treated group and within at least 6 days in the placebo group (p < 0.001). No satisfactory medication to cure influenza type A and B is available. Considering the efficacy of the extract in vitro on all strains of influenza virus tested, the clinical results, its low cost, and absence of side-effects, this preparation could offer a possibility for safe treatment for influenza A and B.  相似文献   
996.
997.
Aspects of the metabolism and health of 63 cows which had been treated with different amounts of bovine somatotrophin (BST) daily in the preceding lactation and 25 control cows were studied. The aims of the study were first, to identify cows with ketotic conditions, either by measurements of blood metabolite concentrations or by clinical observations, secondly, to evaluate the risk of such conditions in cows treated with BST in the preceding lactation, and thirdly, to examine the metabolic and production consequences of the ketotic conditions in an environment in which the cows' health, body condition and nutrition were closely observed. The cows were categorised objectively by the use of cluster analysis into non-ketotic cows and ketonaemic cows, on the basis of their plasma metabolite concentrations. Twelve of the control cows and none of the cows previously treated with BST were classified as ketonaemic. Similarly, nine of the control cows but only two of the cows previously treated with BST had clinical ketosis. Some, but not all, of the decrease in the risk of clinical ketosis was attributable to the lower body condition score of the cows previously treated with BST. The clinically ketotic cows had a greater risk of other illness in the first 10 days post partum than their herdmates, but the ketonaemic cows had a significantly lower risk of other disease in the first 10 days post partum. The ketonaemic control cows were significantly heavier than the non-ketotic control cows, but they maintained a higher dry matter intake than the latter cows, probably a key factor in reducing the risk of clinical ketosis.  相似文献   
998.
999.
Chondroma of the laryngeal cartilage is a rare, benign neoplasm which can manifest as a neck mass or, if situated within the airway, as slowly progressive obstruction, hoarseness or dyspnea. The most common location for chondroma is the posterior lamina of the cricoid cartilage; the next most common locations are the thyroid, arytenoid and epiglottic cartilages. Chondroma and low-grade chondrosarcoma are difficult to distinguish from one another histologically. Although chondrosarcoma reportedly recurs, local surgical excision without radical margins and with long-term clinical follow-up is recommended. We report one case of thyroid cartilage chondroma and include a review of radiologic studies and histopathologic analysis results. We also report a second case with severe airway obstruction caused by a large cricoid chondroma. A review of the English language biomedical literature on laryngeal chondroma is included.  相似文献   
1000.
Maximum lifespan has been one of the most common aging measures in comparative studies, while the Gompertz model has recently attracted both proponents and critics of its capacity to adequately describe the acceleration of mortality in the oldest age classes. The Gompertz demographic model describes age-dependent mortality rate acceleration and age-independent mortality using the parameters alpha and A, respectively. Evolutionary biologists have predominantly used average longevity in studies of aging. Little is known about the evolutionary relationships of these measures on the microevolutionary time scale. We have simultaneously compared Gompertz parameters, average longevity, and maximum longevity in 50 related populations of Drosophila melanogaster, many of which have been selected for postponed aging. Overall, these populations have differentiated significantly for the A and alpha parameter of the Gompertz equation, as well as average and maximum longevity. These indices of aging appear to measure the same genetic changes in aging. However, in some specific population comparisons, the relationships among these measures are more complex. In a second experiment, environmental manipulation of longevity had substantially different effects from genetic differentiation, with the A parameter accounting for changes in overall mortality. The adequacy of the maximum lifespan and the Gompertz equation as indices of aging in evolutionary studies is discussed.  相似文献   
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