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991.
A. Ravi Raja G. N. Vishal Babu Geraldine Menezes T. Venkatesh 《Indian journal of clinical biochemistry : IJCB》2008,23(2):200-203
Awareness about the toxic effects of non-essential metals is still lacking in developing countries. Lead is one among them,
which ranks second in the Agency for Toxic Substances and Disease Registry’ s top 20 lists of toxic metals. Some of the herbal
medicines prepared from certain roots and leaves are known to contain this toxic metal at alarming levels. We have a case
of a person who suffered from the toxic effects of lead such as vomiting and colicky abdominal pain after consuming a herbal
remedy for Jaundice treatment. This went unrecognized initially because of the presence of multiple problems like Malaria
and Renal calculi. Lead poisoning as causative factor for anemia, vomiting and colic were confirmed only when blood lead concentration
was estimated. A combination of chelation therapy and nutritional supplementation was found to be useful in reducing the body
lead burden. 相似文献
992.
K. Devika Rani N. Suneetha Shruti Mohanty Pragna Rao 《Indian journal of clinical biochemistry : IJCB》2008,23(2):150-153
This study is conducted in chronic alcoholics to assess the association of an Individual’s level of serum homocysteine with
the success of achieving alcohol deaddiction in the patient. The patients’ nutrition status is also assessed. 50 chronic alcoholics
admitted to a deaddiction center were inducted into the study. Patients underwent an 8 weeks holistic program to promote rehabilitation
from alcoholism. All the patients were addicted to alcohol for 8 – 10 years. Of the 50 patients enrolled, 39 of them completed
the 8 weeks program including complete abstinence from alcohol during this period. Fasting blood samples were collected on
admission and again after 8 weeks of alcohol abstinence for analyses of serum homocysteine and serum prealbumin, transferrin,
total proteins and albumin, gammaglutamyl transferase (GGT) and alanine transaminase (ALT). Of the 50 patients enrolled in
the study, 39 completed the 8 weeks rehabilitation program. 11 patients discontinued within 2 weeks of admission. During the
8 weeks of complete alcohol abstinence, patients were given a balanced diet and multivitamin supplements. A significant improvement
in their nutritional status was noted by the elevation of serum levels of prealbumin, transferrin, total proteins and albumin.
Serum homocysteine levels decreased significantly (p<0.002) to normal levels from previous hyperhomocytenemia. This was accompanied
by decrease in serum GGT and ALT levels indicating improved liver functions. Serum estimation of homocysteine in chronic alcoholics
is important to assess whether the patient will have a successful rehabilitation. Normal homocysteine levels are achieved
after dietary changes and abstinence from alcohol. Timely correction of hyperhomocysteinemia also provides successful rehabilitation. 相似文献
993.
The paradoxical profession: Teaching at the turn of the century 总被引:1,自引:0,他引:1
994.
995.
This study tested the Adult Distance Study Through Computer Conferencing (ADSCC) model developed by Eastmond (1994), to determine if learner readiness, online features, and CMC‐related learning approaches are associated with learner satisfaction in an academic computer conference. All three variables were correlated with learner satisfaction and online features emerged as the best predictor of learner satisfaction. Results indicate interrelationships between the three variables. The ADSCC model was a good predictor of learner satisfaction. It provided a useful framework for understanding learner satisfaction by showing how to categorise the different components that influence satisfaction in an academic computer conference. 相似文献
996.
997.
To study the influence of negative or positive experience of the ingestion of ethanol in femaleDrosophila with thefast form of the Adh gene on the acceptance of a medium containing this substance as site for egg laying, flies raised on a medium without alcohol were kept (1) on a regular medium, (2) on a medium supplemented with ethanol, (3) on a medium supplemented with 4-methylpyrazole (4-MP, an inhibitor of the enzyme ADH), and (4) on a medium containing both ethanol and this inhibitor. Whereas theDrosophila exhibited no spontaneous egg-laying preference for ethanol, a preference was induced by the ingestion of this substance, which also led to an increase in the number of eggs laid. By contrast, ingestion of ethanol, associated with the inhibitor, reduced the number of eggs laid and led to an avoidance of ethanol-containing media. Flies treated with ethanol and 4-MP exhibited signs of sickness (reduction in locomotor activity and loss of balance). The egg-laying preference for the ethanol results from learning linked to the metabolic utilization of this alcohol. The adaptative significance of this learning is discussed. 相似文献
998.
In 1904, Prandtl proposed the concept of boundary layers that revolutionised the study of fluid mechanics. In this article we present the basic ideas of boundary layers and boundary-layer separation, a phenomenon that distinguishes streamlined from bluff bodies. 相似文献
999.
1000.
N. Valanides F. Gritsi M. Kampeza K. Ravanis 《International Journal of Early Years Education》2000,8(1):27-39
A semi-structured interview was individually administered to 33 children aged 5-6. The interview raised questions about the shapes of the Sun and the Earth as well as the cause of the day/night cycle. A teaching intervention designed to teach pre-school age children these concepts was then implemented with groups of 6-7 children. The intervention's effectiveness was consequently evaluated (after 2 weeks) using an interview similar to that conducted prior to the intervention. The results of the study showed that the majority of children readily accepted certain aspects of the scientific explanations of the day/night cycle. Specifically, the majority accepted that the Sun and the Earth are separate spherical objects, but fewer children attributed the day/night cycle to rotation of the Earth on its axis. Most seemed puzzled by the simultaneous movements of the Earth around the Sun and around its axis. Educational and research implications are discussed. Une semi-directive interview individuelle etait administree a 33 enfants de 5 a 6 ans. L'interview contenait des questions sur le scheme du soleil et de la terre et aussi sur la cause du cercle 'jour-nuit'. Une intervention didactique etait apres introduite aux groups de 6-7 enfants et ses resultats etaient finalement evalues, en utilisant la meme interview, deux semaines apres l'intervention. Les resultats de cet etude montrent que la majorite d'enfants ont accepte certains aspects des points de vue scientifiques concernant le cercle 'jour-nuit'. Plus specifiquement, la plupart d'enfants ont accepte que les schemes du soleil et de la terre ressemblaient a une sphere, mais moins d'enfants ont attribue le cercle 'jour-nuit' a la rotation de la terre autour du soi-meme. Quelques enfants n'ont pas developpe les correctes conceptions et c'etait apparent qu'ils avaient des difficultes a comprendre les mouvements simultanes de la terre autour du soleil et du soi-meme. Se administro individualmente una entrevista semiestructurada a 33 ninos de edades comprendidas entre los 5 y 6 anos. La entrevista incluja cuestiones sobre formas del sol y de la tierra y tambien la causa del ciclo dia/noche. Luego se introdujo una intervencion didactica a grupos de 6-7 ninos de edad preescolar para ensenarles estos conceptos. La efectividad de la intervencion file evaluada 2 semanas mas tarde, con una entrevista parecida a la realizada antes de la intervencion. Los resultados del estudjo mostraron que la mayoria de los ninos aceptaban facilmente ciertos aspectos de las explicaciones cientificas del ciclo dia/noche. Mas especialmente, la mayoria aceptaba que el sol y la tierra eran objetos esfericos diferentes, pero menos ninos atribuian el hecho de que el ciclo dia/noche se relacionara con la rotacion de la tierra alrededor de sil eje. Muchos parecian sorprenderse con los movimientos simultaneos de la tierra alrededor del sol y alrededor de si misma. Se discuten las implicaciones educativas y de investigacion. 相似文献