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排序方式: 共有1392条查询结果,搜索用时 15 毫秒
961.
C Campillo Serrano R Díaz Martínez M Romero J Villatoro A Nava A Reséndiz M E Parra L Sánchez J Cerrud 《Salud pública de México》1990,32(6):685-692
The life habits of 358 males abstemious (ABS) and 248 male risky or with harmful alcohol consumption (BRD) are compared; selected from the patients attending to a clinic of familiar medicine, of the Instituto Mexicano del Seguro Social (IMSS) and to General Hospital of the Secretaria de Salubridad y Asistencia (SSA). BRD are different from ABS because of a sedentary life, tobacco consumption, higher frequency of other drug use, poor nutrition, over weighted and poor physical condition. The difference between ABS and BRD is not only due to the alcohol consumption and related problems, but two groups of individuals with different ways of life. The present paper shows the first Mexican results of an International Multicentric Investigation coordinated by World Health Organization (WHO). 相似文献
962.
S Algeri A De Luigi M G De Simoni L Imeri M Marconi S Nava C Perego G Sacchetti 《Pharmacology, biochemistry, and behavior》1988,29(4):823-826
The effects of the anxiolytic drug buspirone and its metabolite 1-PP on the dopaminergic system were investigated. A single buspirone administration was found to decrease DA levels and increase its metabolite DOPAC in striatal samples. The levels of the other DA metabolite, 3MT, were unaffected; however its formation rate after inhibition of its metabolism, was found to be increased by buspirone. 1-PP did not affect either DOPAC or 3MT levels and formation. Striatal microdialysis showed that buspirone enhances DA release. In vivo voltammetry indicates that the increase of DA metabolism is identical in the two sampled dopaminergic areas, striatum and nucleus accumbens. On the basis of the results obtained ex vivo and in vivo the multiple effect of buspirone on dopaminergic system is discussed. 相似文献
963.
Synaptic vesicles isolated from bovine cerebral cortex were found to contain alkaline phosphatase activity towards p-nitrophenylphosphate and a-naphthyl phosphate, but not towards pyridoxal phosphate. The enzyme had an apparent molecular weight of 125,000 and co-purified with the synaptic vesicles in parallel with the specific neurotransmitter content and with the loss of contaminating components, whereas the major phosphatase which was present in the brain homogenate, with an apparent molecular weight of 140,000 purified away.The optimal pH for the enzyme activity on p-nitrophenylphosphate was 9.8. At this pH the activity was 33.4 nmol/mg protein/min, and the apparent Km value was 0.31 ± 0.05mM. The pH dependency of the synaptic vesicle phosphatase activity towards p-nitrophenylphosphate differed from that of the Ca2+/Mg2+-dependent ATP hydrolysis by the synaptic vesicles. Upon mild digestion of lyzed vesicles with trypsin, phosphatase activity was reduced whereas the ATPase activity was retained suggesting that the phosphatase and the ATPase are two different enzymes. The phosphatase was reversibly inhibited by ethyleneglycol bis (aminoethyl ether) N,N′-tetraacetic acid (EGTA) and activity was restored by the addition of an equimolar amount of Ca2+. Magnesium ions could restore only 30% of the activity.The activity of the synaptic vesicle phosphatase was not affected by o-phenanthroline, zinc ion or by cAMP. Tetranitromethane inactivated the enzyme irreversibly, whereas phenylmethanesulfonylfluoride diisopropylfluorophosphate and p-hydroxy-mercurybenzoate inhibited the activity partially. The enzyme did not have a diesterase activity. Adenosine mono-, di- and triphosphate inhibited the p-nitrophenylphosphatase activity and were also hydrolyzed by the vesicle preparation. However, the different kinetic parameters obtained with the nucleotide as inhibitors or as substrates suggest that additional enzymes are involved in the hydrolysis of the adenine nucleotides in vesicle preparation. 相似文献
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967.
Longitudinal study of heart disease in a Jamaican rural population. 3. Factors influencing changes in serial electrocardiograms 总被引:1,自引:0,他引:1
W E Miall E Del Campo J Fodor J R Nava Rhode L Ruiz K L Standard 《Bulletin of the World Health Organization》1972,46(6):695-708
A longitudinal survey of heart disease in adults in a representative rural population in Jamaica provided an opportunity to study factors influencing the progression and incidence of electrocardiographic abnormalities in serial tracings taken at a 5-year interval. An analysis of changes occurring in those with ECG abnormalities compatible with ischaemia at the first survey showed that progression from a less severe to a more severe category was greater in men than in women, in hypertensive than in normotensive subjects, and, among men, in those with the amplitude criteria of left ventricular hypertrophy. The incidence of abnormal Q/QS patterns was greater in men than in women, and that of all abnormalities suggesting ischaemia was greater in hypertensive than in normotensive persons; in men, it was greater in those with high amplitude R waves. The incidence cases showed S—T and T wave abnormalities, the great majority of which were classified as showing features compatible with ischaemia rather than with strain secondary to hypertrophy. These findings, which are discussed in terms of their possible causes, seem to confirm that much of the heart disease in this Jamaican community has features of myocardial ischaemia despite other evidence that extramural coronary vessels tend to be spared from such severe occlusive atheromatous disease as is found in many other populations. 相似文献
968.
Lene Symes PhD RN John Maddoux MA Judith McFarlane DrPH FAAN Angeles Nava PhD Heidi Gilroy MS 《Journal of clinical nursing》2014,23(19-20):2909-2918
969.