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31.
ABSTRACT. The association of zinc and vitamin A levels was studied in liver of foetuses and infants which were stillborn or died of various causes between the age of 26 weeks of gestation up to 16 weeks post-partum. No correlation between zinc and vitamin A was observed ( r =0.07). Although smaller infants had more hepatic vitamin A than larger infants no significant difference was observed between these groups for liver zinc values. 相似文献
32.
LARS SMEDMAN GEIR GUNNLAUGSSON ERLING NORRBY MARIA CLOTILDE SILVA ROLF ZETTERSTRÖM 《Acta paediatrica (Oslo, Norway : 1992)》1988,77(6):885-889
ABSTRACT. One hundred and fourty-four children who either were already immune or had been successfully immunized against measles were reexamined after 16 months. All still had circulating Elisa antibodies at a clearly detectable level. Titres were higher in the group of children stated to have had measles prior to the immunization. None of the children had measles after immunization. Boostering by the wild virus may have occurred, whereas no evidence of a booster effect from the vaccine was found. About one third of the children were underweight. Plasmodium falciparum parasitaemia rate, and also its seasonality, varied with the location of the child's homestead. Even children exposed to mesoendemic P. falciparum malaria and moderate malnutrition can be successfully immunized with a conventional live attenuated measles vaccine from 8 months of age, which probably results in a lasting protection. 相似文献
33.
ISABEL HAGEL NEIL R. LYNCH MIREYA PÉREZ MARIA C.DI PRISCO REINA LÓPEZ EDWARD ROJAS 《Parasite immunology》1993,15(6):311-315
Infection by helminthic parasites can cause the polyclonal stimulation of IgE synthesis, possibly via an enhanced production of interleukin-4 (IL-4), and this has been suggested to influence the allergic reactivity of tropical populations where these parasites are endemic. We evaluated a group of urban slum children in Caracas, Venezuela, with a high prevalence of helminthic infection (70.8%), to establish the relationship between the elevated IgE levels (3696 IU/ml) induced by these parasites and various aspects of the allergic response. Although the absolute levels of IL-4 detected in the sera of these children were low (0.65 ± 0.20 ng/ml), a strong positive correlation (r = 0.78) was found between these and serum IgE. The cutaneous immediate hypersensitivity reactivity to extracts of common environmental allergens was relatively low (17.5% to house dust), although that to Ascaris extract was moderately high (49.4%). Significant inverse correlations were found between total IgE levels and the different skin test reaction diameters, including Ascaris. The positivity of Prausnitz-Kustner passive transfer tests was low in this group (34%), with a strong inverse correlation (r= -0.75) being found between this and total IgE levels. Significant inverse correlations were also found between total IgE levels and specific IgE antibody to environmental allergens, and to Ascaris antigen. We suggest that the polyclonal production of IgE stimulated by helminthic infection can suppress the allergic response to environmental and parasite allergens via both mast cell saturation and inhibition of specific IgE production. 相似文献
34.
ANTONIO MICHELUCCI LUIGI PADELETTI REA CHELUCCI ALESSANDRO MEZZANI MARIA C. PORCIANI FEDERICO CARUSO EMANUELE LEBRUN FRANCESCA BACCI MOIRA MARTELLI GIAN FRANCO GENSINI 《Pacing and clinical electrophysiology : PACE》1996,19(5):758-767
Signal-averaged P wave of 42 patients with lone paroxysmal atrial fibrillation (PAF) and 29 normal subjects (N) were recorded, using three orthogonal leads and analyzed in the time and frequency (entire P wave or a 100-ms segment ranging from 75 ms before to 25 ms after the end of P wave) domains. PAFs were divided into a group of 12 having ≥ 2 attacks a month (HF) and a group of 30 having ≤ 2 attacks a year (LF). Statistically significant differences were absent with regard to ages of PAF and N; ages of HF, LF, and N at the time of signal-averaged ECG; ages of HF and LF at the time of the first arrhythmic episode; and elapsed times from the first episode. Length of P wave and some frequency-domain parameters were found to be significantly correlated with age. PAF showed a significantly longer duration of P wave in the frontal plane using the time-domain analysis. Frequency analysis was found to be useful in evaluating the influence of attack frequency. HF showed significantly higher values of some frequency-domain parameters than LF and N, while the three groups did not differ for time-domain analysis. P wave duration and frequency content of the three orthogonal leads proved to be significantly different in PAF and N. Right and left atrial echocardiographic dimensions proved to be higher (even if within normal limits) in HF than in LF and N. Results suggest that frequency analysis should be performed on the entire P wave. 相似文献
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37.
MARIA SPATZ Z. M. RAP S. I. RAPOPORT I. KLATZO 《Neuropathology and applied neurobiology》1976,2(1):53-61
Intracarotid perfusion of hypertonic solutions of urea, NaCl or acetamide increased the brain uptake index (BUI) of glucose analogues by rabbit brain, while isotonic urea was without effect. Lactamide, whether isotonic or hypertonic, decreased the BUI of glucose analogues. The increased BUI produced by the other hypertonic solutions could be inhibited by unlabeled substrate, unlabeled glucose or by phloridzin, and may reflect stimulated carrier-mediated transport of monosaccharides into brain. Although the increases could also have been due to altered cerebral blood flow, radioautography showed no gross evidence of such alterations. The BUI of 2-2-deoxy-D-[1-14 C]glucose was decreased by intracarotid injection of 0.01mM HgCl2 , to the same level seen following maximal inhibition with unlabeled 2-deoxy-D-glucose, while 0.08mM HgCl2 gave BUI's above this level. The lower concentration of HgCl2 probably inhibited carrier-mediated monosaccharide transfer, while the higher concentration appeared to increase passive diffusion into the brain as well. 相似文献
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39.
MARIA LANGER A. MASALA S. ALAGNA S. RASSU G. MADEDDU A. SOLINAS L. CHIANDUSSI 《Clinical endocrinology》1981,14(2):189-192
Elevated plasma concentrations and abnormal secretory patterns of GH have been found in patients with cirrhosis of the liver. Displacement of brain dopaminergic monoamines by false ‘neurotransmitters’ produced in the gut has been postulated as a cause of encephalopathy. In this study basal GH plasma levels and their response to TRH and l -DOPA were determined in thirty-nine cirrhotic patients and fifteen controls. Eleven patients had evidence of encephalopathy (Group 1), twenty-eight did not (Group 2). Both basal levels and the mean peak response to TRH were significantly higher in the cirrhotic patients than in the controls (Group 3). Peak values were moderately, but not significantly, higher in Group 1 than in Group 2. The response to l -DOPA was considerably lower in the encephalopathic patients in comparison with the subjects of both Group 2 and Group 3. This finding is consistent with depletion of active ‘neurotransmitters’ in CNS. Our data fail to demonstrate clearly whether the paradoxical response to TRH can also be related to these abnormalities of monoamine metabolism in cirrhotics. 相似文献
40.
Progressive multifocal leukoencephalopathy: ultrastructural findings in two brain biopsies Cerebral biopsies from two patients with progressive multifocal leukoencephalopathy due to SV40 (Case 1) and JC viruses (Case 2) have been examined by light and electron microscopy. No features permitting the morphologic differentiation of the diseases caused by the two agents were found. In the first case, intranuclear viral inclusions were seen in satellite oligodendrocytes in the cerebral cortex as well as in oligodendrocytes in the white matter. In this case demyelination developed in the absence of an inflammatory response. Extensive oligodendrocyte proliferation was evident, and phagocytosed myelin debris was found in both oligodendrocytes and astrocytes. In the second case extensive perivascular and tissue infiltration with plasma cells and evidence of viral multiplication in astrocytes were found. Demyelination occurred in the absence of macrophages in the first case which supports the conclusion that the demyelination in PML is due to the cytolytic effect of the virus on oligodendrocytes and is not an immunopathologic process. 相似文献