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OBJECTIVE: To compare spectral and complexity characteristics of the EEG in a unique case of subcortical infarct to those seen in healthy controls. METHODS: Absolute and relative frequency spectra, theta/beta ratio, the brain symmetry index (BSI), Omega-complexity and synchronization likelihood were calculated of the EEG recorded in eyes closed and eyes open conditions. RESULTS: Increased absolute delta, theta, and Omega-complexity in these frequency bands, higher theta/beta ratios, and decreased relative beta activity were found in the side of the infarct. The BSI localized the excess of slow, and decrease of fast frequency activity to the area of ischemia. Following eyes opening the increase of fast and decrease of slow frequencies, the increase of Omega-complexity in the alpha and beta bands, and the decrease of synchronization likelihood for the fast frequency bands were reduced in the side of the infarct. CONCLUSIONS: The subcortical infarct caused ipsilaterally increased slow, and decreased fast frequency activity accompanied by decreased synchronization of slow, increased synchronization of fast frequencies. Reduced reactivity in the ischemic side was particularly apparent for complexity measures. SIGNIFICANCE: Complexity indices of the EEG are sensitive complementary measures of electrophysiological changes caused by local lesions such as subcortical stroke.  相似文献   
93.
Previously, we have demonstrated age-associated alterations in transmembrane signaling. One of the most reproducible alterations found in the immune response with aging is the decrease of lymphocyte proliferation on stimulation with various different mitogens. Here, we confirm that proliferative responses to stimulation with phytohaemagglutin (PHA), recombinant human IL-2, or anti-CD3 monoclonal antibody are all greater in the young (20-25 years) than old (60-87 years) population. We attempted to modulate the proliferative response using various agents acting at different levels of transmembrane signaling (pertussis toxin, cholera toxin, isoproterenol, PMA, Ca ionophore A23187), as well as at the level of the lymphocyte plasma membrane (methyl-beta-cyclodextrin, MBCD), or by using antioxidant vitamins (Vitamin E or C). None of these agents was able to restore effectively the proliferative response of lymphocytes from the aged to the level of young subjects. Even the combination of A23187 and PMA acting directly on calcium metabolism and protein kinase C activity was insufficient to restore the decreased mitogenic capacity of T cells from elderly subjects. Cyclodextrin, which decreases the cholesterol content of the membrane, increased the proliferative response of lymphocytes of elderly subjects, but not to the level of the young. Vitamin E had a very strong inhibitory effect on lymphocyte stimulation in both the age groups, except in combination with MBCD in T cells of the elderly, while Vitamin C had no significant modulatory effect. MAPK ERK and p38 activation was found to be decreased with aging in T cells after anti-CD3 mAb stimulation. Vitamin E but not Vitamin C strongly inhibited MAPK ERK or p38 activation. The direct activation of certain molecules or the modulation of the cholesterol content of the membrane seems to be effective immunomodulatory interventions with aging.  相似文献   
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Daytime and nocturnal intraocular pressure (IOP) values and systemic blood pressure (BP) values were compared in 60 non-glaucomatous controls, 54 glaucoma patients with normal visual field, and 46 glaucoma patients with visual field loss. The daytime IOP was measured with a Goldmann applanation tonometer and the nocturnal IOP with a Bio-Rad-Tono-Pen 2 . The BP was measured with either a mercury manometer or with a Meditech ABPM-02 Ambulatory Blood Pressure Monitor, which took BP readings at 60 minute intervals. A tendency towards increasing IOP and decreasing BP was detected in the non-glaucomatous controls, within normal limits, and pathological changes of IOP and BP were observed with a significantly high occurrence (5% > P > 2%; Pearson's 2-test) in the glaucoma group with visual field loss.  相似文献   
95.
Summary Biochemical and pharmacological studies suggest that the binding of [3H]mazindol is functionally related to the dopamine uptake carrier complex in rodent striatum. In order to study further the relationship between the substrate recognition site for dopamine uptake and the high-affinity binding site for mazindol the uptake of [3H]dopamine and the binding of [3H]mazindol was studied in BALB/cBy mouse striatum in various buffers (Tris, HEPES, bicarbonate-phosphate). Kinetic analysis showed that theK d, of the binding of [3H]mazindol and theK m of the uptake of [3Mdopamine was changed by different sodium concentrations and/or by the presence of Tris, while theB max, and theV max remained essentially the same. However, the shape of the Na+ dependency curves was not the same for mazindol binding and dopamine uptake in the various buffers. The inhibitory effect of other cations such as K+ and Tris was also different on binding and uptake under similar experimental circumstances. Dopamine did not slow down the dissociation of mazindol from its site and this effect was not sodium-sensitive. These complexities can be accomodated by a model that involves overlapping sites for mazindol and dopamine on the dopamine uptake carrier complex, and translocation -reorientation steps.Abbreviations K d dissociation rate constant - HEPES N-2hydroxyethyl-piperazine-N-2-ethanesulfonic acid - Km half-saturating concentration for uptake - B max maximal binding capacity - V max maximal initial uptake rate - k –1 dissociation rate constant - IC50 concentration of inhibitor causing 50% inhibition - DA 3,4dihydroxyphenylethylamine (dopamine) On leave from the Institute of Experimental Medicine, H-1450, Budapest, P.O.B. 67, Hungary. Send offprint request to I. Zimányi at her present address  相似文献   
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ObjectiveTo evaluate the factors associated with sunburns and with sun protection practice in Hungarian primary school children.MethodWe investigated children's (the median age: 8, range 5 to 12 years) and parents' assessment of sun sensitivity and sun protection characteristics in cities Gy?r and Zalaegerszeg (Hungary) in 2004. This cross-sectional study was part of a programme intended to increase children's and parents' awareness of harmful effects of excessive sunbathing. Analyses were based on 1804 multiple choice questionnaires.ResultsAt multivariate analysis a significant association between sunburns and fairness of complexion, freckles, use of sunscreens and T-shirts, and higher school-class level was observed. Sunburn was inversely associated with hat-wearing. Parents were more likely to apply sunscreen to children with light eyes and to the younger ones, to protect fair skinned children with T-shirts; to protect males and children with fair skin and light eyes with hats.ConclusionSince environmental factors play an important role in the development of skin cancer, morbidity could be reduced by primary prevention. Sun protection habits should therefore be taught early in life, and parents' behaviour adapted. Phenotype is not only related to sunburns but it also appears to influence parents' sun safety behaviour.  相似文献   
99.
In the present part of our series of papers a study on theophilline containing suppositories prepared in pharmacies is described. From the possible methods for assay of theophilline two nonaqueous titrations are compared. In first, theophilline is measured as a very weak base in a mixture of glacial acetic acid and acetic anhydride with perchloric acid using Sudan-III indicator, in second, the compound is measured as medium strong acid in dimethylformamide solvent with sodium-hydroxide titrant using phenolphtalein indicator. These methods were validated and the first was found more appropriate for regulatory control. We investigated suppositories prepared in our laboratory and in different pharmacies. The study revealed the poor quality of the preparations due to the difficulties in the technology and the importance of the applied vehicle. A guideline for the good preparation practice and an alternative technology are proposed.  相似文献   
100.
Molnár I 《Orvosi hetilap》2007,148(29):1347-1352
INTRODUCTION: Recent data supported the presence of T helper 2 dominance in the immune processes of Graves' disease and allergic diseases. A common role of regulatory T cells in the antigen- (or allergen-) specific immune responses was also demonstrated. AIMS: To study whether allergic events may play a role in the initiation or progression of autoimmune Graves' disease. The occurrence of seasonal allergy may explain the fluctuation in the onset of Graves' disease. METHODS: The presence of specific IgE levels against inhalative allergens was investigated in 327 patients with thyroid disease (Graves' disease, Hashimoto's thyroiditis, euthyroid goitre). Western blot method was used for the measurement of allergen-specific IgE levels with densitometric evaluation. RESULTS: Allergic sensitization was found in 88 cases (58%) for Graves' disease, 51 cases (46%) for Hashimoto's thyroiditis and 31 cases (55%) for euthyroid goitre. According to allergens, significant difference was demonstrated by Penicillium notatum, Dermatophagoides farinae, alder - rye (pollens) between Graves' disease (depending ophthalmopathy) and euthyroid goitre. In the four groups based on allergen seasonality, the month of the onset in Graves' disease was associated with the season of early tree and mugwort allergy (P < 0.019 between Graves' disease and Hashimoto's thyroiditis). The number of cases, in whom the onset of Graves' disease in a given month was similar to the month of allergic season, was 17 cases vs 7 cases with Hashimoto's thyroiditis (P < 0.028). CONCLUSIONS: The allergic sensitization was more frequent in Graves' disease, and the allergic seasonality may explain the fluctuation in the onset of Graves' disease.  相似文献   
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