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101.
PROBLEM: Early pregnancy factor (EPF) has been detected in pregnant bovine serum, and its activity appeared from 24 to 48 hr after insemination. However, in bovine in vitro fertilization (IVF), an EPF-like substance(s) had been detected in the culture medium of fertilized ovum. Therefore, we think that EPF and EPF-like substance(s) are very important materials for the development of the embryo. In this study, we examined the development of the embryo when fertilized bovine ova were cultured with IVF culture medium supplemented with EPF-positive or -negative serum. METHOD OF STUDY: EPF activity of each serum (fetal calf serum [FCS], calf serum [CS], estrus bovine serum, and pregnant bovine serum) was assessed by the bovine-rosette inhibition test. The sera were supplemented in TCM-199 culture medium, and IVF bovine ova were cultured with the media for 6 or 7 days, respectively. The culture media of each group were evaluated for EPF activity by the bovine-rosette inhibition test 48 hr after IVF. The cleavage rate of each group was calculated at 48 hr, and 6 or 7 days after IVF. The culture medium of cumulus cells was also tested for EPF activity. RESULTS: Only the pregnant bovine sera were EPF positive. All the culture media 48 hr after IVF became EPF positive. Additionally, the culture medium of cumulus cells did not have EPF activity. There was no significant difference in the cleavage rate of the EPF-positive and - negative sera 48 hr after IVF. However, the cleavage rate of EPF-positive sera tended to be higher than the negative sera. In contrast, the blastocyst development rates of EPF-positive sera were significantly higher than those of the negative sera 6 to 7 days after IVF (P < 0.05). CONCLUSIONS: The data suggest that an EPF-like substance(s) may be secreted from the in vitro fertilized bovine ovum but not from the cumulus cell, and that the EPF in the pregnant serum may accelerate the development of the bovine embryo in IVF.  相似文献   
102.
Summary This report concerns the postnatal expression of calcineurin (CaN) in rat striatum. For this purpose an immunohistochemical procedure was used. In neonatal striatum CaN immunoreactivity was found in discrete patches composed of many immature cells. With development there was an increase in staining intensity and in the proportion of positively reacting cells. CaN expression and localization in the striatum of 22–25 day old rats were similar to those of adult animals.  相似文献   
103.
Interleukin 6 (IL-6) production from synovial tissues of various diseases was examined. Augmented IL-6 production was found in inflammatory synovium not only in RA but also in other kinds of synovitis, including psoriatic arthritis and Beh?et's disease. Increased amounts of IL-6-mRNA were detected in rheumatoid synovium using a dot blot hydridization technique. Furthermore, there was a positive correlation between IL-6 production and accumulation of plasma cells in the synovium. These findings suggest that IL-6 plays an important role not only in immune response but also in active inflammation in various kinds of synovitis.  相似文献   
104.
The interaction between oxidized low-density lipoprotein (LDL) and macrophages are known to be important in the development of arteriosclerosis. Macrophages take up oxidized LDL, becoming foam cells, which contribute to the thickening of the blood vessel wall. The antioxidant properties of polyphenols found in vegetables and other foods have been shown to have a protective effect against arteriosclerosis. To elucidate the effect of flavonoids from fruits, vegetables and cereals on oxidized LDL uptake in macrophages, the inhibitory activity of various flavonoids on DiI-ac-LDL uptake reaction in mouse macrophage cell line J774.1 was measured. We found significant uptake of DiI-ac-LDL, but not DiI-LDL, into the J774.1 cells. In addition, polyinosin and dextran sulphate inhibited uptake, but apigenin, kaempferol, and naringenin, did not. Isoflavones and resveratrol significantly inhibit uptake of DiI-ac-LDL into macrophages, and have a protective effect against arteriosclerosis.  相似文献   
105.
Postlesional reorganization of vestibular afferent and commissural inputs onto second-order vestibular neurons was studied in the isolated brain after unilateral section of the N.VIII, of the ramus anterior (RA) of N.VIII, of the utricular (UT) or of the anterior vertical and horizontal canal nerves in combination. RA nerve section eliminated the inputs from utricular, anterior vertical and horizontal canal organs. In the first set of experiments we recorded field potentials on the operated side of the vestibular nuclei 2 months after RA nerve section. These responses were evoked by electrical stimulation of the RA nerve or of the posterior vertical canal nerve on the operated or on the intact side. The amplitudes of afferent field potentials evoked by stimulation of the spared posterior vertical canal nerve were increased. The amplitudes of afferent field potentials evoked by stimulation of the axotomized RA nerve remained unaltered. After N.VIII section the commissural, but not the afferent, field potentials increased significantly on the operated side following stimulation of N.VIII on the intact and on the operated side, respectively. After UT nerve section no change in commissural but an increase in the amplitude of afferent field potentials from each of the three intact canal nerves was observed on the operated side. In the context of earlier results these findings imply that second-order vestibular neurons, disfacilitated due to afferent nerve section, became receptive to additional, excitatory synaptic inputs, preferentially from intact vestibular nerve afferent fibers. The reduced excitation via afferent nerve inputs was thereby replaced by other afferent nerve inputs from spatially inadequate vestibular end-organs. The synaptic terminals of inactivated afferent nerve fibers were maintained and not repressed. The process of central reorganization after vestibular nerve lesion was activity related, the expansion of signals restricted to inputs from intact fibers, its extent graded and its onset delayed with respect to the onset of corresponding spinal changes and to the onset of postural recovery after the same type of nerve lesion. After the section of RA nerve or of an individual nerve branch the labyrinthine end-organs remained intact and were not removed as after unilateral labyrinthectomy (UL). Peripheral reinnervation of the end-organs was thus excluded after UL, but expected after one of the former types of lesion. Functional reinnervation of the utricular macula was mirrored behaviorally by the reappearance of severe postural deficits following a second RA nerve section. These lesion-induced postural deficits began to reappear if the repeated RA nerve section was delayed with respect to the first by about 3 months. We therefore studied postlesional reorganization in the brainstem 3 months after the first RA nerve section. Reinnervation of the utricular macula was accompanied by a rapid decline of the increased amplitudes of afferent and commissural vestibular field potentials towards control values, suggesting the reversibility of the lesion-induced central reorganization. Electronic Publication  相似文献   
106.
Intracellular Abeta was examined in both a neuronal cell line (B103) expressing human APP with Swedish mutation and a non-neuronal cell line (Chinese hamster ovary, CHO) expressing wild human APP. Exposure of the APP695sw-transfected B103 cells to okadaic acid for 3 h, Abeta immunostaining was enhanced, as demonstrated by two independent anti-Abeta antibodies. The confocal microscopic study revealed that the immunoreactivity of Abeta was mainly colocalized with a Golgi marker and partially with an ER marker. Quantitative analyses, using Abeta sandwich ELISA, showed significantly increased intracellular Abeta. False positive detection of Abeta by antibody cross-reaction with APP was ruled out by extracting the fraction with formic acid and making it alkaline before subjecting it to ELISA. This procedure resulted in a fraction that contained little APP. Using CHO cells, OA treatment was also shown to be effective in increasing Abeta, as demonstrated by Western blot. The increased full-length APP and decreased APPC99 were also observed. This is the first study to demonstrate that OA treatment significantly increases intracellular Abeta.  相似文献   
107.
108.
Objective and design:To determine the effect of FK506 (tacrolimus) on paw inflammation, TNF- expression in joint, and bone and cartilage destruction in type II collagen-induced arthritis (CIA) model in rats.Methods:CIA was induced by immunization of female Lewis rats with an emulsion of bovine type II collagen and incomplete Freunds adjuvant. Paw inflammation was assessed by the increase in paw volume. Tumor necrosis factor (TNF) - expression in hind knee joint was assessed by immunohistochemical analysis. Lesions of bone and cartilage were assessed on the basis of histological change in knee joint, radiographic analysis in hind paw, bone mineral density in femora and proteoglycan contents in the cartilage of femoral heads. FK506 at doses of 1, 1.8 and 3.2 mg/kg or its placebo formulation was orally administered to rats for 28 days from the day after immunization (n = 10). Effect of FK506 was compared with that of vehicle (distilled water).Results:FK506 at a dose of 1.8 mg/kg significantly suppressed paw swelling (p < 0.01) and histological change in knee joint (p < 0.05). Tumor necrosis factor (TNF)- was mainly expressed in the region with a marked infiltration of inflammatory cells in the hind knee joint. FK506 (3.2 mg/kg) markedly reduced TNF- expression. FK506 at a dose of 1.8 mg/kg suppressed radiographic changes in hind paw (p < 0.05) and also recovered the decrease in bone mineral density in the femora (p < 0.05). Proteoglycan contents in the cartilage of femoral heads were determined to evaluate the cartilage destruction more quantitatively and found to significantly decrease in CIA rats. FK506 at a dose of 1.8 mg/kg recovered the loss of proteoglycan contents (p < 0.01).Conclusion:These results show that FK506 is effective in suppressing inflammation, TNF- expression in joint, and damage to bone and cartilage in rat CIA, and may be useful in the treatment of rheumatoid arthritis.  相似文献   
109.
110.
In cultured rat hippocampal neurons, overexpression of Homer1a/Vesl-1S, an inducible protein upregulated by seizure or long-term potentiation, caused a reduction of punctate distribution of a postsynaptic protein Homer1c/Vesl-1L, without significant decrease in its total amount. Clusters of F-actin were also decreased. Treatments of cells with BDNF or a proteasome inhibitor, which cause increase in the expression level of endogenous Homer1a, also resulted in the reduction of Homer1c puncta. These results indicate that the accumulation of Homer1a, either exogenously expressed or endogenously induced, caused redistribution and dispersion of postsynaptic clusters of Homer1c and F-actin, suggesting an important role of Homer1a in synaptic remodeling.  相似文献   
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