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991.
We examined the time course of apparent motion and apparent displacement of a visual target, and also the horizontal deviation of apparent straight-ahead related to left-posterior neck-muscle vibration. In Experiment 1, eight observers verbally judged the apparent motion and displacement of a visual target for 60 s from prior to the vibration to after its offset. We found that rightward apparent motion was an almost identical in magnitude during the vibration and disappeared within 20 s after the vibration offset. In contrast, rightward apparent displacement gradually increased during the vibration, and was sustained over 40 s after the vibration offset. In Experiment 2, five observers manually pointed to the position of a visual point in the median plane; the mean pointed position in the vibration condition was found to deviate maximally 3 degrees to the right of the mean pointed position in the control condition. In Experiment 3, the same observers closed their eyes and pointed to the apparent straight-ahead; the mean pointed positions did not differ between the vibration and control conditions.  相似文献   
992.
An endogenous ligand of central-type benzodiazepine receptors (CBR), the endozepine octadecaneuropeptide (ODN), is a very potent inhibitor of food intake in rodents. Although endozepines have been localized and characterized in the trout hypothalamus, so far, the action of these neuropeptides on feeding behavior has never been investigated in fish. In the present study, we have examined the effect of i.c.v. administration of synthetic rat ODN, its C-terminal octapeptide (OP) and the head-to-tail cyclic analog cyclo(1-8)OP (cOP) on feeding behavior in the goldfish model. i.c.v. injection of graded doses of ODN (2.5-10 pmol/g body weight (BW)) induced a dose-dependent inhibition of food intake, a significant decrease in cumulative food intake during the 60-min period after feeding being observed at doses of 5 and 10 pmol/g BW. The inhibitory effect of a 10 pmol/g BW dose of ODN on food consumption (-39%) was mimicked by an equimolar dose of OP (-42%) and cOP (-53%). The food intake-suppressing activity of ODN (10 pmol/g BW) was not affected by pre-injection of the CBR antagonist flumazenil (200 pmol/g BW). In contrast, the anorexigenic effect of ODN (10 pmol/g BW) was totally suppressed by a selective antagonist of metabotropic endozepine receptors, cyclo(1-8)[dLeu(5)]OP. These data indicate that, in goldfish as in rodents, ODN is a potent inhibitor of food consumption, and that the anorexigenic effect of ODN is not mediated through CBR but through the metabotropic endozepine receptor.  相似文献   
993.
MK-801, a noncompetitive N-methyl-d-aspartate (NMDA) receptor antagonist, produces neurotoxicity in adult rodent brain, and causes schizophrenia-like psychosis and cognitive dysfunction. Since neuropeptides and neuropeptide-degrading enzymes play important roles in cognitive function, we examined whether or not MK-801-induced schizophrenia-like psychosis is co-related with the changes of these enzymes in rat brain regions. In the present study, we investigated the effect of systemic treatment with MK-801 (0.5mg/kg) on neuropeptide-degrading enzymes, prolyl oligopeptidase (POP) and thimet oligopeptidase (EP 24.15), and glial marker proteins GFAP and CD11b in rat brain regions. The levels of POP and EP 24.15 activities increased significantly three days after treatment with MK-801 in the posterior cingulate/retrosplenial cortices (PC/RSC). Since atypical neuroleptic clozapine but not typical neuroleptic haloperidol prevents the MK-801-induced schizophrenia-like symptoms, we further examined the pretreated effects of the neuroleptics. Clozapine, but not haloperidol, significantly attenuated MK-801-induced changes in the levels of the neuropeptide-degrading enzymes. Immunohistochemical studies on GFAP and CD11b showed the increase in the PC/RSC of MK-801-treated rat brain and the pretreatment with clozapine suppressed these changes. Double immunostain experiments of EP 24.15 and GFAP antibodies demonstrated some co-localization of the neuropeptidase with astrocytes. The present findings suggest that change of neuropeptidases in the brain is in part correlated with changes of glial cells, and may play an important role in the control of schizophrenia-like psychotic disorders.  相似文献   
994.
995.
A method for rapid determination of viral RNA sequences (RDV) was applied to homogenates of Aedes aegypti collected in Thailand in an area in which dengue fever (dengue hemorrhagic fever) is endemic, using the mosquito cell line C6/36. Nucleic acid sequences of dengue virus type 4 and cell fusing agent virus were detected. This RDV method has the potential to become a standard method for detection of both known and newly emerging, unknown mosquito-borne viruses.  相似文献   
996.
BACKGROUND: This study was conducted to elucidate the effects of raloxifeneon proliferation and apoptosis in cultured human uterine leiomyomacells. METHODS: The monolayer cultures were treated with graded concentrations(10–9, 10–8 and 10–7 M) of raloxifeneand 10–7 M 17-estradiol (E2). Cell viability, percentageof proliferating cell nuclear antigen (PCNA)-positive cells,percentage of terminal deoxynucleotidyl transferase-mediated2'-deoxyuridine 5'-triphosphate nick-end labelling (TUNEL)-positivecells and the expression of PCNA and Bcl-2 proteins were assessedby 3-(4,5-dimethylthiazol-2-yl)-5-(3-carboxymethoxylphenyl)-2-(4-sulphophenyl)-2H-tetrazolium assay, immunocytochemistry, TUNEL assay and western blotanalysis, respectively. RESULTS: Compared with untreated cultures, the number of viable culturedcells, percentage of PCNA-positive cells and PCNA protein expressionwere significantly decreased by treatment with 10–9 Mraloxifene, but increased by treatment with either 10–8 Mor 10–7 M raloxifene. In contrast, the percentageof TUNEL-positive cells was significantly increased and Bcl-2protein expression was significantly decreased by treatmentwith 10–9 M raloxifene, whereas they were not affectedby treatment with either 10–8 or 10–7 M raloxifene. CONCLUSIONS: In cultured leiomyoma cells, low concentration (10–9 M)of raloxifene may inhibit the growth of leiomyoma cells, whereashigh concentrations (10–8 M, 10–7 M) ofraloxifene may promote their growth.  相似文献   
997.
We re-evaluated the criteria for waist circumference to predict the accumulation of the components of metabolic syndrome. We used data for 3,185 Japanese, aged 20-79 years. Metabolic syndrome has recently been redefined by a new criterion in Japan, in which waist circumference cutoff points, i.e. 85 cm for men and 90 cm for women, are employed. Among the 3,185 Japanese considered in the present study, 335 men (26.8%) and 69 women (3.6%) were diagnosed as having metabolic syndrome. A cutoff point as a predictor for 2 or more components of metabolic syndrome was evaluated by sensitivity/specificity and a receiver operating characteristic (ROC) curve. The optimal point was estimated as being approximately 85 cm of waist circumference in men and 75 cm in women. We therefore recommend a cutoff value, 75 cm of waist circumference, for the criterion of metabolic syndrome in women.  相似文献   
998.
Myeloid sarcoma (MS) is a tumor mass of myeloblasts or immature myeloid cells occurring in an extramedullary site or in bone. The tumor mass may precede or occur concurrently with acute or chronic myeloid leukemia or with other types of myeloproliferative disorders or myelodysplastic syndromes. MS is a rare disease, estimated to comprise between 2 to approximately 14% of acute myeloid leukemia. On the other hand, 95% of cases of CML have characteristic t (9;22) cytogenetic abnormality and BCR/ABL fusion gene at diagnosis. We here report the clinical significance of FISH in a diagnosis of MS that formed tumor in femur during the chronic phase of CML.  相似文献   
999.
Age-related cardiac disease model of Drosophila   总被引:4,自引:0,他引:4  
We have begun to study the genetic basis of deterioration of cardiac function in the fruit fly Drosophila melanogaster as an age-related cardiac disease model. For this purpose we have developed heart function assays in Drosophila and found that the fly's cardiac performance, as that of the human heart, deteriorates with age: aging fruit flies exhibit a progressive increase in electrical pacing-induced heart failure as well as in arrhythmias. The insulin receptor and associated pathways have a dramatic and heart-autonomous influence on age-related cardiac performance in flies, suggestive of potentially similar mechanisms in regulating cardiac aging in vertebrates. Compromised KCNQ and K(ATP) ion channel functions also seem to contribute to the decline in heart performance in aging flies, suggesting that the corresponding vertebrate gene functions may similarly decline with age, in addition to their conserved role in protecting against arrhythmias and hypoxia/ischemia, respectively. The fly heart is thus emerging as a promising genetic model for studying the age-dependent decline in organ function.  相似文献   
1000.
Tremendous progress in recent computer-controlled systems for fluorescence and laser-confocal microscopy has provided us with powerful tools to visualize and analyze molecular events in the cells. Various fluorescent staining and labeling techniques have also been developed to be used with these powerful instruments. Fluorescent proteins such as green fluorescent protein (GFP) allow us to directly label particular proteins of interest in living cells. This technique has been extended over a large area of cell biology, and a variety of fluorescent protein-derived techniques have been developed to visualize the functions and conditions of the molecules within living cells. In this review, we summarize the techniques for fluorescent staining and labeling for recent fluorescence microscopy.  相似文献   
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