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61.
62.
Institute of Experimental Cardiology, All-Union Cardiologic Scientific Center, Academy of Medical Sciences of the USSR, Moscow. (Presented by Academician of the Academy of Medical Sciences of the USSR V. N. Smirnov.) Translated from Byulleten's Éksperimental'noi Biologii i Meditsiny, Vol. 110, No. 7, pp. 34–36, July, 1990.  相似文献   
63.
Two unrelated adult sibling cases (36- and 32-year-old females) of Juvenile hyaline fibromatosis are presented. The parents of one of these patients were non-consanguineous but natives of a small Island, and one elder sister among four siblings was affected with the same disease. The parents of the other patient were consanguineous, and one other sibling suffered from the identical disease. Both patients presented with multiple subcutaneous nodules, which they had had since infancy, and had undergone numerous surgical excisions. Light microscopy examination of skin lesions from both patients showed identical histology; an abundance of a homogenous, amorphous, eosinophlllc extracellular matrix in which spindle-shaped cells were embedded. Electron microscopically, the spindle-shaped cells had hypertrophic Golgi apparatus and dilated, rough endoplasmlc reticulum. Fine flbrillar and granular material-filled structures, the contents of which were occasionally released into the extracellular matrix, were also seen, immunohistochemically, the spindle-shaped cells were vlmentin-positive but negative for α-smooth muscle actln and S-100 protein, and the hyaline ground substance was positive for type I and type III collagen but negative for type II and type IV collagen and tenascin. Matrix metalloprotelnase-1, -2, and -9, and tissue inhibitor of matrix metalloproteinase (TlMP)-2 was positive but TIMP-1 was negative. A review of 39 cases of juvenile hyaline fibromatosis In the literature is also presented. In summary, skin lesions may be the most outstanding symptoms of juvenile hyaline fibromatosis, but joint contracture and gingival hypertrophy precede the skin manifestation.  相似文献   
64.
Several growth factor ligand and receptor gene products havebeen shown to play roles during preimplantation mammalian development.Genes for insulin-like growth factors (IGFs), transforming growthfactors (TGFs), fibroblast growth factor (FGF), platelet-derivedgrowth factor (PDGF) and receptors for insulin, IGF, PDGF, TGFand epidermal growth factor (EGF) are expressed by early embryosof several species including mouse, rat, cow and sheep. Rolesof growth factors during early development have been demonstratedby addition of purified growth factors to culture medium orby molecular genetic techniques that interfere with gene expression.In this way, it has been shown that successful development ofthe blastocyst is dependent on the action of epidermal growthfactor (EGF) and leukaemia inhibitory factor (LIF). Recent experimentsshow that both LIF and EGF stimulate secretion of urokinase-typeplasminogen activator (uPA) and gelatinase B/ matrix metalloproteinase-9(MMP-9) in day 7 mouse blastocyst outgrowths. At the same time,tissue inhibitors of MMPs (TIMPs) are also expressed by embryonic,decidual and uterine tissues during the implantation process.It appears that LIF may act directly or indirectly, by inducingthe expression of other cytokines, to regulate the temporaland spatial production and activity of proteases and proteaseinhibitors to create a favourable environment for implantation.  相似文献   
65.
Cancer metastasis involves distinct steps that depend on complicated tumor–host interactions. The hematogenous dissemination of tumor cells may be facilitated by factors that promote the arrest and adherence of cancer cells in capillaries. We examined whether anti-tumor monoclonal immunoglobulin M (IgM) antibodies promoted the hematogenous dissemination of B16 melanoma cells in syngeneic mice. IgM monoclonal antibodies were generated that selectively bind to B16 melanoma cells as compared to syngeneic fibroblasts, lymphocytes or Lewis lung carcinoma cells. Incubation of B16-BL6 or B16-F0 melanoma cells with these IgM anti-tumor antibodies significantly increased the number of lung colonies as compared with control antibodies. Moreover, intraperitoneal injection of specific antibody also significantly increased lung colonization. All anti-tumor antibodies promoted the aggregation of B16 melanoma cells. A chemically generated immunoglobulin G (IgG)-like fragment of an anti-tumor IgM antibody displayed greatly reduced tumor aggregation and, in contrast to intact IgM, did not significantly increase lung colonization of B16 melanoma cells. Neither intact IgM nor the IgG-like fragment enhanced the in vitro invasiveness of B16 melanoma cells across Matrigel-coated membranes. Our results, therefore, suggest that besides their beneficial anti-tumor effects, anti-tumor IgM antibodies may also promote the hematogenous dissemination of cancer cells. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   
66.
Asero R 《Allergy》2001,56(9):916-917
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67.
观察20例急性脑梗塞,30例冠心病在微循环中微血栓的变化,同时检测血小板聚集率、D-2聚体。结果表明微血栓阳性组血小板聚集率、D-2聚体均高于微血栓阴性组。治疗后二组血小板聚集、D-2聚体明显减少。提示微血栓、D-2聚体及血小板聚集率可作为评定冠心病、脑梗塞病情变化的一种指标  相似文献   
68.
合成消旋丹参素(简称合成丹参素)及其衍生物(BLA、BLE)在体外实验和体内静脉注射时,对ADP诱导的家兔和大鼠血小板聚集性均有明显的抑制作用。BLK和BLE有较强的促进血小板解聚作用,而合成丹参素较弱。合成丹参索、BLA和BLE在体外实验时,无升高血小板内cAMP作用,反使其cAMP含量下降。提示合成丹参素及其衍生物对血小板功能的作用,不是通过提高cAMP水平;推测可能和抑制血栓素A_2(TXA_2)合成酶有关。  相似文献   
69.
Summary BAY m1099 (a 1-deoxynojirimycin derivative) is a glucose analogue which is an -glucosidase inhibitor. Its effects on post-prandial blood glucose and insulin levels was compared with a placebo in 12 healthy male volunteers (6 Blacks and 6 Whites). It produced a similar, significant depression of post-prandial blood glucose and insulin leveles when the groups were assessed separately and when the data were pooled. Although blood insulin levels in Whites were higher than in Blacks, as previously reported, the difference was not statistically significant and did not appear to influence the response to the drug. BAY 1099 produced no objective or subjective untoward effects and appears to warrant further investigation as an adjuvant to dietary control of diabetes mellitus.  相似文献   
70.
Summary Behavioural effects on dopaminergic transmission of a phenylindane derivative, Lu 19-005 [(±)-trans-3-(3,4-dichlorophenyl)-N-methyl-l-indanamine, HCl], with potent inhibitory effect on dopamine (DA), noradrenaline (NA) and serotonin (5-HT) uptake in rats and the effect on DA, NA and 5-HT activity in mice have been studied and compared with those of other known DA, NA and 5-HT uptake inhibitors with different selectivity ratios.Lu 19-005 induced stereotyped behaviour after parenteral and oral administration with a duration of action of more than 24 h. The stereotyped licking and biting induced by Lu 19-005 was antagonized by reserpine and cis(Z)-flupentixol, but not affected by prazosin, p-chlorophenylalanine and -methyl-p-tyrosine pretreatments. Metergoline slightly facilitated the onset of stereotypy. Lower doses of Lu 19-005 induced ipsilateral circling in unilaterally 6-hydroxy-DA-lesioned rats. Finally, Lu 19-005 antagonized the catalepsy induced by perphenazine. In mice, Lu 19-005 potentiated the apomorphine-induced gnawing, reversed tetrabenazine-induced ptosis and potentiated the behavioural effects of 5-HTP within a similar dose range.The effects of Lu 19-005 were compared with those of other reference compounds. Nomifensine had qualitatively similar effects in rats although of much shorter duration. In mice, nomifensine selectively reversed tetrabenazine-induced ptosis. Weaker effects in all test models were found with bupropion, LR 5182 and GBR 13.069, compounds with inhibitory effect on DA and NA uptake. The DA-, NA-and 5-HT-uptake inhibitor diclofensine, however, had no effect in rats except in the 6-hydroxy-DA-circling test and had low potency in mice. The specific 5-HT-and NA-uptake inhibitors citalopram and talsupram, respectively, were ineffective in all rat models. They selectively potentiated 5-HTP or reversed tetrabenazine0induced ptosis in mice, respectively, as expected according to their in vitro profile. These results indicate that effect on DA mechanisms are responsible for the behavioural activity of the test compounds in the rat models and that the circling model is the most sensitive. Since DA may be involved in some depressive states Lu 19-005 could be an attaactive new antidepressant as it combines the pharmacological profile of established antidepressants (effect on NA and/or 5-HT uptake) with equipotent activity on DA uptake.  相似文献   
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