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61.
The aim of this study was to clarify the role of serum S100 beta on the accurate assessment of reversibility of brain damage after fulminant hepatic failure (FHF). Among the 13 patients with FHF enrolled in this study, 12 underwent living donor liver transplantation; one patient could not the procedure because of volvulus of the sigmoid colon. Serum S100 beta was serially measured using a chemiluminescent immunoassay. Preoperative serum S100 beta in patients with diffuse brain edema was significantly higher than that in patients with localized brain edema (P < 0.05). Patients with preoperative brain death showed serum S100 beta levels over 7.0 microg/L. Serum S100 beta levels correlated with the degree of brain edema of FHF. It has the potential to be a new clinical, noninvasive indicator of brain damage due to FHF.  相似文献   
62.
Dok-1 and Dok-2 are closely related rasGAP-associated docking proteins expressed preferentially in hematopoietic cells. Although they are phosphorylated upon activation of many protein tyrosine kinases (PTKs), including those coupled with cytokine receptors and oncogenic PTKs like Bcr-Abl, their physiological roles are largely unidentified. Here, we generated mice lacking Dok-1 and/or Dok-2, which included the double-deficient mice succumbed to myeloproliferative disease resembling human chronic myelogenous leukemia (CML) and chronic myelomonocytic leukemia. The double-deficient mice displayed medullary and extramedullary hyperplasia of granulocyte/macrophage progenitors with leukemic potential, and their myeloid cells showed hyperproliferation and hypo-apoptosis upon treatment and deprivation of cytokines, respectively. Consistently, the mutant myeloid cells showed enhanced Erk and Akt activation upon cytokine stimulation. Moreover, loss of Dok-1 and/or Dok-2 induced blastic transformation of chronic phase CML-like disease in mice carrying the bcr-abl gene, a cause of CML. These findings demonstrate that Dok-1 and Dok-2 are key negative regulators of cytokine responses and are essential for myeloid homeostasis and suppression of leukemia.  相似文献   
63.
The B cell antigen receptor (BCR)-mediated activation of IkappaB kinase (IKK) and nuclear factor-kappaB require protein kinase C (PKC)beta; however, the mechanism by which PKCbeta regulates IKK is unclear. Here, we demonstrate that another protein kinase, TGFbeta-activated kinase (TAK)1, is essential for IKK activation in response to BCR stimulation. TAK1 interacts with the phosphorylated CARMA1 (also known as caspase recruitment domain [CARD]11, Bimp3) and this interaction is mediated by PKCbeta. IKK is also recruited to the CARMA1-Bcl10-mucosal-associated lymphoid tissue 1 adaptor complex in a PKCbeta-dependent manner. Hence, our data suggest that phosphorylation of CARMA1, mediated by PKCbeta, brings two key protein kinases, TAK1 and IKK, into close proximity, thereby allowing TAK1 to phosphorylate IKK.  相似文献   
64.
65.
Src, a proto-oncogene, has been strongly implicated in the growth, progression and metastasis of a number of human cancers. Its role in lung cancer is, however, still unknown. In the present study, we assessed the expression of Src in three different human lung adenocarcinoma cell lines (PC-9, PC14PE6, A549), and explored the effect of a novel Src kinase inhibitor, M475271, on the behavior of the cell lines. The three cell lines expressed various levels of auto-phosphorylated Src. While M475271 reduced Src-phosphorylation and invasiveness of all three cell lines, it inhibited the proliferation of PC-9 and A549 cells with highly phosphorylated Src, but not PC14PE6 cells. We further examined the effect of M475271 on subcutaneous tumors and lung metastasis caused by PC-9 and/or A549 cells in NK-cell depleted SCID mice. Daily oral treatment with M475271 inhibited the growth of subcutaneous tumors with PC-9 and A549 cells via inhibition of tumor cells proliferation, VEGF production and/or vascularization in the mice in a dose-dependent manner. In the metastasis model with A549 cells, the lung weight in the M475271 (50 mg/kg)-treated group was less than that of the control group, despite no difference in the number of metastatic nodules. Our results suggest that inhibition of tyrosine kinase Src by M475271 could reduce the growth, invasion and VEGF-mediated neovascularization of lung adenocarcinoma cells, resulting in inhibition of growth of subcutaneous tumors and lung metastasis. Therefore, a novel Src tyrosine kinase inhibitor, M475271, might be helpful for controlling the progression of human lung adenocarcinoma.  相似文献   
66.
Adult Still's disease reflects a Th2 rather than a Th1 cytokine profile   总被引:2,自引:0,他引:2  
Adult Still's disease (ASD) is a chronic multisystemic disease. Extraordinarily high serum levels of IL-18 in ASD patients have been described, whereas the mechanism remains to be clarified. This study aimed to evaluate proinflammatory cytokines and to consider their pathological roles. In patients with rheumatic diseases (n = 151), blood samples were taken at the active phase and the serum levels of IL-18 and other proinflammatory cytokines were measured by ELISA. The extra-high levels of IL-18 were confirmed selectively in ASD patients (n = 10). In the active phase of ASD patients, the levels of IL-6 were elevated accordingly, but IL-1beta and TNF-alpha were undetectable. As to Th1-Th2 cytokines, the levels of IL-4 and IL-13, but not INF-gamma, IL-12, or IL-2, were elevated in all ASD patients examined. Moreover, the serum levels of IL-18 showed a good correlation with those of IL-4, suggesting that ASD reflects a Th2 rather than a Th1 cytokine profile.  相似文献   
67.
Summary Two polymorphic dinucleotide (CA) repeat clones were isolated from two P1 phage clones, 1239F3 and 8H11, and were localized to chromosome 8 using a panel of 13 mouse human somatic cell hybrids.  相似文献   
68.
The DNA sliding clamp is a multifunctional protein involved in cellular DNA transactions. In Archaea and Eukaryota, proliferating cell nuclear antigen (PCNA) is the sliding clamp. The ring‐shaped PCNA encircles double‐stranded DNA within its central hole and tethers other proteins on DNA. The majority of Crenarchaeota, a subdomain of Archaea, have multiple PCNA homologues, and they are capable of forming heterotrimeric rings for their functions. In contrast, most organisms in Euryarchaeota, the other major subdomain, have a single PCNA forming a homotrimeric ring structure. Among the Euryarchaeota whose genome is sequenced, Thermococcus kodakarensis is the only species with two genes encoding PCNA homologues on its genome. We cloned the two genes from the T. kodakarensis genome, and the gene products, PCNA1 and PCNA2, were characterized. PCNA1 stimulated the DNA synthesis reactions of the two DNA polymerases, PolB and PolD, from T. kodakarensis in vitro. PCNA2, however, only had an effect on PolB. We were able to disrupt the gene for PCNA2, whereas gene disruption for PCNA1 was not possible, suggesting that PCNA1 is essential for DNA replication. The sensitivities of the Δpcna2 mutant strain to ultraviolet irradiation (UV), methyl methanesulfonate (MMS) and mitomycin C (MMC) were indistinguishable from those of the wild‐type strain.  相似文献   
69.
We evaluated the effects of fragmin/protamine micro-particles (F/P MPs) containing FGF-2 (F/P MP-F) as carriers for the controlled release of FGF-2 for adipocyte-survival and capillary formation in inbred rats with subdivided free fat grafts. F/P MPs could immobilize FGF-2, thereafter gradually releasing the bound FGF-2. Inbred Fisher 344 rats weighing around 150 g were anesthetized and implanted with paste comprising harvested fat combined with F/P MP-F. The effect of F/P MP-F on the survival, granulation, and capillary formation in fat grafts was histologically compared with control grafts containing either FGF-2, F/P MPs or PBS. The control fat grafts became attached to tissues adjacent to the implantation site and were significantly resorbed after 30 days. In contrast, pink, soft, supple grafts were compressible and were little resorbed in the group given F/P FP MP-F at 30-120 days. Normal adipocytes were obviously decreased in the control groups with increased granulation tissues, whereas normal adipocytes with capillary formations were maintained in the F/P MP-F group. Thus, adding F/P MP-F to subdivided fat grafts helps to improve graft volume retention and survival in soft-tissue reconstruction through accelerating adipocyte-survival rates and angiogenesis.  相似文献   
70.
The clinical efficacy of hepatocyte growth factor (HGF) in tissue repair can be greatly enhanced by high affinity, biocompatible drug carriers that maintain the bioactivity and regulate release at the target site. We produced 0.5–3.0 μm fragmin (low molecular weight heparin)/protamine microparticles (F/P MPs) as carriers for the controlled release of HGF. F/P MPs immobilized more than 3 μg of HGF per mg of MPs and gradually released the absorbed HGF into the medium with a half-release time of approximately 5 days. Compared with HGF alone, HGF-containing F/P MPs substantially enhanced the mitogenic effect of HGF on cultured human microvascular endothelial cells, by prolonging the biological half-life, and its conjugation to F/P MPs protected HGF from heat and proteolytic inactivation. F/P MPs disappeared 8 days after subcutaneous injection in mice, suggesting that they are rapidly biodegraded. Furthermore, the number of large (diameter ?200 μm or containing ?100 erythrocytes) and medium (diameter 20–200 μm or containing 10–100 erythrocytes) lumen capillaries 8 days after injection of HGF-containing F/P MPs was significantly higher than that after injection of HGF or F/P MPs alone. Furthermore, the number of small (diameter ?20 μm or containing 1–10 erythrocytes) lumen capillaries was significantly higher 4 days after injection of HGF-containing F/P MPs. This increased angiogenic activity of HGF in vivo is probably due to both sustained local release and protection against biodegradation by the F/P MPs. Thus, F/P MPs may be useful and safe HGF carriers that facilitate cell proliferation and vascularization at sites of tissue damage.  相似文献   
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