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21.
22.
A multi-center, randomized controlled collaborative study was conducted in 310 institutions located throughout Japan for 3 years and 9 months from February 1985 until October 1988 to evaluate the efficacy of post-operative adjuvant therapy for patients who had previously undergone curative surgery for treatment of Stage IIIa breast cancer. Patients with estrogen receptor-positive [ER( + )] breast cancer were treated with two types of regimens, ie, cyclophosphamide + adriamycin + fluorouracil (CAF; 2 cycles) + Futraful (FT) or CAF (2 cycles) + FT + tamoxifen (TAM), and the clinical benefit of additional use of TAM was evaluated. Of the 509 ER( + ) patients registered for the trial, 473 patients (92.9%) were eligible for evaluation. The 5-year survival rate was 77.2% for the CAF + FT group and 74.6% for the CAF + FT+TAM group, and the 5-year disease-free survival rate was 56.7% for the CAF+FT group and 59.2% for the CAF + FT + TAM group. Neither the survival rate nor the disease-free survival rate differed significantly between the groups. Analyses by factor revealed that the 5-year disease-free rate for lymph node-negative patients in the CAF + FT + TAM group was significantly higher than that for the corresponding patients in the CAF + FT group. No differences were noted in the incidence of adverse reactions between the two treatment groups, other than an increase in LDH (the frequency of which was higher in the CAF + FT+TAM group than in the CAF + FT group). Patients with estrogen receptor-negative [ER( -)] breast cancer were treated with two types of regimens, ie, CAF + FT or CAF + FT + adriamycin (ADR), and the clinical benefit of the combined use of intermittent doses of ADR was evaluated. Of the 514 ER(-) patients registered in the trial, 478 (93.0%) were eligible for evaluation. The 5-year survival rate was 64.9% for the CAF + FT group and 63.0% for the CAF + FT + ADR group, and the 5-year disease-free survival rate was 59.2% for both CAF + FT and CAF + FT + ADR groups. Neither the survival rate nor the disease-free survival rate differed significantly between the groups. There were no significant differences between these groups in analyses by nodal or menopausal status. The incidences of adverse reactions including anorexia, nausea/vomiting and alopecia were higher in the CAF + FT+ADR group than in the CAF + FT group.  相似文献   
23.
BACKGROUND: Disorders of the DNA repair system that protects against alkylating mutagens are known to play an important role in carcinogenesis. METHODS: We investigated the expression of the DNA repair enzyme that protects against alkylating mutagens, O(6)-methylguanine DNA methyltransferase (MGMT), and the mismatch repair (MMR) enzymes, hMLH1 and hMSH2, in 135 gastric cancer specimens by immunohistochemical means. RESULTS: The immunoreactivity of MGMT and MMR proteins correlated significantly with several clinicopathologic factors. The survival curve in 116 patients showed that a loss of MGMT or hMLH1, but not of hMSH2, correlated with a poor prognosis. Combined evaluation of MGMT and hMLH1 revealed that the survival of patients with negative status for both MGMT and hMLH1 was shortest. However, this significant association between patient survival and MGMT or hMLH1 expression disappeared when early and advanced cancers were separately analyzed, indicating that synchronous losses of MGMT and hMLH1 increase during tumor progression and stage. Further evaluation according to histologic type revealed that loss of MGMT, hMLH1, and hMSH2 expression significantly differed between early and advanced cancer in differentiated-type cancers. In contrast, in undifferentiated-type cancer, loss of MGMT and MMR expression was frequently found even in intramucosal (m) cancer, and no significant difference was found in loss of hMLH1 and hMSH2 between early and advanced cancer. CONCLUSION: These findings demonstrate that the reduced expression of MGMT, hMLH1, and hMSH2 in differentiated-type cancer may play an important role during tumor progression between the early and advanced stage. On the other hand, in undifferentiated-type cancer, loss of MGMT and the MMR proteins appears to be an important event at carcinogenesis or at an earlier step of tumor progression.  相似文献   
24.

Background  

Neuromyelitis optica (NMO) is a recurring inflammatory neurological disease characterized by severe optic neuritis and myelitis. The purpose of this study was to determine whether the retinal nerve fiber layer thickness (RNFLT) is correlated with the clinical presentations in patients with NMO and to determine the clinical factors that lead to poor visual outcomes.  相似文献   
25.
Tranexamic acid (TXA) reduces the risk of bleeding trauma death without altering the need for blood transfusion. We examined the effects of TXA on coagulation and fibrinolysis dynamics and the volume of transfusion during the early stage of trauma. This subanalysis of a prospective multicenter study of severe trauma included 276 patients divided into propensity score–matched groups with and without TXA administration. The effects of TXA on coagulation and fibrinolysis markers immediately at (time point 0) and 3 hours after (time point 3) arrival at the emergency department were investigated. The transfusion volume was determined at 24 hours after admission. TXA was administered to the patients within 3 hours (median, 64 minutes) after injury. Significant reductions in fibrin/fibrinogen degradation products and D-dimer levels from time points 0 to 3 in the TXA group compared with the non-TXA group were confirmed, with no marked differences noted in the 24-hour transfusion volumes between the 2 groups. Continuously increased levels of soluble fibrin, a marker of thrombin generation, from time points 0 to 3 and high levels of plasminogen activator inhibitor-1, a marker of inhibition of fibrinolysis, at time point 3 were observed in both groups. TXA inhibited fibrin(ogen)olysis during the early stage of severe trauma, although this was not associated with a reduction in the transfusion volume. Other confounders affecting the dynamics of fibrinolysis and transfusion requirement need to be clarified.  相似文献   
26.
Protein kinase C delta (PKCδ) is a multifunctional PKC family member and has been implicated in many types of cancers, including liver cancer. Recently, we have reported that PKCδ is secreted from liver cancer cells, and involved in cell proliferation and tumor growth. However, it remains unclear whether the extracellular PKCδ directly regulates cell surface growth factor receptors. Here, we identify epidermal growth factor receptor (EGFR) as a novel interacting protein of the cell surface PKCδ in liver cancer cells. Imaging studies showed that secreted PKCδ interacted with EGFR‐expressing cells in both autocrine and paracrine manners. Biochemical analysis revealed that PKCδ bound to the extracellular domain of EGFR. We further found that a part of the amino acid sequence on the C‐terminal region of PKCδ was similar to the putative EGFR binding site of EGF. In this regard, the point mutant of PKCδ in the binding site lacked the ability to bind to the extracellular domain of EGFR. Upon an extracellular PKCδ‐EGFR association, ERK1/2 activation, downstream of EGFR signaling, was apparently induced in liver cancer cells. This study indicates that extracellular PKCδ behaves as a growth factor and provides a molecular basis for extracellular PKCδ‐targeting therapy for liver cancer.  相似文献   
27.
Olfactory bulbectomy (OBX) in mice elicits impaired memory and cognitive functions. Here, we found that chronic oral administration of spiro[imidazo[1,2-a]pyridine-3,2-indan]-2(3H)-one (ZSET1446/ST101) (0.1-1 mg/kg/day), a novel cognitive enhancer, significantly improved memory deficits as assessed by Y-maze and novel object recognition tasks in OBX mice. Immunostaining of cholinergic neurons in the medial septum by using an anti-choline acetyltransferase antibody indicated that chronic ZSET1446 treatment did not rescue cholinergic neurons. However, chronic treatment significantly restored OBX-induced decreases both in calcium/calmodulin-dependent protein kinase II (CaMKII) and protein kinase C (PKC) phosphorylation without improving decreased extracellular signal-regulated kinase phosphorylation in the hippocampal CA1 region. Consistent with enhanced CaMKII and PKC phosphorylation, ZSET1446 treatment improved glutamate receptor 1 (Ser-831) phosphorylation in the hippocampal CA1 region. ZSET1446 treatment also significantly rescued impaired long-term potentiation (LTP) in the hippocampal CA1 region of OBX mice. Taken together, the cognition-enhancing effect of ZSET1446 is probably mediated in part by stimulation of CaMKII and PKC activities, which in turn rescue impaired hippocampal LTP in OBX mice.  相似文献   
28.
Background: Acoustic radiation force impulse (ARFI) is a new technology integrated into conventional B‐mode ultrasonography. ARFI is used to evaluate tissue stiffness in several organs, but this method has not been applied for liver fibrosis. Aim: The aim of this study was to determine whether ARFI elastography is useful for the evaluation of liver fibrosis. Methods: This study enrolled 55 consecutive patients with chronic liver disease who underwent a liver biopsy for histological assessment of liver fibrosis by the Metavir scoring system. Liver stiffness of the 55 patients and 25 healthy volunteers was evaluated by ARFI elastography and was expressed as the shear wave velocity. Cut‐off values were determined using receiver‐operating characteristic (ROC) curves. Results: Histological liver fibrosis was evaluated by Metavir scoring; F0: six cases, F1: 14 cases, F2: nine cases, F3: nine cases and F4: 17 cases. Liver stiffness determined by ARFI elastography was correlated with histological liver fibrosis (P<0.0001). The areas under the ROC curves were 0.94 (95% confidence intervals, 0.87–0.99) for F2–F4, 0.94 (0.88–0.99) for F3–F4 and 0.96 (0.91–1.01) for F4. The cut‐off values of the shear wave velocity were as follows: >1.34 m/s for F2–F4 (sensitivity 91.4%, specificity 80%); >1.44 m/s for F3–F4 (sensitivity 96.2%, specificity 79.3%); and >1.80 m/s for F4 (sensitivity 94.1%, specificity 86.8%). Conclusions: Ultrasonic ARFI elastography is a novel, non‐invasive and reliable method for the assessment of liver fibrosis in patients with chronic liver disease.  相似文献   
29.
In this review article, we demonstrate the mucin expression profile in normal tissue, invasive ductal carcinoma (IDC), two subtypes of intraductal papillary–mucinous neoplasm (IPMN dark cell type and IPMN clear cell type), pancreatic intraepithelial neoplasia (PanIN), and mucinous cystic neoplasm (MCN) of the pancreas. In MUC1, there are various glycoforms, such as poorly glycosylated MUC1, sialylated MUC1, and fully glycosylated MUC1. IDCs showed high expression of all the glycoforms of MUC1. IPMNs dark cell type showed no expression or low expression of all the glycoforms of MUC1. IPMNs clear cell type showed low expression of poorly glycosylated MUC1, but expression of sialylated MUC1 and fully glycosylated MUC1. Expression of MUC2 was negative in IDCs, high in IPMNs dark cell type and low in IPMNs clear cell type. MUC5AC was highly expressed in IDCs, IPMNs dark cell type, and IPMNs clear cell type. MUC6 expression was higher in IPMNs clear cell type than in IDCs and IPMNs dark cell type. Our recent study demonstrated that high expression of MUC4 in IDCs is correlated with a poor outcome for patients. In PanINs, expression of both MUC5AC and MUC6 are an early event, whereas up-regulation of MUC1 is a late event. MCNs do not look as if they will show a specific mucin expression profile according to the literature review.  相似文献   
30.
The 4-aminopyridine (4AP) sensitive outward current of enzymatically dispersed single smooth muscle cells of the rabbit main pulmonary artery were investigated using the voltage clamp method. When the cell was exposed to physiological salt solution (PSS) in the bath and high K+ in the pipette no inward current was generated by depolarization of the membrane, but when 4AP was present in the bath or when Cs+ with tetraethylammonium+ (Cs+-TEA+) in the pipette, an inward current was generated. This current was enhanced by Ba2+ or high Ca2+ and was blocked by inorganic or organic Ca2+ channel blockers.The outward current was partly inhibited by the Ca2+ channel blockers, Ca2+-free or Mn2+ containing solution. The residual outward current was blocked by external application of 10 mM 4AP, whereas it was inhibited by half with 100 mM TEA+. To investigate further natures of 4AP sensitive outward current, the following experiments were done in the bath solution containing 2.5 mM Mn2+. The reversal potential of this outward current, estimated from the tail current, remained the same in Na+-deficient solution, but shifted to near the K+-equilibrium potential in Cl deficient solution. Thus, the main current carrier for the outward current seems to be K+, but Cl may participate to some extent. The amplitude of the outward current decreased slowly. However, the reversal potential was not changed, suggesting the reduction in amplitude of the outward current was not due to the accumulation of K+ on the outer surface of the membrane. As 4AP inhibited the outward current to a greater extent at lower than higher membrane potential levels, 4AP bound to the channel may be dislodged at higher levels. When pH of the bath solution was modified from 7.3 to 8.0, inhibitory actions of 4AP were enhanced (pKa value of 4AP=9.17). Thus, a non-ionized form of 4AP may act as a channel blocker. We conclude that in smooth muscle cells of the pulmonary artery, lack of an action potential in physiological solution may partly be due to a small inward current as well as a large contribution of the 4AP sensitive outward current.  相似文献   
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