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981.
Ubiquitin immunoreactive (UBQ-ir) inclusions were present to variable extents in the inferior olivary nucleus (ION) in 37/48 (77%) patients with frontotemporal lobar degeneration (FTLD), in 10/11 (91%) patients with motor neurone disease (MND), in 5/5 (100%) patients with Alzheimer’s disease (AD), 5/7 (71%) patients with dementia with Lewy bodies, 13/19 (68%) patients with Parkinson’s disease, 11/11(100%) patients with Progressive Supranuclear Palsy, 2/6 (33%) patients with Multisystem Atrophy, 1/3 (33%) patients with Huntington’s disease and in 14/14 (100%) normal elderly control subjects. In FTLD, UBQ-ir inclusions were present in 26/32 (81%) patients with FTLD-U, in 10/15 (67%) patients with tauopathy, and in the single patient with Dementia Lacking Distinctive Histology. In 13 FTLD-U patients, and in a single AD and in 2 MND patients, the UBQ-ir inclusions had a rounded, spicular or skein-type appearance, and these were also TDP-43 immunoreactive (TDP-43-ir). In all other affected patients in all diagnostic groups, and in control subjects, the UBQ-ir neuronal cytoplasmic inclusions (NCI) were of a conglomerated type, resembling a cluster of large granules or globules, but were never TDP-43-ir. In 3 of the 13 FTLD-U patients with spicular NCI, conglomerated NCI were also present but in separate cells. Double-labelling immunohistochemistry, and confocal microscopy, for UBQ and TDP-43 confirmed that only the spicular UBQ-ir inclusions in patients with FTLD-U, AD and MND contained TDP-43, though in these patients there were occasional TDP-43 immunoreactive inclusions that were not UBQ-ir. Nuclear TDP-43 immunoreactivity was absent in ION in FTLD-U, AD or MND when TDP-43 cytoplasmic inclusions were present, but remained in neurones with UBQ-ir, TDP-43 negative inclusions. The target protein within the UBQ-ir, TDP-43-negative inclusions remains unknown, but present studies indicate that this is not tau, neurofilament or internexin proteins. These TDP-43 negative, UBQ-ir inclusions appear to be more related to ageing than neurodegeneration, and are without apparent diagnostic significance. The pathophysiological mechanism leading to their formation, and any consequences their presence may have on nerve cell function, remain unknown.  相似文献   
982.
We evaluated the efficacy of daunorubicin (40 mg/m(2)/day for 5 days, 200 mg/m(2)/cycle) combined with standard dose of cytarabine (100 mg/m(2)/day for 7 days) for acute myelogenous leukemia patients aged 65-74 years as induction therapy. Complete remission (81.3%) was achieved in 13 of 16 patients following the therapeutic program. The median duration of recovering absolute neutolophilic counts over 1000/μl and platelet counts over 100 000/μl were 33 days and 27 days, respectively. None of the patients had any adverse cardiac complications or died during administration of the induction therapy. Patients achieving complete remission received post-remission therapy consisting of two regimens other than induction therapy. The 3-year disease-free and overall survival rates were 36.9 and 50.0%, respectively. Extending the total period of the daunorubicin therapy might be an alternative to increasing the daily dose of daunorubicin in the induction therapy for elderly patients who were candidates for receiving intensified chemotherapy.  相似文献   
983.
The anti-tumor effect of a cyclooxygenase (COX)-2 selective inhibitor or a non-specific immunostimulant (PSK) alone, as well as the anti-tumor effect of their combined administration were examined on a hepatic metastasis model of colon cancer using a colon 26 cell line (CT26) and its highly metastatic variant. Anti-tumor effects were assessed by the number of hepatic metastases. Serum MMP-9, TGF-β and IL-6 were also measured. In a preliminary experiment, cells (5×10(5)) of a mouse colon cancer 26 cell line (CT26) and its highly metastatic variant were implanted below the splenic capsule in BALB/c and CDF1 mice. The number of hepatic metastatic CT26 cell lesions in the CDF1 mice of the non-spleen-removed group at 2 weeks was found to be optimum for the experiments. Although no significant difference was found, etodolac treatment showed the highest inhibitory effect on the number of hepatic metastases at a concentration of 30 mg/kg. In contrast, intraperitoneal administration of 50 mg/kg PSK showed an inhibitory effect on hepatic metastases, but a significant difference was not observed. PSK (p=0.002) or the combined use of etodolac and PSK (p=0.001) exhibited a significant inhibition of the number of hepatic metastases. In addition, MMP-9 was significantly inhibited by the single use of etodolac or PSK, and was inhibited with an additive effect by the combined use of etodolac and PSK. IL-6 and TGF-β were significantly inhibited following the combined use of etodolac and PSK. In conclusion, etodolac did not exhibit any significant hepatic metastasis inhibitory effect, whereas it significantly reduced the MMP-9 level. PSK reduced both the number of hepatic metastases and MMP-9. Combined use of etodolac and PSK did not show any additive effect in the inhibition of the number of hepatic metastases, whereas it inhibited MMP-9, TGF-β and IL-6, suggesting the benefit of a combined effect.  相似文献   
984.
The aim of the present study was to investigate the genetic factors responsible for the interindividual variability in the bioavailability of mizoribine. Thirty healthy Japanese men aged 20-49 years and weighing 53-75 kg participated in the present study and took 150 mg of mizoribine. Urine samples were collected periodically for 12 h after the dose, and the bioavailability of mizoribine was calculated from the estimated total urinary excretion from time zero to infinity. The bioavailability of mizoribine in the 30 subjects ranged from 60.3% to 99.4%. The mean bioavailability of mizoribine in subjects with the concentrative nucleoside transporter 1 (SLC28A1) 565-A/A allele (75.4%) was significantly lower than that in subjects with the SLC28A1 565-G/G allele (90.1%). On the other hand, the bioavailability of mizoribine was not affected by polymorphisms of breast cancer resistance protein (ABCG2) C421A and multidrug resistance-associated protein 4 (ABCC4) G2269A. The findings in the present prospective study suggested that the genetic test for the SLC28A1 G565A polymorphism is promising for predicting the Japanese subjects with lower bioavailability of mizoribine.  相似文献   
985.
986.
In order to investigate better molecular-target therapy for acute myeloid leukemia (AML), we conducted a phase I trial of a combination of gemtuzumab ozogamicin (GO) with conventional chemotherapy. Between January 2007 and December 2009, a total of 19 adult Japanese patients with relapsed or refractory CD33-positive AML (excluding acute promyelocytic leukemia) were enrolled. All registered patients received a standard dose of cytarabine (Ara-C) (100 mg/m(2) × 7 days), combined with either idarubicin (IDR) (10-12 mg/m(2) × 3 days) or daunorubicin (DNR) (50 mg/m(2) × 3-5 days), and then GO (3-5 mg/m(2) ), which was administered 1 day after the last infusion of IDR (IAG regimen) or DNR (DAG regimen). While doses of both GO and IDR and the administration period of only DNR were increased, the dose-limiting toxicity (DLT) was assessed. Among 19 patients (nine in the IAG regimen, 10 in the DAG regimen), the median age was 59 years (range 33-64), and the relapsed/refractory ratio was 13/6. In the therapy using 3 mg/m(2) GO in the IAG or DAG regimen, grade 3/4 leukopenia and neutropenia were observed in all patients, but none had grade 3/4 non-hematological toxicities, except febrile neutropenia. Three patients in the IAG regimen who were administered 5 mg/m(2) GO showed DLT. No patients had veno-occlusive disease or sinusoidal obstructive syndrome. In conclusion, 3 mg/m(2) GO combined with Ara-C and IDR or DNR can be safely administered, and phase II trials should be conducted to investigate the clinical efficacy of the combination therapy.  相似文献   
987.
Aquaporins (AQP) play important roles in water and glycerol transport. We examined whether AQP3 is expressed in primary squamous cell carcinoma (SCC) such as esophageal and oral cancer and lymph node metastasis, and whether AQP3 is a potential target for tumor therapy. A high level expression of AQP3 was observed in tumor areas of human primary SCC such as esophageal and lingual cancers, and lymph node metastasis, but was not observed in normal areas. Treatment with pan-AQP inhibitor caused apoptotic cell death on the SCC cell lines in a concentration-dependent manner. Small interfering RNA (siRNA) specific for AQP3 also inhibited cell adhesion and growth of SCC, but not those of adenocarcinoma cell lines and fibroblasts. Expression of integrin α5 and β1, counter adhesion molecules for fibronectin, was inhibited by treatment with AQP3-siRNA. The phosphorylation of focal adhesion kinase (FAK) was decreased by treatment with AQP3-siRNA, which then caused decreases in phosphorylation of Erk and MAPK. These results indicate that the decreases in integrins and the inhibition of cell adhesion might cause inhibition of the FAK signaling pathways. Combination of AQP3-siRNA with cisplatin, a major anti-cancer drug, strongly inhibited the growth of SCC. Cell death caused by the inhibition of AQP3 was a result of direct interference with cell adhesion involving intracellular FAK-MAPK signaling pathways. These results imply a potentially important and novel role for the inhibition of AQP3 function via the use of specific siRNA in the treatment of SCC.  相似文献   
988.

Objective

To achieve effective delivery of siRNA into target cells in vivo, we have developed a novel approach of siRNA delivery by using local drug delivery systems.

Results

The chitosan hydrogel (CH-HG) displayed a liquid-solid phase transition in a temperature-dependent manner and formed an endothermic hydrogel in tumor tissue after intra-tumoral injection. Additionally, we tested the extent of in vivo delivery following a single intra-tumoral injection of Alexa555 siRNA/CH-HG into A375SM-bearing mice. The Alexa555 siRNA demonstrated higher localization into tumor cells compared to control. The Alexa555 siRNA delivery extends to tumor cells outside of CH-HG and some tumor cells also infiltrated into CH-HG. For therapeutic proof-of-concept studies, CH-HG including TG2-targeted siRNA significantly inhibited tumor growth in melanoma (A375SM) and breast (MDA-MB231) tumor models compared to control (A375SM: 72% reduction and MDA-MB231: 92% reduction, p < 0.001).

Experimental Design

We prepared a CH-HG system loaded with siRNA to enhance localized therapeutic efficacy without risk for systemic side effects. Delivery of siRNA into CH-HG was confirmed by fluorescence microscopy. Antitumor efficacy was examined in mouse models of melanoma (A375SM) and breast (MDA-MD231) cancer.

Conclusions

This study developed a novel local delivery method for siRNA therapy using the CH-HG system. This approach could have broad applications for multiple localized diseases.Key words: RNA interference, chitosan, hydrogel, local delivery  相似文献   
989.
Lymph nodes from patients with colorectal cancer were immunohistochemically stained for cytokeratin to investigate the relationship between the presence of occult neoplastic cells (ONCs) and recurrence/metastasis. A total of 80 patients with stage III/Dukes' C colorectal cancer were divided into 16 patients who developed recurrence/metastasis (recurrence group) and 64 patients without recurrence (non-recurrence group). ONCs were compared between the two groups with respect to i) single cells (≥ 3 floating ONCs), ii) clusters of cells (1 or more floating aggregates of 2-20 ONCs) and iii) single cells + clusters. When single cells were detected, the sensitivity for recurrence was 87.5% (14/16, p = 0.002), the positive predictive value (PPV) was 32.6% (14/43), the specificity was 54.7% (35/64) and the negative predictive value (NPV) was 94.6% (35/37). For clusters, the sensitivity was 87.5% (14/16, p<0.001), PPV was 41.2% (14/34), specificity was 68.8% (44/64) and NPV 95.7% (44/46). With single cells + clusters, the values were 87.5% (14/16, p<0.001), 48.3% (14/29), 76.6% (49/64) and 96.1% (49/51), respectively. These results suggest that the detection of single cells + clusters is a sensitive indicator of a high risk of recurrence/ metastasis, while ONCs are useful for identifying the low-risk group of patients with stage III colorectal cancer.  相似文献   
990.

Background  

It has been suggested that thrombospondin-1 (TSP-1) plays a role in angiogenesis in many cancers. In addition, TSP-1 has been shown to suppress tumor growth by activating transforming growth factor-β (TGF-β). Recent studies have shown that Ski protein suppresses TGF-β signaling. The aim of this study was to investigate the role of TSP-1 and Ski expression in advanced gastric cancer.  相似文献   
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