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61.
Tuberculosis (TB) is a disease caused by the pathogen Mycobacterium tuberculosis. Prolonged administration of high dose antibiotics using oral and injectable routes and their associated side effects show limitations to successful treatment outcome of TB. Nanocarrier-based dry powder inhalers (DPIs) may provide a breakthrough as an alternative therapeutic approach because of their stable, non-invasive nature and ability to target the drug at the site of infection. The current review focuses on the roadmap of the respiratory system, drug deposition and targeting at the site of infection via the pulmonary route. This review will provide readers with an overview of the existing literature of nanocarrier-based DPIs of anti-TB drugs. Among different nanocarriers, results of most of the proliposomes and polymeric particles-based DPIs with respect to their characterisation parameters like encapsulation efficiency, drug loading, storage stability and aerodynamic properties are not encouraging, whereas surface engineered, nanostructured lipid carriers (NLCs), i.e. ligand attached-NLCs-based dry powder inhalers (NLCs-DPI) show promising results. But still, there is a need to investigate them for in vitro, ex vivo, in vivo and toxicity studies to achieve a market approval.  相似文献   
62.
BackgroundCrizotinib produces high response rates and prolonged PFS in ALK+ NSCLC. Retrospective analyses suggest enhanced sensitivity to pemetrexed in crizotinib naive ALK+ NSCLC. Cross-resistance between crizotinib and pemetrexed has not been previously investigated.Patients and MethodsPatients with stage IV ALK+ NSCLC treated with PEM-CRIZ, or CRIZ-PEM were identified. Overall PFS and PFS excluding central nervous system events (eCNS) were compared.ResultsObjective response rates in evaluable patients were 66% (PEM-CRIZ) and 75% (CRIZ-PEM) for pemetrexed and 84% (CRIZ-PEM) and 66% (PEM-CRIZ) for crizotinib. For PEM-CRIZ (n = 29), median PFS and eCNS PFS were both 6 months with pemetrexed, and 10 and 14.5 months, respectively, with crizotinib. For CRIZ-PEM (n = 9), median PFS and eCNS PFS were 4.5 and 3 months, respectively, with pemetrexed, and 8.5 and 7.5 months, respectively, with crizotinib. There was a statistically significant increase in the risk of an overall PFS event with pemetrexed when administered after crizotinib (P = .0277; hazard ratio [HR], 2.5898; 95% confidence interval [CI], 1.1100-6.0424), but differences in the risk of an eCNS PFS event were not significant (P = 0.4913; HR, 1.3521; 95% CI, 0.5727-3.1920). Neither overall nor eCNS PFS for patients while taking crizotinib was associated with a sequence effect relative to pemetrexed.ConclusionCrizotinib and pemetrexed are active drugs in ALK+ NSCLC. PFS benefit appeared higher with crizotinib than with pemetrexed. PFS benefit from pemetrexed was less after crizotinib compared with before crizotinib, however, this difference was only statistically significant for overall and not eCNS PFS. Pemetrexed exposure did not seem to affect crizotinib outcomes.  相似文献   
63.
Rational drug design based on molecular targets is starting to revolutionize cancer care. To maximize its potential for patients, a concomitant leveraging of molecular knowledge for selection of patients to future and current therapeutic options is paramount. The terms “individualized”, “personalized”, or “precision therapy” are currently used to describe these efforts. Here, we summarize current knowledge for selection of systemic targeted and cytotoxic therapy for patients with non-small-cell lung cancer. Based on this knowledge, we present a potential decision algorithm to best select patients for currently available therapies, which include the treatment options single-agent erlotinib or gefitinib, the ALK inhibitor crizotinib, double agent gemcitabine and platinum, double agent platinum and pemetrexed, and as a default option a taxane combined with a non-platinum drug, for instance a vinca alkaloid. The addition of bevacizumab to double-agent chemotherapy is also discussed. Currently available data on predictive biomarkers are largely based on subgroup or companion biomarker analyses of patient cohorts or clinical trials. Current and emerging markers must be incorporated prospectively into the design of clinical trials that test novel and established agents to better understand their clinical utility and to refine selection parameters and marker interactions. Future development will lead to increasing complexity in clinical decision making with substantial anticipated benefits to patients including increased therapeutic efficacy, reduced toxicity, and better quality of life.  相似文献   
64.

BACKGROUND:

Epidermal growth factor receptor tyrosine kinase inhibitors (EGFR‐TKIs) have shown modest clinical benefit in patients with relapsed nonsmall cell lung cancer (NSCLC). Down‐regulation of Akt appears to correlate with the antitumor activity of EGFR‐TKIs. Akt activates nuclear factor kappa B (NF‐κB), which transcribes genes important for cell survival, invasion, and metastasis. The authors hypothesized that genistein, through the inhibition of NF‐κB, could enhance the activity of EGFR‐TKIs in NSCLCs.

METHODS:

Three NSCLC cell lines with various EGFR mutation status and sensitivities to EGFR‐TKIs were selected: H3255 (L858R), H1650 (del E746‐A750), and H1781 (wild‐type EGFR). Cells were treated with erlotinib, gefitinib, genistein, or the combination of each of the EGFR‐TKIs with genistein. Cell survival and apoptosis were assessed, and expression levels of EGFR, pAkt, cyclooxygenase‐2 (COX‐2), E‐cadherin, prostaglandin E2 (PGE2), and NF‐κB were measured.

RESULTS:

Both EGFR‐TKIs demonstrated growth inhibition and apoptosis in each of the cell lines, but H1650 and H1781 were much less sensitive. Genistein demonstrated some antitumor activity in all cell lines, but enhanced growth inhibition and apoptosis when combined with the EGFR‐TKIs in each of the cell lines. Both combinations down‐regulated NF‐κB significantly more than either agent alone in H3255. In addition, the combinations reduced the expression of EGFR, pAkt, COX‐2, and PGE2, consistent with inactivation of NF‐κB.

CONCLUSIONS:

The authors concluded that genistein enhances the antitumor effects of EGFR‐TKIs in 3 separate NSCLC cell lines. This enhanced activity is in part because of greater reduction in the DNA‐binding activity of NF‐κB when EGFR‐TKIs were combined with genistein. Cancer 2009. © 2009 American Cancer Society.  相似文献   
65.
PURPOSE: Neurotuberculosis is a relatively common form of tuberculosis and may be seen in 1-10% of patients of systemic tuberculosis and may present in several forms. Ocular lesions are frequently seen, most commonly optic nerve lesions. Limited data are available for choroidal tubercles. We conducted a prospective study 1) to determine the prevalence of choroidal tubercles in a cohort of patients of neurotuberculosis as well as its relative prevalence in the various morphological manifestations and 2) to study the role of co-existent systemic tuberculous infection. METHODS: IRB-approved prospective cross-sectional observational study. A hospital-based cohort of patients underwent a detailed physical, laboratory and ocular evaluation. RESULTS: A total of 52 (20 male, 32 female) patients were evaluated with tubercles being seen in 23 eyes (18 patients, 34.6%).Twenty four patients (46.12%, 16 female, 8 male) presented with intracranial granulomas and 28 (53.8%, 16 female, 12 male) presented with tuberculous meningitis. Tubercles were seen in 10 eyes of 8 (28.5%) patients with tuberculous meningitis and in 13 eyes of 10 patients (41.6%) with intracranial granulomas. This result is not statistically significant.Twenty seven patients (51.9%) had neurotuberculosis without systemic infection, whereas 25 (48.1%) patients had systemic foci. Tubercles were seen in 18 eyes (13 patients) with systemic foci and in 5 eyes (5 patients) of neurotuberculosis alone. The odds ratio for the presence of systemic tuberculosis when choroidal tubercles are present is 5.6 (95% confidence interval: 1.39-24.49, statistically significant [p = 0.005]). CONCLUSIONS: Tubercles were equally likely to occur in either manifestation of neurotuberculosis, and their presence was related to the presence of systemic focus of tuberculous infection. The presence of choroidal tubercles may serve as a diagnostic marker for the presence of an underlying systemic infection.  相似文献   
66.
PURPOSE: To report the clinical experience with an electromagnetic treatment target positioning and continuous monitoring system in patients with localized prostate cancer receiving external beam radiotherapy. METHODS AND MATERIALS: The Calypso System is a target positioning device that continuously monitors the location of three implanted electromagnetic transponders at a rate of 10 Hz. The system was used at five centers to position 41 patients over a full course of therapy. Electromagnetic positioning was compared to setup using skin marks and to stereoscopic X-ray localization of the transponders. Continuous monitoring was performed in 35 patients. RESULTS: The difference between skin mark vs. the Calypso System alignment was found to be >5 mm in vector length in more than 75% of fractions. Comparisons between the Calypso System and X-ray localization showed good agreement. Qualitatively, the continuous motion was unpredictable and varied from persistent drift to transient rapid movements. Displacements > or =3 and > or =5 mm for cumulative durations of at least 30 s were observed during 41% and 15% of sessions. In individual patients, the number of fractions with displacements > or =3 mm ranged from 3% to 87%; whereas the number of fractions with displacements > or =5 mm ranged from 0% to 56%. CONCLUSION: The Calypso System is a clinically efficient and objective localization method for positioning prostate patients undergoing radiotherapy. Initial treatment setup can be performed rapidly, accurately, and objectively before radiation delivery. The extent and frequency of prostate motion during radiotherapy delivery can be easily monitored and used for motion management.  相似文献   
67.

Introduction

First-line epidermal growth factor receptor (EGFR) tyrosine kinase inhibitor treatment of advanced non–small-cell lung cancer with EGFR-activating mutations improves outcomes compared with chemotherapy, but resistance develops in most patients. Compensatory signaling through type 1 insulin-like growth factor 1 receptor (IGF-1R) may contribute to resistance; dual blockade of IGF-1R and EGFR may improve outcomes.

Patients and Methods

We performed a randomized, double-blind, placebo-controlled phase II study of linsitinib, a dual IGF-1R and insulin receptor tyrosine kinase inhibitor, plus erlotinib versus placebo plus erlotinib in chemotherapy-naive patients with EGFR-mutation positive, advanced non–small-cell lung cancer. Patients received linsitinib 150 mg twice daily or placebo plus erlotinib 150 mg once daily on continuous 21-day cycles. The primary end point was progression-free survival.

Results

After randomization of 88 patients (44 each arm), the trial was unblinded early owing to inferiority in the linsitinib arm. The median progression-free survival for the linsitinib versus the placebo group was 8.4 months versus 12.4 months (hazard ratio, 1.37; P = .29). Overall response rate (47.7% vs. 75.0%; P = .02) and disease control rate (77.3% vs. 95.5%; P = .03) were also inferior. Whereas most adverse events were ≤ grade 2, linsitinib plus erlotinib was associated with increased adverse events that led to decreased erlotinib exposure (median days, 228 vs. 305). No drug-drug interaction was suggested by pharmacokinetic and pharmacodynamic results.

Conclusion

Adding linsitinib to erlotinib resulted in inferior outcomes compared with erlotinib alone. Further understanding of the signaling pathways and a biomarker that can predict efficacy is needed prior to further clinical development of IGF-1R inhibitors in lung cancer.  相似文献   
68.
Background Cediranib is a highly potent vascular endothelial growth factor (VEGF) signaling inhibitor of all three VEGF receptors. This phase I, single-center, dose-finding study was designed primarily to investigate the safety and pharmacokinetics (PK) of cediranib with various anticancer regimens in patients with advanced solid tumors. Experimental design Oral cediranib 20, 30, and/or 45 mg/day was given in combination with standard mFOLFOX6; docetaxel; irinotecan; irinotecan and cetuximab; or pemetrexed. The novel study design allowed simultaneous evaluation of the safety and PK of these regimens with cediranib in one study. Secondary assessments included a preliminary evaluation of efficacy. Results Fifty-nine patients received cediranib and were evaluable for safety. The most common adverse events across the study were fatigue and diarrhea (both n = 52). The most common CTC grade ≥ 3 adverse events were neutropenia (n = 19) and fatigue (n = 16). Cediranib did not appear to have a major effect on the PK profile of any chemotherapy agent tested. A preliminary assessment of efficacy showed that objective responses were achieved in some patients (n = 6) who had previously progressed on similar regimens without cediranib. Conclusion In this group of heavily pretreated patients, the study design permitted simultaneous assessment of multiple treatment arms. Treatment with cediranib and the various anticancer regimens was generally well tolerated, with no apparent PK interaction and preliminary evidence of antitumor activity.  相似文献   
69.
IntroductionAt the prior data cutoff (February 9, 2017) the ALEX trial showed superior investigator-assessed progression-free survival (PFS) for alectinib versus crizotinib in untreated, anaplastic lymphoma kinase (ALK)-positive, advanced NSCLC (hazard ratio = 0.47, 95% confidence interval: 0.34–0.65, p < 0.001). The median PFS in the alectinib arm was not reached versus 11.1 months with crizotinib. Retrospective analyses suggest that the echinoderm microtubule-associated protein-like 4 gene-ALK variant (EML4-ALK) may influence ALK-inhibitor treatment benefit. We present updated analyses, including exploratory subgroup analysis by EML4-ALK variant, after an additional 10 months’ follow-up (cutoff December 1, 2017).MethodsPatients were randomized to receive twice-daily alectinib, 600 mg, or crizotinib, 250 mg, until disease progression, toxicity, death, or withdrawal. PFS was determined by the investigators. Baseline plasma and tissue biomarker samples were analyzed by using hybrid-capture, next-generation sequencing to determine EML4-ALK variant.ResultsBaseline characteristics were balanced. Investigator-assessed PFS was prolonged with alectinib (stratified hazard ratio = 0.43, 95% confidence interval: 0.32–0.58). The median PFS times were 34.8 months with alectinib and 10.9 months with crizotinib. EML4-ALK fusions were detectable in 129 patient plasma samples and 124 tissue samples; variants 1, 2, and 3/ab did not affect PFS, objective response rate, or duration of response. Investigator-assessed PFS was longer for alectinib than for crizotinib across EML4-ALK variants 1, 2, and 3a/b in plasma and tissue. Despite longer treatment duration (27.0 months in the case of alectinib versus 10.8 months in the case of crizotinib), the safety of alectinib compared favorably with that of crizotinib.ConclusionAlectinib continues to demonstrate superior investigator-assessed PFS versus crizotinib in untreated ALK-positive NSCLC, irrespective of EML4-ALK variant.  相似文献   
70.

Introduction

Anti-EGFR agents are standard treatments for patients with EGFR-mutant advanced NSCLC. The feasibility of combining erlotinib or gefitinib with the anti–programmed death 1 immunotherapy pembrolizumab was evaluated in the phase 1/2 KEYNOTE-021 study (NCT02039674).

Methods

Adults with previously untreated stage IIIB/IV EGFR-mutant NSCLC were treated with pembrolizumab 2 mg/kg intravenously every 3 weeks plus oral erlotinib 150 mg daily in cohort E or oral gefitinib 250 mg daily in cohort F, using a 3 + 3 design with cohort expansion. rTumor response was evaluated per Response Evaluation Criteria in Solid Tumors version 1.1 by blinded independent central review. The primary objective was determination of a recommended phase 2 dose.

Results

Twelve patients enrolled to receive pembrolizumab plus erlotinib and seven to receive pembrolizumab plus gefitinib. No dose-limiting toxicities or grade 5 events occurred. Pembrolizumab plus erlotinib was feasible, with adverse events similar to those expected for monotherapy. However, pembrolizumab plus gefitinib was not feasible due to grade 3/4 liver toxicity in five of seven patients (71.4%), leading to permanent treatment discontinuation in four patients. The most frequently occurring treatment-related adverse events with pembrolizumab plus erlotinib were rash (50.0%), dermatitis acneiform, diarrhea, hypothyroidism, and pruritus (33.3% each). The objective response rate was 41.7%, including response in all four patients with programmed death ligand 1 expression 50% or greater.

Conclusions

Although pembrolizumab plus gefitinib was not feasible, the toxicity profile observed with pembrolizumab plus erlotinib suggests combining immunotherapy with anti-EGFR therapy is feasible. Pembrolizumab plus erlotinib did not improve objective response rate compared with previous monotherapy studies; further evaluation would be necessary to evaluate potential effects on other efficacy outcomes.  相似文献   
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