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21.
Early identification of CKD risk factors may allow risk factor modification and prevention of CKD progression. We investigated the hypothesis that risk factors are present ≥30 years before the diagnosis of CKD in a case-control study using data from the Framingham Offspring Study. Patients with incident CKD (eGFR≤60 ml/min per 1.73 m2) at examination cycles 6, 7, and 8 were age- and sex-matched 1:2 to patients without CKD at baseline (examination 5). CKD risk factors were measured at each examination cycle. Logistic regression models, adjusted for age, sex, and time period, were constructed to compare risk factor profiles at each time point between cases and controls. During follow-up, 441 new cases of CKD were identified and matched to 882 controls (mean age 69.2 years, 52.4% women). Those who ultimately developed CKD were more likely to have hypertension (odds ratio [OR], 1.76; 95% confidence interval [CI], 1.23 to 2.51), obesity (OR, 1.71; 95% CI, 1.14 to 2.59), and higher triglyceride levels (OR, 1.43; 95% CI, 1.12 to 1.83) 30 years before CKD diagnosis, and were more likely to have hypertension (OR, 1.38; 95% CI, 1.07 to 1.79), higher triglyceride levels (OR, 1.35; 95% CI, 1.11 to 1.64), lower HDLc (OR, 0.89; 95% CI, 0.81 to 0.97), and diabetes (OR, 2.90; 95% CI, 1.59 to 5.29) 20 years before CKD diagnosis. These findings demonstrate that risk factors for CKD are identifiable ≥30 years before diagnosis and suggest the importance of early risk factor identification in patients at risk for CKD.  相似文献   
22.
Summary Serum concentrations of acute-phase-proteins C-reactive protein (CRP), 1-antitrypsin (AAT), 1-acid glycoprotein (AGP) as well as levels of immunoglobulins G, A and M and of complement components C3 and C4 were evaluated in 15 patients with advanced (stages III and IV) Hodgkin's disease. Of these patients 9 suffered from B symptoms including pruritus, night sweats and fever. While all patients had highly increased concentrations of CRP and AAT and 11 patients also had elevated levels of AGP in their sera, these concentrations were significantly (P<0.001) reducible by the administration of chemotherapy. Patients with B symptoms also had significantly higher concentrations of CRP (P<0.02), AAT (P<0.05) and AGP (P<0.05) in their sera than patients without. Plasmapheresis which was performed in 3 patients did not achieve a long-lasting reduction of serum concentrations of any acute-phase-protein tested. Complement components C3 and C4 exhibited a similar behaviour as acute-phase-proteins in that they were elevated in patients with B symptoms and reducible by the administration of chemotherapy (P<0.001 and P<0.02, respectively). We conclude that serum concentrations of CRP, AAT and AGP can serve as useful markers for the assessment of tumour activity in patients with advanced Hodgkin's disease. Whereas the concentrations of immunoglobulins G and A in patients were comparable to normal controls, IgM was significantly (P<0.05) reduced in patients who had received chemotherapy, but not in those who were newly diagnosed and hat not received any treatment. Thus, chemotherapy lowered serum concentrations of IgM without influencing levels of IgG and IgA.Supported in part by the Anton Dreher Memorial Donation for Medical Research  相似文献   
23.
Eye and head movements are coordinated during head-free pursuit. To examine whether pursuit neurons in frontal eye fields (FEF) carry gaze-pursuit commands that drive both eye-pursuit and head-pursuit, monkeys whose heads were free to rotate about a vertical axis were trained to pursue a juice feeder with their head and a target with their eyes. Initially the feeder and target moved synchronously with the same visual angle. FEF neurons responding to this gaze-pursuit were tested for eye-pursuit of target motion while the feeder was stationary and for head-pursuit while the target was stationary. The majority of pursuit neurons exhibited modulation during head-pursuit, but their preferred directions during eye-pursuit and head-pursuit were different. Although peak modulation occurred during head movements, the onset of discharge usually was not aligned with the head movement onset. The minority of neurons whose discharge onset was so aligned discharged after the head movement onset. These results do not support the idea that the head-pursuit-related modulation reflects head-pursuit commands. Furthermore, modulation similar to that during head-pursuit was obtained by passive head rotation on stationary trunk. Our results suggest that FEF pursuit neurons issue gaze or eye movement commands during gaze-pursuit and that the head-pursuit-related modulation primarily reflects reafferent signals resulting from head movements.  相似文献   
24.
BACKGROUND: Primary hyperoxaluria is a rare genetic disorder of glyoxylate metabolism that results in overproduction of oxalate. The disease is characterized by severe calcium oxalate nephrolithiasis and nephrocalcinosis, resulting in end-stage renal disease (ESRD) early in life. Most patients eventually require dialysis and kidney transplantation, usually in combination with the replacement of the liver. Reduction of urinary oxalate levels can efficiently decrease calcium oxalate depositions; yet, no treatment is available that targets oxalate biosynthesis. In previous in vitro studies, we demonstrated that pyridoxamine can trap reactive carbonyl compounds, including intermediates of oxalate biosynthesis. METHODS: The effect of PM on urinary oxalate excretion and kidney crystal formation was determined using the ethylene glycol rat model of hyperoxaluria. Animals were given 0.75% to 0.8% ethylene glycol in drinking water to establish and maintain hyperoxaluria. After 2 weeks, pyridoxamine treatment (180 mg/day/kg body weight) started and continued for an additional 2 weeks. Urinary creatinine, glycolate, oxalate, and calcium were measured along with the microscopic analysis of kidney tissues for the presence of calcium oxalate crystals. RESULTS: Pyridoxamine treatment resulted in significantly lower (by approximately 50%) levels of urinary glycolate and oxalate excretion compared to untreated hyperoxaluric animals. This was accompanied by a significant reduction in calcium oxalate crystal formation in papillary and medullary areas of the kidney. CONCLUSION: These results, coupled with favorable toxicity profiles of pyridoxamine in humans, show promise for therapeutic use of pyridoxamine in primary hyperoxaluria and other kidney stone diseases.  相似文献   
25.
Context  Ranolazine is a novel antianginal agent that reduces ischemia in patients with chronic angina but has not been studied in patients with acute coronary syndromes (ACS). Objective  To determine the efficacy and safety of ranolazine during long-term treatment of patients with non–ST-elevation ACS. Design, Setting, and Patients  A randomized, double-blind, placebo-controlled, multinational clinical trial of 6560 patients within 48 hours of ischemic symptoms who were treated with ranolazine (initiated intravenously and followed by oral ranolazine extended-release 1000 mg twice daily, n = 3279) or matching placebo (n = 3281), and followed up for a median of 348 days in the Metabolic Efficiency With Ranolazine for Less Ischemia in Non–ST-Elevation Acute Coronary Syndromes (MERLIN)-TIMI 36 trial between October 8, 2004, and February 14, 2007. Main Outcome Measures  The primary efficacy end point was a composite of cardiovascular death, myocardial infarction (MI), or recurrent ischemia through the end of study. The major safety end points were death from any cause and symptomatic documented arrhythmia. Results  The primary end point occurred in 696 patients (21.8%) in the ranolazine group and 753 patients (23.5%) in the placebo group (hazard ratio [HR], 0.92; 95% confidence interval [CI], 0.83-1.02; P = .11). The major secondary end point (cardiovascular death, MI, or severe recurrent ischemia) occurred in 602 patients (18.7%) in the ranolazine group and 625 (19.2%) in the placebo group (HR, 0.96; 95% CI, 0.86-1.08; P = .50). Cardiovascular death or MI occurred in 338 patients (10.4%) allocated to ranolazine and 343 patients (10.5%) allocated to placebo (HR, 0.99; 95% CI, 0.85-1.15; P = .87). Recurrent ischemia was reduced in the ranolazine group (430 [13.9%]) compared with the placebo group (494 [16.1%]; HR, 0.87; 95% CI, 0.76-0.99; P = .03). QTc prolongation requiring a reduction in the dose of intravenous drug occurred in 31 patients (0.9%) receiving ranolazine compared with 10 patients (0.3%) receiving placebo. Symptomatic documented arrhythmias did not differ between the ranolazine (99 [3.0%]) and placebo (102 [3.1%]) groups (P = .84). No difference in total mortality was observed with ranolazine compared with placebo (172 vs 175; HR, 0.99; 95% CI, 0.80-1.22; P = .91). Conclusions  The addition of ranolazine to standard treatment for ACS was not effective in reducing major cardiovascular events. Ranolazine did not adversely affect the risk of all-cause death or symptomatic documented arrhythmia. Our findings provide support for the safety and efficacy of ranolazine as antianginal therapy. Trial Registration  clinicaltrials.gov Identifier: NCT00099788   相似文献   
26.
High-dose immunosuppressive therapy (HDIT) with autologous hematopoietic stem cell transplantation (auto-HSCT) is a new and promising approach to the treatment of multiple sclerosis (MS) patients because currently there are no effective treatment methods for this disease. In this article, we present results of a prospective clinical study of efficacy of HDIT + auto-HSCT in MS patients. The following treatment strategies were employed in the study: "early," "conventional," and "salvage/late" transplantation. Fifty patients with various types of MS were included in this study. No toxic deaths were reported among 50 MS patients; transplantation procedure was well-tolerated by the patients. The efficacy analysis was performed in 45 patients. Twenty-eight patients achieved an objective improvement of neurological symptoms, defined as at least 0.5-point decrease in the Expanded Disability Status Scale (EDSS) score as compared to the baseline and confirmed during 6 months, and 17 patients had disease stabilization (steady EDSS level as compared to the baseline and confirmed during 6 months). The progression-free survival at 6 years after HDIT + auto-HSCT was 72%. Magnetic resonance imaging data were available in 37 patients before transplantation showing disease activity in 43.3%. No active, new, or enlarging lesions were registered in patients without disease progression. In conclusion, HDIT + auto-HSCT suggests positive results in management of patients with different types of MS. Identification of treatment strategies based on the level of disability, namely "early," "conventional," and "salvage/late" transplantation, appears to be feasible to improve treatment outcomes.  相似文献   
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28.
The liquid and lyophilized blood plasma of patients with benign or malignant thyroid nodules and healthy individuals were studied by terahertz (THz) time-domain spectroscopy and machine learning. The blood plasma samples from malignant nodule patients were shown to have higher absorption. The glucose concentration and miRNA-146b level were correlated with the sample’s absorption at 1 THz. A two-stage ensemble algorithm was proposed for the THz spectra analysis. The first stage was based on the Support Vector Machine with a linear kernel to separate healthy and thyroid nodule participants. The second stage included additional data preprocessing by Ornstein-Uhlenbeck kernel Principal Component Analysis to separate benign and malignant thyroid nodule participants. Thus, the distinction of malignant and benign thyroid nodule patients through their lyophilized blood plasma analysis by terahertz time-domain spectroscopy and machine learning was demonstrated.  相似文献   
29.
A novel method for the investigation of the chain‐end structure of poly(1,3‐pentadiene)s synthesized using the CF3COOD/TiCl4 initiating system is developed. It is shown for the first time that the content of trans‐1,2‐structures in the first monomer unit is considerably higher than the content of trans‐1,4‐structures, whereas the content of trans‐1,4‐units is substantially higher than trans‐1,2‐units for the polymer chain as a whole. Another important observation is that chain transfer to monomer is significant even at the earlier stages of the 1,3‐pentadiene polymerization (after 1 s of reaction). The very low functionality at the ω‐end (Fn (Cl) < 0.15) confirms the intensive chain transfer to monomer. This method is also applied for the estimation of the concentration of active species and the rate constant for propagation (k p) for the cationic polymerization of 1,3‐pentadiene using the CF3COOD/TiCl4 initiating system: rate constants for propagation, k p, of 1.5 × 103 and 3.3 × 103 L mol?1 min?1 are determined for 1,3‐pentadiene polymerization at 20 and –78 °C, respectively.

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30.
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