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991.
BACKGROUND: Circumferential pulmonary vein ablation (CPVA) is an effective treatment for atrial fibrillation (AF). Accurate left atrial (LA) mapping is essential for creating lesions at the LA-pulmonary vein (PV) junction, avoiding PV stenosis. OBJECTIVES: The purpose of this study was to establish whether endocardial impedance varies within the LA and PVs and whether it is a useful tool for mapping and ablation. METHODS: Pilot Phase: Three-dimensional LA maps were created using CARTO. Impedance (Z) was measured using a radiofrequency generator at multiple points in the LA, PV ostia (PVO), and deep PVs in 79 patients undergoing their first AF ablation (group 1) and 29 patients undergoing repeat CPVA (group 2). Prospective Phase: In an additional 20 patients, using pilot phase data, one operator defined catheter tip location as either LA or PVO based on CARTO and fluoroscopy. A second operator blinded to CARTO simultaneously did the same based on impedance at 15 +/- 4 points per patient. RESULTS: Group 1: Z(LA) was 99.4 +/- 9.0 omega. Z(PVO) was higher (109.2 +/- 8.5 omega), rising further as the catheter advanced into deep PV (137 omega +/- 18). Z(PVO) differed from Z(LA) by 9 +/- 4 omega. Group 2 had a lower Z(LA) and Z(PVO) compared with group 1 (P <.05). Impedance monitoring differentiated between LA and PVO, with 91% specificity and sensitivity, 96% positive predictive value, and 81% negative predictive value. At 3-month follow-up, no patients had evidence of PV stenosis on magnetic resonance imaging. CONCLUSION: Impedance mapping reliably identifies the LA-PV transitional zone, facilitating AF ablation, and its use is associated with a low incidence of PV stenosis.  相似文献   
992.
Objective Neprilysin (neutral endopeptidase, 3:4:24:11, CD10) (NEP) is a Zn metallopeptidase linked to controlling inflammation through the degradation of neuropeptides involved in neurogenic inflammation of chronic rheumatic diseases. The aim of our study was to evaluate circulating activity and cellular expression of NEP in the plasma of 58 children with juvenile idiopathic arthritis (JIA) and 52 controls. In 20 subjects requiring local steroid injection, NEP was measured in synovial fluid.Methods Plasma and synovial NEP were evaluated using a fluorimetric technique. Neprilysin, expressed as the antigen CD10, was determined on circulating and synovial fluid cells as mean fluorescence intensity (MFI) and as percentage of positive cells by two-color immunofluorescence.Results Circulating NEP levels were lower in JIA patients than in controls (42.0±16.6 vs 76.5±24 pmol/ml per min, P<0.001), while synovial fluid NEP values were higher than circulating levels (241.4±86.2 vs 40±15.3 pmol/ml per min, P<0.001). In monocytes, the percentage of CD10-positive circulating cells and the MFI in JIA were lower than in controls (11.6±5.2% vs 41.4±13%, P<0.001 and 18.1±7.5 vs 31.2±5.4, P<0.05, respectively). On synovial monocytes, the percentage of CD10-positive cells and the MFI were higher than on circulating monocytes (35.2±14.6% vs 9.1±2.4%, P<0.001 and 66.4±5.4 vs 22.8±14.7, P<0.001, respectively).Conclusions The downregulation of CD10 expression in monocytes and the reduction in NEP activity may be linked to the enzymes role in the control of peptides involved in the inflammation. The increased levels of NEP, MFI, and CD10-positive monocytes in synovial fluid, even though in plasma, might reflect a reactive effort to control synovial proliferation.  相似文献   
993.
Since gastro-entero-pancreatic endocrine tumors are rare and heterogeneous diseases, their prognosis and long-term survival are not well known. This study aimed at identifying prognostic factors and assessing long-term survival in gastro-entero-pancreatic endocrine tumors. A total of 156 patients enrolled. Prognostic factors were determined by univariate/multivariate analysis; survival rates were assessed by the Kaplan-Meier method. The tumors were non-functioning in 59.6% of patients, and originated from the pancreas in 42.9%. At diagnosis, 64.3% of patients had metastases. The tumors were well differentiated in 89.6% of patients. Ki67 was >2% in 39.6% of patients. Primary tumor size was >3 cm in 49.6% of cases studied. For the univariate analysis, the negative prognostic factors were: pancreatic origin (rate ratio 4.64, P = 0.0002), poorly differentiated tumor (rate ratio 7.70, P = 0.0001), primary tumor size >3 cm (rate ratio 4.26, P = 0.0009), presence of distant metastases (liver: rate ratio 5.88, P = 0.01; distant extra-hepatic: rate ratio 13.41, P = 0.0008). The pancreatic site, the poor degree of differentiation and the distant metastases were confirmed as negative prognostic factors at multivariate analysis. Overall 5-year survival rate was 77.5%. Survival rates differed according to: primary tumor site (62% for pancreatic vs 89.9% for gastrointestinal tract, P = 0.0001) and size (65.7% for >3 cm vs 88.8% for < or = 3 cm, P = 0.0003), degree of differentiation (22% for poor vs 86.8% for good, P < 0.0001), Ki67 (53.5% for > 2% vs 90.1% for < or = 2%, P = 0.003), metastases (96.1, 77, 73.3 and 50.1% for absent, local, liver and distant extra-hepatic metastases respectively), age at diagnosis (85.3% for < or = 50 years vs 70.3% for > 50 years, P = 0.03). Although 64.3% of gastro-entero-pancreatic endocrine tumors present metastases at diagnosis, the 5-year survival rate is 77.5%. Pancreatic site, a poor degree of tumor cell differentiation and distant extra-hepatic metastases are the major negative prognostic factors.  相似文献   
994.
AIMS: The majority of tissue Doppler indexes proposed to predict left ventricular (LV) reverse remodelling in cardiac resynchronization therapy (CRT) reflects LV asynchrony as assessed in ejection phase. We evaluated the predictive value of a new strain-imaging parameter reflecting the total amount of time spent by 12 LV segments in contracting after aortic valve closure. METHODS AND RESULTS: Fifty-nine patients who fulfilled current treatment recommendations were studied before and 6 months after CRT. Time to tissue Doppler systolic peak velocity (Ts) and time exceeding aortic closure (ExcT) in strain curves were measured in 12 LV segments. Ts standard deviation (Ts-SD) and sum of ExcT of overall 12 LV segments (oExcT) were analysed. After 6 months, responders were defined according to > or =15% LV end-systolic volume reduction. Responders (47%) when compared with non-responders (53%) had significantly higher baseline Ts-SD and oExcT values. Receiver operating characteristic (ROC) curve analysis demonstrated that an optimal cutoff value of 760 ms for oExcT yielded 93.5% sensitivity and 82.8% specificity. For Ts-SD at the cutoff of 32 ms, 82% sensitivity and 39% specificity were obtained. Area under ROC was significantly larger for oExcT than for Ts-SD. CONCLUSION: o-ExcT is able to predict LV reverse remodelling after CRT.  相似文献   
995.

Aims

The most recent European guidelines have proposed new definitions of pulmonary hypertension (PH) in left heart disease, to better approach the characteristics required to reflect the presence of pulmonary vascular disease. The purpose of this study was to assess whether different haemodynamic definitions of post‐capillary PH imply a different reversibility of PH in response to acute vasodilator administration in heart failure patients with reduced ejection fraction and PH (HFrEF‐PH).

Methods and results

Right heart catheterization and reversibility testing was performed in 156 HFrEF‐PH patients. Patients were classified as combined post‐capillary and pre‐capillary pulmonary hypertension (Cpc‐PH) vs. isolated post‐capillary pulmonary hypertension (Ipc‐PH) and on the basis of diastolic pulmonary gradient (DPG) ≥ 7 vs. < 7 mmHg or of transpulmonary gradient (TPG) >12 vs. ≤12 mmHg. After vasodilator administration, Cpc‐PH patients showed a greater per cent improvement in pulmonary vascular resistance (PVR), DPG and TPG as compared with Ipc‐PH patients (all Pint < 0.001); only pulmonary compliance (PCa) improved less in Cpc‐PH than in Ipc‐PH patients (Pint = 0.007). However, despite vasodilatation, Cpc‐PH patients remained in an unfavourable portion of the inverse hyperbolic relationship between PVR and PCa. The number of patients in whom PVR was reduced below 2.5 wood units was similar in Cpc‐PH, DPG ≥7 mmHg and TPG >12 mmHg groups (28.3, 26.7 and 18.9%, respectively).

Conclusion

Although substantial improvements in PVR, DPG and TPG were observed in Cpc‐PH patients after acute vasodilator administration, this response was associated with persistent abnormalities in the PVR vs. PCa relationship. The link between baseline right heart haemodynamics and pulmonary vascular disease remains elusive.
  相似文献   
996.
997.
998.
Therapy‐related myeloid neoplasms (t‐MN) are a complication of cytotoxic treatment for primary tumors and autoimmune diseases. We report data on 277 t‐MN patients, recruited between 1999 and 2013 by the Italian Network on Secondary Leukemias (104 retrospectively and 173 prospectively registered). Median age at t‐MN diagnosis was 64 years (range, 21–87). Most frequent primary malignancies (PMs) were lymphoproliferative diseases and breast cancer. One hundred and thirty‐three patients had received chemotherapy (CHT), 43 patients radiotherapy (RT), and 101 patients combined CHT/RT for PM. Median time between cytotoxic treatment and t‐MN was 5.7 years, with t‐MN following RT alone associated with significantly longer latency, compared to CHT or combined CHT/RT (mean, 11.2 vs. 7.1 years, P = 0.0005). The addition of topoisomerase‐II inhibitors to alkylating agents was associated with shorter latency compared to alkylating agents alone (median, 6 vs. 8.4 years, P = 0.02). Median survival was 14.6 months from t‐MN diagnosis, and was significantly longer in patients treated with allogeneic stem cell transplantation. Significant factors for survival at the multivariable analysis included age, adverse karyotype, and degree of anemia. Our data underline the prognostic importance of karyotype and age in t‐MN, similar to de novo acute myeloid leukemia. Treatment approaches should not preclude the use of conventional treatments for younger t‐MN patients, including allogeneic stem cell transplantation as potentially curative approach. Am. J. Hematol. 90:E80–E85, 2015. © 2015 Wiley Periodicals, Inc.  相似文献   
999.
Nilotinib is a second-generation tyrosine kinase inhibitor that has been approved for the first-line treatment of chronic-phase chronic myeloid leukemia, based on the results of a prospective randomized study of nilotinib versus imatinib (ENESTnd). Apart from this registration study, very few data are currently available on first-line nilotinib treatment. We report here the long-term, 6-year results of the first investigator-sponsored, GIMEMA multicenter phase 2, single-arm trial with nilotinib 400 mg twice daily as first-line treatment in 73 patients with chronic-phase chronic myeloid leukemia. Six-year overall survival and progression-free survival rates were 96%, with one death after progression to blast phase. At 6 years, 75% of the patients were still on nilotinib. The cumulative incidence of major molecular response was 98%; only one patient had a confirmed loss of major molecular response. The cumulative incidence of deep molecular response (MR 4.0) was 76%. Deep molecular response was stable (≥2 years) in 34% of these patients. Cardiovascular adverse events, mainly due to arterial thrombosis, occurred in 11/73 patients (15%), after 24 to 76 months of therapy. They were more frequent in elderly patients, and in those with baseline cardiovascular risk factors. None was fatal, although there was a relevant morbidity. This is the study with the longest follow-up of a high dose of nilotinib (400 mg twice daily): it highlights the high efficacy and the cardiovascular toxicity of the drug (CTG.NCT.00481052).  相似文献   
1000.
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