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Background: The role of speckle tracking in the assessment of right atrial (RA) deformation dynamics has not been established yet. The reference ranges of RA longitudinal strain indices were measured by speckle tracking in a population of normal subjects. Methods: In 84 healthy individuals, peak atrial longitudinal strain (PALS), peak atrial contraction strain (PACS), and time to peak longitudinal strain (TPLS) were measured using a six‐segment model for the RA. Strain rate (SR) was also measured starting from the QRS‐wave onset, peak positive (x‐wave), first peak negative (y‐wave), and second negative peak (z‐wave). The time from the QRS onset was measured to each wave peak. Results: Adequate tracking quality was achieved in 64% of segments analyzed. Inter‐ and intraobserver variability coefficients of measurements ranged between 6% and 11%. Global PALS was 49 ± 13%, global TPLS was 363 ± 59 msec, x‐wave was 2.12 ± 0.58 sec?1, y‐wave was ?1.91 ± 0.63 sec?1, and z‐wave was ?2.18 ± 0.78 sec?1. Conclusion: Speckle tracking is a feasible technique for the assessment of longitudinal myocardial RA deformation. Reference ranges of strain indices were reported. (Echocardiography 2012;29:147‐152)  相似文献   
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5q14.3 deletions including the MEF2C gene have been identified to date using genomic arrays in patients with severe developmental delay or intellectual disability, stereotypic behavior, epilepsy, cerebral malformations and a facial gestalt not really distinctive though characterized by broad and/or high, bulging forehead, upslanting palpebral fissures, flat nasal root and bridge, small, upturned nose, hypotonic small mouth resulting in cupid bow/tented upper lip. MEF2C mutations have been also identified in patients with overlapping phenotype so that it is considered the gene responsible for the 5q14.3 deletion syndrome. To date, one single duplication including MEF2C has been reported in a patient with intellectual disability but its clinical significance remains uncertain also because of the large size of the imbalance. Here we present two further patients with 5q14.3 duplications including MEF2C. Their phenotype indeed suggest the pathogenic effect of the MEF2C duplication although other duplicated genes also brain expressed might contribute to the clinical features. In none of them a clear-cut syndrome can be identified. A comparison between MEF2C deleted/mutated and duplicated patients is also presented.  相似文献   
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Portopulmonary hypertension has been reported in 2% to 9% of candidates for liver transplantation (OLT). If it is moderate to severe, it represents a contraindication to the procedure until pulmonary vasodilatative therapy has been optimized. We report the case of a 43-year-old man, scheduled for OLT due to alcoholic cirrhosis with hemosiderosis. His Model for End-Stage Liver Disease was 25 at that time. The preoperative evaluation showed a severe alteration of diffusion (pO2 68 mm Hg), without hepatopulmonary syndrome or portopulmonary hypertension (PPH) upon basal and dobutamine stress echocardiography. At the beginning of the OLT the hemodynamic profile showed mean pulmonary artery pressure (mPAP) 38 mm Hg, wedge pressure (WP) 19 mm Hg, cardiac output (CO) 9.1 L/min, pulmonary vascular resistance (PVR) 166 dyne s/cm5, transpulmonary gradient (TPG) 19 mm Hg, which lead us to promptly initiate inhaled nitric oxide (iNO) and intravenous epoprostenol 2 to 5 ng/kg/min. Upon graft reperfusion the hemodynamic profile was: mPAP 47 mm Hg, WP 23 mm Hg, CO 14.2 L/min, PVR 135 dyne s/cm5, TPG 24 mm Hg, and at the end of surgery, mPAP 39 mm Hg, WP 20 mm Hg, CO 10.6 L/min, PVR 123 dyne s/cm5, TPG 19 mm Hg. On postoperative day (POD) 3, we observed severe worsening of PPH: mPAP 60 mm Hg, WP 10 mm Hg, CO 9.8 L/min, PVR 395 dyne s/cm5, TPG 50 mm Hg even with maximal pulmonary vasodilatatory therapy (ambrisentan 5 mg, intravenous sildenafil 20 mg × 3 and epoprostenol 22 ng/kg/min, iNO). Severe acute respiratory distress syndrome (ARDS) was presents. Therefore we decided to begin veno-venous extracorporeal membrane oxygenation (v-v ECMO) to correct the hypoxic vasoconstriction. Subsequent weaning from inotropic support with iNO and epoprostenol was possible on POD 7 due to mPAP 42 mm Hg, WP 15 mm Hg, CO 7.9 L/min, PVR 273 dyne s/cm5, and TPG 27 mm Hg. On POD 11 he was weaned from ECMO due to: mPAP 40 mm Hg, WP 16 mm Hg, CO 6.5 L/min, PVR 295 dyne s/cm5 and TPG 24 mm Hg. The patient was extubated on POD 17. The cardiac catheterization 1 month after OLT showed: mPAP 28 mm Hg, WP 13 mm Hg, CO 5.4 L/min, PVR 220 dyne s/cm5 and TPG 15 mm Hg. ECMO rescue therapy in this “extreme” case allowed us to correct hypoxemia responsible for worsening of pulmonary hypertension allowing time to reach the goal of vasodilatatory therapy.  相似文献   
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We retrospectively analysed 78 patients with relapsed (n?=?38), primary refractory (n?=?34) or untreated (n?=?6) acute myeloid leukaemia (AML) who underwent allogeneic HSCT at our Institution between 2002 and 2011, to verify outcome and to identify factors that can affect long-term outcome. Myeloablative conditioning regimens were used in 48 patients (24 siblings, 24 matched unrelated donor (MUD)), while 30 patients (18 siblings, 12 MUD) received reduced-intensity conditioning. Acute graft versus host disease (GVHD) developed in 37 (47?%) patients, while chronic GVHD occurred in 19 of the 65 evaluable patients (29?%). With a median follow-up time of 5?years, 13 of 78 patients (17?%) are alive and in complete remission (CR), while 64 have died. Cause of death was disease recurrence in 37 patients (58?%), infection in ten patients (16?%) and GVHD in six (9?%). One-year non-relapse mortality was 35?%. In multivariate analysis, performance status ≥80?% WHO and a full-matched donor were associated with a better outcome: these two variables allowed for risk stratification, identifying three groups with significantly different survival after transplant (P?=?0.0001). Considering post-transplant variables, only CR at recovery and development of cGVHD were correlated with a longer survival. Our data confirm the capacity of allogeneic transplant to prolong survival in a significant proportion of extremely high-risk AML patients.  相似文献   
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Since recent findings suggest a relationship between reduction in adipose tissue blood flow (ATBF) and metabolic or vascular complications in obese patients (Ob-pts), increase in ATBF may be considered as a further goal in the treatment of obesity, besides fat mass reduction. Therefore, this preliminary study aimed at assess subcutaneous ATBF and vasomotion in morbidly obese patients and whether sustained weight loss induced by Roux-en-Y gastric bypass (RYGB) affects the same parameters. Using laser-Doppler flowmetry (LDF) and spectral Fourier analysis, subcutaneous ATBF was measured and subcutaneous ATBF oscillations (ATBF-O) were analyzed - within three frequency intervals related to vasomotion - in 16 Ob-pts, before and about one year after RYGB, and in 10 lean, healthy control subjects (CS). Before RYGB, Ob-Pts showed an important reduction in subcutaneous ATBF compared to CS (4.8 ± 2.7 PU vs 79.9 ± 34.5 PU, respectively; p < 0.0001), as well as higher normalized power spectral density (N-PSD) values of subcutaneous ATBF-O, - related to vasomotion. One year after RYGB, sustained weight loss in Ob-pts was associated with a slight but significant increase in subcutaneous ATBF (10.0 ± 6.6 PU, p < 0.05) and with almost complete normalization in N-PSD values of ATBF-O, related to vasomotion, compared to before RYGB. The slight subcutaneous ATBF increase, we observed in Ob-pts after sustained weight loss, moves toward a desirable goal. This finding suggests verifying whether an even more sustained weight loss in Ob-pts could determine a greater increase in subcutaneous ATBF and/or, more importantly, it could also determine a significant increase in visceral ATBF.  相似文献   
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