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541.
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543.
Ushio M Minor LB Della Santina CC Lasker DM 《Experimental brain research. Experimentelle Hirnforschung. Expérimentation cérébrale》2011,210(3-4):651-660
Unilateral vestibular lesions cause marked asymmetry in the horizontal vestibulo-ocular reflex (VOR) during rapid head rotations, with VOR gain being lower for head rotations toward the lesion than for rotations in the opposite direction. Reducing this gain asymmetry by enhancing ipsilesional responses would be an important step toward improving gaze stability following vestibular lesions. To that end, there were two goals in this study. First, we wanted to determine whether we could selectively increase VOR gain in only one rotational direction in normal monkeys by exposing them to a training session comprised of a 3-h series of rotations in only one direction (1,000°/s2 acceleration to a plateau of 150°/s for 1 s) while they wore 1.7 × magnifying spectacles. Second, in monkeys with unilateral vestibular lesions, we designed a paradigm intended to reduce the gain asymmetry by rotating the monkeys toward the side of the lesion in the same way as above but without spectacles. There were three main findings (1) unidirectional rotations with magnifying spectacles result in gain asymmetry in normal monkeys, (2) gain asymmetry is reduced when animals are rotated towards the side of the labyrinthectomy via the ipsilesional rotation paradigm, and (3) repeated training causes lasting reduction in VOR gain asymmetry. 相似文献
544.
Tetsukan Woo Koji Okudela Hideaki Mitsui Takuya Yazawa Nobuo ogawa Michihiko Tajiri Taketsugu Yamamoto Yasushi Rino Hitoshi Kitamura Munetaka Masuda 《International journal of clinical and experimental pathology》2011,4(1):32-42
CD133 is one of the most representative cancer stem cell markers. This study evaluated the potential prognostic value of CD133 expression in stage I lung adenocarcinomas (ADC). Tumors from 177 patients were immunohistochemically examined for CD133 expression, and their associations with disease recurrence were analyzed. Also, the potential prognostic value of combining CD133 expression with proliferating activity measured by immunohistochemical expression of Ki-67 and vessel involvement was evaluated. CD133 high expressers showed a significantly higher risk of recurrence than CD133 low expressers: 5-year disease-free survival (DFS) rate 77.2% vs. 95.1% (p=0.004), adjusted Hazard ratio (HR) 4.37, 95% Confidence Interval (CI) 1.30-14.71 (p=0.017). CD133 high expressers having strong proliferating activity and/or with vessel invasion showed a higher risk of recurrence: 5-year DFS rate 66.5% in CD133 high/Ki-67 high expressers vs. 93.2% in the other types (p<0.001), adjusted HR 8.39, 95% CI 2.65-26.54 (p<0.001): 5-year DFS rate 51.0% in CD133 high expressers with vessel invasion vs. 92.9% in the other types (p<0.001), adjusted HR 4.50, 95% CI 1.51-13.34 (p=0.007): 5-year DFS rate 53.9% in CD133 high/Ki-67 high expressers with vessel invasion vs. 91.2% in the other types (p<0.001), adjusted HR 9.32, 95% CI 3.42-25.39 (p<0.001). In conclusion, the level of CD133 expression is an independent prognostic marker and its combination with proliferating activity and/or vessel invasion could have excellent prognostic value to predict postoperative recurrence in patients with stage I lung ADC. 相似文献
545.
Sato H Sakaeda M Ishii J Kashiwagi K Shimoyamada H Okudela K Tajiri M Ohmori T Ogura T Woo T Masuda M Hirata K Kitamura H Yazawa T 《Pathology international》2011,61(1):19-27
Gene silencing by promoter hypermethylation plays an important role in molecular pathogenesis. We previously reported that insulin-like growth factor (IGF) binding protein-4 (IGFBP-4), which inhibits IGF-dependent growth, is expressed via early growth response-1 (EGR-1) and is often silenced in cultivated lung cancer cells. The purpose of the present study was to clarify clinicopathological factors associated with IGFBP-4 gene silencing in lung adenocarcinomas. Seventy-six surgically resected adenocarcinomas (20 well-, 35 moderately-, and 21 poorly-differentiated) were subjected to methylation-specific polymerase chain reaction (PCR) analysis for EGR-1-binding sites located in the IGFBP-4 promoter and immunohistochemistry for IGFBP-4, EGR-1, and Ki-67. Thirty-two adenocarcinomas (42%) revealed IGFBP-4 promoter hypermethylation, and the severity inversely correlated with the level of IGFBP-4 expression (P < 0.0001) and tumor differentiation (well versus poor, P = 0.0278; well/moderate versus poor, P = 0.0395). Furthermore, there was a negative correlation between Ki-67 labeling index and IGFBP-4 expression (P = 0.0361). These findings suggest that the expression of IGFBP-4 in adenocarcinoma cells in vivo is downregulated by epigenetic silencing in association with tumor differentiation, resulting in disruption of the mechanism of IGFBP-4-mediated growth inhibition. 相似文献
546.
The laryngeal mask airway has been used increasingly in clinics but is seldom applied in anesthesia for oral surgery, as the
mask occupies the middle of the mouth and tends to obstruct the surgical field. Here, we report the successful placement and
usage of a nasal flexible laryngeal mask airway (FLMA) in an oral surgical procedure. Fifteen patients undergoing dental procedures
under general anesthesia were studied. We clinically applied a previously reported method for inserting an FLMA with some
modifications. There was no significant bleeding from the intubated nostril in any of the patients. None of the patients complained
of sore throat, coughing, hoarseness, or any discomfort in the nose. Although we anticipate that further refinements of the
technique may be possible and that the safety of this method using a nasal FLMA needs to be assessed in a greater number of
patients, in this preliminary study we provide a proof-of-principle demonstration of the efficacy of nasal LMA ventilation
as a method of airway management for oral surgery. 相似文献
547.
548.
The aim of this study was to investigate whether steroid administration would increase the risk of postoperative infection. Sixty adults who underwent elective cardiac surgery under cardiopulmonary bypass were prospectively randomized into two groups. Thirty-one patients received hydrocortisone (50 mg x kg(-1)) before and after cardiopulmonary bypass, the other 29 served as controls. Various hemodynamic and pulmonary measurements were obtained perioperatively, and the white blood cell counts and levels of C-reactive protein were checked up to the 14(th) postoperative day. Steroid administration did not have any favorable effects during the perioperative period. Re-administration of antibiotics was needed in 7 patients (22.6%) after the 7(th) postoperative day in the steroid group, and in 3 (10.3%) in the control group. The peak white cell counts and C-reactive protein levels after the 7(th) postoperative day were significantly higher in the steroid group. Steroid administration offered no clinical benefit to patients undergoing cardiac surgery with cardiopulmonary bypass, and it may encourage minor infections in the late postoperative period. 相似文献
549.
Fish plasma/serum contains multiple IGF binding proteins (IGFBPs), although their identity and physiological regulation are poorly understood. In salmon plasma, at least three IGFBPs with molecular masses of 22, 28 and 41 kDa are detected by Western ligand blotting. The 22 kDa IGFBP has recently been identified as a homolog of mammalian IGFBP-1. In the present study, an RIA for salmon IGFBP-1 was established and regulation of IGFBP-1 by food intake and temperature, and changes in IGFBP-1 during smoltification, were examined. Purified IGFBP-1 from serum was used for as a standard, for tracer preparation and for antiserum production. Cross-linking (125)I-labelled IGFBP-1 with salmon IGF-I eliminated interference by IGFs. The RIA had little cross-reactivity with salmon 28 and 41 kDa IGFBPs (< 0.5%) and measured IGFBP-1 levels as low as 0.1 ng/ml. Fasted fish had significantly higher IGFBP-1 levels than fed fish (21.6 +/- 4.6 vs 3.0 +/- 2.2 ng/ml). Plasma IGFBP-1 was measured in individually tagged 1-year-old coho salmon reared for 10 weeks under four different feeding regimes as follows: high constant (2% body weight/day), medium constant (1% body weight/day), high variable (2% to 0.5% body weight/day) and medium variable (1% to 0.5% body weight/day). Fish fed with the high ration had lower IGFBP-1 levels than those fed with the medium ration. Circulating IGFBP-1 increased following a drop in feeding ration to 0.5% and returned to the basal levels when feeding ration was increased. Another group of coho salmon were reared for 9 weeks under different water temperatures (11 or 7 degrees C) and feeding rations (1.75, 1 or 0.5% body weight/day). Circulating IGFBP-1 levels were separated by temperature during the first 4 weeks; a combined effect of temperature and feeding ration was seen in week 7; only feeding ration influenced IGFBP-1 level thereafter. These results indicate that IGFBP-1 is responsive to moderate nutritional and temperature changes. There was a clear trend that circulating IGFBP-1 levels were negatively correlated with body weight, condition factor (body weight/body length(3) x 100), growth rates and circulating 41 kDa IGFBP levels but not IGF-I levels. During parr-smolt transformation of coho salmon, IGFBP-1 levels showed a transient peak in late April, which was opposite to the changes in condition factor. Together, these findings suggest that salmon IGFBP-1 is inhibitory to IGF action. In addition, IGFBP-1 responds to moderate changes in dietary ration and temperature, and shows a significant negative relationship to condition factor. 相似文献
550.