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71.
72.
前锯肌下部肌皮瓣移植的应用解剖 总被引:1,自引:1,他引:0
目的:为前锯肌下部肌皮瓣移植提供解剖学基础。方法:在25具(50侧)成人尸体标本上,对前锯肌下部的形态、血供和神经支配进行了应用解剖学观测。结果:前锯肌下部的血供主要来自胸背动脉的前锯肌支,外径1.3±0.2mm,伴行静脉外径1.5±0.2mm,长4.9±1.1cm;由胸长神经支配,其横径为1.7±0.4mm,神经干长7.7±1.4cm。结论:以胸背血管及前锯肌支为血管蒂和胸长神经为蒂可切取前锯肌下部12.0cm×9.0cm的肌皮瓣,修复较大创面或重建肌动力 相似文献
73.
The sudden appearance of prolactin-releasing cells during the early postnatal period of the rat is initiated by a small milk-borne
peptide. Depriving newborn rats of this early milk factor severely retards mammotrope differentiation during the neonatal
period. In the present work, we extend our study of early milk deprivation to the adult. To this end, newborn litters were
crossfostered onto mothers that had given birth the same day or one week earlier in order to deprive pups in the latter group
of early milk. At 5, 15, and 30 d of age, rats deprived of such milk had decreased percentages of mammotropes (as measured
by reverse hemolytic plaque assay, RHPA) when compared to nondeprived animals (P<0.05). By 45 d, the percentage of mammotropes was similar for the two crossfostered groups (P>0.1) and this persisted through d 60. Subsequently, we assessed the secretory capacity of mammotropes from 60-d old rats
to secretagogues and found that early milk deprivation had no effect on basal prolactin release (P>0.1), but that it augmented
hormone secretion evoked by thyrotropin-releasing hormone (TRH, 100 nM; P<0.01). The inhibitory response to dopamine (DA; 1 μM) and the stimulatory response to angiotensin II (AGII; 100 nM) were not altered by early milk deprivation (P>0.1). Taken together, these results demonstrate that factors in milk from early lactation are required for normal mammotrope
differentiation, and that the delay induced by early milk deprivation leads to altered secretory function of mammotropes in
adult animals. 相似文献
74.
TAKASHI OKI M.D. NOBUO FUKUDA M.D. TOMOTSUGU TABATA M.D. ARATA IUCHI M.D. MASATO TANIMOTO M.D. KAZUYO MANABE M.D. YOSHIMI KAGEJI M.D. MIWA SASAKI M.D. SUSUMU ITO M.D. 《Echocardiography (Mount Kisco, N.Y.)》1995,12(4):351-358
Transesophageal echocardiography was conducted to determine the systolic pattern of the anterior mitral leaflet in patients with flat chest, and to differentiate it from that associated with mitral valve prolapse. The fronto-sagittal index (an index of chest flattening) was determined in 50 subjects using chest radiographs, and was used to classify them into a flat chest group (index < 0.38, n = 28) and a normal chest group (index ≥ 0.38, n = 22). We then used transesophageal echocardiography to examine the anterior leaflet in these subjects. A significant positive correlation was observed between the fronto-sagittal index and the short-to long-axis diameter ratio of the left ventricle in all patients. These parameters, and the left atrial dimension were lower in the flat than the normal chest group. The clear zone area of the anterior leaflet during mid-to late-systole was significantly larger in the flat chest group. However, no intergroup differences existed in the rough zone area of the anterior leaflet or in the middle scallop area of the posterior leaflet. Mitral regurgitation was observed in 20 and 12 subjects in the flat and normal chest groups, respectively. The maximum mitral regurgitant area did not differ between the two groups. The clear zone area of the anterior leaflet increased significantly following inhalation of amyl nitrite in 22 subjects of both groups, but the other areas did not increase. The mitral regurgitant area decreased or disappeared after amyl nitrite at a similar rate in each group. Thus, the decrease in the antero-posterior dimension of the thorax in subjects with flat chest affects the systolic pattern of the clear zone of the anterior leaflet more than that of the rough zone of the anterior leaflet or the posterior leaflet. This systolic pattern in such patients differs from that associated with mitral valve prolapse. 相似文献
75.
Devices that are pinned to the tibia to tension an anterior cruciate ligament (ACL) graft produce joint reaction loads that in turn can affect the maintenance of graft initial tension after tibial fixation and hence knee anterior-posterior (AP) load-displacement. However, the effect of these devices on AP load-displacement is unknown. Our objectives were to determine whether tensioning by device versus tensioning by hand causes differences in AP load-displacement and intraarticular graft tension for two commonly used tibial fixation devices: a bioresorbable interference screw and a WasherLoc. AP load-displacement and intraarticular graft tension were measured in 20 cadaveric knees using a custom arthrometer. An initial tension of 110 N was applied to a double-looped tendon graft with the knee at extension using a tensioning device pinned to the tibia and a simulated method of tensioning by hand. After inserting the tibial fixation device, the 134 N anterior limit (i.e., anterior position of the tibia with respect to the femur with a 134 N anterior force applied to the tibia) and 0 N posterior limit (i.e., AP position of the tibia relative to the femur with a 0 N force applied to the tibia) were measured with the knee in 25 degrees flexion. Intraarticular graft tension was measured at extension. These limits and intraarticular graft tension were also measured after cyclically loading the knee 300 times. Compared to a simulated method of tensioning by hand, tensioning with a device pinned to the tibia did not decrease the 134 N anterior limit and did not cause posterior tibial translation. However, intraarticular graft tension was maintained better with a tensioning device pinned to the tibia for the Washerloc, but not the interference screw. For two commonly used tibial fixation devices, a tensioning device pinned to the tibia does not improve AP load-displacement at 25 degrees flexion over tensioning by hand when the graft is tensioned at full extension, but does improve the maintenance of intraarticular graft tension for the Washerloc. 相似文献
76.
目的探讨交叉韧带重建术中可吸收挤压螺钉的使用方法和疗效。方法总结53例交叉韧带重建病例使用可吸收挤压螺钉的情况,在术中、术后并发症、术后康复、膝关节功能状况等方面进行回顾性分析。结果三例出现韧带切割现象。两例股骨侧螺钉拧入后导引针无法拔出。一例挤压螺钉断裂。术后Lysholm评分平均92.4±4.1。结论交叉韧带重建术中使用可吸收挤压螺钉固定的方法固定牢固,术后恢复快,利于早期康复。 相似文献
77.
Stefan Tigges M.D. B. J. Manaster M.D. Ph.D. Gordon Carson M.D. 《Emergency radiology》1996,3(3):105-112
Although magnetic resonance imaging is the most accurate imaging method of evaluating the anterior cruciate ligament, several
plain radiographic signs suggestive of anterior cruciate ligament injury have been described. Plain radiographs also play
an important role in evaluating anterior cruciate ligament reconstruction. 相似文献
78.
C. J. Snijders PhD A. Vleeming PhD R. Stoeckart PhD 《Clinical biomechanics (Bristol, Avon)》1993,8(6):285-294
This study deals primarily with the stability of the base of the spine. The sacroiliac joints are vulnerable to shear loading on account of their predominantly flat surfaces. This raises the question of what mechanisms are brought into action to prevent dislocation of the sacroiliac joints when they are loaded by the weight of the upper part of the body and by trunk muscle forces. First a model is introduced to compare load transfer in joints with spherical and with flat joint surfaces. Next we consider a biomechanical model for the equilibrium of the sacrum under load, describing a self-bracing effect that protects the sacroiliac joints against shear according to ‘the sacroiliac joint compression theory’, which has been demonstrated in vitro. The model shows joint stability by the application of bending moments and the configuration of the pelvic arch. The model includes a large number of muscles (e.g. the gluteus maximus and piriformis muscles), ligaments (e.g. the sacrotuberous, sacrospinal, and dorsal and interosseous sacroiliac ligaments) as well as the coarse texture and the ridges and grooves of the joint surfaces. 相似文献
79.
Short-survival, sequential, and long-survival thymidine radiograms of rat embryos, fetuses, and young pups were analyzed in order to examine the time of origin, settling pattern, and neuroepithelial site of origin of the anterior thalamic nuclei--the lateral dorsal (lateral anterior), anterodorsal, anteroventral and anteromedial nuclei--and of two rostral midline structures--the anterior paraventricular and paratenial nuclei. The neurons of the lateral dorsal nucleus are generated over a 3-day period between days E14-E16 and their settling pattern displays a combined lateral-to-medial and dorsal-to-ventral neurogenetic gradient. The bulk of the neurons of the anteroventral nucleus are generated over a 3-day period between days E15-E17 and settle with an oblique lateral-to-medial and ventral-to-dorsal neurogenetic gradient. The bulk of the neurons of the anteromedial nucleus are generated over a 2-day period between days E16-E17 and show the same settling pattern as the anteroventral nucleus. The neurons of the anterodorsal nucleus are generated over a 3-day period between days E15-E17 and show a lateral-to-medial neurogenetic gradient. The bulk of the neurons of the central part and lateral part of the paraventricular nucleus are generated over a 2-day period (E16-E17 and E17-E18, respectively) and each part displays a ventral-to-dorsal neurogenetic gradient. Finally, the bulk of the neurons of the paratenial nucleus are generated over a 4-day period between days E15-E18 and settle with a lateral-to-medial neurogenetic gradient. Observations are presented that the anterior thalamic nuclei, constituting the distinct "limbic thalamus," derive from a discrete neuroepithelial source. This is the crescent-shaped germinal matrix lining the diencephalic (medial) wall of the hitherto unrecognized anterior transitional promontory, which we call the anterior thalamic neuroepithelial lobule. On day E16 three migratory streams leave the anterior neuroepithelial lobule and, on the basis of their labeling pattern in relation to the neurogenetic gradients of the anterior thalamic nuclei, they are identified, from dorsal to ventral, as the putative migratory streams of the anterodorsal, anteroventral, and lateral dorsal nuclei. On day E17 the putative migratory stream of the anteromedial nucleus appears to leave the same neuroepithelial region that on the previous days was the source of the anteroventral nucleus. Dorsally, two neuroepithelial patches persist after day E17 and these are identified as the putative cell lines of the anterior paraventricular and paratenial nuclei. 相似文献
80.
对比骨桥栓桩与界面螺钉在膝关节前交叉韧带断裂重建术中的临床价值。方法 回顾性分析2019年7月—2020年12月我院700例在关节镜下行前交叉韧带重建手术的患者,股骨隧道均以横穿钉固定。按移植物胫骨端固定方式分为骨桥栓桩组(380例)及界面螺钉组(320例)。对比两组手术时间、切口长度、住院时间及费用;比较两组术后3个月、12个月胫骨隧道大小、膝关节功能Lyshlom评分及术后12个月关节松弛度。结果 两组患者手术时间、胫骨端切口长度、住院时间比较差异均无统计学意义(P>0.05),但骨桥栓桩组手术费用显著低于界面螺钉组(P<0.05)。术后3个月、12个月两组患者胫骨隧道大小、膝关节功能Lyshlom评分及关节松弛度比较差异均无统计学意义(P>0.05),但随着时间的延长,两组患者隧道均有不同程度的扩大(P<0.05)。结论 对于行关节镜下前交叉韧带重建术的患者,采用骨桥栓桩胫骨端固定方式可取得与界面螺钉固定相当的临床效果,但骨桥栓桩固定更具医疗经济优势,是一种可广泛推广的胫骨端固定方法 相似文献