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11.
Little is known about the immune status of different pig breeds and the role of dietary protein intake. The present study, performed on 96 barrows (48 pure-bred Bama mini-pigs (fatty genotype) and 48 Landrace pigs (lean genotype)) randomly assigned to two dietary treatment groups (low- or adequate protein diet), with twenty-four24 individuals per treatment), evaluated the levels of immunoglobulins and cytokines in serum, and intestinal and splenic innate immunity on the two breeds. Data showed significant interactions between breed and diet for adaptive and innate immunity. Throughout the experiment, Landrace pigs showed significantly higher intestinal immune responses than Bama mini-pigs, and an adequate provision of dietary protein improved the expression of specific antibodies in early growth phases. These finding have important implication for improving the immune status of Landrace pigs, which are a major source of protein for humans.

Abbreviations: BW: Body Weight; NRC diet: National Research Council diet; GB diet: Chinese conventional diet; CSFV: Classical Swine Fever Virus; IgG: Immunoglobulin G; IgM: Immunoglobulin M; SIgA: Secretory Immunoglobulin A.  相似文献   

12.
Background: Regeneration of lost periodontium in periodontitis is a challenge in that alveolar bone, cementum, and periodontal ligament need to be restored to their original architecture. Stem cells from exfoliated deciduous teeth (SHEDs) appear to be an attractive candidate for periodontium tissue regeneration. Previously, the authors successfully regenerated periodontal defects using autologous and allogeneic periodontal ligament stem cells (PDLSCs). The purpose of the present study is to investigate the ability of allogeneic SHEDs to regenerate lost periodontium in a swine periodontitis model. Methods: Animal models of periodontitis were established in miniature pigs, and allogeneic stem cells were isolated from miniature pig deciduous teeth (SPDs). The animal models were treated with SPDs plus hydroxyapatite/tricalcium phosphate (HA/TCP). Allogeneic PDLSCs plus HA/TCP or HA/TCP alone were set as positive control or control, respectively. Clinical assessments, computed tomography (CT) scanning, and histologic examination were used to evaluate the outcome of tissue regeneration. Results: Clinical indices including probing depth, gingival recession, and attachment loss showed significant restoration in the SPD and PDLSC treatment groups, compared to the HA/TCP group 12 weeks post‐transplantation. Meanwhile, CT scans showed that 75% of the samples had successful hard‐tissue regeneration in both PDLSC and SPD groups, compared to the HA/TCP group, where the success rate was only 25%. In addition, histologic examination demonstrated that SPD and PDLSC treatment brought about remarkable regeneration of periodontal tissues, whereas periodontal regeneration was rare in the HA/TCP group. Conclusions: Allogeneic SPDs can effectively repair hard and soft tissue loss brought about by periodontitis in a swine model. Allogeneic SHEDs, which are easily accessible, may be applied to treat periodontitis in clinics in the future.  相似文献   
13.

Introduction

The aim of this study was to evaluate pulpal responses after experimental direct pulp capping of mechanically exposed teeth with a new calcium silicate–based dentin replacement material.

Methods

Thirty-four anterior and posterior teeth of 3 miniature swine were used. Class V or I cavities were prepared on the buccal or occlusal surfaces, respectively. Pulpal exposures were further performed using a round carbide bur 0.8 mm in diameter. Exposures were treated with white MTA Angelus (Angelus, Londrina, PR, Brazil) or Biodentine (Septodont, Saint Maur des Fosses, France), and the cavities were further restored with Biodentine. The pulpal tissue responses were histologically assessed at postoperative periods of 3 and 8 weeks. Data were statistically analyzed using the Kruskal Wallis and the Mann-Whitney U tests.

Results

Inflammatory infiltration or pulp tissue necrosis was not found in any of the specimens. All teeth showed mineralized matrix formation in the form of a complete hard tissue bridge composed of osteodentin or osteodentin followed by a discontinuous or continuous reparative dentin zone. A significantly higher thickness of the hard tissue bridge was found in the group of teeth treated with Biodentine at both 3 and 8 weeks. A number of teeth, which were under root development at the onset of the experimental procedures, exhibited ectopic pulp calcification.

Conclusions

The application of both calcium silicate–based materials in direct contact with the mechanically exposed pulp of healthy miniature swine teeth led to pulp repair with complete hard tissue bridge formation. The thickness of hard tissue bridges was significantly higher after pulp capping with Biodentine.  相似文献   
14.
15.
Comparative Analysis of African Swine Fever Virus Genotypes and Serogroups   总被引:1,自引:0,他引:1  
African swine fever virus (ASFV) causes highly lethal hemorrhagic disease among pigs, and ASFV’s extreme antigenic diversity hinders vaccine development. We show that p72 ASFV phylogenetic analysis does not accurately define ASFV hemadsorption inhibition assay serogroups. Thus, conventional ASFV genotyping cannot discriminate between viruses of different virulence or predict efficacy of a specific ASFV vaccine.  相似文献   
16.
17.
Numerous hypotheses of temporal lobe epileptogenesis have been proposed, and several involve hippocampal mossy cells. Building on previous hypotheses we sought to test the possibility that after epileptogenic injuries surviving mossy cells develop into super‐connected seizure‐generating hub cells. If so, they might require more cellular machinery and consequently have larger somata, elongate their dendrites to receive more synaptic input, and display higher frequencies of miniature excitatory synaptic currents (mEPSCs). To test these possibilities pilocarpine‐treated mice were evaluated using GluR2‐immunocytochemistry, whole‐cell recording, and biocytin‐labeling. Epileptic pilocarpine‐treated mice displayed substantial loss of GluR2‐positive hilar neurons. Somata of surviving neurons were 1.4‐times larger than in controls. Biocytin‐labeled mossy cells also were larger in epileptic mice, but dendritic length per cell was not significantly different. The average frequency of mEPSCs of mossy cells recorded in the presence of tetrodotoxin and bicuculline was 3.2‐times higher in epileptic pilocarpine‐treated mice as compared to controls. Other parameters of mEPSCs were similar in both groups. Average input resistance of mossy cells in epileptic mice was reduced to 63% of controls, which is consistent with larger somata and would tend to make surviving mossy cells less excitable. Other intrinsic physiological characteristics examined were similar in both groups. Increased excitatory synaptic input is consistent with the hypothesis that surviving mossy cells develop into aberrantly super‐connected seizure‐generating hub cells, and soma hypertrophy is indirectly consistent with the possibility of axon sprouting. However, no obvious evidence of hyperexcitable intrinsic physiology was found. Furthermore, similar hypertrophy and hyper‐connectivity has been reported for other neuron types in the dentate gyrus, suggesting mossy cells are not unique in this regard. Thus, findings of the present study reveal epilepsy‐related changes in mossy cell anatomy and synaptic input but do not strongly support the hypothesis that mossy cells develop into seizure‐generating hub cells. © 2014 Wiley Periodicals, Inc.  相似文献   
18.
目的观察经球囊导管阻断肝动脉高热灌注生理盐水行肝段热凝固CT表现。方法实验猪6头,选用球囊导管阻断肝段动脉血流进行热灌注,导管流出温度设置50~60℃之间。热灌注结束后即刻、14天,行肝动脉DSA检查和肝脏螺旋CT扫描,14天将实验猪全部处死,取出肝脏进行病理检查。结果热灌注后14天,6头实验猪均存活。DSA检查见靶段动脉闭塞,肝组织热灌注区显示充盈缺损。肝脏热灌注区CT影像学表现:热灌注结束后即刻,热灌注区显示大片状低密度改变,无明显强化,边缘显示模糊;热灌注后14天,CT平扫示肝脏热灌注区呈典型楔形低密度改变;CT增强示热灌注区显示"三环征",由内向外分为低密度无增强区、边缘强化带和移行区透明带。病理上取得6个热凝固灶,CT上低密度无增强区、边缘强化带和移行区透明带分别代表病理的凝固性坏死区、炎性充血带和纤维化带。结论增强CT能准确反映经动脉导管肝段介入性热毁损的病理改变,DSA价值有限。  相似文献   
19.
《世界针灸杂志》2015,25(1):44-46
ObjectiveTo explore the effect of acupuncture at “J
ng Jiāj
” (
) on sudden hearing loss by observing the changes of the threshold of auditory brainstem response (ABR) of deaf guinea pigs.MethodsSixty healthy guinea pigs were selected, with computer randomization, 20 were randomly divided into a normal control group (group A), while the rest were randomly and equally divided into a model group (group B) and an acupuncture group (group C) when turned deaf after gentamycin sulfate and furosemide were administered. No treatment was administered for either the group A or the group B, while acupuncture at “J
ng Jiāj
” was given for the group C for 30 days. The ABR thresholds of each group were observed and recorded separately after the treatment for 15 days and 30 days.ResultsThe ABR threshold in the group C was lower than that in the group B after the treatment of 15 days (P<0.05). After the treatment of 30 days, the ABR threshold in the group C was obviously lower than that in the group B (P<0.01), and was obviously lower than that before acupuncture (P<0.01).ConclusionsAcupuncture at “J
ng Jiāj
” has definite effect on improving the hearing of deaf guinea pigs.  相似文献   
20.
To report the cochlear morphology and electrophysiology of Chinese experimental miniature pigs. Twenty Chinese experimental miniature pigs were used in this study. Auditory brainstem responses (ABR), cochlear endolymphatic potentials (EP), and the potassium concentrations of cochlear endolymph were recorded. Hair cell morphology was examined using electron microscopy. The capsule of cochlea of the miniature pig has three and one‐half turns which contains a 39‐mm long membranous labyrinth. The organ of Corti in the labyrinth encompasses three rows of outer hair cells and one row of inner hair cells. The stereocilia of the hair cells in the apical turn of the cochlea were significantly longer than those in the basal turn. The vestibular apparatus consists of three semicircular canals and the otolith organs. The average threshold of the ABR was 35–45 dB SPL (n = 20) from 4 to 32 kHz. There was no significant difference in the threshold or latency of the ABR between 1‐day‐old and 30‐day‐old miniature pigs. The average EP value was 77.3 ± 14 mV (n = 9) and the average potassium concentration was 147.1 ± 13 mM (n = 5) recorded from the second turn of the cochlea. These studies on the cochlear morphology and electrophysiology of the miniature pigs help to establish the Chinese experimental miniature pig as an animal model for future studies in otology and audiology. Anat Rec, 298:494–500, 2015. © 2014 Wiley Periodicals, Inc.  相似文献   
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