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1.
The objective of this study was to compare the implant longevity following two methods of peri-implant soft tissue optimization following free fibula flap (FFF): thinning of skin paddle (SP) and collagen matrix (CM). All patients who underwent rehabilitation with dental implants after mandibular reconstruction with FFF between June 2009 to May 2014 were retrospectively reviewed. Two methods of peri-implant soft tissue optimization were applied: (1) SP group, (2) CM group. Outcome measurements were: modified plaque index (mPI), modified sulcus bleeding index (mSBI), probing depth (PD), marginal bone loss (MBL), implant success rate and complication rates. A total of 24 patients with 69 implants were included in the study, with 8.7% (n = 6) of implants lost in 3 years. No statistically significant difference was found regarding the outcome measurements in both groups. Failed implants presented with statistically significant higher mPI, mSBI, PD and MBL scores during prosthesis delivery and subsequent follow-ups (P<0.03). In the SP group, one patient experienced SP necrosis which later underwent soft tissue optimization using CM. CM is an alternative peri-implant soft tissue, while thinning of SP is feasible if thickness is well controlled.  相似文献   
2.
Bacterial keratitis continues to be one of the leading causes of corneal blindness in the developed as well as the developing world, despite swift progress since the dawn of the “anti-biotic era”. Although, we have expeditiously developed our understanding about the different causative organisms and associated pathology leading to keratitis, extensive gaps in knowledge continue to dampen the efforts required for early and accurate diagnosis, and management in these patients, resulting in poor clinical outcomes. The ability of the causative bacteria to subdue the therapeutic challenge stems from their large genome encoding complex regulatory networks, variety of unique virulence factors, and rapid secretion of tissue damaging proteases and toxins.In this review article, we provide an overview of the established diagnostic techniques and therapeutics for keratitis caused by various bacteria. We extensively report the recent in-roads through novel tools for accurately diagnosing mono- and poly-bacterial corneal infections. Furthermore, we outline the recent progress by our groups and others in understanding the sub-cellular genomic changes that lead to antibiotic resistance in these organisms. Finally, we discuss in detail, the novel therapies and drug delivery systems in development for the efficacious management of bacterial keratitis.  相似文献   
3.
《Saudi Dental Journal》2022,34(5):385-389
PurposeThis work aimed to study the rate and quality of maturation of the mineral component of retained teeth 3.8, 4.8 and lower jaw fragment of a human in connective tissue dysplasia in different periods of postpartum ontogenesis.MethodsThe study involved 102 men (76 with connective tissue dysplasia and 26 without connective tissue dysplasia) divided into groups by age: 31–40, 41–50, 51–60 years. One tooth 3.8, 4.8 and a fragment of the alveolar part of the lower jaw in the projection of teeth 3.8, 4.8 0.5*0.5 cm in size were extracted from each examinee for medical indications.ResultsLow optical density values are observed at the age of 41–50 years, at the age of 51–60 years, indicating decreased mineral density and the presence of total areas of hypomineralization from the age 31–40 years in connective tissue dysplasia. At the age of 41–50, 51–60 years, at the boundary of connective tissue structures and periosteum, a pronounced sclerosis and deformation of delineation elements were observed; at the age of 31–40 years, the indicated changes were less pronounced. At the age of 31–40 years, the level of bone plate dissection has a local character, after 40 years, it has a generalized character.ConclusionProgressive osteoporosis of the mandible and incomplete amelogenesis are an obstacle to the correct and harmonious teething of the lower wisdom teeth after the age of 30.  相似文献   
4.
Caveolin-1 (Cav-1) appears to be both a pathophysiological contributor and a target in different inflammatory and hyperproliferative skin conditions as well as in skin aging. Skin fibroblasts demonstrate an up-regulation of Cav-1 expression both in chronological and UV-induced aging, and such an up-regulation was observed both in vitro and in vivo. Typical alterations in aging skin involve a reduction of the dermis thickness, a significant expansion of the dermal white adipose tissue as well as modifications of the content and distribution of hyaluronan, impairment of autophagic flux, a reduction of collagen expression and an increase in tissue inflammation. All of these phenomena can be connected with changes in Cav-1 expression in the aging skin. Modified expression of Cav-1 can also significantly influence the mechanical properties of individual skin layers, thus changing the total mechanical stability of the layered composite skin/WAT, leading to typical structural modifications of the skin surface in the aging skin. Selective reduction of Cav-1 expression has the potential to exert anti-aging effects on the skin.  相似文献   
5.
《Journal of endodontics》2020,46(12):1876-1883
Streptococcus mutans plays an important role in caries etiology and eventually in systemic infections. However, it is often found in infected root canals, but the pathophysiological characteristics of strains residing in this site are largely unknown. Here, we characterized strains of S. mutans isolated from root canals of primary (PI) and secondary/persistent (SI) endodontic infections in relation to serotype and genotype; presence of genes coding for collagen binding proteins (CBPs); collagen binding activity and biofilm formation capacity; ability to withstand environmental stresses; systemic virulence in Galleria mellonella; and invasion of human coronary artery endothelial cells and human dental pupal fibroblasts. Samples from 10 patients with PI and 10 patients with SI were collected, and a total of 14 S. mutans isolates, belonging to 3 genotypes, were obtained. Of these, 13 were serotype c, and 1 was serotype k. When compared with the reference strains, the clinical isolates were hypersensitive to hydrogen peroxide. Remarkably, all 14 strains harbored and expressed the CBP-encoding gene cbm, showing increased binding to collagen, enhanced systemic virulence in G. mellonella, and ability to invade human coronary artery endothelial cells and human dental pupal fibroblasts when compared with CBP-negative strains. Whole genome sequence analysis of PI and SI isolates revealed that these strains are phylogenetically related but genetically distinct from each other. Our findings highlight the importance of CBPs in facilitating colonization and persistence of S. mutans in collagenous substrates such as root canals and their potential role in the pathogenesis of endodontic infections.  相似文献   
6.
BackgroundMinimally-invasive methods to treat scars address a common pathway of altering collagen structure, leading to collagen remodeling.ObjectiveIn this study, we employed in situ redox chemistry to create focal pH gradients in skin, altering dermal collagen, in a process we refer to as electrochemical therapy (ECT). The effects of ECT to induce biochemical and structural changes in ex vivo porcine skin were examined.MethodsDuring ECT, two platinum electrodes were inserted into fresh porcine skin, and following saline injection, an electrical potential was applied. pH mapping, high frequency ultrasonography, and two photon excitation microscopy and second harmonic generation (SHG) microscopy were used to evaluate treatment effects. Findings were correlated with histology.ResultsFollowing ECT, pH mapping depicted acid and base production at anode and cathode sites respectively, with increasing voltage and application time. Gas formation during ECT was observed with ultrasonography. Anode sites showed significant loss of SHG signal, while cathode sites showed disorganized collagen structure with fewer fibrils emitting an attainable signal. Histologically, collagen denaturation at both sites was confirmed.ConclusionWe demonstrated the production of in situ acid and base in skin occurring via ECT. The effects chemically and precisely alter collagen structure through denaturation, giving insight on the potential of ECT as a simple, low-cost, and minimally-invasive means to remodel skin and treat scars.  相似文献   
7.
目的探讨补骨脂素抗增生性瘢痕的作用机制。方法体外培养成纤维细胞,按随机数字表法分为正常组(培养正常成纤维细胞)、瘢痕组(培养增生性瘢痕成纤维细胞)、TGF-β1组(10 ng/ml TGF-β1处理增生性瘢痕成纤维细胞5 min^12 h)、Smurf2 RNA干扰组[Smad泛素化调节因子2(Smad ubiquitin regulatory factor2,Smurf2)siRNA转染增生性瘢痕成纤维细胞72 h]、补骨脂素组(10μmol/L补骨脂素处理增生性瘢痕成纤维细胞继续培养72 h)、补骨脂素+TGF-β1组(增生性瘢痕成纤维细胞加入补骨脂素培养72 h后加入TGF-β1培养6 h)。采用Western blot法检测Smurf2、α-平滑肌肌动蛋白(α-actin SMA,α-SMA)蛋白表达;RT-PCR法检测Ⅰ型胶原蛋白mRNA表达;ELISA法检测TGF-β1蛋白分泌。结果与正常组比较,瘢痕组Smurf2蛋白[(0.83±0.08)比(0.38±0.07)]表达增加(P<0.05);与瘢痕组比较,Smurf2 RNA干扰组TGF-β1[(2.2±0.18)比(4.2±0.47)]表达降低(P<0.05);TGF-β1组Smurf2[(0.71±0.06)比(0.42±0.04)]、α-SMA[(1.42±0.12)比(0.91±0.09)]蛋白表达增加(P<0.05),Ⅰ型胶原蛋白mRNA[(0.72±0.09)比(0.41±0.07)]表达增加(P<0.05);补骨脂素组Smurf2[(0.05±0.01)比(0.42±0.04)]、α-SMA[(0.71±0.07)比(0.91±0.09)]蛋白表达降低(P<0.05),Ⅰ型胶原蛋白mRNA表达[(0.12±0.04)比(0.41±0.07)]降低(P<0.05)。结论补骨脂素可能通过TGF-β1/Smurf2信号通路抑制α-SMA蛋白表达,从而降低Ⅰ型胶原蛋白表达,起到抑制瘢痕形成的作用。  相似文献   
8.
Mostly, collagen is obtained from mammalian sources, but its use is limited because of high cost and various allergic reactions. In this review, different alternative sources of collagen were explored and methods for isolation and peptide generations are summarized. Bioactive peptides are short sequences of 2–20 amino acid residues with positive effect on human health. This review summarizes various biological activities of sea food derived peptides/hydrolysates includes antioxidant, inflammatory, antifreeze, angiotension-I converting enzyme (ACE-I) inhibition, antimicrobial, antiaging, wound healing and anticoagulant activities. Moreover, this review also highlights the therapeutic potential and importance of sea-food derived peptides in various pharmaceutical, biomedical, food and cosmetic industries. This review also proposes biological solution for utilization of seafood derived waste in the development of collagen-based food ingredients that is otherwise cause environmental pollution.  相似文献   
9.
10.
目的:观察长期高脂饮食对小鼠皮肤创面愈合的影响并初步探讨其相关机制。方法10周龄C57BL/6J 野生型小鼠16只,随机分为2组,每组8只,分别采用高脂及普通膳食喂养8周后,在小鼠背部建立全层皮肤缺损模型。每日对创面愈合状况进行观察,记录创面愈合率及上皮化水平。于术后第14天处死所有小鼠并切取创面组织进行组织学检测,比较两组创面新生表皮厚度、创面床内胶原沉积率、新生血管数目、细胞增殖及炎症细胞浸润水平。喂养前、喂养8周后及手术后第14天检测体重。术后第14天禁食12 h 后检测外周血总胆固醇(TC)、三酰甘油(TG)水平。采用 t 检验进行统计学分析。结果高脂膳食组在高脂喂养8周后及手术后第14天平均体重[分别为(27.3±0.7)g 和(28.8±0.7)g]显著高于普通膳食组[分别为(21.2±0.6)g 和(23.1±1.1)g],两组比较,t 值分别为21.98和25.22,均 P <0.001。术后第14天,高脂膳食组 TG 及 TC 水平[分别为(1.35±0.32)mmol/L 和(4.21±0.41)mmol/L]远高于普通膳食组[分别为(0.99±0.28)mmol/L 和(2.71±0.31)mmol/L,两组比较,t 值分别为2.24和6.49,均 P <0.05];高脂膳食组创面愈合时间明显慢于普通膳食组[分别为(13.5±0.5)d 和(12.6±1.1)d,t =1.99,P <0.05],创面新生表皮薄于普通膳食组[分别为(47.8±13.8)μm 和(95.7±13.7)μm,t =5.68,P <0.001],CD31阳性血管数低于普通膳食组[分别为(8±1)个和(13±3)个, t =4.1,P <0.001],ki-67阳性细胞数目低于普通膳食组[分别为(21±4)个和(49±10)个,t =3.33,P <0.001],但巨噬细胞及肥大细胞浸润水平明显高于普通膳食组(均 P <0.05),各组创面床内胶原沉积率差异无统计学意义(P >0.05)。结论长期高脂饮食会影响小鼠创面的愈合,延缓皮肤创面修复。  相似文献   
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