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排序方式: 共有832条查询结果,搜索用时 15 毫秒
1.
The Distally Based Sural Artery Flap for Ankle and Foot Coverage   总被引:1,自引:0,他引:1  
The sural artery flap is a distally based fasciocutaneous flap that has many advantages to offer for coverage in the foot and ankle area. It has the largest arc of rotation of all the regional flaps and does not require sacrifice of any major artery, and moderate-to-large-sized defects can be covered adequately. The dissection technique is simple, and donor site morbidity is minimal. We report our experience with 17 cases. Age range was from 13 to 56 years. Ten (59%) defects were posttraumatic, 3 (17%) were related to reconstructive surgery of the foot or tendon Achilles', 2 (11%) resulted from tumor resection, and 1 each were from infection and gunshot wound. The smallest flap was 6 x 4 cm and the largest was 15 x 12 cm, with the average size being 11 x 7.5 cm. In 5 cases, the donor site was closed primarily, and in other cases, split-thickness skin graft was needed. The short saphenous vein was included in the pedicle in all cases. There was no incidence of complete flap necrosis. Follow-up ranged from 3 to 30 months. Two cases (12%) developed partial superficial necrosis. In 1 case, there was partial wound dehiscence that needed debridement and repair. Another case had postoperative discharge, which subsided after removal of the calcaneal plate. None of the patients complained of any functional problem related to loss of sensation along the lateral border of the foot. The sural island flap is a reliable, safe, and easy method of providing soft tissue coverage in the area of the foot and ankle.  相似文献   
2.
BACKGROUND: Intranasal corticosteroids are recommended as first-line therapy for the treatment of allergic rhinitis. Fluticasone furoate is a novel enhanced-affinity glucocorticoid for the treatment of allergic rhinitis. OBJECTIVE: To compare the efficacy and safety of intranasal fluticasone furoate with those of vehicle placebo nasal spray in adult and adolescent patients with perennial allergic rhinitis (PAR). METHODS: After screening (7-14 days), patients 12 years and older with confirmed PAR were randomized to receive fluticasone furoate, 110 microg once daily, or placebo once daily intranasally for 4 weeks in this double-blind, multicenter study. The primary end point was mean change from baseline during the entire treatment period in daily reflective total nasal symptom score (rTNSS), recorded on diary cards by patients, using a 4-point categorical scale. RESULTS: The mean reduction from baseline during the treatment period in daily rTNSS was significantly greater in fluticasone furoate recipients than in placebo recipients (P = .005). This finding was supported by significantly greater mean reductions in morning rTNSS and evening rTNSS (P = .004 and P = .011, respectively). A significantly greater mean reduction in instantaneous morning predose TNSS with fluticasone furoate compared with placebo (P = .006) confirmed the efficacy of once-daily administration. Fluticasone furoate was also significantly more effective than placebo in overall response to therapy (P = .005). CONCLUSIONS: Fluticasone furoate nasal spray, 110 microg once daily, effectively relieved nasal symptoms of PAR in adults and adolescents 12 years and older.  相似文献   
3.
Photosensitive benzocyclobutene (photo-BCB) is a class of polymers with the trade name Cyclotene. The photoimagable property of Cyclotene makes it suitable for the manufacture of microelectronic devices. The motivation behind this study is that we see an exciting application of photo-BCB as substrates in implantable microelectronic biomedical devices due to several desirable properties distinctive from other polymer materials. To our knowledge, however, photo-BCB has never been tested for biomedical implant applications, as evidenced by the lack reported data on its biocompatibility. This study takes the first step towards assessing photo-BCB biocompatibility by evaluating the cytotoxicity and cell adhesion behavior of Cyclotene 4026 coatings exposed to monolayers of glial and fibroblast cells in vitro. It can be concluded from these studies that photo-BCB films deposited on silicon wafers using microfabrication processes did not adversely affect 3T3 fibroblast and T98-G glial cell function in vitro. We also successfully rendered photo-BCB films non-adhesive (no significant fibroblast or glial cell adhesion) with surface immobilized dextran using methods developed for other biomaterials and applications. Future work will further develop prototype photo-BCB microelectrode devices for chronic neural implant applications.  相似文献   
4.
Decorin is a small proteoglycan that binds to transforming growth factor-beta (TGF-beta) and inhibits its activity. However, its interaction with platelet-derived growth factor (PDGF), involved in arterial repair after injury, is not well characterized. The objectives of this study were to assess decorin-PDGF and decorin-PDGF receptor (PDGFR) interactions, the in vitro effects of decorin on PDGF-stimulated smooth muscle cell (SMC) functions and the in vivo effects of decorin overexpression on arterial repair in a rabbit carotid balloon-injury model. Decorin binding to PDGF was demonstrated by solid-phase binding and affinity cross-linking assays. Decorin potently inhibited PDGF-stimulated PDGFR phosphorylation. Pretreatment of rabbit aortic SMC with decorin significantly inhibited PDGF-stimulated cell migration, proliferation, and collagen synthesis. Decorin overexpression by adenoviral-mediated gene transfection in balloon-injured carotid arteries significantly decreased intimal cross-sectional area and collagen content by approximately 50% at 10 weeks compared to beta-galactosidase-transfected or balloon-injured, non-transfected controls. This study shows that decorin binds to PDGF and inhibits its stimulatory activity on SMCs by preventing PDGFR phosphorylation. Decorin overexpression reduces intimal hyperplasia and collagen content after arterial injury. Decorin may be an effective therapy for the prevention of intimal hyperplasia after balloon angioplasty.  相似文献   
5.
The purpose of this double-blind, placebo-controlled study was to determine and compare the clinical efficacy and tolerance of human leukocyte -interferon (incorporated 2 × 106 IU/g) in hydrophilic cream to cure genital warts. Preselected Asian female patients (n=150) aged 18–40 years (mean 22.5), with the clinical and biopsy-confirmed diagnosis of genital warts (mean 2.64), predominantly flat vaginal condylomas, were randomly allocated to 3 parallel groups. Each patient was given a coded tube containing 80 g placebo/active preparation with a graduated applicator. Patients were instructed to inject 6 g of the either alloted placebo/active cream deep into the vagina thrice a day for 3 consecutive days (group A) or 4 consecutive days (group B) per week, and if not cured the same treatment was extended to 3 more weeks (maximum 4 weeks active treatment). To assess the clinical efficacy patients were examined on a week-to-week basis. A total clearance of warts (biopsy-confirmed) was evaluated as a complete cure. Patients cured during the treatment were spared further treatment and were requested to visit us after 16 weeks for relapse control. As for the remaining patients, empty tubes were collected, and similarly coded replacement tubes were given for further treatment (in total 588 tubes were used). By the end of the treatment 57.2% lesions (227/397) were eliminated in all the groups: 48% patients in group A, 90% patients in group B, and 10% patients in placebo groups taken as completely cured. Of the 150 patients 128 (85.3%) did not complain of any drug-related adverse symptoms. Transitory increase in body temperature (mean 38.4°C), accompanied by headache (14.6%) and generalized itching (6.6%) were the most frequently reported side effects; however, treatment was well tolerated by all the patients, and there were no dropouts. Our findings indicate that clinical efficacy is dose dependent, that is, the results of group B were significantly superior to that of group A (P < 0.05). Of the 49.3% cured patients (74/150) followed up for 6 months (monthly basis) seven had a relapse, and none had reinfection. It is concluded that clinical efficacy of leukocyte interferon-a to cure genital warts is dose dependent. These results further support the view that leukocyte interferon-a incorporated in hydrophilic cream can be considered a reliable, safe, and home-based treatment to cure vulvar and vaginal warts.Abbreviation HPV human papillomavirus  相似文献   
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7.
背景:近几年国外学者在脊髓损伤的病理机制、损伤后神经元的保护、少突胶质细胞的再生及神经干细胞的移植治疗等研究方面取得了实质性地进展。介绍国外近10年来对脊髓损伤的新认识,最新研究成果及未来的科研和治疗方向。资料来源:应6用计算机检索Medline数据库1987-01/2006-10脊髓损伤的相关文章,限定文章语言种类为English,检索词为“脊髓损伤;神经干细胞;轴突;神经营养因子;动物模型”,进行不同组合,选出相关文章。资料选择:对资料进行初审,选择脊髓研究中的与神经干细胞及神经营养因子有关的研究文献查找全文。纳入标准:①脊髓损伤中以探讨其机制及新治疗方法的文章。②探讨脊髓损伤后轴突再生,生长锥作用,引导再生方向的靶点,突触再形成及功能重建的文章。③神经营养因子和内源性神经干细胞治疗的文章。排除标准:①未被SCI收录的文章,相类似的研究。②无英文摘要的文章。资料提炼:共收集到相关文献1166篇,按上述标准纳入101篇,实际采用61篇,脊髓损伤机制相关文献12篇,轴突再生相关文献14篇,增长锥作用相关文献8篇,少突胶质细胞相关文献8篇,神经干细胞相关文献7篇,神经生长因子相关文献12篇。其余文献均被排除。资料综合:①脊髓损伤功能恢复的基础:损伤的轴突再生及增长;轴突穿透损伤瘢痕区的能力;轴突朝着正确的靶区方向再生;轴突增长到一定程度后停止,终端形成突触,与神经元相接;神经传递功能重建及运动功能重新恢复。②脊髓损伤的神经病理分析:脊髓损伤后的原发性损害、继发性损害。③脊髓损伤的分子生物学机制包括3个方面:对于成年人中枢神经系统损伤后的神经元的发展、再生,神经元通路的建立起着重要的作用轴突增长锥;对轴突的再生起到抑制作用中枢神经系统髓鞘蛋白;细胞膜和细胞内信号传递。④脊髓损伤中起重要作用的细胞和因子:少突胶质细胞,白血病抑制因子和Minocycline,内源性神经干细胞。⑤脊髓损伤动物模型:最常使用的模型是全部离断、部分离断模型和挫伤模型。⑥脊髓损伤研究的前景:已经开始把动物实验中神经营养因子和神经干细胞治疗发现用于临床,如白血病抑制因子在国外已经开始临床Ⅳ期实验,对内源性神经干细胞的诱导调控增殖研究也已经越来越受到重视。结论:神经营养因子干预治疗及神经干细胞治疗使脊髓损伤后的功能恢复成为可能。进一步探讨神经营养因子引起轴突再生的机制,将是脊髓损伤研究领域的未来方向,了解引导调控神经干细胞的增殖和分化方向,将在修复脊髓损伤方面发挥巨大的作用。  相似文献   
8.
Background: Although it is well recognized that recovery of pulmonary vein (PV) conduction is common among patients who fail atrial fibrillation (AF) ablation, little is known about the precise time course of recurrence.
Objective: To determine the incidence and time course of early recurrence of conduction after PV isolation during AF ablation.
Methods: The patient population was composed of 14 consecutive patients (9 men [64%]; age 56 ± 7 years) with AF who underwent radiofrequency catheter ablation via circumferential ablation with PV isolation, determined by a circular mapping catheter. After successful isolation of the PVs, repeat circular electrode recordings from each PV were obtained at 30 and 60 minutes.
Results: After complete isolation of all PVs, early PV recurrence was observed in 13 (93%) patients and 26 veins (50%). Seventeen veins (33%) showed a first recurrence at 30 minutes, while nine veins (17%) showed a first recurrence at 60 minutes.
Conclusion: The results reveal an extremely high rate of early recurrence of PV conduction following AF ablation. It is particularly notable that about one-fifth of the veins remained isolated at 30 minutes, but subsequently developed recurrence between 30 and 60 minutes. Of the veins that showed early recurrence, one-third developed a first recurrence at 60 minutes. These findings suggest that AF ablation procedures should incorporate a 60-minute waiting period after initial isolation in order to detect early recurrence of conduction.  相似文献   
9.
Interpenetrating polymer networks (IPNs) of poly (acrylamide-co-ethylene glycol/acrylic acid) functionalized with an -Arg-Gly-Asp- (RGD) containing 15 amino acid peptides, derived from rat bone sialoprotein (bsp-RGD(15), were grafted to titanium implants in an effort to modulate bone formation in the peri-implant region in the rat femoral ablation model. Bone-implant contact (BIC) and bone formation within the medullary canal were determined using microcomputed tomography at 2 and 4 weeks postimplantation. BIC for bsp-RGD(15)-IPN implants was enhanced relative to hydroxyapatite tricalcium phosphate (HA-TCP) coated implants, but was similar to all other groups. Aggregate bone formation neither indicated a dose-dependent effect of bsp-RGD(15) nor a meaningful trend. Mechanical testing of implant fixation revealed that only the HA-TCP coated implants supported significant (>1 MPa) interfacial shear strength, despite exhibiting lower overall BIC, an indication that bone ingrowth into the rougher coating was the primary mode of implant fixation. While no evidence was found to support the hypothesis that bsp-RGD(15)-modified IPN coated implants significantly impacted bone-implant bonding, these results point to the lack of correlation between in vitro studies employing primary osteoblasts and in vivo wound healing in the peri-implant region.  相似文献   
10.
Intraluminal filling defects are occasionally encountered on coronary angiography and often related with coronary thrombi. However, other conditions affecting the coronary arteries may present with similar angiographic findings causing diagnostic uncertainty. Accurate characterization of the angiographic filling defect is critical, particularly in patients planned for a percutaneous coronary intervention (PCI), as diagnosis of a coronary thrombus not only increases the risk of post procedural adverse events but also requires a specific therapeutic approach. In this paper, we report three patients in whom coronary angiography revealed intraluminal filling defects mimicking coronary thrombi. When further investigated with intravascular ultrasound (IVUS) as a part of the planned PCI, the thrombus was excluded and alternate etiology of the filling defect was confirmed in all patients. The angiographic "pseudothrombi" were produced by coronary dissection in one and by heavy calcification within the atherosclerotic plaque in two patients. The use of IVUS allowed accurate characterization of the angiographic filling defect and provided important information to guide management and optimize therapeutic approach.  相似文献   
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