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81.
目的探讨口服抗原对巨噬细胞(M)共刺激分子CD80/CD86表达的影响及其在诱导妊娠免疫耐受中的作用。方法自然流产小鼠(CBA/J×DBA/2)分为免疫组和未免疫组,免疫组分别口服滋养细胞膜抗原(TMA2)和卵清蛋白(OVA),以正常妊娠小鼠(CBA/J×BALB/c)作为对照组。采用双标记流式细胞分析技术,分别检测各组小鼠脾脏及肠系膜淋巴结(MLN)CD80 M和CD86 M的表达。结果MLN内,未免疫组CD80 M表达明显高于对照组(P<0.05),而CD86 M含量明显低于对照组(P<0.001);TMA2免疫组CD80 M含量明显低于未免疫组(P<0.05);OVA免疫组CD86 M含量明显高于未免疫组(P<0.001)。脾脏内,CD80 M表达在各组间比较无显著差异;CD86M表达,未免疫组明显低于对照组(P<0.05),TMA2免疫组显著低于未免疫组(P<0.05),OVA免疫组则显著高于未免疫组(P<0.001)。结论流产的发生与M表面共刺激信号CD80/CD86异常有关;口服适当抗原可改变CD80/CD86 M表达模式,诱导妊娠免疫耐受的形成。  相似文献   
82.
Background With the development of genetically modified crop plants there has been a growing interest in the approaches available to assess the potential allergenicity of novel gene products. For additional assessment of the potential allergenicity of expressed proteins, informative data can be generated using animal models. Soybean is one of the major source of protein in human and animal nutrition, and has also been well characterized as a major allergenic source. Advances in biotechnology have resulted in an increasing number of genetically engineered foods, and among these soybean is one of the most widespread. Objective To develop and characterize a murine model of IgE‐mediated soybean sensitization induced by intragastric immunization, in the presence of Cholera Toxin, with wild‐type soybean extract (wt‐SE) or with genetically modified soybean extract (gm‐SE). Methods Balb/c mice born in our animal facilities, from females fed on soy‐free food, were fed with the same soy‐free food and used in all the experiments. Mice were sensitized by gavages with soybean extracts, and allergen‐specific IgE and IgG responses were studied by direct ELISA and ELISA inhibition. Antigen‐specific cell proliferation and cytokine production were evaluated in spleen cell cultures. Results Sensitization with both soybean extracts induced high levels of antigen‐specific IgE and IgG1 and low levels of specific IgG2a. Both wt‐SE and gm‐SE were able to inhibit the binding of specific IgE from mice immunized with gm‐SE to the same antigen used for the ELISA coating. A comparable proliferative response was obtained with the homologous as well as with the heterologous extracts. Conclusion In sensitized mice, we observed a predominantly T‐helper type 2 (Th2)‐type immune response, with increased soybean‐specific IgE and IgG1 antibodies and a concomitant increase of IL‐4 and IL‐5 production. Results obtained by specific IgE ELISA inhibition and by antigen‐specific T cell proliferation demonstrated that wt‐SE and gm‐SE shared B and T epitopes. The present murine model of soybean sensitization established by the oral route should provide valuable information about risk assessment for food allergy from new proteins of genetically modified foods.  相似文献   
83.
目的:评价口服水剂、水灌肠及两者联合应用充盈肠道后,使用MSCT显示成人正常肠道的能力。材料和方法:将43名非肠道病变志愿者分别采用口服水剂法(21例)、水灌肠法(12例)、双重法(口服水剂和水灌肠联合应用,10例)充盈肠道,然后行MSCT平扫和增强扫描并进行图像重建,对小肠和大肠各肠段充盈状态进行评价。结果:口服水剂法回肠充盈良好,水灌肠法大肠充盈良好,双重法回肠及大肠均充盈良好。口服水剂法小肠充盈优于水灌肠法,与双重法无显著差异,大肠充盈状态水灌肠法明显优于口服水剂法,与双重法无显著差异。结论:口服水剂和水灌肠联合应用可以在MSCT同时较好地充盈显示小肠和大肠,而两种方法单独使用则仅能分别充盈显示小肠和大肠,需要根据显示目的选择相应的充盈方法。  相似文献   
84.
刘红刚  郑麟蕃 《中华医学杂志》1994,74(2):92-93,T011
用Warthin-Starry螺旋体特殊染色法及透射电镜观察,分别在19例肉芽肿性唇炎和5例梅罗综合征(MRS)病人的病变组织内发现有螺旋体存在,并对其在光,电镜下的形态和在病变组织内的分布部位进行了描述。经用大刘量青霉素治疗11例病人,10例有效。本结果为MRS的发可能和螺旋体感染有关的推测提供了依据。  相似文献   
85.
Background Nowadays, liver resection is a routine operative procedure in surgical centers, and strategies must be aimed at avoiding additional risk factors. Extrahepatic isolation of portal vein, hepatic artery and hepatic duct, as well as lymphadenectomy of the liver hilum are generally accepted steps of liver resection, even for metastatic and benign indications. Our primary aim was to analyze the feasibility, blood loss, blood transfusion requirements, incidence of complications, and outcome using the approach for intrahepatic devascularization leaving the extrahepatic hilus untouched. Materials and methods Thirty-eight consecutive patients with resection for metastases and benign liver tumors were selected. After hilar examination, the extrahepatic structures remain intact, and during parenchyma dissection, the whole right or left or the appropriate bi-segmental pedicle is isolated intrahepatically and then transected using a stapler device. Results The used technique was feasible in all cases, and no intra- or postoperative surgical complications were observed. To date, no tumor recurrence was found in the hilum during the follow-up period. Conclusion The intrahepatic pedicle stapling technique appears to be feasible and safe in liver resection. Hilar dissection can, thus, be avoided in liver metastasis and benign liver tumors.  相似文献   
86.
BACKGROUND: Food allergies are an important cause of life-threatening hypersensitivity reactions. Oral tolerance can be considered the default immune response to dietary antigens, with immune deviation resulting in allergic sensitization. However, primary sensitization to food allergens may not solely be through the gastrointestinal mucosa, as strong T-helper type 2 (Th2)-biased immunity can result from exposure to protein allergens on barrier-disrupted skin. OBJECTIVE: The purpose of this study was to examine whether exposure to allergens through the skin may interfere with the normal development of oral tolerance and promote allergic sensitization to food proteins. METHODS: Female BALB/c mice were exposed epicutaneously to peanut protein and induction of systemic oral tolerance through high dose feeds of peanut protein was subsequently assessed. Other mice were rendered tolerant prior to epicutaneous peanut exposure. Sensitivity to peanut was determined by assessing delayed-type hypersensitivity, proliferative, cytokine and antibody responses. RESULTS: Epicutaneous exposure to peanut protein induced potent Th2-type immunity with high levels of IL-4 and serum IgE. Primary skin exposure prevented the subsequent induction of oral tolerance to peanut in an antigen-specific manner. Upon oral challenge, mice became further sensitized and developed strong peanut-specific IL-4 and IgE responses. Furthermore, animals with existing tolerance to peanut were partly sensitized following epicutaneous exposure. CONCLUSION: Epicutaneous exposure to peanut protein can prevent induction of oral tolerance, and may even modify existing tolerance to peanut. Epidermal exposure to protein allergens selectively drives Th2-type responses, and as such may promote sensitization to food proteins upon gastrointestinal exposure.  相似文献   
87.
口腔门诊治疗并发晕厥106例回顾分析   总被引:2,自引:0,他引:2  
目的:通过对1983年以来,孝感市中心医院口腔中心门诊治疗并发晕厥106例的回顾性分析,探讨口腔门诊治疗并发单纯性晕厥的原因及一些相关因素,增强医患双方的防治意识,安全顺利的进行口腔门诊治疗。方法:对106例单纯性晕厥反应,采取现场询问式调查的方法,对其一般情况,口腔门诊治疗经历,治疗时的心态,口腔门诊治疗的了解,以及不同口腔治疗晕厥发生情况等进行调查、归纳、分析。结果:1)晕厥的发生与患者的年龄有关,12~40岁口腔门诊治疗经历欠缺的患者是口腔门诊治疗并发晕厥的高危人群。2)口腔患者进行治疗前心理准备充足与否对并发晕厥反应的影响较大。3)晕厥在口腔门诊某些治疗中发生率较高,拔牙术最多,其次为脓肿切排。86%(92例)属因畏惧疼痛导致紧张而诱发的血管抑制性晕厥。4)晕厥多发生于治疗初期(93:13)。结论:口腔门诊治疗并发晕厥临床表现多不严重,但对患者就诊和医师的治疗影响明显,切实做好口腔治疗错误信息,消除和减轻他们的疑虑和畏惧的紧张心情,对保障口腔门诊治疗安全尤为重要。  相似文献   
88.
Selected media were compared for primary isolation and detection of oral treponemes from clinical samples. Forty-eight subgingival plaque samples from 45 patients suffering from periodontitis were anaerobically cultivated for 2 weeks at 37°C. Of the 9 media studied, Medium 10 (M10), which was supplemented with 10% rabbit serum and incubated using the plate-in-bottle method, supported the highest colony-forming units of the anaerobes. The treponemal colonies were detected at least on one medium from 83% of the subgingival plaque samples. The new oral spirochete medium in an anaerobic chamber supported the highest detection frequency of the oral treponemes (64% of samples); however, M10 in the plate-in-bottle was found to produce the highest colony-forming unit recovery of the oral treponemes (median 3.6% of the total colony-forming units). This study suggests that M10 in the plate-in-bottle and new oral spirochete medium in the anaerobic chamber are essential in cultivating oral treponemes.  相似文献   
89.
Long-term oral anticoagulation requires careful patient monitoring in order to optimize results and to limit hemorrhagic or thromboembolic complications of treatment. For this reason, any improvement in anticoagulant control and management can be expected to have far-reaching consequences in extending longevity and decreasing complications in anticoagulated patients after heart valve surgery. Because one attractive means of improving anticoagulant management is to give patients a share of the responsibility, a program was designed to encourage patients to take an active role in monitoring their own prothrombin time (PT) and managing their own oral anticoagulation. During the period from August 1986 to February 1992, 600 patients requiring long-term anticoagulation, mainly after heart valve replacement, were trained to measure their own PT at the Cardiac Rehabilitation Center (Herz-Krauslauf-Klinik, Bad Berleburg, Germany) and to manage their own therapy: 216 patients could be followed with regard to their self-determined prothrombin times. The results were within the target range in 83.1% of the PT determinations (n=12,306 measurements) taken by the patients themselves. Neither major bleeding nor thromboembolic complications were observed in 205 patient-years of self-monitoring of PT and self-management of oral anticoagulation.  相似文献   
90.
The aim of this prospective study was to characterize an implant patient population exhibiting clinical signs of peri‐implantitis and to determine subsequently the incidence of progressive attachment loss. The predictive values of diagnostic parameters were evaluated. 25 patients with 54 endosseous implants that had been loaded for 41±15 months were included in the study. Clinical parameters included the assessment of plaque, bleeding on probing, probing depth, attachment levels, and Periotest® values. Probing measurements were performed in duplicate by means of a controlled force electronic probe (Periprobem). Peri‐implant crevicular fluid samples were collected and assayed for neutral proteolytic enzyme (NPE) activity (Periocheck®). Analysis of duplicate baseline probing data revealed a high degree of reproducibility (mean difference: 0.1±0.3mm). A minimum threshold of 1.0mm (>3×S.D.) loss of probing attachment was chosen to classify a site as positive for breakdown. Alternatively, the tolerance method was employed to identify sites with progressive attachment loss. After 6 months, irrespective of the analytical method, 6 percent of all sites (in 19% of the implants) and 28% of the patients had experienced further per attachment loss. There were significant differences ( p <0.05) in mean plaque (73% vs. 45%) and NPE (36% vs. 12%) scores between patients with progressive peri‐implantitis and those with stable peri‐implant conditions. Both bleeding on probing and the NPE‐test were characterized by high negative predictive values, and thus negative scores can serve as indicators for stable peri‐implant conditions. For monitoring peri‐implant health during recall visits, attachment level recordings with a controlled force electronic probe in conjunction with enzymatic diagnostic tests of the host response can be recommended.  相似文献   
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