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51.
BACKGROUND: Acyclovir (ACY) is a useful therapeutic agent for the systemic treatment of herpes virus infection. An increase in urinary phosphate excretion and polyuria has been described. The objective of this study was to analyze the exact mechanism of the urinary-concentrating dysfunction and the increase in phosphaturia associated with ACY. METHODS: We first analyzed 7 (adult and pediatric) non-AIDS cases of encephalitis receiving 15 mg/kg bw/d of intravenous ACY. Fractional phosphate and sodium excretion, urinary potassium volume, and plasma phosphate concentrations were analyzed. Additional studies in rats treated with intraperitoneal ACY (100 mg/kg bw) were also conducted. Animals were maintained in metabolic cages and 24-hour urine samples were collected to measure volume, osmolality, and sodium/potassium/phosphate excretion. Treated rats were also evaluated after 24 hours and 48 hours of water deprivation. Northern hybridization and semiquantitative immunoblotting were performed to evaluate (in both control and treated animals) expression of the cotransporters Na-Pi type IIa (Na-Pi-IIa) and Na-K-2Cl (NKCC2). Semiquantitative immunoblotting was carried out in the kidneys of ACY rats and control rats in order to analyze aquaporin 2 (AQP2) protein expression. RESULTS: Patients started on ACY developed polyuria and hyperphosphatemia after 48 hours. In rats, ACY-induced hyperphosphaturia and hypophosphatemia were accompanied by increased excretion of sodium, potassium, and magnesium, increased urine output, lower urinary osmolality, and a partial urinary concentrating defect. Concurrent downregulation of Na-Pi-IIa and NKCC2 expression was observed. There was also a decrease in medullar expression of the AQP2 collecting duct water channel. CONCLUSION: Downregulation of Na-Pi-IIa appears to play a crucial role in the downregulation of ACY-induced hyperphosphaturia. The accompanying polyuria and urinary-concentrating defect can in part be explained by the downregulation of NKCC2 and AQP2. 相似文献
52.
Natasha M. Rueth MD MS Darcy Shaw MD Jonathan D’Cunha MD PhD Chinsoo Cho MD Michael A. Maddaus MD Rafael S. Andrade MD 《Annals of surgical oncology》2012,19(13):4223-4228
Background
Esophageal stents provide immediate palliation of malignant dysphagia; however, radiotherapy (RT) is a superior long-term option. We review the outcomes of combined esophageal stenting and RT for patients with malignant dysphagia.Methods
We retrospectively reviewed patients with esophageal stents placed for palliation of malignant dysphagia from esophageal stricture, esophageal extrinsic compression, or malignant tracheoesophageal fistula (TEF). We excluded patients with radiation-induced TEF in the absence of tumor. We analyzed and compared outcomes between patients with no RT, RT before stent placement, and RT after stent placement.Results
We placed stents in 45 patients for esophageal stricture from esophageal cancer (n?=?30; 66.7?%), malignant TEF (n?=?8; 17.7?%), and esophageal compression from airway, mediastinal, or metastatic malignancies (n?=?7; 15.6?%). Twenty patients (44.4?%) had no RT; 25 patients had RT before stent placement (n?=?16; 35.6?%), RT after stent placement (n?=?8; 17.8?%), or both (n?=?1; 2.2?%). Median follow-up was 30?days. Complications requiring stent revision were similar with or without RT. Subjective symptom relief was achieved in 68.9?% of all patients, with no differences noted between groups (p?=?0.99). The 30-day mortality was 15.6?%. Patients with RT after stent placement had a longer median survival compared to those without RT (98 vs. 38?days).Conclusions
Esophageal stent placement with RT is a safe approach for malignant dysphagia. 相似文献53.
54.
Laura Andrade Rocha Carlos Eli Piccinato Mauricio Serra Ribiero Christiane Becari Renata Dellalibera Joviliano Edwaldo Edner Joviliano 《Journal of vascular surgery》2017,65(1):119-127
Objective
The purpose of this study was to investigate the roles of the kallikrein-kinin system and matrix metalloproteinases (MMPs) in the development of arterial restenosis attributable to intimal hyperplasia in the femoropopliteal arteries.Methods
This report describes a single-center prospective study of 27 patients with peripheral artery disease who required percutaneous transluminal angioplasty and stenting of the femoropopliteal segment using covered stent grafts. The blood concentrations of total and kininogen fractions were evaluated using immunoenzymatic methods. Plasma kallikrein was evaluated by the colorimetric method. Tissue kallikrein was evaluated by the spectrophotometric method. The activity of kininase II was measured by fluorometric analysis. Quantification of MMPs was performed by zymography, and tissue inhibitors of metalloproteinases were measured by enzyme-linked immunosorbent assay.Results
Four (15%) of the treated patients developed restenosis at the 6-month follow-up evaluation. These patients had significantly lower levels of high-molecular-weight kininogens (24 hours; P < .05) and low-molecular-weight kininogens (before, P < .05; 24 hours, P < .01; 6 months, P < .05) and lower levels of tissue inhibitor of metalloproteinases-2 (6 months; P < .05) than the patients without restenosis. The activity levels of plasma and tissue kallikrein, kininase II, and MMPs did not differ significantly between the patients with and without restenosis.Conclusions
This study demonstrates an involvement of the kallikrein-kinin system in in-stent restenosis, although we could not confirm the participation of metalloproteinases in the restenosis process. 相似文献55.
de Andrade AK Feist IS Pannuti CM Cai S Zezell DM De Micheli G 《Lasers in medical science》2008,23(4):341-347
The Nd:YAG laser efficacy associated with conventional treatment for bacterial reduction has been investigated throughout
literature. The purpose of this study was to evaluate the bacterial reduction after Nd:YAG laser irradiation associated with
scaling and root planning in class II furcation defects in patients with chronic periodontitis. Thirty-four furcation lesions
were selected from 17 subjects. The control group received conventional treatment, and the experimental group received the
same treatment followed by Nd:YAG laser irradiation (100 mJ/pulse; 15 Hz; 1.5 W, 60 s, 141.5 J/cm2). Both treatments resulted in improvements of most clinical parameters. A significant reduction of colony forming unit (CFU)
of total bacteria number was observed in both groups. The highest reduction was noted in the experimental group immediately
after the treatment. The number of dark pigmented bacteria and the percentage of patients with Porphyromonas gingivalis, Prevotella intermedia, and Actinobacillus actinomycetemcomitans reduced immediately after the treatment and returned to values close to the initial ones 6 weeks after the baseline for both
groups. The Nd:YAG laser associated with conventional treatment promoted significant bacterial reduction in class II furcation
immediately after irradiation, although this reduction was not observed 6 weeks after the baseline. 相似文献
56.
Survival, integration, and axon growth support of glia transplanted into the chronically contused spinal cord 总被引:7,自引:0,他引:7
Barakat DJ Gaglani SM Neravetla SR Sanchez AR Andrade CM Pressman Y Puzis R Garg MS Bunge MB Pearse DD 《Cell transplantation》2005,14(4):225-240
Due to an ever-growing population of individuals with chronic spinal cord injury, there is a need for experimental models to translate efficacious regenerative and reparative acute therapies to chronic injury application. The present study assessed the ability of fluid grafts of either Schwann cells (SCs) or olfactory ensheathing glia (OEG) to facilitate the growth of supraspinal and afferent axons and promote restitution of hind limb function after transplantation into a 2-month-old, moderate, thoracic (T8) contusion in the rat. The use of cultured glial cells, transduced with lentiviral vectors encoding enhanced green fluorescent protein (EGFP), permitted long-term tracking of the cells following spinal cord transplantation to examine their survival, migration, and axonal association. At 3 months following grafting of 2 million SCs or OEG in 6 microl of DMEM/F12 medium into the injury site, stereological quantification of the three-dimensional reconstructed spinal cords revealed that an average of 17.1 +/- 6.8% of the SCs and 2.3 +/- 1.4% of the OEG survived from the number transplanted. In the OEG grafted spinal cord, a limited number of glia were unable to prevent central cavitation and were found in patches around the cavity rim. The transplanted SCs, however, formed a substantive graft within the injury site capable of supporting the ingrowth of numerous, densely packed neurofilament-positive axons. The SC grafts were able to support growth of both ascending calcitonin gene-related peptide (CGRP)-positive and supraspinal serotonergic axons and, although no biotinylated dextran amine (BDA)-traced corticospinal axons were present within the center of the grafts, the SC transplants significantly increased corticospinal axon numbers immediately rostral to the injury-graft site compared with injury-only controls. Moreover, SC grafted animals demonstrated modest, though significant, improvements in open field locomotion and exhibited less foot position errors (base of support and foot rotation). Whereas these results demonstrate that SC grafts survive, support axon growth, and can improve functional outcome after chronic contusive spinal cord injury, further development of OEG grafting procedures in this model and putative combination strategies with SC grafts need to be further explored to produce substantial improvements in axon growth and function. 相似文献
57.
Efficacy and safety of a cisplatin and paclitaxel induction regimen followed by chemoradiotherapy for patients with locally advanced head and neck squamous cell carcinoma 下载免费PDF全文
Luciano de Souza Viana MD PhD Felipe Coelho de Aguiar Silva MD Alexandre Andrade dos Anjos Jacome MD PhD Danielle Calheiros Campelo Maia MD PhD Marcos Duarte de Mattos MD MSc Alexandre Arthur Jacinto MD Augusto Elias Mamere MD PhD Domingos Boldrini Junior MD MSc Renato de Castro Capuzzo MD Carlos Roberto Santos MD Andre Lopes Carvalho MD PhD 《Head & neck》2016,38(Z1):E970-E980
58.
Ana Flávia Marçal Pessoa PhD Juliana Costa Florim MSc Hosana Gomes Rodrigues PhD Vinicius Andrade‐Oliveira PhD Simone A. Teixeira PhD Kaio Fernando Vitzel PhD Rui Curi PhD Niels Olsen Saraiva Câmara PhD Marcelo N. Muscará PhD Marcelo Lazzaron Lamers PhD Marinilce Fagundes Santos PhD 《Wound repair and regeneration》2016,24(6):981-993
Oxidative stress aggravates several long‐term complications in diabetes mellitus. We evaluated the effectiveness of the oral administration of antioxidants (vitamins E and C, 40 and 100 mg/kg b.w., respectively) on skin wound healing acceleration in alloxan‐induced diabetic mice. Mice were wounded 30 days after the induction of diabetes. Antioxidants were effective in preventing oxidative stress, as assessed by TBARS. The enzymes catalase, glutathione reductase, glutathione peroxidase, and superoxide dismutase were increased in diabetics on the 3rd day post‐wounding; catalase and glutathione peroxidase remained still augmented in diabetics after 14th day postwounding, and the treatment with vitamins restored their activities to control. After 3 days, diabetic mice showed lower infiltration of inflammatory cells (including CD11b+ and Ly6G+ cells) and reduced levels of KC, TNF‐α, IL‐1β, and IL‐12 p40 when compared with control mice. The treatment restored cytokine levels. After 14 days, diabetic mice showed late wound closure, persistent inflammation and delayed reepithelialization, accompanied by an increase in MIG+/CD206? macrophages whereas CD206+/MIG? macrophages were decreased. Cytokines IL‐12p40, TNF‐α, IL‐1β, and KC were increased and normal levels were restored after treatment with antioxidants. These results suggest that oxidative stress plays a major role in diabetic wound healing impairment and the oral administration of antioxidants improves healing by modulating inflammation and the antioxidant system with no effect on glycemia. 相似文献
59.
Cristiano Feijó Andrade Thomas K. Waddell Shaf Keshavjee Mingyao Liu 《American journal of transplantation》2005,5(5):969-975
Traditionally, the recognition and tolerance of transplanted grafts has been considered to be within the realm of the adaptive immune system. Innate immunity, on the other hand, as the first line of host defense, plays a role in fighting against invading microorganisms. Recently, with the discovery of the Toll-like receptors (TLRs), the role of innate immune responses in the control of adaptive immunity has become a new area of interest. Emerging evidence suggests that in addition to responding to pathogen-associated molecular patterns of microorganisms, TLRs can be activated by endogenous ligands, expressed by mammalian cells. These 'danger signals' may participate in ischemia-reperfusion related organ damage and subsequently influence function and survival of transplanted grafts. Furthermore, it has been suggested that adaptive immune responses can enhance the acute inflammatory responses controlled by innate immunity in organ transplantation. This review addresses the potential involvement of TLRs in different stages of organ transplantation. Intriguing and controversial findings are presented and discussed in order to stimulate more attention to this emerging and potentially important area of research in organ transplantation. 相似文献
60.
An epidemic amongst recruits who presented with acute viral exudative pleural effusion with lymphocytic pleocytosis is analysed. Histologic and bacteriologic proof of tuberculosis was lacking in majority. Most of them recovered without pleural thickening. Overcrowding, inadequate clothing protection, stress and strain of vigorous recruit training could be important precipitating factors. None reported with parenchymal tuberculosis in two year follow up.KEY WORDS: Pleural effussion, Viral 相似文献