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141.
Forty-one proved cases of acute acalculous cholecystitis imaged with technetium-99m iminodiacetic acid (IDA) cholescintigraphy were retrospectively analyzed. After the exclusion of one indeterminate scan (showing poor initial hepatic uptake and excretion), the study yielded a 92.5% (37 of 40) sensitivity for the detection of cystic or common bile duct obstruction. Each of the three patients with false-negative scintigrams had other abnormal scintigraphic findings suggestive of biliary tract disease. Of the 20 patients (48.8%) with focal or diffuse gangrenous cholecystitis or perforation, seven (35%) exhibited either free peritoneal spill or increased pericholecystic activity to indicate the presence of advanced disease. 相似文献
142.
Biodegradable microspheres for protein delivery 总被引:29,自引:0,他引:29
In a very short time, since their emergence, the field of controlled delivery of proteins has grown immensely. Because of their relatively large size, they have low transdermal bioavailabilities. Oral bioavailability is generally poor since they are poorly absorbed and easily degraded by proteolytic enzymes in the gastrointestinal tract. Ocular and nasal delivery is also unfavorable due to degradation by enzymes present in eye tissues and nasal mucosa. Thus parenteral delivery is currently most demanding and suitable for delivery of such molecules. In systemic delivery of proteins, biodegradable microspheres as parenteral depot formulation occupy an important place because of several aspects like protection of sensitive proteins from degradation, prolonged or modified release, pulsatile release patterns. The main objective in developing controlled release protein injectables is avoidance of regular invasive doses which in turn provide patient compliance, comfort as well as control over blood levels. This review presents the outstanding contributions in field of biodegradable microspheres as protein delivery systems, their methods of preparation, drug release, stability, interaction with immune system and regulatory considerations. 相似文献
143.
Relangi Hitesh Srinivasa Krishna Naidu G. S. R. S. N. K. Sharma Vikas Kumar Mahendra Dhir Varun Sharma Shefali K. Sharma Aman Minz Ranjana W. Jain Sanjay 《Clinical and experimental medicine》2022,22(4):613-620
Clinical and Experimental Medicine - The objectives of this study were to describe the clinical features and evaluate the utility of immunological features as predictors of organ involvement and... 相似文献
144.
Ashwani Kumar Varun Dhir Shefali Sharma Aman Sharma Surjit Singh 《Clinical therapeutics》2017,39(1):150-158
Purpose
Triamcinolone hexacetonide (TH), triamcinolone acetonide (TA), and methylprednisolone acetate (MPA) are commonly used intra-articular steroid preparations. Studies suggest that intra-articular TH is more efficacious than MPA and TA in chronic inflammatory arthritis. However, it is unclear which of the latter two preparations has better efficacy. Thus, we compared intra-articular knee injections of MPA and TA in patients with chronic inflammatory arthritis.Methods
This double-blind, randomized controlled trial included patients with rheumatoid arthritis or spondyloarthritis with an acutely swollen knee joint (≥1 week, <24 weeks). They were randomly assigned (1:1) to intra-articular knee injection with MPA or TA (80 mg, 2 mL of each). Evaluations were performed at 4, 12, and 24 weeks. Primary outcome was time to relapse (Kaplan-Meier) over 24 weeks, with relapse defined as return to baseline pain or swelling ≥1 week. Secondary outcomes were change in pain and swelling (using a numerical rating scale), range of movement, and occurrence of adverse effects. Primary analysis was intention to treat, with last observation carried forward.Findings
One hundred patients (89 with rheumatoid arthritis) were randomly assigned in equal numbers to the MPA and TA groups. Nine patients relapsed in each group over 24 weeks. The mean time to relapse was not significantly different between the MPA and TA groups (20.8 [95% CI, 18.8–22.7] weeks and 20.9 [95% CI, 19.0–22.8] weeks, respectively; P = 0.9; hazard ratio = 1.0 [95% CI, 0.4–2.5]). In both groups, there was a significant decline in pain and swelling scores at all visits (P < 0.001); however, there were no significant intergroup differences. At 24 weeks, mean change in pain in the MPA (–4.4 [3.1]) and TA groups (–3.9 [2.8]) was not significantly different (P = 0.46). No infection, hematoma or hypopigmentation occurred in any patient. In addition, no significant intergroup differences were found in joint swelling, range of movement, modified (28 joint) Disease Activity Score using 3 variables, or Health Assessment Questionnaire over 24 weeks.Implications
No significant differences were found in efficacy between intra-articular knee injections with MPA and TA in these patients with chronic inflammatory arthritis. However, results need to be extrapolated cautiously because of the small sample size. Three-quarters of the patients remained relapse free at 24 weeks. Clinical Trials Registry of India (www.ctri.nic.in) identifier: CTRI/2015/09/006187. 相似文献145.
目的:为获得组织工程化自体血管,观察体外静态培养条件下犬内皮细胞与平滑肌细胞联合培养组织学及形态学的特征。方法:实验于2004-07/2005-06在首都医科大学宣武医院外科院级实验室完成。①实验材料:雄性杂种犬,3个月龄,体质量8~12kg。②实验方法:贴块法及酶解法对犬内皮细胞及平滑肌细胞进行原代分离培养及扩增,将第Ⅱ代平滑肌细胞以1×109L-1的密度种植于胶原膜上培养13d,再将第Ⅱ代内皮细胞接种于生长平滑肌细胞的胶原膜上2d。③实验评估:行苏木精-伊红染色同时扫描电镜和透射电镜观察平滑肌细胞和内皮细胞在胶原载体上联合培养后的形态。结果:苏木精-伊红染色见平滑肌细胞较均匀的分布于支架材料表面及内部;扫描电镜下,平滑肌细胞可以在胶原载体材料上生长,增殖明显并在短期内形成多层细胞。内皮细胞与平滑肌细胞联合培养2d就可在平滑肌细胞层表面获得连续的单层内皮细胞层。结论:在短期静态培养条件下犬的血管平滑肌细胞和内皮细胞可以在胶原载体材料上形成具有两层细胞结构的组织工程化动脉血管组织片。 相似文献
146.
Mixed cryoglobulinemia, renal syndromes, lymphoproliferative disorders, Sj?gren syndrome, porphyria cutanea tarda, and neuropathies are all strongly associated with hepatitis C virus (HCV) infection. Diabetes, thyroid disease, and the presence of autoantibodies in the serum are also linked to HCV, but less strongly. The pathophysiologic basis for most of these syndromes seems immunologic. Cirrhosis and chronic HCV infection seem to be risk factors. 相似文献
147.
Warfield KL Perkins JG Swenson DL Deal EM Bosio CM Aman MJ Yokoyama WM Young HA Bavari S 《The Journal of experimental medicine》2004,200(2):169-179
Ebola virus is a highly lethal human pathogen and is rapidly driving many wild primate populations toward extinction. Several lines of evidence suggest that innate, nonspecific host factors are potentially critical for survival after Ebola virus infection. Here, we show that nonreplicating Ebola virus-like particles (VLPs), containing the glycoprotein (GP) and matrix protein virus protein (VP)40, administered 1-3 d before Ebola virus infection rapidly induced protective immunity. VLP injection enhanced the numbers of natural killer (NK) cells in lymphoid tissues. In contrast to live Ebola virus, VLP treatment of NK cells enhanced cytokine secretion and cytolytic activity against NK-sensitive targets. Unlike wild-type mice, treatment of NK-deficient or -depleted mice with VLPs had no protective effect against Ebola virus infection and NK cells treated with VLPs protected against Ebola virus infection when adoptively transferred to naive mice. The mechanism of NK cell-mediated protection clearly depended on perforin, but not interferon-gamma secretion. Particles containing only VP40 were sufficient to induce NK cell responses and provide protection from infection in the absence of the viral GP. These findings revealed a decisive role for NK cells during lethal Ebola virus infection. This work should open new doors for better understanding of Ebola virus pathogenesis and direct the development of immunotherapeutics, which target the innate immune system, for treatment of Ebola virus infection. 相似文献
148.
Aman Dhawan 《Arthroscopy》2018,34(6):1869-1870
Revision hip arthroscopy, like primary hip arthroscopy, is being performed more frequently. Questions remain regarding the clinical value of this surgical intervention, especially considering previous studies that demonstrate lower baseline patient-reported outcomes scores before and after surgery. Evaluation of the clinical utility and value of revision hip arthroscopy, and indeed all surgical interventions, need be performed using validated patient-reported outcomes in light of these clinically significant thresholds and changes, beyond just statistical differences. 相似文献
149.
Blood group A immunodeterminants on human red cells differ in biologic activity and sensitivity to alpha-N-acetylgalactosaminidase 总被引:1,自引:0,他引:1
BACKGROUND: Epitopes of blood group A antigen can be enzymatically cleaved from red cells (RBCs), but the extent of cleavage required for normal survival in allogeneic blood transfusion recipients is unknown. Therefore, the cleavage rates were studied for A antigen epitope binding of 1) complement-activating anti-A, 2) Dolichos biflorus anti- A, lectin, and 3) hemagglutinating anti-A during incubation with a purified alpha-N-acetylgalactosaminidase, E.C. 3.2.1.49 (alpha- GalNAc'ase). STUDY DESIGN AND METHODS: Suspensions of group A RBCs were incubated with alpha-GalNAc'ase. Cells were removed at intervals, washed, and tested for loss of binding by monoclonal, polyclonal, and complement-activating anti-A, D. biflorus anti-A1 lectin, and Ulex europaeus anti-H lectin. RESULTS: A epitopes binding D. biflorus lectin were highly susceptible to alpha-GalNAc'ase; simultaneously with their loss, binding with U. europaeus lectin emerged. Loss of complement- mediated hemolysis was slower. A epitopes binding hemagglutinating anti- A were most resistant. Cleavage of A epitopes from membrane glycosphingolipids with short oligosaccharide chains was similarly resistant. Rates of cleavage from A1 and A2 RBCs were similar. CONCLUSION: RBC epitopes of blood group A differ in susceptibility to cleavage and biologic reactivity, which suggests that subsets mediating important biologic functions exist on functionally and topographically distinct membrane glycoconjugates. 相似文献
150.
Video capsule endoscopy (VCE), an important innovation in diagnostic endoscopy, was approved in 2001 and is now widely available. In this system, the patient swallows a miniature high-resolution camera that is propelled by peristalsis through the gastrointestinal tract. It is particularly useful in examining the small intestine, which is difficult to visualize by conventional endoscopic techniques. 相似文献