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91.
Despite seasonal influenza vaccines having been routinely used for many decades, influenza A virus continues to pose a global threat to humans, causing high morbidity and mortality each year. The effectiveness of the vaccine is largely dependent on how well matched the vaccine strains are with the circulating influenza virus strains. Furthermore, low vaccine efficacy in naïve populations such as young children, or in the elderly, who possess weakened immune systems, indicates that influenza vaccines need to be more personalized to provide broader community protection. Advances in both vaccine technologies and our understanding of influenza virus infection and immunity have led to the design of a variety of alternate vaccine strategies to extend population protection against influenza, some of which are now in use. In this review, we summarize the progress in the field of influenza vaccines, including the advantages and disadvantages of different strategies, and discuss future prospects. We also highlight some of the challenges to be faced in the ongoing effort to control influenza through vaccination.  相似文献   
92.
As patients with chronic hepatitis C virus (HCV) tend to be older and/or have advanced liver disease in Japan, real‐world data are needed to evaluate safe and effective treatment options. The study aim was to assess safety and effectiveness of ledipasvir/sofosbuvir (LDV/SOF) in a real‐world cohort of Japanese patients with HCV genotype (GT) 1 infection overall and by patient subgroups: elderly, compensated cirrhotic, advanced fibrotic and those with hepatocellular carcinoma (HCC). A large prospective observational study was conducted, enrolling adult patients treated for HCV GT1 infection with LDV/SOF at clinical sites across Japan. Patients were observed for safety outcomes during and 4 weeks after treatment, and for sustained virologic response at 12‐weeks post‐treatment (SVR12). Incidence rates (IRs) of adverse drug reactions (ADRs) and serious ADRs (SADRs) and SVR12 rates were assessed overall and by subgroups. ADR and SADR IRs were low (2.26 and 0.17 per 100 person‐months, respectively) and did not significantly differ in elderly patients or those with presence of compensated cirrhosis, worsening fibrosis or HCC. SVR12 rates were high overall (98.5%) and across subgroups investigated (≥94%), including patients who were elderly (98.2%), treatment‐experienced (97.6%), advanced fibrotic (≥95.8%), had existing NS5A resistance‐associated substitutions reported pre‐treatment (95.0%), compensated cirrhosis (95.7%), HCC (94.0%) and other chronic liver diseases (96.1%). In this large, real‐world observational study of Japanese patients with HCV GT1 infection, LDV/SOF treatment resulted in low incidence of adverse events, with high real‐world effectiveness, even among patients with potentially higher risks of adverse safety outcomes and treatment failure.  相似文献   
93.
Aging tissues present a progressive decline in homeostasis and regenerative capacities, which has been associated with degenerative changes in tissue-specific stem cells and stem cell niches. We hypothesized that amino acids could regulate the stem cell phenotype and differentiation ability of human bone marrow-derived mesenchymal stromal cells (hBMSCs). Thus, we performed a screening of 22 standard amino acids and found that D-tryptophan (10 μM) increased the number of cells positive for the early stem cell marker SSEA-4, and the gene expression levels of OCT-4, NANOG, and SOX-2 in hBMSCs. Comparison between D- and L-tryptophan isomers showed that the latter presents a stronger effect in inducing the mRNA levels of Oct-4 and Nanog, and in increasing the osteogenic differentiation of hBMSCs. On the other hand, L-tryptophan suppressed adipogenesis. The migration and colony-forming ability of hBMSCs were also enhanced by L-tryptophan treatment. In vivo experiments delivering L-tryptophan (50 mg/kg/day) by intraperitoneal injections for three weeks confirmed that L-tryptophan significantly increased the percentage of cells positive for SSEA-4, mRNA levels of Nanog and Oct-4, and the migration and colony-forming ability of mouse BMSCs. L-kynurenine, a major metabolite of L-tryptophan, also induced similar effects of L-tryptophan in enhancing stemness and osteogenic differentiation of BMSCs in vitro and in vivo, possibly indicating the involvement of the kynurenine pathway as the downstream signaling of L-tryptophan. Finally, since BMSCs migrate to the wound healing site to promote bone healing, surgical defects of 1 mm in diameter were created in mouse femur to evaluate bone formation after two weeks of L-tryptophan or L-kynurenine injection. Both L-tryptophan and L-kynurenine accelerated bone healing compared to the PBS-injected control group. In summary, L-tryptophan enhanced the stemness and osteoblastic differentiation of BMSCs and may be used as an essential factor to maintain the stem cell properties and accelerate bone healing and/or prevent bone loss.  相似文献   
94.
Several reports describe that the explant culture of the trabecular bone after collagenase treatment produces mesenchymal stem cells (MSCs). However, the suspended cells had not been intensively examined concerning MSCs. We hypothesized that the cells would acquire the properties of MSCs during their expansion and therefore compared them with marrow aspirate-derived MSCs. Human trabecular bones were washed, digested, filtered, and expanded clonally for 14 days. Their proliferation ability (n = 9) and differentiation potentials for chondrocyte, adipocyte, and osteoblast (n = 6) were similar with those of marrow aspirate-derived MSCs. Epitope and mRNA analysis revealed some differences in both types of cells, which disappeared with expansion and subcultivation. A mixed population of collagenase-released (CR) cells had similar differentiation potentials with CR clone, CD31(+) fraction, and osteoblastic cells. For quantitative study, trabecular bone and bone marrow were harvested by single aspiration using a biopsy needle (n = 16). Although the total nucleated cell number harvested was similar, the colony-forming efficiency of CR cells was approximately 100-fold higher than that of BM cells and more than 1 million CR cells could be obtained in 14 days from all donors. Enzymatically released cells from trabecular bone became virtually identical to marrow aspirate-derived MSCs, demonstrating that a trabecular bone fragment can be an alternative source of MSCs.  相似文献   
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96.
Engagement of the mast cell high-affinity receptor for immunoglobulin E (IgE), FcRI, induces tyrosine phosphorylation of Syk, a non-receptor tyrosine kinase, that has been demonstrated as critical for degranulation. Herein we describe a synthetic compound, ER-27319, as a potent and selective inhibitor of antigen or anti-IgE-mediated degranulation of rodent and human mast cells. ER-27319 affected neither Lyn kinase activity nor the antigen-induced phosphorylation of the FcRI but did effectively inhibit the tyrosine phosphorylation of Syk and thus its activity. As a consequence, tyrosine phosphorylation of phospholipase C-γ1, generation of inositol phosphates, release of arachidonic acid, and secretion of histamine and tumor necrosis factor α were also inhibited. ER-27319 did not inhibit the anti-CD3-induced tyrosine phosphorylation of phospholipase C-γ1 in Jurkat T cells, demonstrating a specificity for Syk-induced signals. In contrast the tyrosine phosphorylation and activation of Syk, induced by in vitro incubation with the phosphorylated immunoreceptor tyrosine-based activation motif (ITAM) of FcRI γ subunit or by antigen activation of RBL-2H3 cells, was specifically inhibited by ER-27319. However, when ER-27319 was added to immunoprecipitated Syk, derived from activated cells, no effect was seen on Syk activity. ER-27319 did not inhibit the tyrosine phosphorylation of Syk induced by activation in the presence of Igβ ITAM or the anti-IgM-induced phosphorylation of Syk in human peripheral B cells. Therefore, ER-27319 selectively interferes with the FcRI γ phospho-ITAM activation of Syk in vitro and in intact cells. These results confirm the importance of Syk in FcRI-mediated responses in mast cells and demonstrate the mast cell selectivity and therapeutic potential of ER-27319 in the treatment of allergic disease.  相似文献   
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99.

Background

The rotator cuff plays a significant role in the static and dynamic stability of the glenohumeral joint. Rotator cuff tears may occur after shoulder dislocations, whether in younger athletes or older patients with age-related tendon degeneration. Untreated tears may cause persistent pain, dysfunction, instability, and degenerative changes. A thorough understanding of when to look for rotator cuff tears after shoulder dislocations and how best to manage them may decrease patients’ pain and improve function.

Questions/purposes

We systematically reviewed the available literature to better understand (1) when a rotator cuff tear should be suspected after a dislocation, (2) whether surgical or nonsurgical approaches result in better scores for pain and satisfaction in patients with rotator cuff tears resulting from shoulder dislocations, and (3) whether intraarticular lesions, rotator cuff tears, or both should be addressed when surgery is performed.

Methods

We systematically searched MEDLINE®, CINAHL, and EMBASE for studies published from 1950 to 2012. We included studies reporting outcomes after treatment in patients with rotator cuff tears and shoulder dislocations. We excluded case reports, studies without any treatment, and studies about patients treated with arthroplasty. Five Level III and six Level IV studies were ultimately selected for review.

Results

Patients with persistent pain or dysfunction after a shoulder dislocation often had a concomitant rotator cuff tear. Surgical repair resulted in improved pain relief and patient satisfaction compared to nonoperative management. Repair of the rotator cuff, along with concomitant capsulolabral lesions, helped restore shoulder stability. While these findings are based on Level III and IV evidence, better long-term studies with larger cohorts are needed to strengthen evidence-based recommendations.

Conclusions

Persistent pain and dysfunction after a shoulder dislocation should prompt evaluation of the rotator cuff, especially in contact or overhead athletes, patients older than 40 years, or those with nerve injury. Surgery should be considered in the appropriately active patient with a rotator cuff tear after dislocation. While the current literature suggests improved stability and function after surgical repair of the rotator cuff, higher-quality prospective studies are necessary to make definitive conclusions.  相似文献   
100.

INTRODUCTION

Low back pain is common during pregnancy. However, the incidence of symptomatic lumbar disc herniation during pregnancy is very rare. We report a case of lumbar disc herniation underwent discectomy just after cesarean delivery in the third trimester of pregnancy.

PRESENTATION OF CASE

A 33-year-old woman presented at 32 weeks gestation. She had a low back pain and the left-sided leg pain below the knee. At 34 weeks gestation, she had severe weakness of the left extension halluces longus, left ankle dorsiflexion. MRI showed a large disc herniation at L4/5 expanded to the spinal canal more. The cesarean delivery was performed in the supine position. The patient was then turned to a prone position, and a left L4/5 discectomy was performed. But the day after surgery, she had a severe low back pain and the right leg pain below the knee. MRI showed a disc herniation at L4/5 on the right side of the spinal canal. At 6 days after the first surgery, a right L4/5 discectomy was performed. In the immediate postoperative period, the patient experienced complete relief of the right leg pain.

DISCUSSION

It is necessary to cooperate with a pediatrician, an obstetrician, and an anethesiologists. For obtaining the best outcome on mother and child, it is important to discuss in advance to be able to respond quickly for changeable situation.

CONCLUSION

It is necessary to conduct the operation under pregnancy in consideration of the great influence on mother and child.  相似文献   
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