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Elbasvir is an investigational NS5A inhibitor with in vitro activity against multiple HCV genotypes. Antiviral activity of elbasvir was measured in replicons derived from wild-type or resistant variants of genotypes 1a, 1b, and 3. The barrier to resistance was assessed by the number of resistant colonies selected by exposure to various elbasvir concentrations. In a phase 1b dose-escalating study, virologic responses were determined in 48 noncirrhotic adult men with chronic genotype 1 or 3 infections randomized to placebo or elbasvir from 5 to 50 mg (genotype 1) or 10 to 100 mg (genotype 3) once daily for 5 days. The NS5A gene was sequenced from plasma specimens obtained before, during, and after treatment. Elbasvir suppressed the emergence of resistance-associated variants (RAVs) in vitro in a dose-dependent manner. Variants selected by exposure to high elbasvir concentrations typically encoded multiple amino acid substitutions (most commonly involving loci 30, 31, and 93), conferring high-level elbasvir resistance. In the monotherapy study, patients with genotype 1b had greater reductions in HCV RNA levels than patients with genotype 1a at all elbasvir doses; responses in patients with genotype 3 were generally less pronounced than for genotype 1, particularly at lower elbasvir doses. M28T, Q30R, L31V, and Y93H in genotype 1a, L31V and Y93H in genotype 1b, and A30K, L31F, and Y93H in genotype 3 were the predominant RAVs selected by elbasvir monotherapy. Virologic findings in patients were consistent with the preclinical observations. NS5A-RAVs emerged most often at amino acid positions 28, 30, 31, and 93 in both the laboratory and clinical trial. (The MK-8742 P002 trial has been registered at ClinicalTrials.gov under identifier NCT01532973.)  相似文献   
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Testicular vasculitis (TV) may be part of systemic (testicular) vasculitis (STV) or may exist as single-organ/isolated (testicular) vasculitis (ITV). In the current study we sought to identify clinical and histologic features that distinguish STV from ITV. The distinction was deemed important because it is already well established that in other forms of single organ vasculitis, surgical therapy alone may be curative. We identified patients with biopsy-proven TV from pathology databases from our institution and from an English-language PubMed search. Patients were included if data were available to determine TV extent confidently. Data recorded included clinical, laboratory, and histologic features; treatment; and clinical follow-up. The study included 72 patients with TV (mean age, 42 yr; range, 4-78 yr) (7 from our institution). About 74% of patients presented with painful testicular swelling/mass, 10% with a painless testicular swelling/mass, and 4% with epididymal swelling/mass. Eleven percent had no testicular complaints and vasculitis was discovered at autopsy or in other surgical interventions. Vasculitis involved the testicle in 80.3% of cases, the epididymis in 44.6%, and the spermatic cord in 30.6%. Thirty-seven (51%) patients had ITV and 35 (49%) had STV. No differences between ITV and STV patients were found in regards to age, presenting testicular features, duration of testicular symptoms, and time of follow-up. Compared to ITV patients, STV patients presented more often with constitutional/musculoskeletal symptoms (74.3% vs. 8.3%, respectively; p = 0.0001), elevated erythrocyte sedimentation rate (94.7% vs. 16%; p = 0.0001), and anemia (50% vs. 0%; p = 0.0001). Neoplasm was more frequently suspected in ITV than in STV (74.2% vs. 31.6%; p = 0.001), but only occurred in 2 ITV patients. Long-term glucocorticoid therapy was given only to STV patients, and 59.1% of them also received cytotoxic agents. ITV was diagnosed more often by orchiectomy (81.1% vs. 42.9%; p = 0.001) and less frequently by testicular biopsy (2.7% vs. 28.6%; p = 0.003) than STV. Nongranulomatous inflammation affecting medium-sized vessels occurred in most patients with both ITV and STV. Among STV, polyarteritis nodosa was the most frequently diagnosed (63%), followed by Wegener granulomatosis (17%).In summary, TV occurs as ITV in men usually presenting with a testicular mass in the absence of systemic symptoms and normal laboratory results. In most ITV patients, a testicular neoplasm is initially suspected, and TV is an unexpected finding. After surgical removal, ITV does not require systemic therapy. Polyarteritis nodosa is the systemic vasculitis most frequently associated with testicular involvement.  相似文献   
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Plasma cell myeloma (PCM) is a lymphoproliferative disorder characterized by the malignant growth of monoclonal plasma cells within the bone marrow. Although risk factors for the development of PCM have been identified, the etiology on the majority of patients with PCM remains unclear. Cigarette smoking has been postulated as a potential risk factor for lymphoid malignancies; however, the association with PCM is inconclusive. We have carried out a meta-analysis of observational studies to assess the relationship, if any, between cigarette smoking and PCM. A literature search through December 2011 rendered 4 prospective cohort and 13 case–control studies evaluating such association. Our categorical meta-analysis showed that there is no association between ever, current, and former smokers and PCM.This lack of association was maintained when analyzing by study design, study quality, and geographical area of report. Similarly, meta regression analysis showed no association with the number of cigarettes smoked per day. In conclusion, our meta-analysis shows that there is no relationship between cigarette smoking and an increased incidence of PCM. Future studies should focus on other potential risk factors for PCM.  相似文献   
66.

Background/Purpose

Revisional oesophageal reconstructive surgery carries uncommon and unusual risks related to previous surgery. To provide maximum anatomical detail and facilitate successful outcome, we report a standardised pre-operative investigative strategy for all such patients.

Methods

Prospective 8-month cohort study following the introduction of this strategy. All patients underwent high resolution thoracic contrast CT scan and micro-laryngo-bronchoscopy by a paediatric ENT surgeon in addition to upper gastrointestinal contrast study, oesophagoscopy, and echocardiogram.

Results

Seven children (median age 5.6 months [range 2.2–60]) completed the pathway. Four were referred with recurrence of a previously divided tracheo-oesophageal fistula (3 congenital, 1 acquired) and 3 (all with oesophagostomy) for oesophageal replacement for congenital isolated oesophageal atresia (OA, n = 1) and failed repair of OA with distal TOF with wide gap (n = 2). Overall, unanticipated findings were demonstrated in 6/7 children and comprised severe tracheomalacia and right main bronchus stenosis requiring aortopexy (n = 1), vocal cord palsy (n = 2), extensive mediastinal rotation (n = 1), proximal tracheal diverticulum (n = 1), severe subglottic stenosis requiring airway reconstruction (n = 1), proximal tracheal diverticulum (n = 1), right sided aortic arch (n = 1) and left sided aortic arch (previously reported to be right sided, n = 1).

Conclusions

This standardised approach for this complex group of patients reveals a high incidence of unexpected anatomical and functional anomalies with significant surgical and possible medico-legal implications. We recommend these investigations during the pre-operative work-up prior to all revisional oesophageal surgery.  相似文献   
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Serotonin syndrome is gaining attention in perioperative and chronic pain settings due to the growing prevalence of multimodal therapies that increase serotonin levels and thereby heighten patient risk. A patient's genetic make-up may further increase the risk of serotonin syndrome. A case of serotonin syndrome on emergence after general anesthesia is presented. A subsequent cytochrome P4502D6 genetic test result suggested a potential alteration in metabolism. For this patient, who was taking combination antidepressant medications and receiving common perioperative medicines, additive pharmacodynamic effects converged with a pharmacogenetic predisposition, resulting in serotonin syndrome.  相似文献   
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Objectives Surgical resection in addition to adjuvant radiation with or without chemotherapy is the mainstay of treatment for esthesioneuroblastoma (ENB). However, management of patients with orbital involvement remains controversial. Historically, orbital exenteration has been advocated when there is evidence of periorbital invasion. Recently, the indications for orbital exenteration have become more selective and orbital preservation has been advocated. We report our experience with anterior craniofacial resection and orbital preservation in patients with ENB.Design Retrospective review of all patients diagnosed with esthesioneuroblastoma who underwent traditional open anterior craniofacial resection at the Massachusetts General Hospital/Massachusetts Eye and Ear Infirmary Cranial Base Center from 1997 to 2008.Results Sixteen patients were identified with a mean follow-up of 76 months. All patients underwent anterior craniofacial resection via an open approach and adjuvant proton beam radiation. Six of the 16 patients had evidence of either periorbital or lacrimal sac involvement at the time of surgery. All of these patients underwent periorbital resection to negative histologic margins with preservation of the orbit.Conclusion In our study, patients with ENB and periorbital invasion—who were treated with anterior craniofacial resection and periorbital resection with orbital preservation—had no evidence of decreased survival. In all patients, negative histologic margins of the periorbital resection were achieved.  相似文献   
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