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排序方式: 共有2943条查询结果,搜索用时 109 毫秒
41.
肿瘤转移相关基因与周围型肺癌CT征象的关系研究   总被引:2,自引:0,他引:2  
摘要目的:探讨VEGF和nm23-H1基因表达水平与周围型肺癌的病理生理学特征和CT征象之间的关系。方法:回顾性分析确诊的47例周围型肺癌患者CT表现.同时采用免疫组化方法(LSAB法)检测47例肺癌组织中的VEGF和nm23-H1表达水平。结果:1)VEGF、nm23-H1表达水平与原发肿瘤大小、淋巴结转移状态,pTNM分期均有密切关系(P<0.05)。2)VEGF与nm23-H1表达水平呈负相关(P<0.05)。3)VEGF基因的高表达和nm23-H1基因的低表达均与分叶征、纵隔淋巴结转移有关(P<0.05),且VEGF的高表达也与空洞征有关:二者表达水平与毛刺征、空泡征、胸膜凹陷征和支气管征均无关(P>0.05)。4)深分叶征、空泡征和支气管征与肿瘤大小有关(P<0.05),而与毛刺征、胸膜凹陷征和纵隔淋巴结转移均无关(P>0.05)。结论:VEGF过度表达和nm23-H1低表达均与周围型肺癌的分叶征、空洞坏死征和纵隔淋巴结转移有密切关系。  相似文献   
42.
Background : A surprisingly high 15 per cent of women in Caucasian societies are carriers of the genes for abnormal colour vision but there is no clinical method to identify them. It has long been known that heterozygotes for the protan colour vision deficiencies can demonstrate a reduced luminous sensitivity to red light. This is known as Schmidt's sign, which is thought to arise from mosaicism (Lyonisation). The Medmont C‐100 colour vision test measures relative spectral sensitivity using flicker photometry to differentiate protans and deutans. It should be able to diagnose Schmidt's sign. Method : We tested six known protan heterozygotes (four whose sons have a protan colour vision deficiency and two whose fathers are protan) with the Medmont C‐100 test. Results : All six heterozygotes made average settings of ‐1.75 or more negative at the Medmont C‐100 test, settings which are at or beyond the boundary of the distribution of settings made by observers with normal colour vision. There have been two previous cases reported in the literature of protan heterozygotes, who made protan settings on the Medmont C‐100 or its predecessor test, the OSCAR. We also tested six daughters of the known heterozygotes, 50 per cent of whom are likely to be heterozygotes. Four of the six (66 per cent) made protan settings on the Medmont C‐100. The other two made normal 0.0 settings. Conclusion : We conclude that the Medmont C‐100 can be used clinically to diagnose carriers of protan colour vision deficiency.  相似文献   
43.
目的:探讨成人股骨头缺血性坏死的X线、CT、MRI表现和病理基础。方法:搜集经临床证实的30例成人股骨头缺血性坏死的X线、CT及MRI影像资料进行回顾性分析。结果:30例病患共累计47个病变股骨头,X线检查漏诊了16个病变股骨头,CT检查漏诊了5个病变股骨头,MR检查诊断了经X线、CT检查后漏诊的5例病变股骨头。结论:骨髓水肿是成人股骨头缺血性坏死的早期影像学表现,MRI“线样征”是诊断早期缺血坏死的特征性表现,MR是目前诊断早期成人股骨头缺血性坏死最敏感、最有效的影像学检查方法。  相似文献   
44.
Objective: To examine the diagnostic utility of applause sign scores for the diagnosis of dementia and mild cognitive impairment. Methods: Consecutive unselected new outpatient referrals to a dedicated cognitive disorders clinic over a 12-month period were administered the clapping test. Criterion diagnosis was by usual clinic assessment using standard diagnostic criteria, blind to applause sign score. Results: Applause sign scores differed significantly (p < 0.001) between diagnostic groups (dementia, mild cognitive impairment, subjective memory complaint) and did not correlate with other cognitive screening instrument scores. Nearly three-quarters of those with an abnormal score had cognitive impairment. Applause sign score was specific but not sensitive for a diagnosis of cognitive impairment. Conclusion: The applause sign supports a diagnosis of dementia or cognitive impairment in high prevalence settings and may be useful in conjunction with other cognitive screening tests.  相似文献   
45.
46.
《Acta orthopaedica》2013,84(3):335-341
Background and purpose?Antibiotic‐impregnated cement is used as a spacer or during re‐implantation surgery for the treatment of infected total hip arthroplasties. The routine use of antibiotic‐impregnated cement during primary or uninfected revision total hip arthroplasty remains controversial. With this meta‐analysis of the published literature, we intended to assess efficacy and safety in the use of antibiotic‐impregnated cement for uninfected arthroplasty.

Methods?Following a detailed literature search, only studies reporting on the outcome of total hip replacement performed with antibiotic cement were included. Strict inclusion criteria were used and studies lacking sufficient sample size or critical data were excluded. 19 studies reporting on 36,033 hip replacements in 35,659 patients met the initial inclusion criteria. The main aim of the meta‐analysis was to determine the rate of deep infection with and without the use of antibiotic cement, and to assess the revision rate and the ultimate survivorship of arthroplasty using antibiotic cement.

Results?The rate of deep infection following primary total hip arthroplasty, at 1.2%, was significantly lower when antibiotic cement was used than when cement without antibiotics was used (2.3%). Similarly, the rate of deep infection following revision total hip arthroplasty when a standard combination of cement and antibiotic—or a custom‐made combination of cement and antibiotic, depending on the results of culture—was used, was almost half of the rate of deep infection when no antibiotics were present in the cement. Overall, the survivorship was 98% (101 failures in 5,178 hips) for primary arthroplasty and 88% (100 failures in 855 hips) for revision arthroplasty. There were no reported adverse events or complications associated with the use of antibiotic‐impregnated cement.

Interpretation?The use of antibiotic‐impregnated cement lowered the infection rate by approximately 50% in primary hip arthroplasty. For revisions of previously infected hips, combinations or culture‐dependent antibiotics lowered infection rates by approximately 40%.  相似文献   
47.
A large-scale national representative community survey of 11,122 persons aged more than 35 years included the investigation of the coincidence of depressive symptoms, vital exhaustion, cardiovascular disorders, stroke, and myocardial infarction. A total of 20.3% of the survey participants reported having experienced a cardiovascular disorder (CVD). Of the subjects reporting a CVD, 52.1% exhibited depressive symptoms (22.0% subthreshold depressive symptoms, 30.1% clinical depression), and 69.7% exhibited vital exhaustion. The authors investigated 3 cardiovascular subgroups: (1) subjects having experienced a myocardial infarction (MI), (2) subjects having experienced stroke, and (3) subjects with a CVD but no experience of either an MI or a stroke. The frequency and severity of depressive symptoms did not differ significantly in the 3 subgroups. CVD subjects with no MI or stroke had almost as high frequencies of depressive symptoms and vital exhaustion as patients who experienced stroke or MI. The strength of relationships between these psychological variables and CVDs do not differ significantly from the relationships between hypertension or diabetes and CVDs. Depressive symptoms and increased vital exhaustion have exceptionally high comorbidity with CVDs. The authors detected the same high comorbidity among patients with a milder CVD and without stroke or MI. The assessment and management of depressive symptoms and vital exhaustion should be routine procedure in clinical cardiology.  相似文献   
48.
BackgroundUnilateral upper-lung field pulmonary fibrosis (upper-PF), which is radiologically consistent with pleuroparenchymal fibroelastosis, develops after thoracic surgery. In most patients with unilateral upper-PF, aberrant intra-/extra thoracic air commonly emerges and an autopsy shows chronic pleuritis, which indicates that pleural involvement is associated with upper-PF development. If so, there may be patients with unilateral upper-PF who have a history of pleural involvement, including tuberculous pleurisy (TP) or asbestos exposure (AE). This study aimed to examine this supposition.MethodsWe examined the radiological reports of all consecutive patients from 2012 to 2018 to investigate whether there were patients having unilateral upper-PF and a history of TP or AE.ResultsEight patients were included in the study. Five patients had a history of TP, and the remaining three had that of AE. All patients were men and had respiratory symptoms, and seven patients presented with restrictive ventilatory impairment. The interval between TP or last AE and upper-PF development was long, with a median of over 20 years. The upper-PF lesion was commonly located in the right lung, and aberrant intrathoracic air was observed in five patients during their clinical course. Additionally, the upper-PF lesion transformed into a cystic lesion in six patients, which resulted in Aspergillus infection in two patients. The prognosis was poor, with a median overall survival of 38 months.ConclusionsUnilateral upper-PF developed even in patients with a history of pleural involvement. Our results indicate that pleural involvement plays an important role in the development of unilateral upper-PF.  相似文献   
49.
《Journal of endodontics》2019,45(11):1296-1306.e3
IntroductionThe current systematic review and meta-analysis aimed to evaluate the success rate of partial pulpotomy in treating permanent posterior teeth with carious vital pulp exposure. A secondary aim was to assess the prognostic factors using a meta-regression.MethodsAn electronic search was performed for studies from January 1950 to November 2018 in the following databases: PubMed, ScienceDirect, and Cochrane. All searches were performed following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. Clinical studies evaluating the success rate of cariously exposed vital human permanent posterior teeth treated with a partial pulpotomy were selected. Only randomized clinical trials and prospective clinical studies were included for evaluation. The Newcastle-Ottawa Scale and the Cochrane Collaboration’s tool were used to evaluate risk assessment.ResultsFrom the 218 studies identified through the initial search, 11 studies qualified for the final analysis (5 randomized clinical trials and 6 prospective studies). The results of the meta-analysis indicate a success rate of 98% (confidence interval [CI]: 0.94–1), 96% (CI: 0.92–0.99), and 92% (CI: 0.83–0.97) after 6 months and 1 and 2 years of follow-up. Examining the probable prognostic factors using meta-regression analysis, only preoperative pulp status (P = .001) was identified as a significant factor, with studies including teeth with the presumptive diagnosis of irreversible pulpitis displaying significantly lower results. The final solution, pulp capping material, apex closure, and the age of the patient did not affect the treatment success rate (P > .05).ConclusionsThe available data suggest that a partial pulpotomy results in high success rates in treating cariously exposed permanent posterior teeth up to 2 years. Six months of monitoring can be considered an appropriate period when evaluating the success of a partial pulpotomy although more clinical and radiographic controls are essential to ensuring success.  相似文献   
50.
Recent evidence suggests that carpal tunnel syndrome (CTS) and brachial biceps tendon rupture (BBTR) represent red flags for ATTR cardiac amyloidosis (ATTR-CA). The prevalence of upper limb tenosynovial complications in conditions entering differential diagnosis with CA, such as HCM or Anderson–Fabry disease (AFD), and hence their predictive accuracy in this setting, still remains unresolved. Objective: To investigate the prevalence of CTS and BBTR in a consecutive cohort of ATTR-CA patients, compared with patients with HCM or AFD and with individuals without cardiac disease history. Participants: Consecutive patients with a diagnosis of ATTR-CA, HCM and AFD were evaluated. A control group of consecutive patients was recruited among subjects hospitalized for noncardiac reasons and no cardiac disease history. The presence of BBTR, CTS or prior surgery related to these conditions was ascertained. Results: 342 patients were prospectively enrolled, including 168 ATTR-CA (141 ATTRwt, 27 ATTRm), 81 with HCM/AFD (= 72 and 9, respectively) and 93 controls. CTS was present in 75% ATTR-CA patients, compared with 13% and 10% of HCM/AFD and controls (P = 0.0001 for both comparisons). Bilateral CTS was present in 60% of ATTR-CA patients, while it was rare (2%) in the other groups. BBTR was present in 44% of ATTR-CA patients, 8% of controls and 1% in HCM/AFD. Conclusions: CTS and BBTR are fivefold more prevalent in ATTR-CA patients compared with cardiac patients with other hypertrophic phenotypes. Positive predictive accuracy for ATTR-CA is highest when involvement is bilateral. Upper limb assessment of patients with HCM phenotypes is a simple and effective way to raise suspicion of ATTR-CA.  相似文献   
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