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61.

Purpose

Neuroendocrine tumours of the pancreas (pNET) are observed in 8 – 17 % of patients with von Hippel-Lindau disease (vHLD), and 11 – 20 % of these patients develop metastatic disease. MRI and CT have a very high resolution; however, their sensitivity and specificity for the detection of pNET amongst cystic lesions in the pancreas of vHLD patients are generally considered insufficient. In contrast, 68Ga-DOTATOC PET/CT demonstrates a high sensitivity for the diagnosis and staging of neuroendocrine tumours. In this study we investigated the potential role of 68Ga-DOTATOC PET/CT in screening of patients with vHLD.

Method

68Ga-DOTATOC PET/three-phase contrast-enhanced CT was performed according to guidelines in all consecutive vHLD patients between January 2012 and November 2015. All patients underwent additional MRI imaging of the abdomen, spine, and head. Chromogranin A (CgA) was determined at the time of the PET/CT examination. A lesion seen on 68Ga-DOTATOC PET in the pancreas was defined as positive if the uptake was visually higher than in the surrounding tissues. Lesions were quantified using maximum SUV.

Results

Overall, 20 patients (8 men, 12 women; mean age 44.7?±?11.1 years) were prospectively examined. Genetically, 12 patients had type 1 vHLD and 8 had type 2 vHLD. 68Ga-DOTATOC PET/CT detected more pNET than morphological imaging (CT or MRI): 11 patients (55 %; 8 type 1, 3 type 2) vs. 9 patients (45 %; 6 type 1, 3 type 2). The concentration of CgA was mildly elevated in 2 of 11 patients with pNET. The mean SUVmax of the pancreatic lesions was 18.9?±?21.9 (range 5.0 – 65.6). Four patients (36.4 %) had multiple pNETs. The mean size of the lesions on CT and/or MRI was 10.4?±?8.3 mm (range 4 – 38 mm), and 41.1 % were larger than 10 mm. In addition, somatostatin receptor-positive cerebellar and spinal haemangioblastomas were detected in three patients (SUVmax 2.1 – 10.1). One patient presented with a solitary somatostatin receptor-positive lymph node metastasis. pNETs were observed more frequently in vHLD type 1 than type 2 (66.7 % vs. 37.5 %, p?=?0.089). None of the patients showed progressive disease during follow-up.

Conclusion

In this study, 68Ga-DOTATOC PET detected pNETs in a higher proportion of patients with vHLD than found in previous studies with 111In-octreoscan, the imaging method recommended by the NCCN. We therefore suggest 68Ga-DOTATOC PET/CT as the more sensible screening tool.
  相似文献   
62.
Bloodstream infections (BSIs) are common, however international guidelines are available only for methicillin-resistant Staphylococcus aureus (MRSA) bacteraemia and candidaemia. This international ESCMID cross-sectional survey, open from December 2016 to February 2017, explored the management of BSIs by infection specialists. All infection specialists (senior or trainees) giving at least weekly advice on positive blood cultures could participate. Their practices were evaluated using six clinical vignettes presenting uncomplicated BSI cases. A total of 616 professionals from 56 countries participated [333/616 (54%) infectious diseases specialists, 188/616 (31%) clinical microbiologists], of whom 76% (468/616) were members of an antimicrobial stewardship team. Large variations in practice were noted, in particular for the Escherichia coli, Enterococcus faecalis and Pseudomonas aeruginosa vignettes. Echocardiography was considered standard of care by 81% (373/459) of participants for MRSA, 78% (400/510) for methicillin-susceptible S. aureus and 60% (236/395) for Candida albicans. Antimicrobial combination therapy was recommended by 2% (8/360) of respondents for C. albicans, 11% (43/378) for E. coli, 27% (114/420) for MRSA and 39% (155/393) for E. faecalis. Intravenous-to-oral switch was considered in 68% (285/418) for MRSA, 79% (306/388) for E. faecalis, 72% (264/366) for P. aeruginosa and 75% (270/362) for C. albicans. In multivariable analysis, IDSA guideline-compliant practice was more frequent among participants belonging to an antimicrobial stewardship team (aOR?=?1.7, P?=?0.018 for the MRSA vignette; and aOR?=?2.0, P?=?0.008 for the candidaemia vignette). This survey showed large variations in practice among infection specialists. International guidelines on management of BSI are urgently needed.  相似文献   
63.
64.
International Ophthalmology - Fixation stability (FS) of the preferred retinal locus (PRL) may be improved by biofeedback fixation training (BFT) with microperimetry. Such training can be done on...  相似文献   
65.
66.
BACKGROUND & AIMS: Acute hepatitis C virus infection accounts for approximately 20% of cases of acute hepatitis today. The aim of this study was to define the natural course of the disease and to contribute to the development of treatment strategies for acute hepatitis C virus. METHODS: The diagnosis of acute hepatitis C virus in 60 patients was based on seroconversion to anti-hepatitis C virus antibodies or clinical and biochemical criteria and on the presence of hepatitis C virus RNA in the first serum sample. RESULTS: Fifty-one of 60 (85%) patients presented with symptomatic acute hepatitis C virus. In the natural (untreated) course of acute symptomatic hepatitis C (n = 46), spontaneous clearance was observed in 24 patients (52%), usually within 12 weeks after the onset of symptoms, whereas all asymptomatic patients (n = 9) developed chronic hepatitis C. The start of antiviral therapy (interferon-alpha with or without ribavirin) beyond 3 months after the onset of acute hepatitis induced sustained viral clearance in 80% of treated patients. CONCLUSIONS: The management of acute hepatitis C has to take into account the high rate of spontaneous viral clearance within 12 weeks after the onset of symptomatic disease. Treatment of only those patients who remain hepatitis C virus RNA positive for more than 3 months after the onset of disease led to an overall viral clearance (self-limited and treatment induced) in 91% of patients, and unnecessary treatment was avoided in those with spontaneous viral clearance. Patients with asymptomatic acute hepatitis C virus infection are unlikely to clear the infection spontaneously and should be treated as early as possible.  相似文献   
67.

Introduction

Bloodstream infections (BSI) are frequent infections worldwide. Our objective was to explore variation in the management of patients with BSI by infection specialists in France and Germany.

Methods

This work is part of an international ESCMID cross-sectional internet-based questionnaire survey that was opened from December 2016 to February 2017. All hospital-based infection specialists, senior or trainees, giving at least weekly advice on positive blood cultures could participate. Their practices were evaluated using six clinical vignettes presenting an uncomplicated BSI due to different pathogens.

Results

A hundred and ninety-six professionals (125 from Germany and 71 from France) participated. Systematic expert advice for positive blood cultures was more often available in Germany as compared with France (73 vs. 56%, p = 0.004). In Germany, the professional providing the expert advice was more often a microbiologist or a pharmacist as compared with France (p = 0.001 and p = 0.037, respectively) where it was more often an infectious diseases specialist. Fewer German respondents reported to advise systematic IV-oral switch of antibiotic therapy. German respondents also recommended less often combination therapy: for example for Enterococcus faecalis (64 vs. 43%, p = 0.015), ESBL E. coli (94 vs. 67%, p < 0.001) and Pseudomonas aeruginosa (76 vs. 37%, p < 0.001). Overall, management of candidaemia was more often compliant with the IDSA guidelines in France as compared with Germany, but no difference was noted for MRSA bacteraemia.

Conclusion

Our survey shows that wide variations exist between two neighboring countries in the recommendations by infection specialists for the management of BSI. International guidelines are needed.
  相似文献   
68.
An enhancement of Na+/H+ exchange (NHE) in blood cells of selected patients with essential hypertension and with diabetic nephropathy has been described by various investigators. Recent studies have shown that enhanced NHE activity persists in immortalized lymphoblasts from these patients after prolonged cell culture and, thus, appears to be under genetic control. Available evidence strongly argues against a mutation in the encoding gene or an overexpression of the NHE. Immortalized cells from hypertensive patients with enhanced NHE activity display two-fold enhanced agonistinduced rises of the cytosolic free Ca2+ concentration and the underlying reason was identified as an increased activation of pertussis toxin (PTX)-sensitive G proteins. The molecular mechanism(s) of this phenomenon have not yet been elucidated. It appears likely that similar changes contribute to the enhanced NHE activity phenotype in diabetic nephropathy, although experimental evidence for this is still lacking. An enhanced activation of PTX-sensitive G proteins could explain many of the hitherto unexplained phenomena in essential hypertension, e. g. inheritance, increased vasoconstriction, hypertrophy or remodeling of arterial blood vessels and the heart, enhanced platelet aggregation etc. In diabetes the same defect could provide the basis for the susceptibility to nephropathy, e.g. by enhancing the deleterious effects of autocrine and paracrine growth, factors. Thus, the experimental approach of immortalizing blood cells from patients with essential hypertension and diabetic nephropathy has opened new horizons in the identification of genetically fixed abnomalities in intracellular signal transduction which could contribute to both pathologies and which can now be studied without the confounding influences of the diabetic or hypertensivein vivo milieu.  相似文献   
69.

Purpose

Bacteremia with Staphylococcus aureus (SAB) is a serious clinical condition and is associated with a high mortality, ranging from 20 to 40 %. Different trials from tertiary referral hospitals demonstrate that infectious disease consultation and adherence to standard of care indicators reduce the high mortality. Data from <250-bed general hospitals are lacking in this context.

Methods

Patient cases at a community 200-bed general hospital with documented SAB were retrospectively analyzed from January 2010 to March 2013 regarding defined standard of care indicators. In April 2013, an antibiotic stewardship bundle approach was implemented targeting SAB. Follow-up was available until December 2013. Adherence to the different components of the bundle was analyzed.

Results

There were 64 cases of SAB reported. After exclusion of five cases, 39 cases were included in the pre-intervention period and 20 patients in the post-intervention period. Mean average bundle adherence increased from a baseline score of 0.8–3.7 (p < 0.001) in the post-intervention period, whereas in-hospital mortality decreased significantly (44 vs. 10 %, p < 0.001) despite or even because the absolute number of detected cases of SAB increased substantially after the intervention was initiated.

Conclusion

Although we were unable to identify whether the bundle, one of its components, or procedural improvements are responsible for the success of the intervention, our study indicates that the applied approach is feasible and is accompanied by a significant reduction of in-hospital mortality in the secondary care setting. The intervention may serve as a model for other hospitals with similar structures and baseline situations.  相似文献   
70.
European Journal of Nuclear Medicine and Molecular Imaging - One of the primary prerequisites for peptide receptor radionuclide therapy (PRRT) in patients with neuroendocrine tumors (NET) is the...  相似文献   
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