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排序方式: 共有151条查询结果,搜索用时 15 毫秒
51.
A comparative study of 96 Spline and Threadloc implants is presented. The authors examined the possibility of the failure of the retaining screws of two different antirotational systems (the Threadloc system with hexagonal polyhedral extension and the Spline system), and the possible incorrect link between the abutment and the transfer. After an observation period of 36 months starting from the day of prosthesis insertion, three single Threadloc fixtures (20%) and five pairs of joint Threadloc fixtures (5.7%) presented problems and a partial prosthetic screw loosening. For the Spline series fixtures, no screw loosening was encountered. Regarding the safety of the link between abutment and implant, the best results were obtained from the Spline system, which did not hinder the dentist in positioning the link with the abutment. This is the result of the different geometries of the two antirotational mechanisms which are present on the two fixtures. It is believed that the precise contact between the abutment and the fixture avoids the triggering of a phlogistic process, which can develop into periimplantitis. Therefore, when hex systems are used, an x-ray, which verifies this correct situation, is always recommended during the follow-up.  相似文献   
52.
The authors describe a unique case of left synovial otorrhea in a masticatory phase, occurring in a 64-year-old patient after a long dental sitting. The otoscopic examination and the transverse CT of the ear revealed the fracture of the anterior wall of left external auditory canal and the presence of a small bone fragment on the external side of the glenoid fossa. This situation, at present, has been judged inoperable by otologists due to the close relationship between this area and the head of the left condyle, probably responsible for the fracture. The therapy used was based on the use of a masticatory bite plate, with the aim of increasing the vertical dimension of the jaws during mastication and, so, to keep the condyle in a forward position. The result obtained was the decrease and then the halting of the liquid exit in the auricle, through an increase of the bite plate height determined by the ex iuvantibus method. This temporary therapy could bring about a spontaneous healing of the fracture, thanks to the masticatory increase of the bite plate; but if this is not possible, a fixed prosthetic solution should then be provided for the patient. Research into the literature revealed no similar observations.  相似文献   
53.

Background

Myocardial perfusion scintigraphy (MPS) represents a key prognostic tool, but its predictive yield is far from perfect. We developed a novel clinically relevant segmentation method and a corresponding maximal ischemia score (MIS) in order to risk-stratify patients undergoing MPS.

Methods

Patients referred for MPS were identified, excluding those with evidence of myocardial necrosis or prior revascularization. A seven-region segmentation approach was adopted for left ventricular myocardium, with a corresponding MIS distinguishing five groups (no, minimal, mild, moderate, or severe ischemia). The association between MIS and clinical events was assessed at 1 year and at long-term follow-up.

Results

A total of 8,714 patients were included, with a clinical follow-up of 31 ± 20 months. Unadjusted analyses showed that subjects with a higher MIS were significantly different for several baseline and test data, being older, having lower ejection fraction, and achieving lower workloads (P < .05 for all). Adverse outcomes were also more frequent in patients with higher levels of ischemia, including cardiac death, myocardial infarction (MI), and their composites (P < .05 for all). Differences in adverse events remained significant even after extensive multivariable adjustment (hazard ratio for each MIS increment = 1.57 [1.29-1.90], P < .001 for cardiac death; 1.19 [1.04-1.36], P = .013 for MI; 1.23 [1.09-1.39], P = .001 for cardiac death/MI).

Conclusions

Our novel segmentation method and corresponding MIS efficiently yield satisfactory prognostic information.  相似文献   
54.
We investigated the effect of treatment with peptide T on severe psoriasis in 5 patients. Within 2 months, peptide T led to complete remission of all lesions in 1 patient and to good improvement in 3 others. In 1 patient, no effect was observed.  相似文献   
55.

Background

Myocardial perfusion scintigraphy (MPS) has an established diagnostic and prognostic role in patients with or at risk for coronary artery disease, with ischemia severity and extent having already been identified as key predictors. Whether this is affected by the location of myocardial ischemia is uncertain. We aimed at comparing the prognostic outlook of patients undergoing MPS according to the site of ischemia.

Methods

Our institutional database was queried for subjects undergoing MPS, without myocardial necrosis or recent revascularization. We focused on the prognostic impact of location of vessel-related ischemia (VRI) at MPS, distinguishing four mutually exclusive groups: single-VRI involving left anterior descending (LAD), single-VRI not involving LAD, multi-VRI involving LAD, and multi-VRI not involving LAD. The primary outcome was the long-term (>1 year) rate of death or myocardial infarction (D/MI).

Results

A total of 13,254 patients were included. Moderate or severe VRI occurred in 2,627 (20%) patients. Clinical outcomes were significantly different among the groups of patients with moderate or severe VRI, including death, cardiac death, non-fatal myocardial infarction or their composites (overall P < .001). Specifically, and excluding subjects undergoing revascularization as first follow-up event, D/MI occurred in 8.4% of patients with single-VRI involving LAD, 5.5% of subjects with single-VRI not involving LAD, 16.5% of those with multi-VRI involving LAD, and 7.3% of patients with multi-VRI not involving LAD (overall P < .001). Even at incremental multivariable Cox proportional analysis, hierarchical VRI was independently associated with an increased risk of D/MI [hazard ratio = 1.17 (1.04-1.08) for each class increment, P = .010].

Conclusions

Location and extent of myocardial ischemia at MPS according to the VRI concept have a hierarchical predictive impact, with multi-VRI involving LAD being significantly and independently more prognostically ominous than other types of VRI.
  相似文献   
56.
57.
Vascular endothelial growth factor (VEGF) is a potent stimulator of angiogenesis, associated with unfavorable clinical characteristics in breast cancer. The aim of this study was to evaluate different angiogenic markers in endocrine-positive breast cancer patients. The authors analyzed serum and tumor samples from 71 patients with endocrine-positive operable primary breast cancer to determine the expression and the possible relationship between circulating serum VEGF levels, tumor VEGF expression, microvessel density (MVD), and other immunohistochemical parameters. Basal VEGF serum levels were significantly higher in breast cancer patients than in healthy controls. A significant correlation was observed between basal VEGF serum concentrations, microvessel density (p = 0.01) and p53 status (p = 0.004). Intratumoral VEGF expression was significantly associated with neoplastic embolization (p = 0.041) and circulating VEGF levels (p = 0.047). The results confirm that in primary endocrine-positive breast cancer serum VEGF levels are elevated and show a positive relationship with tumor VEGF and p53 overexpression.  相似文献   
58.
The aim of this investigation is to evaluate the role of bone photonic densitometry in uremic osteodystrophy. Bone mineral content (BMC) and bone density (BD) have been measured in 80 hemodialyzed patients by double photonic emission densitometry. Photonic densitometry shows an higher sensibility to quantitative changes in bone mineral content than metacarpal index (IM). Photonic densitometry is unable to differentiate osteoporosis from osteomalacia; this differential diagnosis can be obtained by radiological analysis: low BD and low IM means osteoporosis, low BD and resorptive changes in cortical bone means osteomalacia and/or hyperparathyroidism. Photonic densitometry is particularly suitable for uremic osteodystrophy follow-up because of its easy repetitiveness and innocuousness and for its close correlation with iPTH variations.  相似文献   
59.
The NM23 gene and its expression in oral squamous cell carcinoma.   总被引:7,自引:0,他引:7  
The murine nm23, a putative metastasis suppressor, has three human homologues, NM23-H1, -H2, and -H3b. Several reports have suggested a low metastatic potential for neoplasms with a high expression of NM23-H1 gene, while other studies have not shown this relationship. These apparent differences in the role of NM23 in metastasis suppression might be explained by unability to discriminate between the expression of the two genes NM23-H1 and NM23-H2. The NM23-H2 product is not related to tumor progression and metastasis suppression. Two studies on human oral squamous cell carcinoma (OSCC) have been reported, both showing the NM23 product to be a metastasis suppressor factor. However, none of these two studies distinguished NM23-H1 from NM23-H2. The aim of this study was to detect the protein expression pattern of NM23-H1 product in 24 OSCCs by immunohistochemistry in paraffin-embedded tissues using a monoclonal antibody non-cross-reactive with NM23-H2. The NM23-H1 positive group showed lower frequency of lymph node metastasis, and a better grading than the NM23-H1 negative group supporting the role of NM23-H1 as metastasis suppressor factor which may be useful for predicting tumor metastasis in OSCC.  相似文献   
60.
The favourable safety profile and ubiquitous nature of melatonin has led to an increase in its use in various clinical settings in adults and children. We performed a systematic review of published studies on the use of melatonin for anaesthetic indications in paediatric patients. To identify relevant articles, PubMed, EMBASE, Cumulative Index to Nursing and Allied Health Literature, Web of Science and Scopus databases were searched. Study title and abstract screening, and full text review were performed by two reviewers. Twenty-seven eligible studies investigating melatonin use for anaesthetic indications were identified. Due to significant heterogeneity in study methodology, a quantitative synthesis of the published findings was not possible. The identified studies were therefore categorised by the indication for melatonin: analgesia, diagnostic sedation and as an anaesthetic adjunct. Melatonin use for anaesthetic-related indications is safe; may provide analgesia for inflammatory-associated pain in neonates and children before venepuncture; may decrease the need for, or replace, general anaesthesia for diagnostic procedures; and may serve as an anaesthesia adjunct before induction in paediatric patients.  相似文献   
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