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61.
Despite the many studies documenting cerebral white matter microstructural alterations associated with very preterm birth (<32 weeks’ gestation), there is a dearth of similar research in moderate and late preterm infants (born 32–36 weeks’ gestation), who experience higher rates of neurodevelopmental delays than infants born at term (≥37 weeks’ gestation). We therefore aimed to determine whether whole brain white matter microstructure differs between moderate and late preterm infants and term-born controls at term-equivalent age, as well as to identify potential perinatal risk factors for white matter microstructural alterations in moderate and late preterm infants. Whole brain white matter microstructure was studied in 193 moderate and late preterm infants and 83 controls at term-equivalent age by performing Tract-Based Spatial Statistics analysis of diffusion tensor imaging data. Moderate and late preterm infants had lower fractional anisotropy and higher mean, axial and radial diffusivities compared with controls in nearly 70 % of the brain’s major white matter fiber tracts. In the moderate and late preterm group, being born small for gestational age and male sex were associated with lower fractional anisotropy, largely within the optic radiation, corpus callosum and corona radiata. In conclusion, moderate and late preterm infants exhibit widespread brain white matter microstructural alterations compared with controls at term-equivalent age, in patterns consistent with delayed or disrupted white matter microstructural development. These findings may underpin some of the neurodevelopmental delays observed in moderate and late preterm children.  相似文献   
62.
Gout,diet, and the insulin resistance syndrome   总被引:5,自引:0,他引:5  
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63.
64.
Early detection of bladder cancer and its recurrences is essential for improved prognosis and long-term survival. The detection and follow-up of these patients is currently based on cystoscopy, which is expensive and invasive, and, in most cases, cytology, which is non-invasive but not very sensitive. During recent years, many urine-based tests have been developed and tested in different patient populations. In this review we discuss new developments for biomarkers in bladder cancer that have potential use in surveillance and screening. In almost all publications authors compare sensitivity of the test with a concomitantly executed cystoscopy, for example, determine cross-sectional sensitivity. However, it has also been shown that false positive test results may be followed by a positive cystoscopy in the near future, showing that cystoscopy itself does not provide 100% sensitivity. This suggests that for a proper evaluation of urine-based tests, longitudinal studies should be carried out and the results communicated to the urologist.  相似文献   
65.
Radio Immuno Guided Surgery (RIGS) is a technique that has numerous uses in oncology. It is characterised by a multidisciplinary approach by nuclear physician and surgeon for diagnosis and treatment; it uses colloid radiotracers, monoclonal antibodies or non-immunological tracers. We adopted this technique in 281 patients: 256 (91.9%) (range 26-82) with breast disease (breast cancer or occult breast lesions) and 25 (8.9%) (range 42-84) with colorectal cancer localized or recurrent. We used monoclonal antibodies (ArcitumoMab 99mTc-labelled) for colorectal carcinomas and aggregates of human serum albumin 99mTc-labelled for Radioguided Occult Lesion Localization (ROLL) and Sentinel Lymph-Node Biopsy (SLNB). All patients were studied preoperatively by routine blood tests, instrumental exams and tumoral markers. Amongst patients with breast disease, 142 breast cancers and 114 occult breast lesions were found. Among patients with colorectal disease, 8 cases had localized colorectal cancer and 17 cases had locoregional recurrence and/or metastasis. In all cases pathologic sites were detected by probe during surgery. The RIGS is indicated for ROLL and SLNB; nevertheless it is also suggested for pre- and intraoperatively staging of primary and recurrent colorectal cancers. This method gives a chance for a radical surgical and oncologic treatment in localized and recurrent cancer. Prospective studies are needed in order to estimate survival and usefulness of this methodology.  相似文献   
66.
Ectopic breast tissue occurs in 0.4-6% of the general population. Usually, these tissues develop along the embryonic milk line but other sites are reported in the literature. Accessory breasts are commonly axillary and may undergo hormonal changes. Some pathologies of normally positioned breasts can occur in ectopic breast tissue, including carcinoma, and therefore require traditional senological flow-charts and imaging strategies. Supernumerary nipples are generally asymptomatic but may sometimes be associated with urological malformations. In our 10-year experience, 208 patients were observed (138 polythelia and 70 polymastia) and 159 surgical procedures were performed, 97 for supernumerary nipple excision and 67 for accessory breast ablation. Five neoplastic lesions and 25 fibrocystic mastopathies were detected in specimens; normal nipple or breast tissue was found in 129. In view of the potentially malignant transformation of accessory breasts, thorough physician evaluation is needed. Surgery is currently suggested in cases of suspected malignancy, in symptomatic cases and for cosmetic problems.  相似文献   
67.
The active resolution of inflammation is recognized as offering new opportunities to generate novel anti-inflammatory agents. The emerging appreciation of the importance of active resolution in regulation of inflammation also creates an imperative to examine developing and existing agents for their potential to influence these pathways. This themed issue of the British Journal of Pharmacology contains papers that discuss the roles of annexin-1, lipoxins and related lipid products of fish oils as well as other mechanisms involved in active resolution and their receptor targets.This article is part of a themed issue on Mediators and Receptors in the Resolution of Inflammation. To view this issue visit http://www3.interscience.wiley.com/journal/121548564/issueyear?year=2009  相似文献   
68.

Background and purpose:

In the mammalian brain, histaminergic neurotransmission is mediated by the postsynaptic histamine H1 and H2 receptors and the presynaptic H3 autoreceptor, which also acts as a heteroreceptor. The H1 receptor has been implicated in spatial learning and memory formation. However, pharmacological and lesion studies have revealed conflicting results. To examine the involvement of histamine H1 receptor in spatial reference and working memory formation, H1 receptor knockout mice (KO) were tested in the eight-arm radial maze. Previously, we found that the H1 receptor-KO mice showed reduced emotionality when confronted with spatial novelty. As it is known that emotions can have an impact on spatial learning and memory performance, we also evaluated H1 receptor-KO mice in terms of emotional behaviour in the light–dark box.

Experimental approach:

Mice lacking the H1 receptor and wild-type mice (WT) were tested for spatial reference and working memory in an eight-arm radial maze with three arms baited and one trial per day. Emotional behaviour was measured using the light–dark test.

Key results:

The H1 receptor-KO mice showed impaired spatial reference and working memory in the radial maze task. No significant differences between H1 receptor-KO and WT mice were observed in the light–dark test.

Conclusions and implications:

The spatial memory deficits of the H1 receptor-KO mice might be due to the reported changes in cholinergic neurochemical parameters in the frontal cortex and the CA1 subregion of the hippocampus, to impaired synaptic plasticity in the hippocampus, and/or to a dysfunctional brain reward/reinforcement system.  相似文献   
69.

Background

To correlate the metabolic changes with size changes for tumor response by concomitant PET-CT evaluation of lung cancers after radiotherapy.

Methods

36 patients were studied pre- and post-radiotherapy with18FDG PET-CT scans at a median interval of 71 days. All of the patients were followed clinically and radiographically after a mean period of 342 days for assessment of local control or failure rates. Change in size (sum of maximum orthogonal diameters) was correlated with that of maximum standard uptake value (SUV) of the primary lung cancer before and after conventional radiotherapy.

Results

There was a significant reduction in both SUV and size of the primary cancer after radiotherapy (p < 0.00005). Among the 20 surviving patients, the sensitivity, specificity, and accuracy using PET (SUV) were 94%, 50%, 90% respectively and the corresponding values using and CT (size criteria) were 67%, 50%, and 65% respectively. The metabolic change (SUV) was highly correlated with the change in size by a quadratic function. In addition, the mean percentage metabolic change was significantly larger than that of size change (62.3 ± 32.7% vs 47.1 ± 26.1% respectively, p = 0.03)

Conclusion

Correlating and incorporating metabolic change by PET into size change by concomitant CT is more sensitive in assessing therapeutic response than CT alone.  相似文献   
70.
Ohne Zusammenfassung  相似文献   
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