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61.
BACKGROUND AND PURPOSE:Peripheral nerve disorders caused by benign and malignant primary nerve sheath tumors, infiltration or compression of nerves by metastatic disease, and postradiation neuritis demonstrate overlapping features on conventional MR imaging but require vastly different therapeutic approaches. We characterize and compare diffusivities of peripheral nerve lesions in patients undergoing MR neurography for peripheral neuropathy or brachial or lumbosacral plexopathy.MATERIALS AND METHODS:Twenty-three patients, referred for MR neurography at our institution between 2003 and 2009 for a peripheral mononeuropathy or brachial or lumbosacral plexopathy and whose examinations included DWI, received a definitive diagnosis, based on biopsy results or clinical and imaging follow-up, for a masslike or infiltrative peripheral nerve or plexus lesion suspicious for tumor. Mean ADC values were determined within each lesion and compared across 3 groups (benign lesions, malignant lesions, and postradiation changes).RESULTS:Both ANOVA and Kruskal-Wallis tests demonstrated a statistically significant difference in ADC values across the 3 groups (P = .000023, P = .00056, respectively). Post hoc pair-wise comparisons showed that the ADC within malignant tumors differed significantly from that within benign tumors and postradiation changes. ADC within benign tumors and postradiation changes did not differ significantly from each other.CONCLUSIONS:DWI may be highly effective for the differentiation of benign from malignant peripheral nerve masslike or infiltrative lesions.

Peripheral neuropathies can be divided into mononeuropathies, polyneuropathies, and plexopathies. Patients present with pain, sensory symptoms, and/or motor deficits in the distribution of a single peripheral nerve, multiple peripheral nerves, or a nerve plexus. Mononeuropathies affect a single peripheral nerve. Polyneuropathies affect multiple peripheral nerves. In plexopathies, symptoms are localized to the brachial or lumbosacral plexus.Polyneuropathies are generally attributable to systemic diseases (eg, diabetes and vitamin deficiencies), while mononeuropathies are most often due to trauma, nerve compression syndromes that occur at a few characteristic anatomic locations, or mass lesions. History and physical examination, supplemented in a subset of cases by laboratory studies, electrodiagnostic studies, and neuroimaging, are the main tools for diagnostic evaluation. In patients with a classic compression mononeuropathy, such as median nerve compression at the carpal tunnel, the diagnosis can often be made clinically and corroborated by needle electromyography, nerve conduction, and/or imaging studies.14 For mononeuropathies involving nerves not typically susceptible to compression syndromes, imaging can play an essential role in identifying the lesion and guiding management.Plexopathies give rise to motor and/or sensory deficits in an extremity. Most brachial plexopathies (75%) are attributable to postradiation changes, primary and metastatic lung cancer, or metastatic breast cancer.5 Common causes of lumbosacral plexopathy are primary and metastatic tumor, including cervical, endometrial, ovarian, prostate, testicular, and colorectal cancer; postradiation changes; and diabetes.6 For patients with a history of radiation for malignancy, recurrent tumor with nerve invasion must be distinguished from radiation plexopathy; both can develop months to years following therapy and can have similar clinical presentations.6Although benign and malignant primary nerve sheath tumors, infiltration of nerves by metastatic disease, and postradiation neuritis require different therapeutic approaches, they also demonstrate overlapping features on MR imaging, including T2 hyperintensity, focal enlargement, and enhancement.7,8 Diffusivity measurements from DWI may be helpful in differentiating distinct pathologic entities. In prior studies, DWI was useful in differentiating malignant and benign peripheral nerve sheath tumors,9 retroperitoneal masses,10 head and neck tumors,11,12 and lymph nodes.13,14 Other studies have demonstrated differences in the diffusivities of adult15 or pediatric brain tumors16 that correlate with tumor grade and/or histologic type. In this study, we focus on masslike or infiltrative lesions of the peripheral nerves detected by MR imaging in patients presenting clinically with a peripheral mononeuropathy or plexopathy. We characterize and compare the diffusivities of these lesions and demonstrate significant differences among benign and malignant peripheral nerve tumors and postradiation changes.  相似文献   
62.
Response to treatment with selective serotonin reuptake inhibitors (SSRIs) varies considerably between patients. The International SSRI Pharmacogenomics Consortium (ISPC) was formed with the primary goal of identifying genetic variation that may contribute to response to SSRI treatment of major depressive disorder. A genome-wide association study of 4-week treatment outcomes, measured using the 17-item Hamilton Rating Scale for Depression (HRSD-17), was performed using data from 865 subjects from seven sites. The primary outcomes were percent change in HRSD-17 score and response, defined as at least 50% reduction in HRSD-17. Data from two prior studies, the Pharmacogenomics Research Network Antidepressant Medication Pharmacogenomics Study (PGRN-AMPS) and the Sequenced Treatment Alternatives to Relieve Depression (STAR*D) study, were used for replication, and a meta-analysis of the three studies was performed (N=2394). Although many top association signals in the ISPC analysis map to interesting candidate genes, none were significant at the genome-wide level and the associations were not replicated using PGRN-AMPS and STAR*D data. Top association results in the meta-analysis of response included single-nucleotide polymorphisms (SNPs) in the HPRTP4 (hypoxanthine phosphoribosyltransferase pseudogene 4)/VSTM5 (V-set and transmembrane domain containing 5) region, which approached genome-wide significance (P=5.03E−08) and SNPs 5'' upstream of the neuregulin-1 gene, NRG1 (P=1.20E−06). NRG1 is involved in many aspects of brain development, including neuronal maturation and variations in this gene have been shown to be associated with increased risk for mental disorders, particularly schizophrenia. Replication and functional studies of these findings are warranted.  相似文献   
63.
Objective To clarify the long-term renal prognosis and related risk factors of progression for IgA nephropathy (IgAN) patients who achieved remission under current therapy. To identify the target value of the serum albumin level for Chinese patients with IgAN. Methods The patients with biopsy-proven primary IgAN in Nephrology Department of Renji Hospital in Shanghai were studied.The survival of renal and the relationships between clinical parameters and renal outcome were assessed. Results A total of 369 patients between Jan 2005 and Dec 2010 were included with a median follow-up time of 49.0 (38.0-65.8) months. All the subjects had achieved a complete remission (CR) or partial remission (PR) following six months’ therapy after diagnosis. Progressive renal disease had occurred in 61 cases at the end of follow-up. Three variables had a significant independent effect on renal outcome in patients achieving remission under current therapy regimen for IgAN, including time-average serum creatinine (TA-Scr) [HR(95%CI): 1.03(1.01-1.04)], time-average serum albumin (TA-Alb) [HR(95%CI): 0.83 (0.69-0.99)], and eGFR ratio within one year [HR(95%CI): 0.00(0.00-0.01)]. By multivariate Cox analyses, each 1 g/L drop of TA-Alb was related with 17.2% increase in the risk of renal progression. The ROC curve indicated that combination of serum albumin at baseline and during a long-term had a more significant value in prediction of renal outcome than independent predictor alone. By Kaplan-Meier analyses, patients with TA-Alb﹤38 g/L had a 10.4 fold sincreased risk of progressive disease compared with that of TA-Alb﹥38 g/L. Conclusions IgAN patients with lower eGFR ratio, higher TA-Scr and lower TA-Alb would progress to ESRD more quickly, and serum albumin during follow-up is important for predicting IgAN progression.  相似文献   
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65.
Considerable confusion exists regarding the proper classification of idiopathic eosinophilic pneumonia (IEP). In addition, there are no reports that reveal clinicopathological differences between the various eosinophilic pneumonias. A problem persists in describing what the essential histological differences are between the different types of IEP. In this context, we examined the histological findings of acute eosinophilic pneumonia (AEP) and chronic eosinophilic pneumonia (CEP) and contrasted them with the clinical features and radiological findings. Radiologically, ground glass opacity and interlobular septal thickening were characteristic of the AEP cases studied, while air space consolidation was seen in all CEP cases. Histologically, interstitial edema and fibrin deposition were prominent in the AEP cases. Type II cells were detached from the alveolar walls, though the basal lamina was predominantly intact. In CEP, in addition to cellular infiltration, there was prominent intraluminal fibrosis. Disruption of the basal lamina was observed and nests of intraluminal fibrosis were directly adjacent and connected to the alveolar walls. From these findings, we conclude that the histological differences between AEP and CEP are the severity of basal lamina damage, the amount of subsequent intraluminal fibrosis, and the severity of interstitial edema. Especially in AEP, interstitial edema is an essential histological finding and this finding explains the acute onset, and the radiographic findings, as well as the rapid and complete improvement noted in such cases.  相似文献   
66.
Background: In addition to releasing a pool of growth factors during activation, platelets have many features that indicate their role in the anti‐infective host defense. The antimicrobial activities of platelet‐rich plasma (PRP) and related plasma preparations against periodontal disease–associated bacteria were evaluated. Methods: Four distinct plasma fractions were extracted in the formulation used commonly in dentistry and were tested for their antibacterial properties against three periodontal bacteria: Porphyromonas gingivalis, Aggregatibacter actinomycetemcomitans, and Fusobacterium nucleatum. The minimum inhibitory concentration of each plasma preparation was determined, and in vitro time‐kill assays were used to detect their abilities to inhibit bacterial growth. Bacterial adhesion interference and the susceptibility of bacterial adherence by these plasma preparations were also conducted. Results: All plasma preparations can inhibit bacterial growth, with PRP showing the superior activity. Bacterial growth inhibition by PRP occurred in the first 24 hours after application in the time‐kill assay. PRP interfered with P. gingivalis and A. actinomycetemcomitans attachment and enhanced exfoliation of attached P. gingivalis but had no influences on F. nucleatum bacterial adherence. Conclusions: PRP expressed antibacterial properties, which may be attributed to platelets possessing additional antimicrobial molecules. The application of PRP on periodontal surgical sites is advisable because of its regenerative potential and its antibacterial effects.  相似文献   
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Green tea is a widely consumed beverage known for its beneficial anti-inflammatory, anti-oxidative, anti-mutagenic, anti-carcinogenic, and cardioprotective properties. Here, we administered epigallocatechin gallate fraction of green tea extract (EGTE) to mice for 6 weeks and examined the effects on the innate and adaptive immune responses by measuring phagocytic and natural killer (NK) cell activity, as well as antigen-specific proliferation, cytolysis, cytokine secretion, and antibody production. Our data show that EGTE administration increased NK cell cytolysis and peritoneal cell phagocytosis, as well as splenocyte proliferation and secretion of IL-2 and IFN-γ. Of note, EGTE treatment decreased the production antigen-specific IgE via increased the proportion of CD4+ CD25+ regulatory T lymphocytes in the spleen, suggesting that EGTE may play a role in regulating the allergic response.  相似文献   
70.
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