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Restless legs syndrome (RLS) is a common neurological disorder of a primary unpleasant sensation with an urge to move the legs occurring at rest. The etiology of idiopathic RLS is unknown and structural cerebral abnormalities have so far not been detected. We studied 51 right-handed patients with an idiopathic restless legs syndrome in two independent samples (Regensburg RLS-group: n = 28, Munich RLS-group: n = 23) and compared them to 51 sex- and age-matched healthy volunteers. High-resolution T1-weighted magnetic resonance imaging (MRI) of each subject was obtained and analyzed using voxel-based morphometry (VBM) to detect regionally specific differences in gray matter between patients and controls. Conjunction analysis was used to combine results from both centers. In patients with idiopathic RLS, both study centers observed independently a bilateral gray matter increase in the pulvinar. In the conjunction analysis including all patients and controls from both study centers, a significant gray matter increase in the pulvinar bilaterally (right: x = 16, y = -21, z = 12, Z = 4.57; left: x = -16, y = -24, z = 12, Z = 4.10) was present. This is the first demonstration of structural changes in the brain of patients with idiopathic RLS. These changes in thalamic structures are either involved in the pathogenesis of RLS or may reflect a consequence of chronic increase in afferent input of behaviorally relevant information.  相似文献   
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STUDY OBJECTIVES: Community-acquired pneumonia (CAP) is a widespread disease with important implications for health-care systems worldwide. This study investigated direct costs, treatment patterns, and outcomes associated with two patient cohorts hospitalized with CAP. DESIGN: The study design was naturalistic, prospective, and open. PATIENTS: The study enrolled 580 patients. Two hundred sixty-one patients were treated initially with IV moxifloxacin (45%, cohort M); the remaining 319 patients received nonstandardized treatment (cohort S). SETTING: Twenty-two hospitals in Germany. RESULTS: Clinical success rates were similar between treatment groups (cohort M, 242 of 256 patients, 95%; cohort S, 286 of 312 patients, 92%; p = 0.208). Mean +/- SD length of hospital stay was 10.8 +/- 5.2 days, with cohort M having a significantly shorter hospital stay (10.0 +/- 4 days) compared to cohort S (11.5 +/- 6 days; p < 0.001). Median of all direct costs was dollar 1,333 (minimum, dollar 127; maximum, dollar 9,488), with direct costs of dollar 1,250 in cohort M (minimum, dollar 372; maximum, dollar 9,488) and dollar 1,409 in cohort S (minimum, dollar 127; maximum, dollar 9,366) per treated episode of CAP (p = 0.066). CONCLUSIONS: Major determinants of costs were length of hospital stay and ICU admission, whereas costs for staff and hotel were major contributors to direct costs. Initial antibiotic therapy with moxifloxacin resulted in similar clinical efficacy and direct costs compared to nonstandardized therapy; however, patients treated with moxifloxacin benefited with an earlier hospital discharge.  相似文献   
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The goal of this study was to investigate the effect of plasma treatment on the wettability and dissolution of fenofibrate compacts. Contact angle measurements and intrinsic dissolution rate studies of untreated and plasma-treated fenofibrate compacts were conducted. The contact angle data clearly show that the wettability of the tablet surface increased with the duration of plasma treatment.Analyses of stability revealed that the surfaces which were plasma-treated for more than 1 min regained some degree of hydrophobicity after storage in air. Since their hydrophobic recovery finally reached the level observed with 1 min plasma-treated fenofibrate compacts it was deduced that permanent incorporation of hydrophilic groups had already attained saturation upon plasma irradiation for 1 min.Dissolution studies revealed the advantages of the hydrophilized surface of plasma-treated fenofibrate compacts. Due to the improved wettability of plasma-treated fenofibrate its intrinsic dissolution rate was vastly increased compared to untreated fenofibrate. This study thus demonstrates the potential of plasma treatment to enhance the wettability and dissolution behavior of poorly water-soluble drugs.  相似文献   
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Mogler C, Herold‐Mende C, Dyckhoff G, Jenetzky E, Beckhove P & Helmke B M
(2011) Histopathology  58 , 944–952
Heparanase expression in head and neck squamous cell carcinomas is associated with reduced proliferation and improved survival Aims: Cellular expression of heparanase, a degrading enzyme of the extracellular matrix, is associated with poorer prognosis in several cancers. The present analysis, has studied the role of heparanase in tumour growth and clinical outcome in patients with head and neck squamous cell carcinoma (HNSCC). Methods and Results: We analysed the cellular expression of the active form of heparanase in 71 human HNSCCs, using immunohistochemistry. The results were compared with clinicopathological data and, in 65 cases with immunoreactivity for the proliferation marker, MIB1. Cellular heparanase expression was detected in 41 of 71 (57.74%) cases; in particular, UICC IV‐stage tumours showed high heparanase levels. Heparanase was localized mainly in the cytoplasm and, to a lesser extent, at the cell membrane. High levels of heparanase were significantly correlated with an almost four‐fold decrease in MIB1 labelling (P = 0.006). Comparison with clinical outcome by multivariate analysis revealed that patients with high‐level heparanase expression had prolonged overall survival (P = 0.029). Conclusions: Although heparanase was mainly found in late‐stage HNSCCs, cellular heparanase expression in HNSCCs was associated with prolonged overall survival. We propose that the proliferation‐reducing effect of high heparanase levels might outweigh the tumour‐promoting effects of heparanase, especially in advanced tumours.  相似文献   
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We know much about how rats use their whiskers to discriminate simple tactile properties, but little about how they are used in natural settings. Here we studied whisker motion during social interactions between rats in order to gain a better understanding of natural whisker use in this model system for sensorimotor integration. In the first set of experiments, an intruder was placed in a second rat's home cage. Anogenital sniffing immediately ensued; later in the trial, facial interactions occurred at least as frequently. Whereas much previous work has focused on the importance of anogenital sniffing during social interactions, these facial interactions were accompanied by some of the most intense whisker behaviors described to date. Whisker trimming increased biting but reduced boxing. In addition, whiskers were more protracted and whisking amplitude was larger in aggressive than in nonaggressive interactions. In a second set of experiments, rats interacted facially across a gap. As rats approached each other, whisking amplitude decreased and whiskers were more protracted. Whisker trimming disrupted facial alignment and reduced the frequency of interactions, indicating that whisker use, and possibly whisker protraction, is important for rats to orient themselves with respect to one another. We also found that females whisked with smaller amplitude when interacting with males than with females, and that they held their whiskers less protracted than males. The natural whisker use described here should further our understanding of this important somatosensory system during social interactions.  相似文献   
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Ependymomas generally arise in the central nervous system (CNS). Rare primary extraneural ependymomas have been observed. Here, we describe the first case of an overt malignant primary extraneural ependymoma in a young female patient. Careful reevaluation together with extensive review of the literature and comparison of related cases established the diagnosis after treatment failure and tumor progression. The tumor was large and firm with some small cysts and showed pseudorosettes with strong glial fibrillary acidic protein (GFAP) expression. In conclusion, primary extraneural ependymomas have to be included into the differential diagnosis of abdominal tumors with pseudorosette-formation, even in unusual sites, and GFAP-immunohistochemistry (IHC) supports the diagnosis.  相似文献   
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