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MA Suckow SL Voytik-Harbin LA Terril SF Badylak 《Journal of investigative surgery》2013,26(5):277-287
Small instestinal submucosa (SIS) is an easily produced material that has been used experimentally for tissue engineering. To evaluate the ability of SIS to facilitate bone growth within a long-bone defect, a segment of the radius was surgically removed in adult, female Sprague-Dawley rats. The defect was either left unfilled or implanted with SIS, demineralized cortical bone (DMCB), or ovalbumin. The defect was evaluated radiographically and histologically after 3, 6, 12, and 24 weeks. Tissue remodeling within the defect was evident by week 3 in SIS- and DMCB-treated rats. Filling was characterized initially by infiltration of mononuclear cells and extracellular material in SIS-implanted rats and multifocal remodeling bone particles and cartilage formation in DMCB implanted rats. Cartilage was observed as early as 3 weeks and bone as early as 6 weeks in SIS-implanted rats. Filling of the defect arose from multiple foci in DMCB-implanted rats, but was contiguous with and parallel to the ulnar shaft in SIS-implanted rats, suggesting that defect repair by SIS may be conductive rather than inductive. Rats in which the defect was left unfilled demonstrated slow but progressive filling of the defect, characterized by mononuclear cell infiltrates and fibrous extracellular material. In summary, SIS facilitated rapid filling of a longbone defect. These results suggest that SIS may be useful as a bone repair material. 相似文献
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Cherie Paquette Mark F. Evans Shabnum S. Meer Vanitha Rajendran Christine S-C. Adamson Kumarasen Cooper 《Head and neck pathology》2013,7(4):361-372
Human papillomavirus (HPV) infection, most commonly genotype 16 of the alpha-9 family, is implicated in the etiology of a subset of oropharyngeal squamous cell carcinomas (OPSC) worldwide. Data are scarce regarding OPSC in South Africans, and three prior studies suggest no significant etiologic role for HPV. We aimed to investigate for evidence of HPV etiology in OPSCs from black South Africans by polymerase chain reaction (PCR) methodologies with determination of HPV subtype by sequencing, in situ hybridization (ISH), and p16INK4a immunohistochemistry (IHC), as a surrogate marker for an HPV-driven tumor. It was hypothesized that HPV-driven tumors would be positive by PCR plus IHC and/or ISH whereas OPSCs with HPV background infections (HPV-passenger) would be positive by PCR alone. Formalin-fixed, paraffin-embedded tissues from 51 OPSCs collected between 2005 and 2010 from 41 patients were analyzed for HPV by GP5+6+ PCR (targeting the HPV L1 region), pU-1M/pU-2R PCR (targeting the HPV E6/E7 region) and HPV-31 specific PCR (targeting the E5 region), chromogenic ISH, and p16INK4a IHC. All cases positive by PCR were subject to sequencing to determine HPV genotype. The patient mean age was 58.0 years and 88 % were male. Of the 51 evaluable tumors, 48 (94.1 %) were positive for HPV DNA by PCR: 25 (49.1 %) met criteria for an HPV-driven tumor, 23 (45.1 %) for HPV-passenger, and 3 (5.9 %) were HPV-unrelated. Sequencing of the PCR-positive cases revealed the following genotypes: combined HPV-16 and 31 (41.7 %), HPV-31 (25.0 %), HPV-16 (22.9 %), combined HPV-16 and 18 (6.3 %), and a single case each of HPV 18 and HPV 33. Studies via ISH were negative in all cases. In accordance with worldwide trends but contrary to prior South African data, HPV likely plays an etiologic role in a significant subset (at least 49.1 %) of OPSC in black South Africans. We found that the alpha-9 HPV family, particularly HPV-16 and 31 either in combination or separately, to predominate in our sample tumors. The use of multiple PCR primers increased sensitivity of viral detection, and a HPV-31 specific primer confirmed the presence of this genotype in many samples. Further studies including HPV E6/E7 mRNA assays are needed to better elucidate the pathogenic role of HPV in black South African OPSCs. 相似文献
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Ranjith Babu Peter G. Kranz Isaac O. Karikari Allan H. Friedman Cory Adamson 《Journal of clinical neuroscience》2013,20(10):1382-1386
Adult brainstem gliomas (BSG) are uncommon tumors that constitute only 2% of all brain tumors. Due to its rare occurrence in the elderly (60 years and older), there is no literature discussing the natural history, prognosis, and best treatment strategy for malignant BSG in this population to our knowledge. We report seven elderly patients with malignant BSG and propose treatment strategies to manage these aggressive tumors. The median age at onset in this cohort was 65 years, with the majority of patients being male (71.4%) and Caucasian (85.7%). The median duration of symptoms prior to presentation was 0.5 months, with the most common symptoms being facial weakness, blurry vision, headache, and extremity weakness. Tumors were most commonly located in the pons (85.7%), with one tumor being located in the tectal plate. Five of seven (71.4%) patients underwent biopsies, with two patients undergoing partial resections. Following tissue diagnosis, patients received radiation therapy and concurrent temozolomide, followed by additional chemotherapeutics upon progression. Side effects as a result of treatment were seen in three patients and all involved reversible hematological complications such as neutropenia and thrombopenia. The median time to progression was 6.7 months and the median overall survival was 13.5 months. While malignant BSG in elderly patients are aggressive gliomas with an overall poor prognosis, these patients are able to safely undergo aggressive chemoradiotherapy, resulting in improved survival. Resection may be considered for select patients in which the tumor is mostly exophytic, near the brainstem surface, and easily accessible. 相似文献
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Salomone Erica Settanni Michele McConachie Helen Suma Katharine Ferrara Federica Foletti Giulia Salandin Arianna Servili Chiara Adamson Lauren B. 《Journal of autism and developmental disorders》2022,52(10):4286-4300
Journal of Autism and Developmental Disorders - Parents of children with ASD (N?=?86; mean age 44.8 months; 67 boys) were randomized to either WHO Caregiver Skills Training... 相似文献
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Nuno?Mendon?aEmail authorView authors OrcID profile Antoneta?Granic John?C.?Mathers Tom?R.?Hill Mario?Siervo Ashley?J.?Adamson Carol?Jagger 《European journal of nutrition》2018,57(8):2713-2722
Purpose
The very old (aged ≥ 85 years), fastest growing age group in most western societies, are at especially high risk of muscle mass and strength loss. The amount, sources and timing of protein intake may play important roles in the aetiology and management of sarcopenia. This study investigated the prevalence and determinants of low protein intake in 722 very old adults participating in the Newcastle 85+ Study.Methods
Protein intake was estimated with 2 × 24-h multiple pass recalls (24 h-MPR) and contribution (%) of food groups to protein intake was calculated. Low protein intake was defined as intake < 0.8 g of protein per adjusted body weight per day. A backward stepwise multivariate linear regression model was used to explore socioeconomic, health and lifestyle predictors of protein intake.Results
Twenty-eight percent (n = 199) of the community-living very old in the Newcastle 85+ Study had low protein intake. Low protein intake was less likely when participants had a higher percent contribution of meat and meat products to total protein intake (OR 0.97, 95% CI 0.95, 1.00) but more likely with a higher percent contribution of cereal and cereal products and non-alcoholic beverages. Morning eating occasions contributed more to total protein intake in the low than in the adequate protein intake group (p < 0.001). Being a woman (p < 0.001), having higher energy intake (p < 0.001) and higher tooth count (p = 0.047) was associated with higher protein intake in adjusted models.Conclusion
This study provides novel evidence on the prevalence of low protein intake, diurnal protein intake patterns and food group contributors to protein intake in the very old.89.
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