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141.
142.
Sang Joon Kim Choong Gon Choi Jeong Kon Kim Sung-Cheol Yun Geon-Ho Jahng Ha-Kyu Jeong Eun Ju Kim 《Korean journal of radiology》2015,16(2):297-303
Objective
To validate the usefulness of a diffusional anisotropic capillary array phantom and to investigate the effects of diffusion tensor imaging (DTI) parameter changes on diffusion fractional anisotropy (FA) and apparent diffusion coefficient (ADC) using the phantom.Materials and Methods
Diffusion tensor imaging of a capillary array phantom was performed with imaging parameter changes, including voxel size, number of sensitivity encoding (SENSE) factor, echo time (TE), number of signal acquisitions, b-value, and number of diffusion gradient directions (NDGD), one-at-a-time in a stepwise-incremental fashion. We repeated the entire series of DTI scans thrice. The coefficients of variation (CoV) were evaluated for FA and ADC, and the correlation between each MR imaging parameter and the corresponding FA and ADC was evaluated using Spearman''s correlation analysis.Results
The capillary array phantom CoVs of FA and ADC were 7.1% and 2.4%, respectively. There were significant correlations between FA and SENSE factor, TE, b-value, and NDGD, as well as significant correlations between ADC and SENSE factor, TE, and b-value.Conclusion
A capillary array phantom enables repeated measurements of FA and ADC. Both FA and ADC can vary when certain parameters are changed during diffusion experiments. We suggest that the capillary array phantom can be used for quality control in longitudinal or multicenter clinical studies. 相似文献143.
Manoel de Jesus Moura Júnior Antonio Luís Martins Maia Filho Diego Rodrigues Pessoa Marcos Danilo Rodrigues Alves Jefferson de Sousa Justino Matheus dos Santos Andrade Ana Maria Gonçalves Rebêlo Carlos José de Lima Antonio Luiz Barbosa Pinheiro Landulfo Silveira Jr. 《Lasers in medical science》2015,30(6):1729-1738
144.
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146.
Hyun Jang Sang Hoon Kim Sang Hag Park Il Han Choo Seung Gon Kim 《Psychiatry investigation》2015,12(2):274-277
A 16-year-old woman was referred to us for depression and persistent suicidal and homicidal ideation. From 2010, the patient visited a neurologist due to recurrent grand mal epilepsy, auditory and visual hallucinations, episodic memory loss, and persistent depression. Upon admission, it was revealed through clinical history taking that she had suffered from chronic bullying from same-sex peers and sexual abuse, twice, from an adult male in the neighborhood when she was 10 years old. A brain magnetic resonance imaging study showed left mesial hippocampal sclerosis. The patient exhibited improvement of her psychiatric symptoms after treatment with a combination of fluoxetine (30 mg) and aripiprazole (10 mg). Children and adolescents with epilepsy experience conflicts in the family, challenges at school, stigma, and psychosocial limitations or deprivations due to their comorbid psychiatric symptoms and hence, psychiatric evaluation and early intervention is important when treating these patients. 相似文献
147.
Jeong Hoon Kim Tack Geun Cho Jae Gon Moon Chang Hyun Kim Ho Kook Lee 《Journal of Korean Neurosurgical Society》2015,58(4):373-378
ObjectiveTo determine the advantages of parietal approach compared to Kocher''s point approach for spontaneous, oval-shaped intracerebral hemorrhage (ICH) with expansion to the parietal region.MethodsWe divided patients into two groups : group A had burr holes in the parietal bone and group B had burr holes at Kocher''s point. The hematoma volume, Glasgow coma scale (GCS) score, and modified Barthel Index (mBI) score were calculated. At discharge, we evaluated the patients'' Glasgow outcome scale (GOS) score, modified Rankin Scale (mRS) score, motor grade, and hospitalization duration. We evaluated the patients'' mBI scores and motor grades at 6 months after surgery.ResultsThe hematoma volume in group A was significantly less than that in group B on postoperative days 1, 3, 5, 7, 14, and 21. Group A had significantly higher GCS scores than did group B on postoperative days 1 and 3. Group A had higher mBI scores postoperatively than did group B, but the scores were not significantly different. No differences were observed for the GOS score, mRS score, motor grade at discharge, or duration of hospitalization. The mBI score of group A at 6 months after surgery was significantly higher, and more patients in group A showed muscle strength improvement.ConclusionIn oval-shaped ICH with expansion to the parietal region, the parietal approach is considered to improve the clinical symptoms at the acute phase by removing the hematoma more effectively in the early stages. The parietal approach might help promote the long-term recovery of motor power. 相似文献
148.
Ortenberg R Gon S Porat A Beckwith J 《Proceedings of the National Academy of Sciences of the United States of America》2004,101(19):7439-7444
A strain of Escherichia coli missing three members of the thioredoxin superfamily, thioredoxins 1 and 2 and glutaredoxin 1, is unable to grow, a phenotype presumed to be due to the inability of cells to reduce the essential enzyme ribonucleotide reductase. Two classes of mutations can restore growth to such a strain. First, we have isolated a collection of mutations in the gene for the protein glutaredoxin 3 that suppress the growth defect. Remarkably, all eight independent mutations alter the same amino acid, methionine-43, changing it to valine, isoleucine, or leucine. From the position of the amino acid changes and their effects, we propose that these alterations change the protein so that its properties are closer to those of glutaredoxin 1. The second means of suppressing the growth defects of the multiply mutant strain was by mutations in the DNA replication genes, dnaA and dnaN. These mutations substantially increase the expression of ribonucleotide reductase, most likely by altering the interaction of the regulatory protein DnaA with the ribonucleotide reductase promoter. Our results suggest that this increase in the concentration of ribonucleotide reductase in the cell allows more effective interaction with glutaredoxin 3, thus restoring an effective pool of deoxyribonucleotides. Our studies present direct evidence that ribonucleotide reductase is the only essential enzyme that requires the three reductive proteins missing in our strains. Our results also suggest an unexpected regulatory interaction between the DnaA and DnaN proteins. 相似文献
149.
Hiroshi Mukae Takeshi Kaneko Yasushi Obase Masaharu Shinkai Toshio Katsunuma Kiyoshi Takeyama Jiro Terada Akio Niimi Hiroto Matsuse Kazuhiro Yatera Yoshihiro Yamamoto Arata Azuma Hirokazu Arakawa Takashi Iwanaga Haruhiko Ogawa Kiyoyasu Kurahashi Yasuhiro Gon Hirokazu Sakamoto Jun Tamaoki 《Respiratory investigation》2021,59(3):270-290
Cough and sputum are common complaints at outpatient visits. In this digest version, we provide a general overview of these two symptoms and discuss the management of acute (up to three weeks) and prolonged/chronic cough (longer than three weeks). Flowcharts are provided, along with a step-by-step explanation of their diagnosis and management. Most cases of acute cough are due to an infection. In chronic respiratory illness, a cough could be a symptom of a respiratory infection such as pulmonary tuberculosis, malignancy such as a pulmonary tumor, asthma, chronic obstructive pulmonary disease, chronic bronchitis, bronchiectasis, drug-induced lung injury, heart failure, nasal sinus disease, sinobronchial syndrome, eosinophilic sinusitis, cough variant asthma (CVA), atopic cough, chronic laryngeal allergy, gastroesophageal reflux (GER), and post-infectious cough. Antibiotics should not be prescribed for over-peak cough but can be considered for atypical infections. The exploration of a single/major cause is recommended for persistent/chronic cough. When sputum is present, a sputum smear/culture (general bacteria, mycobacteria), cytology, cell differentiation, chest computed tomography (CT), and sinus X-ray or CT should be performed. There are two types of rhinosinusitis. Conventional sinusitis and eosinophilic rhinosinusitis present primarily with neutrophilic inflammation and eosinophilic inflammation, respectively. The most common causes of dry cough include CVA, atopic cough/laryngeal allergy (chronic), GER, and post-infectious cough. In the last chapter, future challenges and perspectives are discussed. We hope that the clarification of the pathology of cough hypersensitivity syndrome will lead to further development of “pathology-specific non-specific therapeutic drugs” and provide benefits to patients with chronic refractory cough. 相似文献
150.
Taizo Furukawa Shigeyoshi Aoi Kohei Sakai Mayumi Higashi Shigehisa Fumino Tatsuro Tajiri 《Asian journal of endoscopic surgery》2015,8(4):473-476
Omental lipoblastoma is extremely rare among benign tumors. We herein report the case of a child who underwent laparoscopic extirpation of a large omental lipoblastoma. A 4‐year‐old girl was diagnosed with an intra‐abdominal solid tumor. Abdominal imaging revealed a fat density mass that was well encapsulated and measured 18 × 15 × 7.5 cm in size. Considering the MRI findings and movability of the tumor, we strongly suspected that the lesion was an omental lipoblastoma. We initially decided to perform laparoscopic exploration and, if possible, extirpation of the solid tumor sequentially. A total of five trocars were used, and the tumor was found to originate from the omentum. We successfully performed complete resection of the tumor laparoscopically. A histological examination revealed lipoblastoma. For large abdominal tumors in children, the laparoscopic approach is recommended as the first procedure when the tumor is preoperatively considered to be benign and resectable. 相似文献