全文获取类型
收费全文 | 3907篇 |
免费 | 194篇 |
国内免费 | 37篇 |
专业分类
耳鼻咽喉 | 117篇 |
儿科学 | 60篇 |
妇产科学 | 75篇 |
基础医学 | 420篇 |
口腔科学 | 90篇 |
临床医学 | 259篇 |
内科学 | 1011篇 |
皮肤病学 | 79篇 |
神经病学 | 314篇 |
特种医学 | 186篇 |
外科学 | 724篇 |
综合类 | 48篇 |
预防医学 | 119篇 |
眼科学 | 40篇 |
药学 | 292篇 |
中国医学 | 17篇 |
肿瘤学 | 287篇 |
出版年
2023年 | 41篇 |
2022年 | 61篇 |
2021年 | 95篇 |
2020年 | 72篇 |
2019年 | 78篇 |
2018年 | 76篇 |
2017年 | 54篇 |
2016年 | 79篇 |
2015年 | 86篇 |
2014年 | 104篇 |
2013年 | 148篇 |
2012年 | 179篇 |
2011年 | 180篇 |
2010年 | 104篇 |
2009年 | 75篇 |
2008年 | 133篇 |
2007年 | 159篇 |
2006年 | 143篇 |
2005年 | 150篇 |
2004年 | 137篇 |
2003年 | 140篇 |
2002年 | 177篇 |
2001年 | 129篇 |
2000年 | 125篇 |
1999年 | 123篇 |
1998年 | 61篇 |
1997年 | 40篇 |
1996年 | 27篇 |
1995年 | 42篇 |
1994年 | 31篇 |
1993年 | 30篇 |
1992年 | 106篇 |
1991年 | 78篇 |
1990年 | 87篇 |
1989年 | 65篇 |
1988年 | 87篇 |
1987年 | 64篇 |
1986年 | 72篇 |
1985年 | 60篇 |
1984年 | 51篇 |
1983年 | 49篇 |
1981年 | 20篇 |
1979年 | 38篇 |
1978年 | 23篇 |
1977年 | 23篇 |
1974年 | 21篇 |
1972年 | 20篇 |
1971年 | 24篇 |
1968年 | 21篇 |
1966年 | 21篇 |
排序方式: 共有4138条查询结果,搜索用时 0 毫秒
81.
82.
83.
84.
To assess the effects of imposition of moderate diabetes on in vivo cardiac performance in gradually proceeding hypertension, spontaneously hypertensive (SHR) and Wistar-Kyoto rats (WKY) were treated with streptozotocin (40 mg/kg) or vehicle at 8 weeks of age. Four and 20 weeks later, with the rats under ether anesthesia, peak cardiac output and stroke volume were measured during volume loading and peak left ventricular developed pressure and maximum rate of rise of pressure (dP/dtmax) were determined during aortic occlusion. Additionally, passive pressure-volume relations were obtained during saline infusion in potassium-arrested hearts, and the chamber stiffness constant was derived from one exponential function. There was a mortality of 16.1% in the diabetic SHR only. While basal and stressed cardiac performance was unchanged despite the already decreased mean arterial pressure and left ventricular weight at 4 weeks, the diabetic SHR revealed significant decreases in peak cardiac pumping indexes, peak left ventricular developed pressure, and dP/dtmax, with unchanged resting cardiac function, at 20 weeks. Changes seen in the diabetic WKY were reduced left ventricular weight at 4 weeks and reduced peak left ventricular dP/dtmax at 20 weeks. The chamber stiffness was unaltered with strain or diabetes. These data show that imposition of even moderate diabetes substantially influences the stress-loaded in vivo cardiac performance in the SHR, whereas it produces only minor changes in the WKY. 相似文献
85.
Iwamoto T Kimura A Nakai T Kanaya K Ishimaru S 《Journal of atherosclerosis and thrombosis》2004,11(6):348-353
The pathophysiology of aortic aneurysm is complex and it has remained unclear how frequently arteriomegaly, a diffuse dilatation of the artery, is associated with aneurysm. Therefore, ultrasonic study of the carotid artery was conducted to clarify this issue in a large number of subjects. Carotid ultrasonography was performed in 1,108 Japanese men aged 50 or older, and the results of 379 patients with arteriosclerotic aortic aneurysm (AA) were compared with those of 211 patients with peripheral arterial disease, 65 patients with aortic dissection, 232 hypertensive subjects, and 221 normotensive subjects. The carotid diameter was measured bilaterally at two points on the common carotid artery, and we defined carotid arteriomegaly as an arterial diameter in the 95th percentile or above that in the normotensive control group according to the relevant age subgroups. The incidence of carotid arteriomegaly in the AA group (25.9%) was significantly higher than in the other groups (p < 0.01) even when adjusted for body height and blood pressure. In the arteriomegaly subgroup, hypertension and cigarette smoking was significantly more frequent than in the non-dilated artery subgroup. This study demonstrates that one fourth of patients with aortic aneurysm have arteriomegaly as a generalized systemic abnormality in the arterial wall. 相似文献
86.
S Tsubosaka F Sasaki S Ameshima H Takahashi Y Kishi T Ishizaki T Nakai S Miyabo Y Imamura Y Fukuda 《Kekkaku : [Tuberculosis]》1992,67(11):721-728
We had a sixty-five year old male patient who suddenly complained of dyspnea and fever with pulmonary tuberculosis, severe respiratory failure, disseminated intravascular coagulation (DIC) and intractable bilateral pneumothoraces. From the first hospital day severe hypoxemia which did not respond to conventional oxygen therapy developed with a diffuse ill-defined reticulo-nodular shadow in the plain chest x-ray film. On the 2nd hospital day mechanical ventilation with 2cmH2O PEEP was introduced. Antituberculous agents as well as corticosteroids were started suspecting acute interstitial pneumonia with pulmonary tuberculosis and adult respiratory distress syndrome (ARDS). Medication was followed by the treatment of Gabexate mesilate and heparin against DIC on laboratory data. Though clinical findings and pulmonary infiltrate on chest x-ray film transiently improved, right pneumothorax occurred suddenly on the 6th day followed with left pneumothorax on the 36th day. Tube drainage of both pleural spaces and repeated instillation of thrombin-rich oxycel cotton via bronchofiberscope failed to stop air leakage. He ultimately expired on 49th hospital day. At postmortem lung had multiple bilateral bulla several of which ruptured to the pleural site and caseating necrotic area containing bacilli positively stained with Ziehl-Nielsen stain in the bilateral upper lobe. No typical caseating necrotic lesion, however, was found in the other lung tissue. Therefore, it seemed to show a chronic phase of diffuse alveolar damage (DAD). 相似文献
87.
Seiki Kamisue Midori Shima Takuya Nishimura Ichiro Tanaka Hiroaki Nakai Shogo Morichika Noboru Takata Atsushi Kuramoto Akira Yoshioka 《British journal of haematology》1994,86(1):106-111
We have established an ELISA for detecting thrombin cleavage of the FVIII light chain at Arg1689 . The method used a coating alloantibody which recognized amino acid residues 2248–2312 in the C2 domain, together with a second monoclonal antibody, NMC-VIII/10, which recognized residues 1675–1684 in the amino-terminal region of the light chain. FVIII antigen (FVIII:Ag) was measured after treatment of plasma with various concentrations of thrombin. The FVIII:Ag of normal plasma was reduced in a dose-dependent manner by the thrombin, falling to 28% in the presence of 100 U/ml enzyme. The concentration of thrombin that achieved 50% reduction (IC50 ) was approximately 1·0 U/ml. The plasma of four haemophilia A positive (A+ ) and two haemophilia A reduced (AR ) patients were analysed. The IC50 of all patients was more than 1·0 U/ml, indicating that thrombin cleavage of the FVIII light chain was defective. One haemophilia A+ plasma did not respond to thrombin in this ELISA system. The patient (TI) was a haemophiliac with FVIII coagulant activity of 0·04 U/ml and FVIII:Ag of 1·78 U/ml. In addition, immunoblotting of the purified FVIII from TI showed that thrombin cleavage of the 80 kilodalton (kD) light chain was impaired. The patient's DNA was amplified using the polymerase chain reaction with a set of synthetic oligonucleotide primers spanning amino acid residues 1646–1714. Sequence analysis of the amplified DNA fragments revealed a cytosine to thymine transition, converting an arginine 1689 to cysteine. This abnormal FVIII was designated as FVIII Hiroshima. Our ELISA system is a simple and useful method of evaluating the proteolytic cleavage by thrombin at Arg1689 . 相似文献
88.
Masatoshi Katagiri Hiroyuki Ito Yasuo Murayama Megumi Hamada Syunji Nakajima Nobuya Takayanagi Ai Uemiya Mitsunori Myogan Akio Nakai Masatsugu Tsujii 《Brain & development》2021,43(5):605-615
BackgroundDifficulties in fine and gross motor skills are often overlooked as developmental problems, although approximately 6–13% of all school-age children have poor motor coordination. Understanding motor coordination is important from the perspective of school adaptation. This longitudinal cohort study aimed to determine whether fine and gross motor skills in preschool children predict later academic achievement and psychosocial maladaptation.Methods & ProceduresParticipants were 2,501 children from nursery and elementary schools (5–13 years old). The motor skills of preschool children were assessed by their nursery teacher immediately before entering elementary school. The Strengths and Difficulties Questionnaire and a standardized Japanese test were administered annually throughout elementary school.ResultsEarly motor difficulties in preschool children had significant effects on their academic achievement and psychosocial maladaptation up until the sixth grade. Gross motor difficulties in preschool were associated with the later peer problems and worsened emotional symptoms.ConclusionsMotor skills in preschool children are useful as a predictor of later psychosocial maladaptation and academic achievement. 相似文献
89.
Muhammad Farooq Hiroyuki Nakai Atsushi Fujimoto Hiroki Fujikawa Asako Matsuyama Naoyuki Kariya Atsuko Aizawa Hiroshi Fujiwara Masaaki Ito Yutaka Shimomura 《Human mutation》2013,34(1):176-183
Generalized pustular psoriasis (GPP) is a rare, potentially life threatening, and aggressive form of psoriasis, which is characterized by sudden onset with repeated episodic skin inflammation leading to pustule formation. Familial GPP is known to be caused by recessively inherited mutations in the IL36RN gene, which encodes interleukin 36 receptor antagonist (IL‐36Ra). In this article, we performed mutation analysis of the IL36RN gene in 14 Japanese patients with GPP, and identified mutations in two of these patients analyzed. One patient was compound heterozygous for mutations c.115+6T>C and c.368C>G (p.Thr123Arg), whereas the other carried compound heterozygous mutations c.28C>T (p.Arg10*) and c.115+6T>C in the IL36RN gene. Expression studies using total RNA from the patients’ skin revealed that the mutation c.115+6T>C resulted in skipping of exon 3, leading to a frameshift and a premature termination codon (p.Arg10Argfs*1). The protein structure analysis suggested that the missense mutation p.Thr123Arg caused misfolding and instability of IL‐36Ra protein. In vitro studies in cultured cells showed impaired expression of the p.Thr123Arg mutant IL‐36Ra protein, which failed to antagonize the IL‐36 signaling pathway. Our data further underscore the critical role of IL36RN in pathogenesis of GPP. 相似文献
90.
Clinical outcome of endoscopic aspiration mucosectomy for early stage gastric cancer 总被引:10,自引:0,他引:10
Tanabe S Koizumi W Mitomi H Nakai H Murakami S Nagaba S Kida M Oida M Saigenji K 《Gastrointestinal endoscopy》2002,56(5):708-713
BACKGROUND: Endoscopic mucosal resection is an established treatment option for early stage gastric cancer. However, several problems with endoscopic mucosal resection remain to be solved, such as appropriate treatment for recurrence and incomplete tumor resection. The outcome for patients undergoing endoscopic aspiration mucosectomy (endoscopic mucosal resection) by a modification of the cap-fitted technique was evaluated retrospectively to determine factors associated with complete resection and tumor recurrence. METHODS: Endoscopic mucosal resection was performed in 106 patients with early stage gastric cancers up to 20 mm in diameter that were well or moderately differentiated adenocarcinoma. All were superficial lesions without ulceration, distinct signs of submucosal invasion, or a poorly demarcated border. En bloc (tumors <10 mm in diameter) or piecemeal (tumors 10-20 mm in diameter) resection was performed. Follow-up endoscopy was performed at 2, 6, 12, 18, and 24 months and thereafter once per year. Outcome and factors associated with complete resection and tumor recurrence were assessed retrospectively. RESULTS: Sixty-eight patients (64%) underwent en bloc resection and 38 (36%) piecemeal resection. The mean longest dimension (SD) of the resected lesions was significantly greater after piecemeal resection (12.3 [4.0] mm) than after en bloc resection (7.6 [4.0] mm; p < 0.01). In patients with tumors completely resected, there was no recurrence after either en bloc or piecemeal resection. Six of 8 patients found to have submucosal invasion after endoscopic mucosal resection underwent surgery. Patients with incompletely resected intramucosal lesions underwent additional endoscopic treatment. Cancer recurred in 3 patients (2.8%), all of whom had lesions measuring more than 15 mm in diameter. CONCLUSIONS: Endoscopic mucosal resection is safe and useful for the management of early stage gastric cancer. Further improvement in outcome requires more accurate preoperative diagnosis and postoperative histopathologic evaluation. Patients with incompletely resected lesions should undergo aggressive additional treatment. 相似文献