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81.
Cetinkaya BO Keles GC Ayas B Aydin O Kirtiloglu T Acikgoz G 《Clinical oral investigations》2007,11(1):61-68
Guided tissue regeneration is based on preventing the more rapidly proliferating epithelium from growing into the periodontal
defect after surgical procedures incorporating barrier membranes. The aim of this study was to compare the proliferative activity
of gingival epithelium using proliferating cell nuclear antigen (PCNA) as a marker of cell proliferation after surgical treatments
with bioactive glass graft material and bioabsorbable membrane. Using split mouth design, 20 intrabony defects were randomly
assigned treatments with bioactive glass (BG group) or bioabsorbable membrane (BM group). Gingival biopsies were taken at
preoperative and postoperative 12 weeks. After histological processing, the number of the inflammatory cells was measured
in hematoxylin and eosin-stained sections; PCNA expression was determined in immunohistochemically-stained sections. At postoperative
12 weeks, the number of the inflammatory cells was significantly decreased (p < 0.01), PCNA expression was significantly increased (p < 0.001) in both treatment groups compared to baseline data. There was no significant difference in PCNA expression between
baseline values of two groups (p > 0.05), while at postoperative 12 weeks, increase in BG group was significantly greater than that in BM group (p < 0.001). These results suggest that epithelial cell proliferation is more prominent after treatment of intrabony defects
with bioactive glass compared to the treatment with bioabsorbable membrane. 相似文献
82.
β‐adrenergic Receptor Blocker ICI 118,551 Selectively Increases Intermediate‐Conductance Calcium‐Activated Potassium Channel (IKCa)‐Mediated Relaxations in Rat Main Mesenteric Artery 下载免费PDF全文
Endothelial IKCa and/or SKCa channels play an important role in the control of vascular tone by participating in endothelium‐dependent relaxation. Whether β‐AR antagonists, mainly used in hypertension, affect endothelial KCa channel function is unknown. In this study, we examined the effect of the β2‐AR antagonist and inverse agonist ICI 118,551 on the IKCa/SKCa channel activity by assessing functional relaxation responses to several agonists that stimulate these channels. Mesenteric arterial rings isolated from male Sprague Dawley mounted to organ baths. Acetylcholine elicited IKCa‐ and SKCa‐mediated relaxations that were abolished by TRAM‐34 and apamin, respectively. ICI 118,551, which did not dilate the arteries per se, increased the IKCa‐mediated relaxations, whereas SKCa‐mediated relaxations remained unaltered. Same potentiating effect was also detected on the IKCa‐mediated relaxations to carbachol and A23187, but not to NS309. Neither acetylcholine‐induced nitric oxide‐mediated relaxations nor SNP relaxations changed with ICI 118,551. The PKA inhibitor KT‐5720, the selective β2‐AR agonist salbutamol, the selective β2‐AR antagonist butoxamine, the non‐selective β‐AR antagonist propranolol, and the inverse agonists carvedilol or nadolol failed to affect the IKCa‐mediated relaxations. ICI 118,551‐induced increase was not reversed by salbutamol or propranolol as well. Besides, low potassium‐induced relaxations in endothelium‐removed arteries remained the same in the presence of ICI 118,551. These data demonstrate a previously unrecognized action of ICI 118,551, the ability to potentiate endothelial IKCa channel‐mediated vasodilation, through a mechanism independent of β2‐AR antagonistic or inverse agonistic action. Instead, the enhancement of acetylcholine relaxation seems likely to occur by a mechanism secondary to endothelial calcium increase. 相似文献
83.
Acar Baver Kose Ozkan Unal Melih Turan Adil Kati Yusuf Alper Guler Ferhat 《European journal of orthopaedic surgery & traumatology : orthopedie traumatologie》2020,30(1):163-173
European Journal of Orthopaedic Surgery & Traumatology - This retrospective study aimed to compare the clinical and radiological outcomes of patients who underwent biplane chevron medial... 相似文献
84.
Ahmet Guner MD Zubeyde Bayram MD Murat B. Rabus MD Semih Kalkan MD Hicaz Z. Aguş MD Mehmet Ozkan MD 《Journal of cardiac surgery》2020,35(2):422-424
Cardiac myxomas (CM) is by far the most common type of primary cardiac neoplasm that commonly arise within the left atria and is composed of primitive connective tissue cells and stroma. Despite the benign nature, the CMs are often surgically removed because they can lead to severe complications. Large, thin, and hypermobile forms are unusual. The frequency of recurrence is about 22% for complex forms and 12% for other familial forms and 1% to 3% for sporadic myxomas, which seldom recur after surgery. Although transesophageal echocardiography shows usually accurate imaging capabilities to detect the myxoma, further imaging methods including computed tomography, cardiovascular magnetic resonance imaging, and 18F-fluorodeoxyglucose positron-emission tomography/computed tomography may be useful to diagnosis for it. Surgery is the mainstay of treatment 相似文献
85.
Coronary artery thromboembolism: Unexpected presentation of left atrial myxoma covered with thrombus
Samet Uysal MD Ayse Zehra Karakoc MD Kadir Biyikli MD Benay Erden MD Ozkan Candan MD Gonca Gul Gecmen MD 《Journal of cardiac surgery》2020,35(8):2097-2099
Cardiac myxomas are benign primer cardiac tumors of the heart. They can be fatal with a thromboembolic presentation. Myocardial infarction is one of these unusual thromboembolic presentations. We report a patient who presented with cardiac arrest due to ventricular fibrillation related to myocardial infarction. After successful resuscitation, coronary angiography and transthoracic echocardiography were performed. A left atrial mass was observed and interpreted as a possible cause of coronary embolism leading to myocardial infarction. After surgical excision, the pathological examination confirmed myxoma, which was the essential cause of the tendency to arterial embolism. 相似文献
86.
Acute respiratory distress syndrome (ARDS) is a real challenge for the pulmonary and critical care physicians. Although it is quite frequently encountered in intensive care clinics, its diagnosis and treatment bare many variations among the clinicians. Since ARDS is a fully dynamic process, there is no uniform application of mechanical ventilation (MV) being one of the inevitable components of ARDS management. This situation makes the clinicians very prone to make mistakes during setting and subsequent adjustments of mechanical ventilation parameters. In this review, we aimed to clarify the most common issues of discussion by presenting the principles of MV in ARDS with regard to some recent modifications. 相似文献
87.
The utility of serum receptor-binding cancer antigen expressed on SiSo cells in gastrointestinal tract cancers. 总被引:2,自引:0,他引:2
Sahin Coban Hasan Ozkan Seyfettin K?klü Osman Yüksel Muhammed Cem Ko?kar Tarik Akar Necati Ormeci 《Journal canadien de gastroenterologie》2006,20(9):593-596
BACKGROUND: Receptor-binding cancer antigen expressed on SiSo cells (RCAS1) is a novel tumour marker that has been described in various kinds of cancer. The majority of observations include immunohistochemical studies; however, there are not enough data about the utility of this antigen as a serum tumour marker and its tumour specificity. AIM: To measure the serum levels of RCAS1 in patients with gastrointestinal (GI) tract cancers and compare them with other GI tract tumour markers. PATIENTS AND METHODS: Sera collected from patients with GI cancers (14 esophagus, 32 gastric and 36 colon) and from healthy volunteers (30 individuals) were analyzed for RCAS1 and compared with carcinoembryonic antigen (CEA) and cancer antigen 19-9. The relationship between serum RCAS1, tumour stage and tumour grade was also evaluated. RESULTS: Mean serum RCAS1 level was higher in patients with GI tract cancers compared with the control group (P=0.001). Among GI tract cancers, RCAS1 had lowest and highest sensitivity for esophagus and colon cancer diagnosis, respectively. Serum RCAS1 had a higher sensitivity for malignancy, except in the colon, and lower specificity in all groups compared with CEA. In comparison with cancer antigen 19-9, serum RCAS1 was more sensitive but less specific for all GI cancer groups. Mean serum RCAS1 levels were not statistically significant among histopathological tumour types (P>0.05). Although serum RCAS1 levels were significantly higher in cases with lymph node involvement compared with lymph node-negative cases (P=0.009), there was no difference between cases with and without serosal involvement, vascular invasion and distant metastasis; no correlation was found between tumour size and RCAS1 levels. CONCLUSIONS: RCAS1 may be used and combined with CEA as a tumour marker in GI tract cancers. 相似文献
88.
OBJECTIVE: Surgical treatment of rheumatic valvular disease still constitutes a significant number of cardiac operations in developing countries. Despite improvements in myocardial protection and cardiopulmonary bypass techniques, triple valve operations (aortic, mitral and tricuspid valves) are still challenging because of longer duration of cardiopulmonary bypass and higher degree of myocardial decompensation. This study was instituted in order to assess results of triple valve surgery. METHODS: Between 1977 and 2002, 34 patients underwent triple valve surgery in our clinic by the same surgeon (EB). Eleven patients underwent triple valve replacement (32.4%) and 23 underwent tricuspid valve annuloplasty with aortic and mitral valve replacements (67.6%). RESULTS: There was no significant difference between the two groups of patients who underwent triple valve replacement and aortic and mitral valve replacement with tricuspid valve annuloplasty. There were 4 hospital deaths (11.8%) occurring within 30 days. The duration of follow-up for 30 survivors ranged from 6 to 202 months (mean 97 months). The actuarial survival rates were 85%, 72%, and 48% at 5, 10, and 15 years respectively. Actuarial freedom from reoperation rates at 5, 10, and 15 years was 86.3%, 71.9%, and 51.2%, respectively. Freedom from cerebral thromboembolism and anticoagulation-related hemorrhage rates, expressed in actuarial terms was 75.9% and 62.9% at 5 and 10 years. Major cerebral complications occurred in 10 of the 30 patients. CONCLUSION: We prefer replacing, if repairing is not possible, the tricuspid valve, with a bileaflet mechanical prosthesis in a patient with valve replacement of the left heart who will be anticoagulated in order to avoid unfavorable properties of bioprosthesis like degeneration and of old generation mechanical prosthesis like thrombosis and poor hemodynamic function. In recent years, results of triple valve surgery either with tricuspid valve conservation or valve replacement in suitable cases have become encouraging with improvements in surgical techniques and myocardial preservation methods. 相似文献
89.
90.