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31.
Y Baba  S Iwao  Y Kodama 《Journal of UOEH》1983,5(3):351-358
Serial spirograms of 121 dust workers whose chest X-rays were found to be "class 1" of the diagnostic criteria for pneumoconiosis were obtained during 1978-80. Yearly changes of pulmonary function variables (%VC, FEV1, FEV1/FVC%,V25/H, and V50/V25) by age, smoking habit, total years of exposure to dust, and work history were evaluated. The average age of the dust workers was 48.0 +/- 5.5 years, and the average years of exposure to dust was 21.6 +/- 6.8 years in 1978. Eighty-two dust workers smoked with the mean smoking history of 24.7 pack-years. No significant differences of spirograms were found between the smoking and non-smoking groups. Among the smokers, however, linear regression of FEV1/FVC% by age gradually decreased during 1978-80. All the pulmonary function variables showed no correlation with smoking history as well as total years of dust exposure. All the dust workers were classified into eight types of work by their histories; crushing and quarrying operators, brick mason, foundry and grinding operators, asbestos workers, underground miners, refractory material workers, pyrites roasters, and welders. The underground miners showed lower FEV1/FVC% and V25 than the average. However, the difference of such pulmonary function variables by eight types of work was not significant by analysis of variance. Since aging is the most dominant factor for pulmonary dysfunction, a longer observation on this group will be needed.  相似文献   
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Contention exists on the development of pneumatization of temporal bone. Many techniques to measure the volume of pneumatization have been reported, but no techniques for direct surface area measurement. We measured the surface area and volume of human mastoid air cells. Eight normal temporal bones removed at autopsy were analyzed and fixed in formalin fixative, decalcified, and embedded in celloidin, sectioned at 25 microns and stained with H-E for histological examination. Total surface area and the volume of human mastoid air cells were measured using a personal computer. The surface area of pneumatic spaces for the 8 temporal bone specimens ranged from 36.1 cm2 to 163.0 cm2 (mean +/- SD: 89.1 +/- 34.0 cm2). The volume of pneumatic spaces for the 8 specimens ranged from 1.53 ml to 6.03 ml (mean +/- SD: 4.12 +/- 0.97 ml). The surface area of temporal bone pneumatic spaces we determined could serve as useful basic data for determining the physiology of ventilation for the temporal bone and the function of mastoid cells.  相似文献   
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In almost every type of artificial valve, structural failure has been described. We are reporting on a case of a sudden leaflet escape of an Edwards TEKNA mitral valve prosthesis 12 years after implantation. The patient had a sudden onset of dyspnea and severe pulmonary edema with subsequent cardiogenic shock. An emergency mitral replacement was successfully performed. A multi-detector computed tomography scanning and three-dimensional imaging showed two fragments that had embolized in the terminal aorta and the left common iliac artery. The patient presented visual field abnormality, and postoperative head computed tomography showed watershed cerebral infarction. The escaped leaflet that fractured transversely was removed, following the patient’s recovery, during cardiac surgery.  相似文献   
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Nivolumab and pembrolizumab are humanized IgG4 monoclonal antibodies against programmed cell death 1 (PD-1). Although these agents are effective in treating advanced melanoma, non-small-cell lung carcinoma, and other types of cancers, various adverse events have been reported. Cutaneous adverse events are particularly prevalent and, while granulomatous/sarcoid-like reactions are uncommon, they are increasingly recognized as immune-related adverse events associated with immune checkpoint inhibitors. Herein, we report two cases of granulomatous/sarcoid-like reaction with foreign material, mimicking metastatic malignancy after PD-1 inhibitor treatment. Clinicians should be aware of the existence of cutaneous lesions and perform biopsy if needed to prevent misdiagnosis and unnecessary adjustments to immunotherapy.  相似文献   
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This randomized double-blind crossover study aimed to investigate the influence of cytochrome P450 (CYP) 2C19 polymorphisms on the antiplatelet effects of prasugrel in patients with non-cardioembolic stroke treated with clopidogrel. Patients received clopidogrel 75 mg/day for >?4 weeks. Subsequently, patients received prasugrel 3.75 mg/day (group A; n?=?64) or 2.5 mg/day (group B; n?=?65) for 4 weeks followed by a 4 week switched-dose regimen. To assess the influence of CYP2C19 polymorphisms, patients were classified as extensive metabolizers (EMs), intermediate metabolizers (IMs), and poor metabolizers (PMs). The primary endpoint was P2Y12 reaction units (PRU) at the end of each 4 week treatment. A significant reduction in PRU was noted after treatment with prasugrel 3.75 mg/day compared with the pre-dose value (after treatment with clopidogrel) (p?<?0.0001). By CYP2C19 phenotypes, a significant reduction in PRU was noted in IMs and PMs after treatment with prasugrel 3.75 mg/day and in PMs after treatment with prasugrel 2.5 mg/day, as compared with the pre-dose value (p?<?0.0001). The plasma concentration of the active metabolite of clopidogrel was relatively low in PMs compared to EMs and IMs; prasugrel was similar across all CYP2C19 phenotypes. No major or clinically significant hemorrhagic adverse events occurred. By CYP2C19 phenotype, the antiplatelet effects of prasugrel were greater with 3.75 mg/day in IMs and PMs, and with 2.5 mg/day in PMs compared with clopidogrel 75 mg/day, without safety concerns. CYP2C19 polymorphisms did not affect the plasma concentration of the active metabolite of prasugrel or its antiplatelet effects. (JapicCTI-101044).  相似文献   
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OBJECTIVE: Angiotensin-converting enzyme (ACE) inhibitor and angiotensin II type I receptor blockers (ARB) prevent cardiac remodeling after myocardial infarction (MI). However, it is controversial whether combination therapy of ACE inhibitor and ARB is more effective on cardiac remodeling than each agent alone. In this study, we compared the effects of an ACE inhibitor (temocapril), an ARB (CS-866), and their combination on cardiac remodeling after MI. METHODS: Temocapril at 3 or 30 mg/kg/day, CS-866 at 1 or 10 mg/kg/day, or combined temocapril and CS-866 at 1.5 and 0.5 mg/kg/day or at 15 and 5 mg/kg/day, respectively, were administered to rats after MI. At 4 weeks after MI, we assessed hemodynamics, cardiac function by Doppler echocardiography and non-infarcted myocardial mRNA expression. RESULTS: Animals treated with a combination of the two drugs had hemodynamics, heart weights and dimensions similar to the other treated animals. However, the combination of the two drugs suppressed ANP, BNP and other gene expressions related to contractile proteins of fetal type and collagens more effectively than ACE inhibitor or ARB alone. CONCLUSION: These data suggest that combination of the two drugs, independent of the hemodynamic effect, may improve left ventricular phenotypic change, collagen accumulation and diastolic function.  相似文献   
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Rationale:In coronavirus disease 2019 (COVID-19) patients with acute respiratory distress syndrome refractory to optimal conventional management, we should consider the indication for veno-venous extracorporeal membrane oxygenation (V-V ECMO). Growing evidence indicates that COVID-19 frequently causes coagulopathy, presenting as hypercoagulation and incidental thrombosis. For these reasons, a multifactorial approach with several anticoagulant markers should be considered in the management of anticoagulation using heparin in COVID-19 patients on V-V ECMO.Patient concerns:A 48-year-old man was infected with COVID-19 with a worsening condition manifesting as acute respiratory distress syndrome.Diagnoses:He was refractory to conventional therapy, thus we decided to introduce V-V ECMO. We used heparin as an anticoagulant therapy for V-V ECMO and adjusted the doses of heparin by careful monitoring of the activated clotting time (ACT) and activated partial thromboplastin time (APTT) to avoid both hemorrhagic and thrombotic complications. We controlled the doses of heparin in the therapeutic ranges of ACT and APTT, but clinical hemorrhaging and profound elevation of coagulant marker became apparent.Interventions:Using thromboelastography (TEG; Haemonetics) in addition to ACT and APTT, we were able to clearly detect not only sufficient coagulability of COVID19 on V-V ECMO (citrated rapid thromboelastography-R 0.5 min, angle 75.5°, MA 64.0 mm, citrated functional fibrinogen-MA 20.7 mm) but also an excessive effect of heparin (citrated kaolin -R 42.7 min, citrated kaolin with heparinase 11.7 min).Outcomes:Given the TEG findings indicating an excessive heparin effect, the early withdrawal of ECMO was considered. After an evaluation of the patient''s respiratory capacity, withdrawal from V-V ECMO was achieved and then anticoagulation was stopped. The hemorrhagic complications and elevated thrombotic marker levels dramatically decreased.Lessons:TEG monitoring might be a useful option for managing anticoagulation in COVID-19 patients on V-V ECMO frequently showing a hypercoagulative state and requiring massive doses of heparin, to reduce both hemorrhagic and thrombotic complications.  相似文献   
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