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11.
Clinical diabetic nephropathy in man is the consequence of the development of a specific constellation of glomerular, tubular, vascular, and interstitial structural abnormalities accompanied by highly characteristic immunohistochemical alterations that, together, are unique to diabetes. Because changes resembling the specific pathology of diabetes do not develop in patients with conditions that lead to long-standing glomerular hyperfunction (such as unilateral nephrectomy), it is unlikely that glomerular hemodynamic abnormalities per se can be the cause of diabetic nephropathy. Whether hemodynamic abnormalities represent a risk factor that, in the presence of the diabetic state, can accelerate the rate of development of the basic lesions of diabetic nephropathy is currently unclear. However, there is considerable evidence that when the renal lesions of diabetes are far advanced, factors such as systemic hypertension can determine the rate of renal functional deterioration in diabetes as in other disorders. Although the diabetic rat may be a useful model for the study of aspects of the pathogenesis of diabetic nephropathy, much confusion has resulted from the inclusion of focal segmental glomerular sclerosis as a diabetic lesion. Similarly, the acceptance of all increases in urinary protein excretions in this model as resulting from or reflecting of diabetic nephropathology can be misleading. It is concluded that treatment aimed at manipulating renal hemodynamics in diabetic patients without evidence of renal disease should remain in the realm of clinical research.  相似文献   
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Treatment of juvenile patients with a missing maxillary incisor is difficult, because an implant cannot be placed until growth is completed. The other minimally invasive alternatives are also problematic: Removable dentures are rarely accepted by juvenile patients, and the conventional resin-bonded fixed partial denture often provides a poor esthetic result because the metal retainer causes the abutment teeth to lose their natural translucency and to become grayish. Moreover, the alveolar ridge defect makes it easy to identify the prosthesis in the pontic area. The present case report describes the prosthetic treatment of a juvenile patient who had lost a maxillary incisor to trauma. To avoid the disadvantages of conventional therapies, subepithelial connective tissue was grafted to reshape the alveolar ridge. The space was closed with an all-ceramic resin-bonded fixed partial denture.  相似文献   
15.
A transformation algorithm is introduced to specify eye rotations in three dimensions from two-dimensional translations of ocular fundus landmarks dynamically monitored by means of the novel Scanning Laser Ophthalmoscope (SLO). The rotation parameters are expressed as Y-X-Z Euler angles and in terms of the rotation axis and one rotation angle. Additionally, the angular distance of the retinal stimulus projection can be evaluated relative to the fovea. By simultaneously operating as eye movement measurement device, fundus camera, and visual target projector, the SLO opens a variety of new applications for the combined analysis of eye movements and the underlying 'retinal events' in vision and oculomotor research.  相似文献   
16.
Forty-nine patients were treated with either 3×75 MBq 89Sr or saline as placebo. Analysis of results 1 to 3 years after therapy revealed the ineffectiveness of 89Sr to relieve pain from metastases. Unexpectedly, a higher survival rate was found after Sr application (46% vs 4% after 2 years). Covariate analysis underlines the effect of 89Sr therapy on life expectation.  相似文献   
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The natural history of focal segmental glomerulosclerosis in patients retransplanted after loss of a primary allograft is not well established. We studied 14 patients with FSGS who were retransplanted between April 1964 and September 1990 to determine if recurrence in a second or subsequent allograft could be predicted. In this group, 8 of the primary allografts were lost to recurrent disease and 6 to rejection. None of the 6 patients who lost their primary allograft to rejection without evidence of recurrent FSGS suffered recurrent disease after retransplantation. In contrast, 3 of the 8 patients who lost their primary allograft rapidly to FSGS suffered recurrent disease and loss of function in all subsequent allografts. The remaining 5 patients had prolonged function of the primary allograft ranging between 4 and 10.5 years, despite recurrence of FSGS. Of these 5 patients, 2 have excellent renal function after retransplantation without recurrence of FSGS in the secondary allograft at 9 and 10.5 years posttransplant; 2 have lost their secondary allograft to recurrent FSGS, but are free of recurrence in the third allograft at 0.5 and 5.8 years postoperatively; 1 maintains a serum creatinine level of 1.9 mg% despite recurrence of FSGS in the secondary allograft at 1 year postoperatively. Our data show that, without recurrence of FSGS in the primary allograft, further renal transplants will be free of recurrent disease. Based on this finding, we advocate use of living-related donors for second transplants in these patients. With rapid recurrence of FSGS and subsequent accelerated loss of the primary allograft, further renal transplants carry a high likelihood of recurrent FSGS and graft loss. A substantial proportion of patients with recurrent FSGS in the primary allograft will have prolonged renal function, and are likely to have excellent results with subsequent allografts.  相似文献   
18.
Depression is a serious and potentially life-threatening mental illness, which does not only lead to personal suffering but also impairs social functioning and has a significant socioeconomic effect. Epidemiological studies have found a life-time prevalence of up to 17% in the general population and death due to suicides of up to 15%. As women have a two-fold higher prevalence for depressive disorder, it is noteworthy that suicide rates are consistently higher for men. Previous studies have suggested that mainly men suffer from a specific irritable depressive syndrome, which is characterized by lowered impulse control, symptomatic substance abuse, an increased readiness to take risks, and anger attacks, which present as sudden spells of inappropriate anger with vegetative hyperarousal. This article reviews gender-specific aspects of depressive disorder focussing on anger attacks and their clinical management.  相似文献   
19.
The aim of this study was to compare nonfluoroscopic electroanatomic mapping (NOGA), SPECT perfusion imaging, and PET metabolic imaging for assessment of myocardial viability. In particular, we sought to elucidate differences of electromechanical properties between the perfusion/metabolism mismatch as an indicator of a potentially reversible ischemic injury and the perfusion/metabolism match indicating irreversibly damaged myocardial tissue. METHODS: Twenty-one patients with coronary artery disease underwent NOGA mapping of endocardial unipolar voltage, cardiac 18F-FDG PET of glucose utilization, and resting 201Tl SPECT of myocardial perfusion. RESULTS: Electrical activity was 10.8 +/- 4.6 mV (mean +/- SD) in normal myocardium and was unchanged in hypoperfused segments with maintained glucose metabolism (perfusion/metabolism mismatch), 9.3 +/- 3.4 mV (P = not significant). In contrast, hypoperfused segments with a perfusion/metabolism match and nonviable segments showed significantly lower voltage (6.9 +/- 3.1 mV, P < 0.0001 and 4.1 +/- 1.1 mV, P < 0.0001 vs. normal). In hypoperfused segments, metabolic activity was more closely related to endocardial voltage than was myocardial perfusion (201Tl vs. voltage: r = 0.38, SEE = 3.2, P < 0.001; 18F-FDG PET vs. voltage: r = 0.6, SEE = 2.8, P < 0.0001). CONCLUSION: In hypoperfused myocardium, electrical activity by NOGA mapping is more closely related to PET metabolic activity than to SPECT myocardial perfusion. As NOGA mapping does not differentiate hypoperfused myocardium with enhanced glucose utilization from normal myocardium, results from NOGA mapping need to be correlated with results from perfusion imaging to identify hypoperfused, yet viable, myocardium and to stratify patients for revascularization procedures.  相似文献   
20.
Dietmar B?nsch  Matthias Antz 《Herz》2005,11(1):119-122
Elektrophysiologische Untersuchungen (EPU) und programmierte Ventrikelstimulationen (PVS) werden vor der Implantation eines Defibrillators (ICD) empfohlen, wenn Patienten ohne nachweisbare strukturelle Herzerkrankung oder mit hypertrophischer obstruktiver Kardiomyopathie (HOCM) einen Herzstillstand überlebt haben, weil die Prävalenz von prinzipiell kurierbaren Rhythmusstörungen wie idiopathischen ventrikulären Tachykardien (VT), bei diesen Patienten hoch ist. Gleiches gilt für Patienten nach überlebtem Herzstillstand mit einer kurzen PQ-Zeit oder einer Deltawelle. Patienten mit Tachykardien, bei denen die Diagnose VT unsicher ist, sollten ebenfalls einer EPU unterzogen werden. Wenn sich Patienten mit nicht anhaltenden Tachykardien oder Synkopen vorstellen, sind eine EPU und PVS zur Risikostratifizierung indiziert. Bei den übrigen Patienten mit eingeschränkter linksventrikulärer Pumpfunktion nach überlebtem Herzstillstand oder instabiler VT, die Kandidaten für eine ICD-Implantation sind, haben die EPU und PVS möglicherweise nur einen geringen Nutzen.  相似文献   
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