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971.
A comparative study of three subgroups of meniscal transplants was undertaken in the goat model: Group 1 (autograft) involved removal and immediate reimplantation of the meniscus; Group 2, fresh meniscal allografts; and Group 3, cryopreserved (30 days) meniscal allografts. Six months after surgery, tissues were evaluated for gross degenerative changes, proteoglycan concentration (as assessed by uronic acid), water content, vascularity, histology, and cell viability. The contralateral knee served as control for all comparisons. There was no statistical difference in the amount of arthritis present and all transplants demonstrated an essentially normal peripheral vascularity compared to controls. Sections revealed reduced numbers of cells in the central portions of the transplanted menisci and these viable cells demonstrated different behavior in multiplication in tissue culture compared to contralateral controls. Grossly and microscopically, the implanted menisci differed little from the controls. The measurement of proteoglycan concentration and water content of the transplanted meniscal cartilage suggest alterations that may affect the long-term mechanical properties. The autograft specimens showed the water content was very slightly increased (3% to 6%), while the proteoglycan concentration was increased (42% in terms of uronic acid). In contrast, the water content of the fresh allograft group and the cryopreserved group was increased 12% to 24%. Proteoglycan concentration in these groups was decreased up to 56% in portions of some menisci compared to controls. Fresh and cryopreserved meniscal allografts showed peripheral healing, revascularization, cellularity, and incorporation, and grossly appeared good at 6 months in the goat model. The biochemical changes in the extracellular matrix at 6 months raises questions on the long-term function of these transplanted menisci.  相似文献   
972.
Chronic thalamic-VIM stimulation was performed in 9 parkinsonian patients with disabling tremor and poor response to drugs. Neuropsychological assessment was performed before and after deep brain electrode implantation and stimulation. Mild cognitive disorders were observed prior to thalamic implantation. Neuropsychological testing failed to show intellectual function worsening after implantation and stimulation. We conclude that thalamic stimulation could be an appropriate treatment of untractable tremor as this could provide less neuropsychological side-effects than thalamotomy, especially in Parkinson's disease.  相似文献   
973.
A study of the angiographic findings in consecutive civilian patients with cranial gunshot wounds examined in the acute stage has not been done. Most prior clinical studies have evaluated the findings in survivors in the subacute or chronic stages and have often been of war-time casualties. We determined the clinicoradiologic features of six cases of posttraumatic intracranial aneurysm, vascular occlusion, or arteriovenous fistula caused by penetrating missiles among 12 civilian patients who were examined in the acute posttraumatic stage (within 48 hr of injury) during a 1-year period. Three internal carotid/vertebral artery aneurysms, one external carotid artery aneurysm, one combined aneurysm/arteriovenous fistula of the vertebrobasilar circulation, and one cerebral venous occlusion were identified. The 50% overall prevalence of major vascular lesions in this series of civilian patients with penetrating missile injuries examined in the acute stage suggests these injuries are more common than previously suspected. It may indicate that selective cerebral angiography should be considered in the evaluation of the cranial vascular system of such persons.  相似文献   
974.
Extraadrenal pheochromocytoma: dynamic demonstration at 0.5 tesla.   总被引:1,自引:0,他引:1  
We report a case of extraadrenal pheochromocytoma of Zuckerkandl imaged by dynamic magnetic resonance imaging (dynamic MRI) with a 0.5 tesla (T) machine. The dynamic MRI proved useful in disclosing the tumor clearly because of strong enhancement in its early phase. This case has the advantages of dynamic computed tomography (dynamic CT) as well as of T2-weighted spin-echo (SE) MR images.  相似文献   
975.
The value of MR imaging was compared with that of high-resolution CT in assessing chronic infiltrative lung disease in 25 patients. The cases included nine patients with usual interstitial pneumonia, six with sarcoidosis, four with hypersensitivity pneumonitis, and six with miscellaneous conditions. The diagnosis was proved by biopsy (n = 17) or by means of clinical, laboratory, and radiologic criteria (n = 8). All patients had 1.5-T MR imaging and CT of the chest. Cardiac-gated T1-, proton density-, and T2-weighted spin-echo sequences were obtained. Initially, the MR images were assessed independently; later they were compared directly with the corresponding CT scans. In six patients, MR images and CT scans were obtained before open lung biopsy, and the images and scans were assessed prospectively. CT was superior to MR imaging in the anatomic assessment of the lung parenchyma and in showing fibrosis. However, areas of air-space opacification (ground-glass opacities) were seen as well on MR as on high-resolution CT. In the six patients who had open lung biopsy, areas of air-space opacification seen on MR and on CT corresponded to areas of active alveolitis or air-space infiltrates pathologically. Follow-up in six patients showed equal degrees of change in the air-space opacification over time on MR and CT. We conclude that, although MR imaging is inferior to high-resolution CT in the assessment of chronic infiltrative lung diseases, it may play a role in the assessment and follow-up of patients with air-space opacification.  相似文献   
976.
The pulmonary lesions were studied in 24 autopsy cases of Japanese patients with AIDS. The major pathological findings were opportunistic infections, which were the major clinical symptoms in some patients. The pathogens identified were as follows; Pneumocystis carinii (PC) in 10, cytomegalovirus (CMV) in 14, atypical mycobacterium in 5, cryptococcus in 2, candida in 2, and nocardia in 1. PC pneumonia was prominent in 8 cases and was the cause of death. In such patients, the lung were heavy and appeared parenchymatous. Histological examination revealed numerous protozoa in the foamy material in the alveolar spaces, associated with swelling of the alveolar lining cells and edematous thickening of the alveolar septa. In some cases, only hyaline membrane formation was prominent without foamy material in the alveolar spaces. Immunostaining with anti-PC monoclonal antibody or in-situ hybridization with oligopeptide demonstrated pathogens in the hyaline membranes. Many cases with PC pneumonia had concomitant opportunistic infections such as CMV, Herpes simplex virus, and atypical mycobacterium. Extrapulmonary infection of PC was seen in only one case. CMV infection was found in 14 cases; 7 had innumerable inclusion bodies, and in some cases the lesions were most prominent around the bronchioles. Of the 5 cases of atypical mycobacterial infection, 2 were caused by M. kansaii (MK) and 3 by M. avium intracellulare (MAI). Both lesions of MK infection showed necrosis and cavitation. One of three cases of MAI infection showed cavitation. Around the cavitary lesions, numerous cytomegalic inclusion bodies were identified in the mesenchymal cells, which may have been the cause of necrosis and cavitation of the lesions. MAI infection was systemic and pronounced in the lymph nodes, spleen, and intestinal mucosa. Neoplastic lesions comprised 2 cases of Kaposi's sarcoma and 4 of extranodal non-Hodgkin lymphoma in other organs. Lung involvement was seen in only one case of Kaposi's sarcoma although very small in size. The lesion was situated along the pulmonary vein and appeared hemorrhagic macroscopically. Pulmonary lesions in AIDS are complicated, and many of opportunistic pathogens were identified in single patients.  相似文献   
977.
We encountered a rare case of hypersensitivity pneumonitis associated with bilateral hilar lymphadenopathy (BHL). The patient was a 53-year-old male, who developed dry cough and shortness of breath when using a humidifier since 1982. He was admitted to our hospital for further evaluation in 1987. Chest X-ray films showed BHL and ground glass appearance in the bilateral lung fields. Pulmonary function test indicated disturbance of diffusing capacity. Transbronchial lung biopsy revealed interstitial pneumonitis, and lymph node biopsy by mediastinoscopy showed lymphoid sinus histiocytosis without noncaseating granuloma. Provocation test using the humidifier was positive, and the diagnosis of humidifier lung with BHL was made.  相似文献   
978.
OBJECTIVE--To determine the changes in the endocrine mechanisms of fluid balance after cardiopulmonary bypass in children. DESIGN--Prospective study; analysis of numbered plasma samples performed blind with respect to clinical data. SETTING--Regional paediatric cardiothoracic unit. PATIENTS--Nine patients, median age 4, range 2 to 9 years, five males. Patients under the age of 1 year were excluded because of the frequent blood sampling involved. MAIN OUTCOME MEASURES--Plasma concentrations of atrial natriuretic peptide (ANP), arginine vasopressin, plasma renin activity, aldosterone, noradrenaline and adrenaline, and urinary concentrations of cyclic guanosine monophosphate (cGMP) as measured by radioimmunoassay. RESULTS--After 30 minutes of cardiopulmonary bypass plasma atrial natriuretic peptide (ANP) decreased from (mean (SEM)) 151 (71) pg/ml to 52 (44) pg/ml (NS), and urinary production of its second messenger cyclic guanosine monophosphate (cGMP) decreased from 1286 (600) pmol/ml to 151 (414) pmol (p < 0.05). Other plasma concentrations of hormones studied did not change significantly although arginine vasopressin, adrenaline, and noradrenaline increased whereas aldosterone and plasma renin activity decreased. After cardiopulmonary bypass stopped there was an immediate and significant rise in plasma ANP, but within the next 24 hours plasma ANP declined significantly (p < 0.05), decreasing from 294 (49) pg/ml to 64 (29) pg/ml at 22 hours. In the postoperative period there was a significant correlation between plasma ANP and both mean fluid balance (r = 0.96, p < 0.001) and mean urine output (r = 0.97, p < 0.001). Plasma aldosterone peaked (p < 0.05) at 22 hours after operation, and argine vasopressin peaked (p < 0.05) at two hours and then declined (p < 0.05) to a trough at 24 hours. Plasma renin activity, adrenaline, noradrenaline, and urinary cGMP concentrations, and mean central venous pressure did not change significantly in the postoperative period. CONCLUSION--The changes documented show the differing pattern of release of water balance hormones invoked by cardiopulmonary bypass. The central role of ANP is shown by its strong correlation with urinary output and its similarly strong relation to fluid balance.  相似文献   
979.
To evaluate the early diastolic peak filling rate of the left ventricle, three groups of children (normal children, patients with aortic valvular stenosis, and patients with aortic coarctation) were examined with the peak filling rate normalized to stroke volume calculated from the mitral valve inflow Doppler recording as the peak E velocity divided by the velocity time integral. The normal value for this index in children was 6.78 +/- 0.99 SV/sec and did not vary with age, weight, body surface area, or heart rate. Compared with normal subjects, both patients with aortic stenosis and patients with coarctation had increased left ventricular mass, but patients with aortic stenosis had decreased normalized peak filling rates (5.3 +/- 0.84 SV/sec, p < 0.01), while patients with coarctation had normal rates (6.79 +/- 0.98 SV/sec, p = 0.97). Compared with patients with aortic coarctation, patients with aortic stenosis had higher Doppler gradients. Thus the Doppler index of peak filling rate normalized to stroke volume is particularly useful in children because it is independent of heart rate, age, weight, and body surface area. Patients with coarctation may have normal peak filling rates normalized to stroke volume despite increased left ventricular mass because of milder obstruction or better coronary artery perfusion compared with that of patients with aortic stenosis.  相似文献   
980.
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