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41.
We present a case of a newborn with congenital rickets and radiographic evidence of secondary hyperparathyroidism in which the infant's mother had severe, longstanding untreated renal insufficiency. 相似文献
42.
Functional magnetic resonance studies of the reorganization of the human hand sensorimotor area after unilateral brain injury in the perinatal period. 总被引:6,自引:0,他引:6
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Y Cao E M Vikingstad P R Huttenlocher V L Towle D N Levin 《Proceedings of the National Academy of Sciences of the United States of America》1994,91(20):9612-9616
Functional magnetic resonance imaging was used to map the hand sensorimotor area of hemiparetic adolescents and young adults who had suffered unilateral brain damage in the perinatal period. Unlike normal subjects, who exhibit cortical activation primarily contralateral to voluntary finger movements, the hemiparetic patients' intact hemispheres were equally activated by contralateral and ipsilateral finger movements. Our findings are consistent with previous clinical observations and animal experiments which suggest that the immature brain is able to reorganize in response to focal injury. 相似文献
43.
G. A. Broderick P. A. Longhurst P. E. Juniewicz A. J. Wein R. M. Levin 《World journal of urology》1994,12(5):245-248
Summary Benign prostatic hyperplasia (BPH) is a major medical problem in the United States. The primary medical complication of BPH is progressive obstruction of the urethra and a subsequent in reduction the ability or the bladder to empty efficiently. The urodynamic characteristics associated with BPH include hyperreflexia, increased bladder capacity, increased frequency, decreased flow rate, and increased residual volume. Although there currently are individual animal models of prostate enlargement and animal models of partial outlet obstruction, there is no model of progressive obstruction secondary to prostate enlargement. The primary objective of the current study was to develop a canine model of BPH that would secondarily result in partial urethral obstruction and impaired urodynamics. Our model consists of encapsulating the prostate in a nylon mesh to prevent the growth of the prostate into the peritoneal cavity and then treating the dog with steroids to induce prostate growth and subsequently produce urethral constriction. The results demonstrate that encapsulation of the dog prostate and administration of steroids results in an increase in prostate mass simultaneously with an increase in urethral pressure and in changes in bladder contraction consistent with the presence of partial outlet obstruction. This preliminary study demonstrates that by preventing the outward growth of the steroid-stimulated prostate, urethral obstruction resembling BPH can be produced.This work was supported in part by grants from the Veterans Administration, NIH grants RO-1-DK 26508 and RO-1-DK33559, and the Stterling Winthrop Pharmaceuticals Research Division. 相似文献
44.
Current status of magnetic resonance imaging of the wrist. 总被引:2,自引:0,他引:2
P L Munk A D Vellet M F Levin L S Steinbach C A Helms 《Journal l'Association canadienne des radiologistes》1992,43(1):8-18
Conventional imaging of the wrist has relied heavily on plain radiography, tomography, fluoroscopy and arthrography. More recently, computed tomography and magnetic resonance imaging (MRI) have been added to this armamentarium. In this article the authors review the normal anatomy of the wrist and demonstrate a variety of pathologic conditions that can be assessed with MRI, including avascular necrosis and tears of the intrinsic and the extrinsic ligaments and the triangular fibrocartilage. MRI of the wrist is still evolving rapidly, and its place in the work-up of wrist disorders is only now being defined. 相似文献
45.
46.
Tumors of the hypothalamus present with a variety of clinical syndromes. Such syndromes appear to be both age and histology dependent. The diencephalic syndrome, an entity classically seen in infancy, presents as failure to thrive. In essentially all cases the pathologic substrate is a tumor with a predominance of gliomas. The traditional approach to treatment of the diencephalic syndrome has been surgery both for decompression and pathologic diagnosis followed by irradiation. Because of the tumor location, surgery is often confined to biopsy rather than radical extirpation. Furthermore, in infancy focal brain irradiation is not without significant morbidity. Within this context, we would like to present a case discussion regarding a 27-month-old boy with a hypothalamic-midbrain protoplasmic glioma treated with primary chemotherapy after surgical biopsy and pathologic documentation. The schedule of drugs utilized was based on the hypothesis of biochemical modulation of nitrosourea chemotherapy. Successful response to therapy was documented by sequential computed tomography (CT) studies and serial neurologic examinations beginning at age 5 months and every 2 months thereafter. The response of a single patient with the diencephalic syndrome treated primarily with chemotherapy makes extrapolation premature. Rather, the authors suggest chemotherapy as an alternative to focal brain irradiation. Such therapy could be utilized either in the event of recurrent tumor or as late consolidation after primary treatment with chemotherapy. The latter approach would allow a patient to have radiation therapy deferred until a later age at which time morbidity attending brain irradiation may be minimized. 相似文献
47.
Diagnosis and treatment of sacral and retrorectal tumors. I 总被引:1,自引:0,他引:1
48.
L S Levin R D Goldner J R Urbaniak J A Nunley W T Hardaker 《Journal of orthopaedic trauma》1990,4(4):432-440
Limb salvage was successful in 25 patients treated for severe grade III upper extremity injuries. In a retrospective review of 20 men and five women, follow-up time averaged 26 months. These high-energy injuries were characterized by massive soft-tissue injury, highly comminuted fractures, and significant neurovascular injury. Farm, industrial, and vehicular accidents accounted for 80% of the cases. Over 50% of the patients had concomitant systemic and/or other significant extremity injuries. Initial treatment consisted of irrigation and debridement and fracture stabilization using external and/or internal fixation. An average of four additional surgical procedures was required to provide soft-tissue coverage and maximum possible functional recovery. Forty-eight percent of the extremities underwent free vascularized or pedicular flaps for coverage or reconstruction. At final follow-up observation, 12% of the extremities rated excellent, 20% rated good, 52% fair, and 16% were poor. Experience gained in managing these severe upper extremity fractures supports the following observations. (a) Grade III open fractures of the upper extremities are frequently associated with significant neural, vascular, and musculotendon injuries. (b) External fixation plays an important role in the stabilization of grossly contaminated fractures. (c) Residual functional disability is common, and most patients do not return to their previous occupation. (d) Staged reconstruction directed toward maximum functional return may take several years. 相似文献
49.
Anulus fibrosus in bulging intervertebral disks 总被引:1,自引:0,他引:1
In this investigation the association of radial tears of the anulus fibrosus and bulging of the intervertebral disk was studied. An index of disk bulging was measured in sagittal anatomic sections in 149 lumbar disks from 31 cadavers. The indexes of disk bulging were correlated with stages of disk development and the presence of an annular tear. The largest disk-bulging indexes were always associated with radial tears of the anulus. Eighty-four percent of the disks with radial tears had disk-bulging indexes greater than 2.5 mm. Most normal adult disks had an index of less than 2.5 mm. The results challenge the concept that the anulus fibrosus is intact in bulging disks, although ruptured in herniated disks. 相似文献
50.
T Hoshino L A Rodriguez K G Cho K S Lee C B Wilson M S Edwards V A Levin R L Davis 《Journal of neurosurgery》1988,69(6):839-842
The proliferative potential of low-grade astrocytomas was estimated in 47 patients. Each patient received an intravenous infusion of bromodeoxyuridine (BUdR), 150 to 200 mg/sq m, at the time of craniotomy to label cells in deoxyribonucleic acid (DNA) synthesis; the percentage of S-phase cells, or BUdR labeling index (LI), of each tumor was determined immunohistochemically. In 29 patients (60%), the tumors had BUdR LI's of less than 1%, indicating a slow growth rate; only three (10%) of these patients died of recurrent tumor during a follow-up period of up to 3 1/2 years. In contrast, of the 18 patients (40%) whose tumors had BUdR LI's of 1% or more, 12 (67%) had a recurrence and nine died during the same follow-up period. These results show that the proliferative potential, as reflected by the BUdR LI, is an important prognostic factor that separates low-grade astrocytomas into two groups and provides a more scientific rationale for selecting treatment for individual patients. 相似文献