全文获取类型
收费全文 | 270773篇 |
免费 | 19893篇 |
国内免费 | 1156篇 |
专业分类
耳鼻咽喉 | 3003篇 |
儿科学 | 7328篇 |
妇产科学 | 5132篇 |
基础医学 | 35619篇 |
口腔科学 | 5171篇 |
临床医学 | 27509篇 |
内科学 | 56953篇 |
皮肤病学 | 3666篇 |
神经病学 | 25935篇 |
特种医学 | 9192篇 |
外国民族医学 | 11篇 |
外科学 | 41212篇 |
综合类 | 3799篇 |
一般理论 | 360篇 |
预防医学 | 23203篇 |
眼科学 | 6858篇 |
药学 | 18211篇 |
5篇 | |
中国医学 | 377篇 |
肿瘤学 | 18278篇 |
出版年
2023年 | 1270篇 |
2022年 | 1605篇 |
2021年 | 5716篇 |
2020年 | 3463篇 |
2019年 | 5621篇 |
2018年 | 6301篇 |
2017年 | 4754篇 |
2016年 | 5251篇 |
2015年 | 6187篇 |
2014年 | 9113篇 |
2013年 | 12473篇 |
2012年 | 19007篇 |
2011年 | 19954篇 |
2010年 | 11160篇 |
2009年 | 9901篇 |
2008年 | 17530篇 |
2007年 | 18483篇 |
2006年 | 18243篇 |
2005年 | 18221篇 |
2004年 | 17016篇 |
2003年 | 15864篇 |
2002年 | 14734篇 |
2001年 | 2723篇 |
2000年 | 2212篇 |
1999年 | 2823篇 |
1998年 | 3273篇 |
1997年 | 2753篇 |
1996年 | 2377篇 |
1995年 | 2294篇 |
1994年 | 1927篇 |
1993年 | 1721篇 |
1992年 | 1720篇 |
1991年 | 1594篇 |
1990年 | 1428篇 |
1989年 | 1393篇 |
1988年 | 1352篇 |
1987年 | 1296篇 |
1986年 | 1250篇 |
1985年 | 1335篇 |
1984年 | 1499篇 |
1983年 | 1377篇 |
1982年 | 1516篇 |
1981年 | 1435篇 |
1980年 | 1245篇 |
1979年 | 912篇 |
1978年 | 925篇 |
1977年 | 768篇 |
1976年 | 711篇 |
1975年 | 613篇 |
1974年 | 623篇 |
排序方式: 共有10000条查询结果,搜索用时 187 毫秒
991.
This study compares the histology of the plantar-digital nerve supplying the third web space in asymptomatic patients with those who have clinically diagnosed Morton's metatarsalgia. Despite several studies concentrating on the histological changes in the interdigital nerve, the relevance of these changes is a matter of contention while the exact pathological process responsible for the symptoms has not been determined. The histological findings in control patients were identical to Morton's patients with the exception of demyelination, which was more common in the Morton's group. This suggests that the characteristic nodule and fibrotic changes seen in the interdigital nerves of patients with Morton's neuroma cannot account for the symptoms and that the changes seen in the neurovascular bundle are degenerative in origin and are found in asymptomatic patients. 相似文献
992.
MR imaging of neurocysticercosis 总被引:1,自引:0,他引:1
C S Zee H D Segall W Boswell J Ahmadi M Nelson P Colletti 《Journal of computer assisted tomography》1988,12(6):927-934
Magnetic resonance (MR) was performed in 50 patients with neurocysticercosis. Comparison was made with other neuroradiological imaging modalities including CT, myelography, CT ventriculography, and CT myelocisternography. Eighteen patients were found to have intraventricular cysts. In several patients, these were multiple and 22 intraventricular cysts were discovered. Although 4 of the 22 ventricular cysts were missed by MR, T1-weighted images can play a significant role in the early detection of intraventricular cysticercosis cysts, showing the cyst wall (9 of 22), a high intensity mural nodule (6 of 22), and increased signal intensity of the cyst fluid (5 of 22). Cisternal cysts (14 cysts in 10 patients) could be identified; they appear similar to intraventricular cysts, but mural nodules are infrequently seen (1 of 14). Twenty-nine patients had 69 parenchymal cysts. An attempt was made to assess the viability of these parenchymal lesions by matching the CT and MR findings with the Escobar pathologic staging system. Neuroimaging findings seemed compatible with early parenchymal lesions in the vesicular stage in 11 instances. Findings in cases with later stage cysts tend to support the concept that a dying larva provokes pronounced inflammatory reaction in the adjacent brain. Computed tomography remains the superior modality for depicting parenchymal calcifications within dead larvae. A case of a spinal cysticercosis cyst demonstrated with MR (in a patient with extensive intracranial cisternal cysts and a fourth ventricular cyst) is described. 相似文献
993.
The authors previously described a method of windowing the femur that allowed good exposure for femoral cement removal and provided for reconstruction of the defect. Since that report, they have developed instrumentation to facilitate windowing of the femoral shaft. They describe its use in this report. 相似文献
994.
995.
The progressive syndrome of Kearns-Sayre has been studied at the clinical, biochemical and genetic levels in a patient. Clinical arguments suggest an evolution from Pearson's disease to Kearns-Sayre syndrome. The respiratory chain activities were low, and Southern blot analysis, together with gene sequencing, showed a heteroplasmic deletion of 7767 base pairs in a significant proportion of the mitochondrial DNA in different tissues. Protein synthesis studies on lymphoblasts did not reveal any translation of the new reading frame created by the deletion, although the corresponding deleted mitochondrial DNA sequence is transcribed. 相似文献
996.
Magnetic resonance imaging of the adrenal glands was performed in 9 patients with Addison’s disease to evaluate the role of magnetic resonance (MR) in this entity. All patients had bilateral adrenal masses demonstrated by computed tomography (CT); etiologies included adrenal hemorrhage (2 patients), granulomatous disease (1 patient), adrenal lymphoma (3 patients), and adrenal metastases (3 patients). Spin-echo axial images were obtained at repetition times (TR) 0.5, 2.0 s and TE 28, 56 ms, using a Diasonics superconducting magnet operating at 0.35 T. In the patients with lymphoma, metastases, and granulomatous disease, the adrenal masses appeared hypointense or isointense with liver on the T1-weighted images (TR 0.5 s, TE 28 ms). In cases of adrenal hemorrhage, areas of hyperintensity were seen on TR 0.5, TE 56 ms sequences, due to shortening of T1 values. In both groups of patients the masses were hyperintense on T2 weighted sequences. Mean calculated T1 of the hemorrhagic glands was 449 ms, compared with a mean of 782 ms for mestastases and lymphoma. While MR is not capable of distinguishing between acute inflammatory and metastatic disases of the adrenal glands, it may be equally efficacious as CT in suggesting the diagnosis of adrenal hemorrhage in patients with Addison’s disease. 相似文献
997.
Meningiomas have been reported following radiation of the head, usually with a long latent interval between exposure and the diagnosis of the new tumor. We report a benign meningioma resected approximately 3 1/2 years after radiation therapy for a glioma, which represents an unusually short latent interval between radiation and new tumor growth. 相似文献
998.
999.
1000.
M Nelson 《Respiratory management》1988,18(4):29-32
By focusing on quality of life through education and ongoing support, the pulmonary rehabilitation staff at Little Company of Mary Hospital in Torrance, Calif, gives hope to respiratory patients and teaches them to become partners in the management of their disease. 相似文献