全文获取类型
收费全文 | 7596篇 |
免费 | 405篇 |
国内免费 | 35篇 |
专业分类
耳鼻咽喉 | 81篇 |
儿科学 | 97篇 |
妇产科学 | 53篇 |
基础医学 | 1148篇 |
口腔科学 | 249篇 |
临床医学 | 503篇 |
内科学 | 2160篇 |
皮肤病学 | 109篇 |
神经病学 | 545篇 |
特种医学 | 403篇 |
外科学 | 1109篇 |
综合类 | 30篇 |
预防医学 | 274篇 |
眼科学 | 72篇 |
药学 | 491篇 |
中国医学 | 7篇 |
肿瘤学 | 705篇 |
出版年
2022年 | 61篇 |
2021年 | 137篇 |
2020年 | 67篇 |
2019年 | 87篇 |
2018年 | 126篇 |
2017年 | 110篇 |
2016年 | 130篇 |
2015年 | 119篇 |
2014年 | 176篇 |
2013年 | 205篇 |
2012年 | 317篇 |
2011年 | 329篇 |
2010年 | 194篇 |
2009年 | 182篇 |
2008年 | 287篇 |
2007年 | 309篇 |
2006年 | 315篇 |
2005年 | 281篇 |
2004年 | 282篇 |
2003年 | 292篇 |
2002年 | 313篇 |
2001年 | 230篇 |
2000年 | 233篇 |
1999年 | 220篇 |
1998年 | 96篇 |
1997年 | 58篇 |
1996年 | 78篇 |
1995年 | 67篇 |
1994年 | 52篇 |
1993年 | 49篇 |
1992年 | 217篇 |
1991年 | 219篇 |
1990年 | 188篇 |
1989年 | 225篇 |
1988年 | 192篇 |
1987年 | 173篇 |
1986年 | 166篇 |
1985年 | 173篇 |
1984年 | 124篇 |
1983年 | 103篇 |
1982年 | 48篇 |
1981年 | 51篇 |
1979年 | 112篇 |
1978年 | 53篇 |
1977年 | 48篇 |
1975年 | 50篇 |
1974年 | 46篇 |
1973年 | 49篇 |
1972年 | 47篇 |
1968年 | 39篇 |
排序方式: 共有8036条查询结果,搜索用时 31 毫秒
991.
Noriaki Ikeda Yujiro Handa So Po Khim Callum Durward Tony Axéll Teruhisa Mizuno Hideo Fukano Tsuyoshi Kawai 《Community dentistry and oral epidemiology》1995,23(1):49-54
Abstract The aim of this study was to investigate the epidemiology of oral mucosal lesions in a selected Cambodian population to obtain pilot data useful in planning an oral health data base for the country. Due to unstable conditions in Cambodia, the validity of population data related to present census information is highly questionable. Therefore, prior to this investigation a census registration was carried out using local health workers as registrars in nine villages of a commune. In the period July 4–31, 1991, a total of 1319 individuals (953 women, 366 men, 15–99 yr) were examined by one oral surgeon in the nine villages of Kok Trop Commune. Kandal Stung District, southwest of the capital Phnom Penh. Clinical diagnoses were based on WHO criteria. Information on smoking habits, betel nut chewing habits, and alcohol use was collected by 4 Khmer dental personnel. In total, 71 lesions were recorded in 64 (4.9%) individuals. Leukoplakia was found in 1.1%, lichen lesions in 1.8%, candidosis in 1.4%, submucous fibrosis in 0.2%, cancer in 0.1%) and other diagnoses in 0.8%. The prevalence of leukoplakia was 2.2% and 0.6% among men and women respectively, a statistically significant difference (P < 0.05). There were significantly more smokers (P < 0.01) among subjects with leukoplakia (64.3%) than among those without this lesion (28.6%). All subjects with lichen lesions were women. The age-adjusted relative risk for developing lichen among betel nut chewers as compared to non-chewers was 3.3. This study has provided information on epidemiological aspects of oral mucosal lesions, including the relationship to etiological factors such as tobacco smoking and betel nut chewing, which might prove valuable in planning future oral health studies and implementing preventive programmes in Cambodia. 相似文献
992.
Takehisa Ishikawa Haruo Shimazaki Mitsuya Morita Mikio Sawada Yoshihisa Takiyama Imaharu Nakano Toshirou Kawai 《Clinical neurology》2005,45(1):32-37
A 54-year-old man with a history of partially dissected epidermoid cyst in the left cerebellopontine angle suffered from a slowly progressive dysesthesia and weakness in the lower extremities and trunk. Neurological examination revealed segmental muscular weakness and sensory disturbance in those regions, giving rise to the possibility of monoradiculopathy multiplex, as well as loss of tendon reflexes, dysuria and right facial nerve palsy. Electrophysiological studies indicated irregular motor axonopathy or neuronopathy and interruption of more central sensory pathways than the lumbosacral spinal nerve roots with spared peripheral sensory nerves. Although MRI demonstrated enhanced lesions in the cauda equina and lumbosacral leptomeninges, CSF cytology or a cauda equina biopsy showed no malignancy. His symptoms gradually progressed and he died 15 months after the onset. The autopsy failed to reveal any tumors in the general systemic internal organs. Histopathology demonstrated meningeal carcinomatosis with squamous-type carcinoma cells scattered in the cerebrospinal leptomeninges, and perineurium in almost all the spinal and cranial nerve roots, causing severe axonal degeneration. The dorsal root ganglions escaped tumor cell invasion. Absence of the malignant tumors in the systemic organs and the history of the operated epidermoid cyst indicate that the tumor may be the cause of the meningeal carcinomatosis in this case. Meningeal carcinomatosis almost always shows rapid progression and extremely poor prognosis with several month survival in general, and little attention has been paid that it can exhibit symptoms and signs of segmental involvement in the lumbosacral regions. Our present case prompts us to bear in mind that patients with this condition can survive fairly long, and raises the possibility that a careful neurological examination with segmental involvement will reveal such a feature more frequently than considered so far in this condition. 相似文献
993.
994.
K Masada Y Tsuyuguchi H Kawabata H Kawai K Tada K Ono 《Journal of pediatric orthopedics》1986,6(3):340-345
A total of 523 Japanese patients with terminal limb congenital malformations were reviewed for the characteristic features, and especially for type correlation between hand and foot anomalies. There were 281 cases of hand involvement alone, 149 cases of foot involvement alone, and 93 cases of combined hand and foot involvement. Polydactyly was commonly preaxial in the hand and postaxial in the foot, in contrast to the well-known postaxial dominance in the hand among whites. Hand anomalies were likely to show the same Swanson type of anomaly as the foot, with the affected digital ray likely to be identical in both hand and foot. 相似文献
995.
We investigated changes in bone marrow blood flow and histology with aging in rabbits. Bone marrow blood flow was measured by the hydrogen washout method, which was performed in the proximal tibia of Japanese white rabbits, 3-42 months of age. Bone marrow blood flow was found to decrease with age. Histological observations of the proximal tibia identified a decrease in the number of osteoblasts and hematopoietic cells, an increase of the number of empty lacunae, a reduction in bone formation rate, and a degeneration of marrow fat with aging. These results suggest that the decrease of bone marrow blood flow is related to histological changes found with aging. 相似文献
996.
Epileptic seizures in the 4p- syndrome: report of two cases. 总被引:3,自引:0,他引:3
We report ictal phenomena in two patients with the 4p- syndrome captured on simultaneous video-EEG monitor. One patient, diagnosed as having partial epilepsy, had complex partial seizures and hemiconvulsive status epilepticus. This was associated with more severe mental retardation. The second patient was diagnosed as having the West syndrome and exhibited tonic spasms with a cluster formation. We conclude that various types of epileptic seizures may occur in patients with the 4p- syndrome, including grand mal and myoclonic seizures. 相似文献
997.
998.
We studied the relation between cerebral white matter damage and clinical data in nine patients with dentatorubropallidoluysian atrophy (DRPLA). All patients showed pseudo-Huntington form. The study produced five results. (1) The four of the nine patients showed diffuse hypodensity of the cerebral white matter on CT. We studied one of this four patients by MRI. The hypodensity area on CT showed marked high signal intensity by T2-weighted image on MRI. (2) The onset age was later in the patients with cerebral white matter damage as compared with the patients without this damage. (3) All patients showed subcortical dementia, which was more remarkable in the patient with white matter damage. This suggests the relation between cerebral white matter damage and progression rate of subcortical dementia in DRPLA. (4) Gait disturbance progressed more rapidly in the patients with cerebral white matter damage. (5) The homovanillic acid (HVA) and 5-hydroxyindole acetic acid (5-HIAA) concentration in CSF decreased more remarkably in the patients with white matter damage. 相似文献
999.
1000.
K Hiki Y Yui R Hattori H Eizawa K Kosuga C Kawai 《Japanese journal of pharmacology》1991,56(2):217-220
Cytotoxic activated macrophages were sonicated and centrifuged. The activity of nitric oxide (NO) synthase was present in the supernatant and independent of Ca2+. The pellets were washed three times and treated with buffer containing 0.1% Triton X-100 or buffer alone, followed by centrifugation. The supernatant containing Triton X-100 showed NO synthase activity that was dependent on Ca2+, whereas the supernatant without the detergent had little activity. These data suggest that there are two forms of NO synthase: cytosolic and membrane-bound enzymes. 相似文献