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101.
Shoji TERAMOTO Ken L. TAKAHASHI Masayuki KIKUTA Hiroko KOBAYASHI 《Congenital anomalies》1999,39(1):31-35
3-Chloro-4-(dichloromethyl)-5-hydroxy-2( 5H )-furanone (MX) causes complete inhibition of rat embryonic midbrain (CNS) cell differentiation in the micromass in vitro test when applied at a concentration of 5 μ g/ml under conditions where MX is rapidly degraded in culture medium with a half-life of 56 min. This study investigated whether or not degradation products of MX have inhibitory effects on CNS cell differentiation following pre-incubation of MX in culture medium for 0.5, 1 or 2 hr. When MX was pre-incubated for 0.5 hr, the mean number of differentiated foci was 0.2 against 62.5 for the control. However, the number increased to 44.7 when pre-incubation time was extended to 2 hr. These results suggest that MX, but not its degradation products, is a teratogen in vitro. MX manifested almost complete inhibitory effects on CNS cell differentiation by 0.5 hr of exposure. 相似文献
102.
目的探讨羟基积雪草苷对铜锌超氧化物歧化酶(Cu,Zn superox ide d ism u tase,SOD 1)-G 93A突变肌萎缩侧索硬化(am yotroph ic latera l scleros is,ALS)小鼠的治疗作用。方法通过行为学和组织学测定,观察羟基积雪草苷对SOD 1-G 93A突变ALS小鼠发病时间、生存时间、运动功能变化和神经元病理改变的影响。结果羟基积雪草苷(61.1±11.0)和(185.6±18.7)m g/(kg.d)在小鼠日龄70 d时开始给药至死亡,能分别延长SOD 1-G 93A突变ALS小鼠的生存时间11.4和9.4 d,但对发病时间无影响;同时(61.1±11.0)m g/(kg.d)组小鼠在肌力缓慢下降期运动功能降低减缓,与对照组比较差异显著(P<0.05)。120 d时L 2~5组织切片显示两治疗组脊髓前角运动神经元数明显高于SOD 1-G 93A对照组(P<0.05),多数运动神经元胞浆中仍有尼氏体存在。结论羟基积雪草苷对SOD 1-G 93A突变转基因小鼠运动神经元变性有保护作用,能延长小鼠的生存时间。 相似文献
103.
Susumu YAMAKADO Atsushi TATSUGUCHI Jun SATO Shunji FUJIMORI Sadamu MEVAMI Fumihiko TAGUCHI Yasuhito TAMAGAWA Teruyuki KISHIDA Yutaka YOSHIDA Masafumi KOBAYASHI 《Digestive endoscopy》1995,7(3):234-239
Altered colonic mucosal blood flow (CMBF) is thought to be involved in the onset mechanism of ischemic colitis (IC). This study was designed to clarify the features of CMBF in six patients with IC (average age, 61 yr) and 10 control subjects (44.6yr). In the IC patients, CMBF was measured at both the affected site (ulcer margin and surrounding mucosa) and at a normal appearing site, during the active, healing, or recovery phase, by the laser doppler method. In the control group, CMBF was measured in various segments of the colon. The CMBF around the ulcer site during the active phase was significantly lower than that at the homologous segment in normal controls, while CMBF at normal sites in IC patients did not differ markedly from that of normal controls. CMBF in reddened portions of the ulcer margin in IC patients was significantly higher than that of the surrounding mucosa. A significant increase in CMBF was also observed during PGEi administration as compared to that before administration. This evidence clearly indicates that decreased CMBF is involved in the pathogenic mechanism of IC. The CMBF at sites of active mucosal restoration was somewhat increased. Continuous intravenous administration of PGEi was found to increase CMBF in IC patients. 相似文献
104.
HIRONORI YOSHIDA TOHRU ISHIKAWA FUMIO SHIRAISHI TOSHINORI KOBAYASHI 《Psychiatry and clinical neurosciences》1998,52(2):139-140
Abstract The effects of physical exercises taken at different times in the day upon subjective sleep feeling were examined in five healthy university students (aged 20–22 years); morning exercise, evening exercise, and late evening exercise. The late evening exercise with the strength of 50–60% VO2 max of 1 h has the effect of getting better subjective sleep feeling in the morning and the effect of the decreased daytime sleepiness. 相似文献
105.
TOSHIO KOBAYASHI KIWAMU MISAKI HIROKI NAKAGAWA KYOKO OKUDA TADAAKI OTA IZUMI KANDA KIMINORI ISAKI YOSIFUMI KOSINO HIDEMICHI FUKUDA 《Psychiatry and clinical neurosciences》1998,52(2):154-155
Abstract The influence of alcohol (ethanol) on sleep was investigated in 10 men. Polysomnography (PS) was recorded on a baseline night (BL-N) and an ethanol (0.8 g/kg) night (Et-N). On visual score rapid eye movement (REM) sleep was reduced, REM latency was prolonged on Et-N as compared to BL-N. Using the fast Fourier transformation method, electroencephalographic power density of REM sleep in δ frequencies band and in the 10–12 Hz range of non-REM sleep were enhanced. REM sleep and non-RJEM sleep changes were prominent in the second-half and first-half of the night, respectively. 相似文献
106.
107.
Magnetic resonance imaging study of the brain in aged volunteers: T2 high intensity lesions and higher order cortical function 总被引:1,自引:0,他引:1
HIROO KASAHARA md HIDEO YAMADA md MUNEHIKO TANNO md MITSURU KOBAYASHI AKIHIDE KARASAWA md KAZUO ENDO SADANOBU USHIJIMA md 《Psychiatry and clinical neurosciences》1995,49(5-6):273-279
Abstract The aims of the present study were to clarify the findings of magnetic resonance imaging (MRI) in the aging brain, and to relate the MRI findings to higher order cortical function. A total of 118 healthy aged volunteers (41 men, 77 women) underwent cranial MRI electroencephalography (EEG), Benton visual retention test (BVRT) and interview. The subjects had no past history or clinical evidence of cerebrovascular disorder, head trauma or dementia and were living at home without any difficulty. The majority of the subjects have participated in this series of studies since 1982. Using a 1.5 T superconductive MR instrument, T1-weighted, proton density and T2-weighted images were obtained. The MRI data were rated visually by regarding 12 items according to fixed criteria. T2 high signal intensity (T2HSI) lesions were found in 69.5% of subjects, the prevalence of which increased with age. T2HSI lesions were most frequently found in the basal ganglia (61.9%), followed by the thalamus (39.0%), parietal lobe (37.0%), temporal lobe (12.7%) and pons (8.5%). Among these lesions, lacunar infarction showed low signal intensity in T1-weighted images and was found in 24.6% of subjects, the prevalence also increasing with age. These findings, including brain atrophy determined according to similar criteria, were correlated closely with the subjects' age. The results of BVRT showed a close relation with T2HSI, suggesting that T2HSI may influence cognitive function. When the subjects were classified according to the presence of T2HSI, lacunar infarction and EEG abnormalities, brain atrophy was significantly milder in a group of subjects with T2HSI(-), lacunar infarction(-) and normal EEG than in the other groups. This suggests that changes seemingly representing physiological aging may be promoted by another pathological which also exerts influences on higher order cerebral function. 相似文献
108.
Ryutaro KOMURO Katsuji KOBAYASHI Masao SHIMAZAKI Kaoru SUGIMORI Yoshifumi KOSHINO Katsuaki SATOU Yoshio ODA 《Psychogeriatrics》2006,6(2):74-78
We report a 57‐year‐old patient with Creutzfeldt‐Jakob disease that initially presented with right parietal lobe syndrome. He featured early dystonic and hemiparetic posture of the left upper limb, finger agnosia, geographic disorientation and acalculia and developed myoclonus from the left upper extremity and right‐sided periodic synchronized discharges. He died 2 years and 3 months later. Brain autopsy revealed a marked reduction in brain weight, extensive cortical spongiform changes and white matter degeneration. Immunolabeled prion proteins were deposited diffusely in the neuropil. Accentuation of the cortical change was unclear but white matter degeneration was more severe in the right parietal lobe than in the left parietal lobe. Right parietal lobe syndrome is rarely reported as an initial symptom of Creutzfeldt‐Jakob disease and can be a clinical variant of the disease. 相似文献
109.