全文获取类型
收费全文 | 8984篇 |
免费 | 730篇 |
国内免费 | 61篇 |
专业分类
耳鼻咽喉 | 64篇 |
儿科学 | 320篇 |
妇产科学 | 304篇 |
基础医学 | 1173篇 |
口腔科学 | 282篇 |
临床医学 | 853篇 |
内科学 | 1866篇 |
皮肤病学 | 84篇 |
神经病学 | 537篇 |
特种医学 | 356篇 |
外科学 | 1485篇 |
综合类 | 192篇 |
一般理论 | 10篇 |
预防医学 | 431篇 |
眼科学 | 340篇 |
药学 | 480篇 |
中国医学 | 31篇 |
肿瘤学 | 967篇 |
出版年
2024年 | 9篇 |
2023年 | 58篇 |
2022年 | 75篇 |
2021年 | 214篇 |
2020年 | 144篇 |
2019年 | 191篇 |
2018年 | 255篇 |
2017年 | 136篇 |
2016年 | 193篇 |
2015年 | 242篇 |
2014年 | 337篇 |
2013年 | 356篇 |
2012年 | 547篇 |
2011年 | 628篇 |
2010年 | 392篇 |
2009年 | 367篇 |
2008年 | 555篇 |
2007年 | 599篇 |
2006年 | 567篇 |
2005年 | 516篇 |
2004年 | 460篇 |
2003年 | 411篇 |
2002年 | 316篇 |
2001年 | 304篇 |
2000年 | 257篇 |
1999年 | 210篇 |
1998年 | 87篇 |
1997年 | 90篇 |
1996年 | 69篇 |
1995年 | 52篇 |
1994年 | 54篇 |
1993年 | 49篇 |
1992年 | 113篇 |
1991年 | 98篇 |
1990年 | 101篇 |
1989年 | 101篇 |
1988年 | 73篇 |
1987年 | 75篇 |
1986年 | 67篇 |
1985年 | 74篇 |
1984年 | 49篇 |
1983年 | 41篇 |
1982年 | 33篇 |
1981年 | 37篇 |
1980年 | 28篇 |
1979年 | 24篇 |
1978年 | 20篇 |
1977年 | 26篇 |
1976年 | 17篇 |
1975年 | 15篇 |
排序方式: 共有9775条查询结果,搜索用时 15 毫秒
91.
Tamanini F; Willemsen R; van Unen L; Bontekoe C; Galjaard H; Oostra BA; Hoogeveen AT 《Human molecular genetics》1997,6(8):1315-1322
Lack of expression of the fragile X mental retardation protein (FMRP)
results in mental retardation and macroorchidism, seen as the major
pathological symptoms in fragile X patients. FMRP is a cytoplasmic RNA-
binding protein which cosediments with the 60S ribosomal subunit. Recently,
two proteins homologous to FMRP were discovered: FXR1 and FXR2. These novel
proteins interact with FMRP and with each other and they are also
associated with the 60S ribosomal subunit. Here, we studied the expression
pattern of the three proteins in brain and testis by immunohistochemistry.
In adult brain, FMR1, FXR1 and FXR2 proteins are coexpressed in the
cytoplasm of specific differentiated neurons only. However, we observed a
different expression pattern in fetal brain as well as in adult and fetal
testis, suggesting independent functions for the three proteins in those
tissues during embryonic development and adult life.
相似文献
92.
Jasmine green tea epicatechins are hypolipidemic in hamsters (Mesocricetus auratus) fed a high fat diet. 总被引:3,自引:0,他引:3
P T Chan W P Fong Y L Cheung Y Huang W K Ho Z Y Chen 《The Journal of nutrition》1999,129(6):1094-1101
These studies were designed to test the hypolipidemic activity of green tea epicatechins (GTE) isolated from jasmine green tea. In Experiment 1, three groups of hamsters were given a semisynthetic diet containing 200 g lard/kg and 1 g cholesterol/kg for 4 wk. The control group received distilled water, and the other two groups received either 15 g/L green tea water extract (GTWE) or 5.0 g/L GTE solution. Both the GTWE and GTE groups had lower concentrations of serum total cholesterol (TC) and triacylglycerols (TG) than the controls (P < 0.05). In Experiment 2, four groups of hamsters received tap water as the drinking fluid, but they were given the same high fat and cholesterol diet supplemented with 0 (control), 1.1, 3.4 or 5.7 g GTE/kg diet. The hypolipidemic effect of jasmine GTE was dose dependent. In Experiment 3, the time-course of changes in serum TC and TG was monitored in hamsters given the high fat diet supplemented with 5.7 g GTE/kg in comparison with that of controls. The hypolipidemic effects of dietary GTE were evident after feeding for 2 wk. Dietary supplementation of GTE did not affect liver fatty acid synthase. However, GTE-supplemented hamsters had higher fecal excretions of total fatty acids, neutral sterols and acidic sterols compared with the control group. In Experiment 4, hamsters were fed nonpurified diet; the control group drank distilled water, and the GTE group drank distilled water containing 5.0 g GTE/L. No differences in activities of 3-hydroxy-3-methyl glutaryl coenzyme A reductase and intestinal acyl CoA:cholesterol acyltransferase were observed. This study suggests that the hypolipidemic activity of GTE is not due to inhibition of synthesis of cholesterol or fatty acid but is most likely mediated by its influence on absorption of dietary fat and cholesterol. 相似文献
93.
The aim of the study was to evaluate the usefulness of the magnetic resonance (MR) perfusion maps in the detection of liver tumor perfusion following transcatheter arterial chemoembolization (TACE). MR dynamic susceptibility contrast-enhanced imaging was performed in 12 patients with 10 confirmed hepatocellular carcinoma and 2 confirmed hepatic metastasis using single-shot echoplanar pulse sequence. Time-intensity curves for all hepatic tumors showed a transient signal drop and the hepatic blood volume (HBV) maps were reconstructed. On the HBV maps, most tumors (80%) demonstrated hyperperfusion before TACE and hypoperfusion following TACE. The site and the degree of residual hyperperfusion within the tumor on the HBV maps correlated well with the areas of hypervascularity on the angiograms. In conclusion, the MR perfusion maps can be a promising technique for detecting the perfusion of the residual tumor tissue following TACE. 相似文献
94.
Hypertrophic olivary degeneration (HOD) is a rare type of neuronal degeneration involving the dento-rubo-olivary pathway. It is distinguished from other types of neuronal degeneration in that hypertrophy, rather than atrophy, takes place in the neurons in the inferior olivary nucleus. Prior to the invention of Magnetic Resonance Imaging (MRI), HOD was difficult to be detected, and a firm diagnosis could only be made at autopsy. We present a case of bilateral HOD following surgical excision of a cavernous hemangioma in the brainstem. The literature and imaging findings of this uncommon condition are reviewed. 相似文献
95.
96.
Dai Y Zhang S Yamamoto J Ao M Belin TR Cheung F Hifumi SS 《Community mental health journal》1999,35(6):537-542
There is a high prevalence of suicide amongelderly Chinese, and particularly among elderly Chinesewomen in Mainland China with a prevalence of 19.6 perhundred thousand. Since Chinese individuals may much more highly value education, acognitive-behavioral package originated by RicardoMunoz, Ph.D. was adapted for Chinese American subjects.The material was videotaped in eight sessions,approximately 25 minutes in length, to be shown to communitysubjects who were at least 40 years and over. Inaddition, a videotape of muscular relaxation techniqueswas made. A manual written in Chinese about the content of each class, was given to each subject whenhe/she attended. The experimental group showedsignificant improvement in the scores in the HamiltonDepression Scale, including the Somatic Subscale in the Hamilton Anxiety Scale. There was nosignificant improvement in the control group on any ofthe measures. Thus the study suggests the efficacy ofpsychoeducational classes in reducing symptoms ofdepression in non-patient community elderly. Other studiesare being conducted among Korean Americans and JapaneseAmericans in the United States, and also in the Orientamong Japanese elderly. 相似文献
97.
Excitotoxic injury profiles of low-affinity kainate receptor agonists in cortical neuronal cultures.
Neurotoxic profiles of putative agonists for low-affinity kainate subtypes of L-glutamate receptors (GluR5-7) were determined in cultured cortical neurones. Rank order of neurotoxic potency (microM): (S)-5-iodowillardiine (9) approximately = (2S,4R,6E)-2-amino-4-carboxy-7-(2-naphthyl)hept-6-enoic acid (LY339434, 11) > (2S,4R)-4-methylglutamate (33) > kainate (100) > (RS)-2-amino-3-(hydroxy-5-tert-butylisoxazol-4-yl)propanoic acid (ATPA, 360). Using ionotropic glutamate receptor antagonists, neurotoxicity induced by kainate, ATPA and (S)-5-iodowillardiine appeared to involve a GluR5-7 component, unlike LY339434 and (2S,4R)-4-methylglutamate. These putative GluR5-7 agonists exhibited complex excitotoxic profiles highlighting the importance of studying native glutamate receptors. 相似文献
98.
R P Nath R A Upton E T Everhart P Cheung P Shwonek R T Jones J E Mendelson 《Journal of clinical pharmacology》1999,39(6):619-623
Buprenorphine is an effective new treatment for opiate dependence. This study compared the bioavailability of buprenorphine from a tablet to that from a reference solution. Six men experienced with, but not dependent on, opiates (DSM-III-R) were each administered 7.7 mg of buprenorphine in liquid form and 8 mg in tablet form 1 week apart in a balanced crossover design. Plasma levels were measured by electron capture capillary gas chromatography (GC), and concentration-time curves were constructed. Pharmacokinetic data were analyzed by analysis of variance. The bioavailability from the tablet was approximately 50% that from the liquid and was not affected by saliva pH. Lower bioavailability from the tablet may be due to slow dissolution. 相似文献
99.
Andrew P. Cheung Yali F. Hallock B. Rao Vishnuvajjala Thuylinh Nguyenle Euphemia Wang 《Investigational new drugs》1999,16(3):227-236
Bryostatin 1 is currently in phase II clinical trial sponsored by the National Cancer Institute as an anticancer chemotherapeutic agent. Bryostatin 1 for injection was supplied in a dual pack containing a drug vial and a diluent vial and was manufactured by Ben Venue Laboratories, Inc (Bedford, OH). The stability and compatibility of the bryostatin 1-PET formulation, diluted to 1 and 10 ug/mL in saline and benzyl alcohol preserved saline, with polypropylene (PP) and polyvinyl chloride (PVC) bags at room temperature (27°C) were studied. All experiments were conducted in triplicate and analyses were performed using a validated, stability-indicating, high performance liquid chromatography (HPLC) assay.Bryostatin 1 solutions were compatible with PP bags. At both concentrations and with both salines, the bryostatin content remained unchanged during the 28-day storage period, benzyl alcohol concentration in the preserved saline solutions also remained relatively constant. In PVC bags, however, a decrease in bryostatin 1 concentrations without generation of decomposition products was observed at both dilutions and with both salines during the 28-day storage. A decrease in benzyl alcohol concentration in the preserved saline was also observed. While no diethylhexylphthalate (DEHP) leakage into the solution was observed in PP bags, DEHP leakage in PVC infusion bags was observed on day 2 of storage which increased with storage time and leveled off on day 6. The amount of DEHP leached into drug solution is dependent on the drug concentration. This study suggests bryostatin-PET formulation diluted with preserved saline can be used for long-term (4 week) intravenous administration using PP infusion bags, but not with PVC bags. 相似文献
100.
The autors presented two typical cases of patients who were infected with Propionibacterium acnes (P. acnes) after intraocular lens implantation. The patients were treated successfully by the removal of the intraocular lens and the residual lens capsule, and the administration of intravitreal vacomycin. The histopathology illustrated numerous prokaryote bacilli surrounding the lens material without inflammatory reaction. The thickened bacterial cell wall structure may relate to the resistance of P. acnes killing and degradation by the host neutrophils and macrophages. Complete removal of the lens material which may sequester the bacterial growth in the eye is important to eradicate P. acnes endophthalmitis. 相似文献