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31.
BACKGROUND: In Nigeria, systemic hypertension is the commonest noncommunicable disease, and public awareness about hypertension and its determinants is poor. This study aims to assess the knowledge and level of awareness of the disease among hypertensive patients attending the medical outpatient clinic of Olabisi Onabanjo University Teaching Hospital (OOUTH). METHODOLOGY: Hypertensive patients who attended the medical outpatient clinic during the one-year study period and gave their consent were recruited into the study. Response to a questionnaire on various aspects of hypertension was analyzed using the STATA for Windows software. RESULTS: There were 254 hypertensive patients, of which 111 were males and 143 were females, giving a male: female ratio of 1:1.3. The mean age (SD) of the patients was 51 years +/- 12.2; 52.4% of the participants were aware that hypertension was the commonest noncommunicable disease in Nigeria. About one in 10 patients (11.4%) was aware that "nil symptom" is the commonest symptom of hypertension, while 37% were not aware that hypertension could cause renal failure. Only about one-third (35.4%) of the patients knew that hypertension should ideally be treated for life, while 58.3% believed that antihypertensive drugs should be used only when there are symptoms. The remaining 6.3% believed that the treatment of hypertension should be for periods ranging from two weeks to five years but not for life. CONCLUSION: This study has demonstrated inadequate knowledge of hypertension in patients with hypertension in our study population. Conscious efforts should be made and time set aside to health educate hypertensive patients. Organization of "hypertensive club or society" could be encouraged. These will reduce dissemination of false or inaccurate information by hypertensive patients to the public and its attendant dangers.  相似文献   
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33.
BACKGROUND: Atherosclerosis is considered to be a chronic inflammatory disorder. Several large-scale clinical studies demonstrate that markers of inflammation, such as high-sensitivity C-reactive protein (hsCRP), fibrinogen, and soluble CD40 ligand, are potent and independent predictors of vascular risk. HYPOTHESIS: The study was undertaken to investigate the effect of increasing the statin dose from conventional to aggressive treatment on lipids levels, inflammation, and endothelial function in patients with coronary artery disease (CAD). METHODS: We randomized 97 patients to either 20 mg simvastatin or 80 mg atorvastatin. Plasma levels of lipids, hsCRP, fibrinogen, soluble adhesion molecules, and nitric oxide-total were analyzed at baseline and after 6 months of treatment. RESULTS: Lipid values were significantly reduced in both treatment groups, but with significantly greater reduction in the aggressively treated group. Furthermore, aggressive statin treatment significantly decreased hsCRP and fibrinogen, while only small reductions were seen in the conventionally treated group, resulting in significant differences between the two treatment groups (p < 0.001). Nitric oxide-total increased significantly in both treatment groups, although the increase was more pronounced in the aggressively treated group (22.6 vs. 15.6%). CONCLUSION: Aggressive statin treatment significantly improved lipid status and reduced markers of inflammation and improved endothelial function compared with conventional treatment in patients with CAD. No interaction was observed, and high-dose treatment did not offer additional benefit compared with standard-dose treatment with respect to soluble adhesion molecules.  相似文献   
34.
Several brain imaging studies have identified a region of fusiform gyrus (FG) that responds more strongly to faces than common objects. The precise functional role of this fusiform face area (FFA) is, however, a matter of dispute. We sought to distinguish among three hypotheses concerning FFA function: face specificity, individuation, and expert individuation. According to the face-specificity hypothesis, the FFA is specialized for face processing. Alternatively, the FFA may be specialized for individuating visually similar items within a category (the individuation hypothesis) or for individuating within categories with which a person has expertise (the expert-individuation hypothesis). Our results from two experiments supported the face-specificity hypothesis. Greater FFA activation to faces than Lepidoptera, another homogeneous object class, occurred during both free viewing and individuation, with similar FFA activation to Lepidoptera and common objects (Experiment 1). Furthermore, during individuation of Lepidoptera, 83% of activated FG voxels were outside the face FG region and only 15% of face FG voxels were activated. This pattern of results suggests that distinct areas may individuate faces and Lepidoptera. In Experiment 2, we tested Lepidoptera experts using the same experimental design. Again, the results supported the face-specificity hypothesis. Activation to faces in the FFA was greater than to both Lepidoptera and objects with little overlap between FG areas activated by faces and Lepidoptera. Our results suggest that distinct populations of neurons in human FG may be tuned to the features needed to individuate the members of different object classes, as has been reported in monkey inferotemporal cortex, and that the FFA contains neurons tuned for individuating faces.  相似文献   
35.
Digit representation is more than just hand waving   总被引:1,自引:0,他引:1  
Lip-reading and interpreting hand gestures help provide nonverbal information that aids speech comprehension in noisy environments and places emphasis on certain key utterances. In this fMRI study, we examined if viewing the similar semantic information presented by either finger movements or lip movements was processed by common or discrete brain regions. Subjects viewed videos of a hand conveying number information via finger movements and a face whose lip movements conveyed the same numerical information. Control stimuli consisted of meaningless finger and lip movements. Lip-reading numbers activated left posterior superior temporal sulcus (STS), while identifying numbers presented by fingers activated the intraparietal region (IPR) bilaterally. Conjunction analysis highlighted common activation in right IPR to numbers presented via fingers and lips. Our data indicate that left hemisphere decodes human movements conveying semantic information, although the specific brain region that is engaged may depend on the body part that is moving.  相似文献   
36.
The selective serotonin reuptake inhibitors (SSRIs) and cocaine bind to the neural serotonin (5-HT) transporter (SERT) and thus inhibit presynaptic reuptake of 5-HT and elevate its concentration in the synaptic cleft. Cocaine also binds to the dopamine transporter (DAT) and to the noradrenaline transporter (NET) and inhibits presynaptic reuptake of dopamine and noradrenaline. SERT, DAT, and NET belong to the sodium/neurotransmitter symporter family, which is predicted to have a molecular structure with 12 transmembrane alpha-helices (TMHs) and intracellular amino- and carboxy terminals. We used an electron density projection map of the Escherichia coli Na+/H+ anti-porter, and site-directed mutagenesis data on DAT and SERT to construct 3-dimensional molecular models of SERT, DAT and NET. These models were used to simulate the molecular interaction mechanisms of the SSRI, S-citalopram, its less potent enantiomer, R-citalopram and of cocaine with the transporters. In the SERT model, a single amino acid (Tyr95) in TMH1 determined the transporter selectivity of S-citalopram for SERT over DAT and NET. A dipole-dipole interaction was formed between the hydroxy group of Tyr95 in SERT and the nitril group of S-citalopram, but could not be formed by S-citalopram in DAT and NET where the corresponding amino acid is a phenylalanine. The lower binding affinity of R-citalopram may be due to sterical hindrance at the binding site. The tropane ring of cocaine interacted with Tyr95 in SERT and with the corresponding phenylalanines in NET and DAT. This may explain why cocaine, but not S-citalopram, has high binding affinity to all three transporters.  相似文献   
37.
Background : The Zuckerkandl’s tubercle (ZT) of the thyroid gland is a well‐described anatomical landmark, but few studies have clearly defined its association with pressure symptoms. Methods : Sixty‐six consecutive patients who had primary thyroid surgery were prospectively included in the present study between late January and early August 1998. Results : A total of 96 capsular dissections were performed at thyroid surgery. Grades two and three ZT were recognized in 77 (80.2%) dissections. In general 49 (63.6%) of them were associated with significant pressure symptoms. In 43 (87.8%) of the dissections with pressure symptoms, grade 3 ZT was observed (mean weight of goitre: 154.8 g). Interestingly in this group, 16 (37.2%) patients with pressure symptoms had a goitre that was < 100 g and in one patient it was only 21 g. Conclusions : The pressure symptom of the thyroid gland does not always appear to be due to the large size of the goitre. In a relatively small‐size goitre the ZT may cause significant pressure symptoms. Observations in the present study supported a strong association of enlarged ZT with pressure symptoms. We believe this is unlikely to be simply a coincidence but rather a consequence of the enlarged tubercle. Nonetheless a prospective randomized study is called for to allow meaningful and objective evidence to be drawn.  相似文献   
38.
Objective To identify probable factors underlying inadequacy of medication history information recorded in patients' case notes by physicians in an ambulatory tertiary care setting in Nigeria. Method A cross‐sectional survey was conducted, with a pre‐tested 25‐item questionnaire, of 93 physicians at the nine medical units in the Department of Medicine at University College Hospital, Ibadan, Nigeria. Key findings The overall response rate was 79.6% (74/93), and the usable rate was 75% (70/93). A majority of physicians opined that a detailed medication history is an essential component of optimal and patient‐specific care; and they were able to identify correctly the key components of a detailed medication history. However, about 60% of physicians opined that the adequacy of medication history documented by them is affected by heavy workload due to the large number of patients to which they attend. The majority (75%) of physicians also considered detailed documentation of patient medical history to be more important than medication history. Conclusions Physicians' heavy workload, due to the large number of patients, and their belief that medical history is more important than medication history, appear to be the probable factors underlining the inadequacy of physician‐acquired medication history in a developing sub‐Saharan tertiary care setting.  相似文献   
39.
亲血栓性靶向超声造影剂的鉴定及体外寻靶实验研究   总被引:5,自引:3,他引:5  
目的 制备亲血栓性靶向超声造影剂,探讨其体外寻靶的特点和规律。方法 在自制的白蛋白氟碳超声造影剂的基础上,采用交连法将带有荧光标记的6-肽(FITC-KV-6)与自制的白蛋白氟碳微泡结合,制备血栓靶向微泡造影剂。体外实验分3组,A组:将带有FITC-KV-6的造影剂滴加于健康人新鲜血凝块上,普通光镜和荧光显微镜下观察微泡与血块的黏附情况;B组对照:普通白蛋白氟碳造影剂;C组对照:6-肽阻断实验。结果 靶向微泡荧光免疫染色实验为阳性,对照组为阴性。体外实验显示,A组:微泡在血凝块外围形成一条凝聚带,并顺着网格状的纤维素带延伸到血块内部,而2个对照组均未见微泡与血凝块的结合。结论 采用交连法可制备亲血栓性靶向白蛋白超声造影剂;该造影剂微泡在体外能与人新鲜血凝块高效特异结合。  相似文献   
40.
Aging‐related tau astrogliopathy (ARTAG) is defined by the presence of two types of tau‐bearing astrocytes: thorn‐shaped astrocytes (TSAs) and granular/fuzzy astrocytes in the brain of old‐aged individuals. The present study is focused on TSAs in rare forms of ARTAG with no neuronal tau pathology or restricted to entorhinal and transentorhinal cortices, to avoid bias from associated tauopathies. TSAs show 4Rtau phosphorylation at several specific sites and abnormal tau conformation, but they lack ubiquitin and they are not immunostained with tau‐C3 antibodies which recognize truncated tau at Asp421. Astrocytes in ARTAG have atrophic processes, reduced glial fibrillary acidic protein (GFAP) and increased superoxide dismutase 2 (SOD2) immunoreactivity. Gel electrophoresis and western blotting of sarkosyl‐insoluble fractions reveal a pattern of phospho‐tau in ARTAG characterized by two bands of 68 and 64 kDa, and several middle bands between 35 and 50 kDa which differ from what is seen in AD. Phosphoproteomics of dissected vulnerable regions identifies an increase of phosphorylation marks in a large number of proteins in ARTAG compared with controls. GFAP, aquaporin 4, several serine‐threonine kinases, microtubule associated proteins and other neuronal proteins are among the differentially phosphorylated proteins in ARTAG thus suggesting a hyper‐phosphorylation background that affects several molecules, including many kinases and proteins from several cell compartments and various cell types. Finally, present results show for the first time that tau seeding is produced in neurons of the hippocampal complex, astrocytes, oligodendroglia and along fibers of the corpus callosum, fimbria and fornix following inoculation into the hippocampus of wild type mice of sarkosyl‐insoluble fractions enriched in hyper‐phosphorylated tau from selected ARTAG cases. These findings show astrocytes as crucial players of tau seeding in tauopathies.  相似文献   
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