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排序方式: 共有238条查询结果,搜索用时 15 毫秒
81.
G Iannucci M Villani F Giacopello M Giordano A P Cangelosi R Ciardo F M Di Paolo A Sciacca G Baciarello 《Giornale italiano di cardiologia》1992,22(3):281-290
BACKGROUND: Patients with hypertrophic cardiomyopathy are at increased risk of sudden death. Recently it has been investigated whether late potentials can be useful markers of that risk in such patients, with discordant results. The aim of our study was to detect a correlation, if any, between late potentials, ventricular tachycardia and the hypertrophy extension. METHODS: Twenty-five patients were enrolled, 19 males and 6 females, mean age 40.40 +/- 15.02 years. Each underwent 24h Holter monitoring, averaged ECG, M-Mode and 2-D Echo. The hypertrophy was considered extensive (septum and free wall) or non extensive (septum and/or apex). RESULTS: Late potentials of a mean duration of 37 +/- 14.83 ms were recorded in 5/7 patients with documented ventricular tachycardia vs in none of the non tachycardia group. Sensibility was 100%, specificity 71% and predictive value 100%. Late potentials were present in 8.3% of patients with non extensive and in 30.8% of patients with extensive hypertrophy (p = NS). CONCLUSIONS: From our data it seems that extensive hypertrophy is present in about half of patients with hypertrophic cardiomyopathy, and this roughly correlates with a more frequent ventricular tachycardia and with late potentials. Furthermore, late potentials are strictly related to the incidence of ventricular tachycardia in this disease, just as in ischemic heart disease or in idiopathic dilated cardiomyopathy. The small number of our cases may not be sufficient to reach a significant statistical correlation between late potentials and hypertrophy, but we believe that the trend is very promising. 相似文献
82.
ObjectiveTo evaluate the effect of extract of Murraya paniculata Linn. (Family – Rutaceae) on blood glucose, cholesterol, triglyceride and lipid level and antioxidant status in alloxan induced diabetic and non-diabetic rats.MethodsHydro-alcoholic extract of M. paniculata leaves (100, 200 and 400 mg/kg) was administered orally for 14 days and its effect on blood glucose, cholesterol, triglycerides and lipid level were estimated in serum. Liver free radical (lipid peroxidation, LPO) and antioxidant (Super oxide dismutase, SOD; catalase, CAT; and reduced glutathione peroxidase, GPx) were also measured after 14 days treatment with extract. Glucose level in non-diabetic rats was estimated after 21 days treatment with M. paniculata extract.ResultsOral administrations of M. paniculata extract (100, 200 and 400 mg/kg) for 14 days significantly reduced the levels of blood glucose, cholesterol, and triglyceride and lipid level. Liver free radical (LPO) significantly reduced and antioxidants (SOD, CAT and GPx) status significantly increase after 14 days treatment of extract in diabetic rats. M. paniculata 200 and 400 mg/kg significantly decrease glucose level in non-diabetic rats after 21 day and caused hypoglycemia in normal rats.ConclusionsM. paniculata leaves extract posses hypoglycemic effect in oxidative stress condition and also in non-diabetic condition. Hypoglycemic action may be by potentiating of the insulin effect by increasing either the pancreatic secretion of insulin from beta cells of islets of langerhans or its release from the bound form. M. paniculata could be a potential source of hypoglycemic agent with antioxidant properties. 相似文献
83.
Magnetization transfer and diffusion tensor MR imaging of acute disseminated encephalomyelitis 总被引:6,自引:0,他引:6
Inglese M Salvi F Iannucci G Mancardi GL Mascalchi M Filippi M 《AJNR. American journal of neuroradiology》2002,23(2):267-272
BACKGROUND AND PURPOSE: Patients with acute disseminated encephalomyelitis (ADEM) and multiple sclerosis (MS) have a similar pattern of abnormalities on conventional MR images. We used magnetization transfer and diffusion tensor MR imaging to quantify normal-appearing brain tissue and cervical cord disease in patients with ADEM and to compare findings with those in healthy volunteers and patients with MS. METHODS: Brain dual-echo, T1-weighted magnetization transfer, and diffusion tensor images were obtained in eight patients with ADEM, in 10 patients with MS, and in 10 healthy volunteers. Fast short-tau inversion recovery, T1-weighted, and magnetization transfer cervical cord images were also obtained. We identified lesions on the images and quantified their volumes. We performed histogram analysis of the magnetization transfer ratio (MTR) and average mean histogram analysis of the diffusivity (D) in normal-appearing brain tissue and MTR in the cervical cord. RESULTS: Histogram analysis of normal-appearing brain tissue in patients with MS showed significantly lower MTRs and peak positions and significantly higher D averages compared with those in patients with ADEM. Patients with MS had significantly lower MTRs and D peak heights and significantly higher average D compared with those in healthy volunteers. Between patients with ADEM and control subjects, normal-appearing brain tissue MTR and D histogram metrics did not differ significantly. Cervical cord MTRs did not differ between control subjects and patients with ADEM, whereas the average MTR and histogram peak position was significantly lower in patients with MS than in the other groups. CONCLUSION: Outside the acute phase of disease and as opposed to what happens in MS, the normal-appearing brain tissue and cervical cord in patients with ADEM are spared in the pathologic process. 相似文献
84.
Underuse of screening mammography by family physicians 总被引:3,自引:0,他引:3
Although the American College of Radiology, the National Cancer Institute, and the American Cancer Society recommend screening mammography for women more than 40 years old, there is little compliance with these recommendations. Primary-care physicians are often reluctant to refer patients for the procedure, whereas the patients are usually willing to undergo the procedure. This survey documents the underuse of screening mammography by family physicians who are members of the Michigan Academy of Family Physicians. The underuse of mammography by this physician sample was due to two main factors: The physicians perceived far more disadvantages than advantages with mammography and perceived problems (with, e.g., equipment, effectiveness, and patient acceptance) as pervasive. To change the attitudes and referral behavior of family physicians, one must take into account the specific, negative perceptions of the procedure and place an emphasis on the initial referral, since subsequent referrals are easier to implement. 相似文献
85.
86.
Low-dose high-resolution CT of lung parenchyma 总被引:15,自引:0,他引:15
87.
Cervical radiculopathy: value of oblique MR imaging 总被引:2,自引:0,他引:2
Eighteen patients with cervical radiculopathy were entered into a prospective study to compare the accuracy of surface coil magnetic resonance (MR) imaging with that of metrizamide myelography and computed tomography (CT) with metrizamide. All MR studies included tailored axial and oblique images as well as routine sagittal images. All imaging studies were evaluated for topography and type of disease. Nine of 18 patients subsequently underwent cervical surgery with an anterior interbody approach at 11 levels. The surface coil MR findings concerning disease topography and type concurred with the surgical findings at nine of 11 levels (82%). At three levels, the oblique view added important information not available on the sagittal images or clarified changes seen on the axial images. Metrizamide myelography with CT metrizamide myelography had findings concurrent with surgical findings at ten of 11 levels (91%). 相似文献
88.
89.
KW Miskowiak J Macoveanu MB Jørgensen CV Ott MM Støttrup HM Jensen A Jørgensen CJ Harmer OB Paulson HR Siebner LV Kessing 《European neuropsychopharmacology》2018,28(8):915-924
Electroconvulsive therapy (ECT) is the most effective treatment for severe depression but its neurocognitive mechanisms are unclear. This randomized, sham-controlled functional magnetic resonance imaging (fMRI) study explored the effects of a single ECT on neural response to affective pictures. Twenty-seven patients with major depressive disorder were randomized to a single active ECT (N?=?15) or sham (N?=?12) session in a double-blind, parallel-group design. On the following day, patients underwent fMRI during which they viewed pleasant, unpleasant and neutral pictures and performed a free recall test after the scan. Mood symptoms were assessed before ECT/sham and at the time of fMRI. Subsequently, all patients continued active ECT as usual. Mood symptoms were reassessed after six active ECT sessions. A single ECT vs. sham session reduced neural response to unpleasant vs. pleasant pictures in the medial prefrontal cortex, a region showing greater response in the more depressed patients. This effect occurred in the absence of between-group differences in picture recall, mood symptoms or concomitant medication. In conclusion, modulation of medial prefrontal hyper-activity during encoding of negative affective information may be a common mechanism of distinct biological depression treatments. 相似文献
90.