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51.
OBJECTIVE: To determine the neurodevelopmental outcome of prematurely born newborns with magnetic resonance imaging (MRI) abnormalities. STUDY DESIGN: A total of 89 prematurely born newborns (median age 28 weeks postgestation) were studied with MRI when stable for transport to MRI (median age, 32 weeks postgestation); 50 newborns were studied again near term age (median age, 37 weeks). Neurodevelopmental outcome was determined at 18 months adjusted age (median) using the Mental Development Index (Bayley Scales Infant Development II) and a standardized neurologic exam. RESULTS: Of 86 neonatal survivors, outcome was normal in 51 (59%), borderline in 22 (26%), and abnormal in 13 (15%). Moderate/severe MRI abnormalities were common on the first (37%) and second (32%) scans. Abnormal outcome was associated with increasing severity of white matter injury, ventriculomegaly, and intraventricular hemorrhage on MRI, as well as moderate/severe abnormalities on the first (relative risk [RR] = 5.6; P = .002) and second MRI studies (RR = 5.3; P = .03). Neuromotor abnormalities on neurologic examination near term age (RR = 6.5; P = .04) and postnatal infection (RR = 4.0; P = .01) also increased the risk for abnormal neurodevelopmental outcome. CONCLUSIONS: In premature newborns, brain abnormalities are common on MRI early in life and are associated with adverse neurodevelopmental outcome.  相似文献   
52.
Introduction Selective dorsal rhizotomy (SDR) is an effective treatment for lower extremity spasticity in cerebral palsy. Cortical organization in sensory cortex may be abnormal in cerebral palsy, and deafferentation is known to lead to cortical reorganization in many situations.Methods We used functional magnetic resonance imaging (fMRI) of hand sensory stimulation to determine if the partial deafferentation of the lower extremity sensory system, associated with SDR, led to any alterations in the cortical somatosensory representation for the upper limbs. Three patients with spastic diplegia were studied with blood oxygen level-dependent (BOLD)-fMRI before and after SDR. fMRI during tactile stimulation of the digits of the right hand was used to map hand somatosensory cortex. Comparison of the cortical maps devoted to the hand before and after SDR assessed for cortical reorganization following partial deafferentation of the lower extremity.Results In the one patient with upper extremity involvement, the hand sensory representation was markedly enhanced following SDR. In the other two patients, a normal pattern, but with diminished activity, was seen compared with preoperative findings. SDR for lower limb spastic diplegia does not lead to extensive reorganization of cortex dedicated to the representation of the upper limb. An essentially normal pattern of activation was seen both before and after SDR.Conclusion The relief of attention demands associated with spasticity may explain the modulation in intensity seen after SDR in the patients who exhibited no upper extremity involvement despite lower limb spasticity.  相似文献   
53.
Plantar ulceration is the most common serious disability occurring in patients of leprosy. Growth and emergence of innovative procedures in plastic surgery has greatly revolutionized the treatment of this highly frustrating problem. In the present study, a total of 40 leprosy patients were included. These ulcers were managed using different types of local superficial flaps (advancement, rotation, transposition and first toe web flap). Majority of ulcers healed within 4 weeks and patients were discharged within 6-8 weeks postoperatively. Patients were followed up for a period of 6 months to 3 years. Ulcers recurred in only 25% of all the ulcers operated upon and we observed that management of plantar ulcers by using appropriate local superficial plantar flaps is a viable option and worth trying in view of low incidence of recurrence and relatively shorter duration of hospital stay.  相似文献   
54.
Antigenic determinant analysis was carried out on VP3, one of major immunogenic proteins of Infectious bursal disease virus (IBDV) using computer algorithms. Altogether 17 peptides were synthesized for predicted putative regions and were tested for their reactivity with IBDV-positive polyclonal sera as well as with antisera to other common avian viruses to confirm specificity and to rule out cross reactivity. Of 17 peptides tested, three were selected and synthesized in multiple antigenic peptide (MAP) format. The immunization of rabbits with the three MAPs resulted in high humoral immune response. The purified antipeptide antibodies were screened against native IBDV antigen and the respective titers were determined. Out of the three antisera to MAPs that raised against the MAP3, spanning the amino acids (aa) 974-995 region on the VP3 protein had a very high titer (2048) and reacted specifically with IBDV. Thus, the antiserum to MAP3 detected native virus in enzyme-linked immunosorbent assay (ELISA), revealing the presence of a potential antigenic determinant on the C-terminus of the protein. This study proved that an antipeptide antibody could be used as a safe and specific tool for the diagnosis of IBD in chickens.  相似文献   
55.
Diffusion tensor imaging (DTI) was used to delineate early laminar organization of the cerebrum in two extremely premature infants imaged postnatally at estimated ages of 25 and 27 menstrual weeks. The diffusivity and anisotropy of the cortical plate, subplate zone, intermediate zone, subventricular and periventricular zones, and germinal matrix are examined. Automated segmentation of diffusion tensor images to reveal the laminar architecture of the developing human cerebrum is also demonstrated.  相似文献   
56.
Previous nutritional guidelines for people with diabetes focused on carbohydrate-based meal planning. Updated guidelines from Europe and North America reflect a more flexible approach to nutritional intervention. New aspects of these most recent recommendations include: (1) increased emphasis on the role of trained dietitians for educating people with diabetes; (2) greater individualization of dietary choices based on cultural, regional and personal preferences; (3) more flexibility for choosing between carbohydrate and monounsaturated fat consumption, but with limitations on intake of polyunsaturated fats (<10% of total energy); (4) broadened allowance of sucrose in the diet (up to 10% of total energy); and (5) greater recognition of physical activity as an important means to control weight and enhance general health. Expert guidelines vary regarding preferential intake of carbohydrates with lower glycemic indices.  相似文献   
57.
Vanadium--an element of atypical biological significance   总被引:9,自引:0,他引:9  
The biological image of the transition element vanadium ferments a great deal of contradiction-from toxicity to essentiality. Importance of this element as micro-nutrient is yet to be unequivocally accepted by biologists and biomedical scientists. In spite of toxicity, it seems interesting to analyze the different biological roles of the element. Vanadium compounds have been proven to be associated with various implications in the pathogenesis of some human diseases and also in maintaining normal body functions. Salts of vanadium interfere with an essential array of enzymatic systems such as different ATPases, protein kinases, ribonucleases and phosphatases. While vanadium deficiency accounts for several physiological malfunctionings including thyroid, glucose and lipid metabolism, etc., several genes are regulated by this element or by its compounds, which include genes for tumor necrosis factor-alpha (TNF-alpha), Interleukin-8 (IL-8), activator protein-1 (AP-1), ras, c-raf-1, mitogen activated protein kinase (MAPK), p53, nuclear factors-kappaB, etc. All these seem to be not far from its recognition as an element of pharmacological and nutritional significance, which is revealed through its increasing therapeutic uses in diabetes. Vanadium is also emerging as a potent anti-carcinogenic agent. This review summarizes the developments related to vanadium biology as a whole by analyzing the general biochemical functions of vanadium.  相似文献   
58.
BACKGROUND AND PURPOSE: Wallerian degeneration, the secondary degeneration of axons from cortical and subcortical injury, is associated with poor neurologic outcome. Since diffusion-weighted (DW) imaging is sensitive to early changes of cytotoxic edema, DW imaging may depict the acute injury to descending white matter tracts that precedes Wallerian degeneration; this injury is not visible on conventional CT or MR images in the maturing human brain. METHODS: Two neuroradiologists retrospectively analyzed clinical MR images in six children (aged 3 days to 5 months) with DW findings consistent with acute injury of the descending white matter tract due to territorial anterior or middle cerebral artery infarction. In five patients, images were obtained as a part of routine clinical evaluation. The remaining patient was a part of a prospective study of brain injury. Imaging findings were correlated with clinical outcomes. RESULTS: In all six patients, DW imaging performed 2-8 days after the onset of ischemia depicted injury to the descending white matter tract ipsilateral to the territorial infarct. Conventional MR images of the ipsilateral descending white matter tracts were abnormal in three patients. In all five patients for which follow-up results were available, the presence of DW changes was correlated with persistent neurologic disability. CONCLUSION: As shown in this retrospective analysis, DW imaging can depict acute injury to the descending white matter tract in neonates and infants, when conventional MR imaging may show normal findings. These DW findings likely precede the development of Wallerian degeneration, and they may portend a poor clinical outcome.  相似文献   
59.
A case of follicular variant of papillary thyroid carcinoma presenting with a right maxillary mass is described. This is perhaps the first instance of maxillary metastasis from papillary thyroid carcinoma.  相似文献   
60.
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