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61.
We investigated the effect of vestibular stimulation on the lateralization of dichotic sound by cold-water irrigation of the external auditory canal in human subjects. Subjects adjusted the interaural level difference of the auditory stimulus to the subjective median plane of the head. In those subjects in whom dizziness and nystagmus indicated sufficient vestibular stimulation, these adjustments were significantly shifted toward the cooled ear compared with the control condition (irrigation with water at body temperature); i.e., vestibular stimulation induced a shift of the sound image toward the nonstimulated side. The mean magnitude of the shift was 7.3 dB immediately after vestibular stimulation and decreased to 2.5 dB after 5 min. As shown by an additional control experiment, this effect cannot be attributed to a unilateral hearing loss induced by cooling of the auditory periphery. The results indicate the involvement of vestibular afferent information in the perception of sound location during movements of the head and/or the whole body. We thus hypothesize that vestibular information is used by central-nervous mechanisms generating a world-centered representation of auditory space.  相似文献   
62.
The aim of this study was to determine the efficacy of long-term oral β -carotene supplementation for correcting impaired β -carotene status in cystic fibrosis patients. Thirty-five patients (2.3-30.5 years of age) with coefficients of fat absorption of 46-96% (median 88%) received β -carotene 0.5 mg/kg daily and were followed over a 16-month treatment period. Baseline plasma β -carotene concentrations in patients (meanSD, 0.090.06 μ mol/1) were significantly lower than those of age-matched controls (0.860.56 μ mol/1) ( p < 0.0001). Concentrations increased rapidly and reached a plateau at or before 3 weeks that was maintained throughout the study period. Values obtained at 3 weeks (0.890.64 μ mol/1) were significantly higher ( p < 0.0001) than those at baseline and did not differ from controls. Plasma retinol and α -tocopherol concentrations increased during the observation period, but remained within normal ranges. Plasma retinyl palmitate, which was below the detection limit in all but one patient at baseline, did not increase. Thus oral β -carotene supplementation is effective and normalizes β -carotene status of cystic fibrosis patients without evidence of significant side effects. β -Carotene, cystic fibrosis, LDL-cholesterol, oral supplementation, retinol, α-tocopherol  相似文献   
63.
A case of malignant granular cell tumour of the sciatic nerve is presented. Computed tomography demonstrated iso-density with muscle and minimal enhancement. Magnetic resonance demonstrated T1 isointensity with muscle with marked enhancement, and isointensity with fat on proton and T2 images. Pathological evidence is presented for its probable Schwann cell histogenesis.  相似文献   
64.
The clinical incidence of lymphoedema of the arm in breast cancer patients was studied before and after general mammography screening in the country of jönköping, Sweden. There was a significant decrease of incidence of lymphoedema from 15% in 1983 to 8% in 1988. Clinical and pathological therapy data have been analysed in relation to lymphoedema. Significant factors contributing to lymphoedema were the number of lymph nodes examined and the number of pathologically positive lymph nodes. A higher proportion of patients receiving post-operative radiotherapy to the axilla developed lymphoedema, compared with those with surgery alone.
A comparison between the two groups is impossible due to the fact that post-operative radiotherapy was prescribed only to patients with pathologically positive lymph nodes.  相似文献   
65.
66.
Prognosis of contraversive pushing   总被引:1,自引:0,他引:1  
Stroke patients with ‘pusher syndrome’ actively push away from the non-hemiparetic side leading to a loss of postural balance and falling towards the paralysed side. The behaviour is due to an altered perception of the body's orientation in relation to gravity. Here, we studied the prognosis of the disorder. Twelve pusher patients first investigated immediately after the stroke were re-examined 6 months later. Pusher symptoms had nearly completely recovered. The aim for physiotherapy of patients with contraversive pushing thus is to shorten the period of necessary treatment and enable earlier discharge from residential care. Received: 30 November 2001, Received in revised form: 15 March 2002, Accepted: 18 March 2002  相似文献   
67.
The effect of passive whole-body tilt in the frontal plane on the lateralization of dichotic sound was investigated in human subjects. Pure-tone pulses (1 kHz, 100 ms duration) with various interaural time differences were presented via headphones while the subject was in an upright position or tilted 45 degrees or 90 degrees to the left or right. Subjects made two-alternative forced-choice (left/right) judgements on the intracranial sound image. During body tilt, the auditory median plane of the head, computed from the resulting psychometric functions, was always shifted to the upward ear, indicating a shift of the auditory percept to the downward ear, that is, in the direction of gravitational linear acceleration. The mean maximum magnitude of the auditory shift obtained with 90 degrees body tilt was 25 micro s. On the one hand, these findings suggest a certain influence of the otolith information about body position relative to the direction of gravity on the representation of auditory space. However, in partial contradiction to previous work, which had assumed existence of a significant 'audiogravic illusion', the very slight magnitude of the present effect rather reflects the excellent stability in the neural processing of auditory spatial cues in humans. Thus, it might be misleading to use the term 'illusion' for this quite marginal effect.  相似文献   
68.
OBJECTIVE: To investigate opportunities for, and types of decision making in the general practice (primary care) consultation, and examine differences in skills of those doctors who are successful at meeting their patients' preferences and those who are less successful. DESIGN: Observation study of doctor-patient consultations in general practice. PARTICIPANTS: Patients attending for routine appointments in 12 general practice surgeries across Oxfordshire. METHODS: A total of 212 doctor-patient consultations were video-recorded. The patients involved completed a questionnaire to elicit their perceptions of how decisions were made. The video-taped recordings were coded with a new instrument, the Evidence Based Patient Choice Instrument (EBPCI), to classify the number and type of decision-making opportunities arising during each consultation. A total of 149 recordings were coded using the Oxbridge Rating Scale to assess the doctors' consultation styles. RESULTS: There was a range of decision-making opportunities in addition to those involving medical treatment. With the exception of 'fitness for work', decisions were generally 'doctor led'. There was only moderate agreement between patient perceptions of their level of involvement in decision making and the objective ratings using the EBPCI. There was wide variation in the ability of doctors to meet their patients' preferences for involvement. CONCLUSIONS: There are many decisions made in primary care consultations, in addition to those about medical treatments, in which patients could be involved to a greater extent than they currently are. Some doctors are significantly better than others at meeting different patients' preferences for their decision-making role. Patients' perceptions of shared decision making appears to be influenced by the doctors' general consultation skills.  相似文献   
69.
Summary: A case report is described in which abdominal pregnancy was misdiagnosed by ultrasound scanning as a pregnancy within a horn of a bicornuate uterus. Two serum alpha fetoprotein (SAFP) results were greatly elevated and an amniocentesis was performed, the liquor alpha fetoprotein (LAFP) and karyotype were normal. Elective Caesarean section was performed at 38 weeks for a persistent transverse lie and an abdominal pregnancy was found. The outcome was excellent for both the mother and child.
This is the first reported case of amniocentesis and measurement of LAFP in an abdominal pregnancy and confirms abdominal pregnancy as a rare cause of an elevated SAFP.  相似文献   
70.
The main purpose of this study was to compare rectal and axillary temperature measurements in African children. Altogether 573 sick children were seen in an outpatient setting in rural West Africa. Rectal and axillary temperatures were measured and the parent or guardian was asked if they thought that the child had a raised body temperature. Normal ranges were defined from an age matched population of 203 healthy children. A raised axillary temperature predicted a raised rectal temperature with a sensitivity of 98% and a specificity of 88%. The parents' impression that their child had a fever was a less sensitive (89%) and less specific (59%) indicator of raised rectal temperature. A raised axillary temperature is a good screening test for a raised rectal temperature in African children.  相似文献   
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