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91.
Magnetic resonance imaging in the study of the lithium-pilocarpine model of temporal lobe epilepsy in adult rats 总被引:3,自引:0,他引:3
PURPOSE: In temporal lobe epilepsy, it remains to be clarified whether hippocampal sclerosis is the cause or the consequence of epilepsy. We studied the temporal evolution of the lesions in the lithium-pilocarpine model of epilepsy in the rat with magnetic resonance imaging (MRI) to determine the progressive morphologic changes occurring before the appearance of chronic epilepsy. METHODS: MRI was performed on an MR scanner operating at 4.7 T. We followed the evolution of lesions using T(2)- and T(1)-weighted sequences before and after the injection of gadolinium from 2 h to 9 weeks. RESULTS: At 2 h after status epilepticus (SE), a blood-brain barrier breakdown could be observed only in the thalamus; it had disappeared by 6 h. At 24 h after SE, edema was present in the amygdala and the piriform and entorhinal cortices together with extensive neuronal loss; it disappeared progressively over a 5-day period. During the chronic phase, a cortical signal reappeared in all animals; this signal corresponded to gliosis, which appeared on glial fibrillary acidic protein (GFAP) immunohistochemically stained sections as hypertrophic astrocytes with thickened processes. In the hippocampus, the correlation between histopathology and T(2)-weighted signal underscored the progressive constitution of atrophy and sclerosis, starting 2 days after SE. CONCLUSIONS: These data show the reactivity of the cortex that characterizes the initial step leading to the development of epilepsy and the late gliosis that could result from the spontaneous seizures. Moreover, it appears that hippocampal sclerosis progressively worsened and could be both the cause and the consequence of epileptic activity. 相似文献
92.
Psoriasis is one of the most common chronic skin diseases. The author presented results from a qualitative study focusing on patients with severe psoriasis in an acute phase and their experience of living with the disease. Twenty-two hospitalized patients with psoriasis were interviewed in depth. The interviews were consecutively analyzed according to grounded theory methodology. Bodily suffering emerged as a core variable in the data. Bodily suffering includes the following categories: the visible body, staying on an even keel, coping with an all-consuming disease, and social vulnerability. The results of this study indicate that the criterion for the management of soriasis should be the patients' own perception of the consequences of the disease. 相似文献
93.
Lawson ML Crewther SG Blume-Tari A Guminsky M Perdikeas N Roebuck G Simmonds S Crewther DP 《Clinical & experimental ophthalmology》2002,30(3):221-226
The concept of global precedence, which suggests that the global aspect of a scene is processed more rapidly than local details, was examined using the attentional blink paradigm. Eighteen adult subjects observed multiple sequences of complex global-local letter figures to see whether the attentional blink duration would be affected by the visual angle size of the stimulus. Within each sequence, the subject was directed to identify either a global or local red target letter and to detect whether a global or local probe letter (X) was presented in the sequence following the target letter. Stimuli were presented at three different sizes. Results showed significantly higher probe detection rates for global probes than for local at small stimulus sizes. However, using large stimulus sizes, mean correct probe detection was significantly higher in conditions requiring local attention compared to global. No significant difference in probe detection performance was observed between global and local conditions at medium stimulus sizes. The results suggest that the rate of visual information processing varies according to the visual angle of the particular information. The results support the suggestion that the precedence of information is an important factor in the temporal processing of global-local information. 相似文献
94.
It is important to have a simple. accurate method for recording eye movements. Of the two popular approaches commonly adopted, electro-oculography (EOG) and infrared oculography (IROG), IROG is often accepted as the more accurate, and it is the method that is currently used most frequently to examine eye movements in schizophrenia. This study investigated whether the misclassification of blinks as saccades affects saccade rates when the presence of a blink is determined using only IROG recordings of eye position. Both vertical electro-oculography (VEOG), which can be used to objectively identify blinks, and IROG were recorded while 17 schizophrenia patients and 19 healthy controls were presented with sinusoidal stimuli. Of the blinks identified with the VEOG for the total group of participants, a substantial number (37%) were misclassified as catch-up and anticipatory saccades when only the IROG was used. Furthermore, in the schizophrenia group, but not in the healthy control group, the use of the IROG led to a significant misclassification of blinks as anticipatory saccades. Therefore, when IROG alone is used to identify blinks, the misclassification of blinks as saccades is likely to introduce measurement error into estimates of saccade rates, particularly estimates of anticipatory saccade rates in schizophrenia patients. 相似文献
95.
Egger G Burda A Glasner A 《Virchows Archiv : an international journal of pathology》2001,438(4):394-397
We have developed an improved method for measuring the filamentous (F) actin content of human blood polymorphonuclear leukocytes (PMNs). The essential feature of the method is the immediate fixation of the F-actin cytoskeleton. Fresh whole blood (100 microliters) is shock-cooled by the addition of 1.0 ml of a mixture of 18.75% glycerol and 5% formaldehyde in phosphate buffer pre-cooled to -8 degrees C and subsequently fixed at 4 degrees C for 15 min. After lysis in distilled water and removal of the red blood cells by centrifugation, the F-actin cytoskeleton of the PMNs is stained with fluorescein isothiocyanate (FITC)-phalloidin and quantified by means of flow cytometry. In healthy test subjects, PMN stimulation by the chemotactic peptide formyl-methionyl-leucyl-phenylalanine (FMLP) for 20 s resulted in a significantly increased F-actin assembly, while in patients with multiple organ failure, two subpopulations arose: one with greater F-actin content and a second with lower F-actin content in comparison with the unstimulated blood sample. This simple and fast method may be a useful tool in basic and clinical research. 相似文献
96.
Rustøen T Wahl AK Hanestad BR Gjengedal E Moum T 《Heart & lung : the journal of critical care》2004,33(2):111-118
PURPOSE: Hope was evaluated in Norwegian patients with cystic fibrosis (CF). PARTICIPANTS: The subjects were 87 Norwegian adults with CF and a control group of 1020 from the general population (GP). METHODS: Subjects completed a questionnaires that included the Herth Hope Index and demographic variables. Data on health-related variables were collected for the CF group. RESULTS: The mean age of the CF patients was 29 years (range 18-54). Almost 50% had a forced expiratory volume for one second percent predicted (FEV1%) below 50%, and 21% reported perceiving being in a bad phase of the disease. The CF patients reported lower (poorer) levels of hope than the GP sample, especially for the item scared about the future. However, they scored higher on inner strength and were younger, more often living alone, unmarried, not in paid work, but with similar educational levels. Levels of hope increased with increasing age in the CF patients but decreased for the GP subjects. The health variable that most affected hope in the CF sample was pulmonary function, not the presence of asthma or chronic lung infections. CONCLUSIONS: Persons growing up with CF experience many challenges. CF patients expressed slightly lower levels of hope and were more scared of the future. They scored higher on inner strength than the general population. 相似文献
97.
Genetics for targeting disease prevention: diabetes 总被引:1,自引:0,他引:1
Newell AM 《Primary care》2004,31(3):743-66, xii
This article provides an overview of current thinking regarding genetics and diabetes (type 1, type 2, and gestational diabetes mellitus),including a selective look at a few implicated gene variants. This article explores how this information might be applied in current and future clinical practice to (1) predict who is at risk for diabetes and its complications, (2) identify and intervene to prevent or delay the development of diabetes in persons at risk, (3) identify patients with diabetes in an early stage and intervene to prevent later complications,and (4) individualize therapy for patients with diabetes to improve outcomes. The article concludes with some general thoughts about genetics and diabetes prevention in the future. 相似文献
98.
Temporal patterns of the cerebral inflammatory response in the rat lithium-pilocarpine model of temporal lobe epilepsy 总被引:10,自引:0,他引:10
Voutsinos-Porche B Koning E Kaplan H Ferrandon A Guenounou M Nehlig A Motte J 《Neurobiology of disease》2004,17(3):385-402
To better understand the role of inflammatory responses in temporal lobe epilepsy, we characterized Interleukin1-beta (IL1-beta), Nuclear Factor-kappaB (NF-kappaB), and Cyclooxygenase-2 (COX-2) expression together with neurodegeneration in the rat lithium-pilocarpine model. The immunohistochemical expression of IL1-beta, NF-kappaB, and COX-2 started by 12 h post-injection, persisted for 24 h (status epilepticus period), and returned to basal levels by 3 and 6 days (latent period). The regional distribution of IL1-beta, NF-kappaB, and COX-2 occurred mainly in structures prone to develop neuronal damage. Using double-staining protocols, we detected IL1-beta expression in glial cells, COX-2 expression in neurons, and NF-kappaB in both cell types. The presence of Fluoro-Jade-B-positive degenerating neurons was associated with IL1-beta, NF-kappaB, and COX-2 proteins expression during status epilepticus but not during the latent period while neurons were still degenerating. These data suggest that seizure-related IL1-beta, NF-kappaB, and COX-2 expression may contribute to the pathophysiology of epilepsy by inducing neuronal death and astrocytic activation. 相似文献
99.
Early functional recovery and the fate of the diffusion/perfusion mismatch in patients with proximal middle cerebral artery occlusion 总被引:2,自引:0,他引:2
Singer OC Du Mesnil De Rochemont R Foerch C Stengel A Sitzer M Lanfermann H Neumann-Haefelin T 《Cerebrovascular diseases (Basel, Switzerland)》2004,17(1):13-20
BACKGROUND: The relationship between early neurological recovery, time to recanalization and the salvage of hypoperfused, but not diffusion-restricted tissue was investigated. METHODS: In 17 patients with acute middle cerebral artery occlusion, a multiparametric stroke MRI protocol was performed < 6 h after symptom onset, as well as at day 2 and 7. Recanalization was monitored with transcranial Doppler or with conventional angiography (during local thrombolysis). Functional improvement was defined as a change of > or = 4 points on the National Institutes of Health Stroke Scale score. RESULTS: In patients with functional improvement, 78% (median, range 66-95%) of the acute mean transit time (MTT) lesion escaped infarction compared with 28% (median, range -13 to 78%) in patients without neurological improvement (p < 0.01). Similarly, the percentage of tissue with a time-to-peak (TTP) delay of > or = 2 s not progressing to infarction was 80 and 4% in the groups with and without improvement, respectively (p < 0.01). Neurological improvement was more frequent in patients with early (< or = 3 h after presentation) recanalization, due to the salvage of larger areas of initially hypoperfused tissue. CONCLUSIONS: The salvage of hypoperfused tissue is a major factor influencing early neurological improvement. 相似文献
100.
Sjolie AN 《Scandinavian journal of medicine & science in sports》2004,14(3):168-175
The objective of this cross-sectional study was to investigate whether body mass index (BMI) and hip mobility are associated with low-back pain (LBP) in adolescents. The study population included all adolescents in 8th and 9th grades in a rural and in an urban area in Eastern Norway. Eighty-eight adolescents participated (mean age 14.7 years), making the response rate 84%. LBP was assessed by a questionnaire answered in the classrooms as pain/discomfort in the low back during the preceding year. Body height and weight were measured, and BMI was calculated. Hip mobility was measured as active movements by a goniometer. The level of significance was set to P< or =0.05. In bivariate analysis for the whole group, LBP was associated positively with a higher than mean BMI, while LBP among boys was associated with a less than mean hip flexion, internal rotation, and hamstrings flexibility. In multiple regression analyses, adjusting for gender and well-being, LBP was associated with a higher than mean BMI, a less than mean hamstrings flexibility, and a less than mean hip flexion. The results suggest further prospective research to investigate whether poor hip mobility and high BMI may predict juvenile LBP. 相似文献