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71.
Chemokines are a diverse group of small proteins that effect cell signaling by binding to G-protein-coupled, seven-trans-membrane receptors. Our group had found previously that the chemokine receptor CCR1 was present in neurons and dystrophic processes in a small sample of Alzheimer's disease cases. This expanded immunohistochemical study shows that the number of CCR1-positive plaque-like structures in the hippocampus and entorhinal cortex is highly correlated to dementia state as measured by the clinical dementia rating score. CCR1 immunoreactivity is found in dystrophic, neurofilament-positive, synaptophysin-negative neurites that are associated with senile plaques containing amyloid beta peptides of the 1-42 species (Abeta42). CCR1 was not, however, associated with diffuse deposits of Abeta42. There was limited expression of CCR1 in neurofibrillary tangle-bearing neuritic processes. Astrocytes and microglia were typically negative for CCR1. Human brains from age-matched, nondemented individuals rarely displayed either CCR1 or Abeta42 immunoreactivity. Seven other types of dementing neurodegenerative diseases were examined, and all failed to demonstrate CCR1 immunopositivity unless Abeta42-positive plaques were also present. Thus, neuronal CCR1 is not a generalized marker of neurodegeneration. Rather, it appears to be part of the neuroimmune response to Abeta42-positive neuritic plaques.  相似文献   
72.
Deep brain stimulation (DBS) of the subthalamic nucleus (STN) has become an effective strategy in the treatment of motor symptoms in advanced Parkinson's disease. However, clinical studies have shown that DBS can affect verbal fluency. Seven Parkinson's disease patients with bilateral DBS of the STN were studied with positron emission tomography (PET) to investigate the effects of STN stimulation on regional cerebral blood flow during a verbal fluency task. Activation of the right orbitofrontal cortex and verbal fluency-associated activation within a left-sided frontotemporal network were decreased during STN stimulation compared with the OFF state. Our results offer an explanation for the commonest neuropsychological side effect of STN stimulation and show that STN stimulation affects a frontotemporal network during a fluency task.  相似文献   
73.
To assess temporal brain deficits consecutive to severe birth hypoxia, newborn rats were exposed for 20 min to 100% N2. This treatment induced a long-term growth retardation and a delayed, but only transient, neuronal loss (approximately 25%) in the CA1 hippocampus and parietal cortex, starting from 3 days and peaking at 6 days post-hypoxia. The expression profiles of various apoptosis-regulating proteins (including Bcl-2, Bax, p53 and caspase-3) were well correlated to the alterations of nuclear morphology depicted by 4,6-diamidino-2-phenylindole (DAPI). Whereas they confirmed a gradual histological recovery, specific DNA fragmentation patterns suggested that birth hypoxia may transiently reactivate the developmental programme of neuronal elimination. Although they successfully achieved various behavioral tests such as the righting reflex, negative geotaxis, locomotor coordination, and the eight-arm maze tasks, both developing and adult hypoxic rats were repeatedly slower than controls, suggesting that birth hypoxia is associated to moderate but persistent impairments of functional capacities.  相似文献   
74.
Ectopic cervical thymic tissue is an uncommon cause of neck masses in children, with fewer than 100 cases reported in children who presented with primary neck masses. To illustrate the unique characteristics of these tumors, we report the case of a 13-month-old boy with ectopic thymic tissue presenting with asymptomatic, bilateral, and solid cervical masses. This case report highlights several unique findings: (1) the rare nature of solid thymic tumors compared with cystic lesions, (2) the utility of magnetic resonance imaging scanning with and without fat suppression for diagnosis, and (3) the risks of surgical removal of thymic tissue in children. Despite its infrequent occurrence and often asymptomatic presentation, ectopic cervical thymus masses should be included as a rare cause of cervical masses in the pediatric population. Awareness of this diagnosis will allow for appropriate preoperative diagnostic studies, which may preclude the need for biopsy.  相似文献   
75.
76.
Perioperative managers: role stressors and strategies for coping   总被引:1,自引:0,他引:1  
This qualitative study explored the role stressors experienced by perioperative nurse managers, and identified resources and strategies they used in order to cope with the multiple demands upon their role. Grounded Theory methodology was used to inform the inquiry through interviews with the participants and thematic analysis of the data. The perioperative nurse managers who participated in the study indicated that the major stressors they experienced were related to managing their staff Stress was reduced through the use of hospital resources and peer support, referring to post management education and information obtainedfrom attending conferences. In addition, they used team building strategies, balanced priorities and engaged in social activities. These findings will assist directors of nursing and other nursing leaders in formulating the direction of appropriate support and structure for the development of perioperative nurse managers.  相似文献   
77.
Zusammenfassung Hintergrund: Zur Analyse von H?ufigkeit und Risikofaktoren der bronchopulmonalen Dysplasie (BPD) auf dem Hintergrund der sich ?ndernden Bedingungen der perinatalen Medizin untersuchten wir retrospektiv die Verl?ufe Frühgeborener, die in der Zeit von Januar 1985–Dezember 1992 an unserer Klinik betreut wurden. Material und Methoden: W?hrend des 1. Lebenstags beatmungsbedürftige Frühgeborene eines Geburtsgewichts von < 1751 g wurden in die retrospektive Studie einbezogen. Die BPD wurde definiert als Beatmungsnotwendigkeit bzw. Sauerstoffbedarf von > 30 % am 28. Lebenstag. Kinder mit BPD wurden mit einer Kontrollgruppe (Geburtsgewicht < 1751 g) verglichen, wobei die Auswahl nach Geburtsjahrg?ngen und Geburtsgewicht erfolgte. Die Risikofaktoren wurden mittels logistischer Regressionsanalyse berechnet. Ergebnisse: Von insgesamt 274 Kindern wurde bei 76 (28 %) eine BPD diagnostiziert, 150 überlebten ohne BPD, w?hrend 48 Kinder verstarben. Risikofaktoren für die BPD stellten bei einer signifikant steigenden überlebensrate und sinkenden BPD-Inzidenz in der logistischen Regressionsanalyse ein niedriges Gestationsalter sowie Geburtsgewicht, vaginale Geburt, hoher Sauerstoffbedarf, geringe Gewichtsabnahme w?hrend der 1. Lebenswoche und fehlende Surfactanttherapie dar. Schlu?folgerung: Wir fanden eine verbesserte überlebensrate beatmungsbedürftiger Frühgeborener bei Reduktion der BPD-H?ufigkeit im Untersuchungszeitraum. Die Kenntnis der BPD-Risikofaktoren sollte in pr?ventive Konzepte umgesetzt werden.   相似文献   
78.
Postoperative vomiting (POV) after strabismus surgery in children results in discomfort and prolonged hospital stays. Opioids increase the incidence of POV. Remifentanil has a context-sensitive half-life of 3 to 4 min, and how this short half-life influences POV in those patients is unknown. We conducted a prospective, double-blinded study in 81 ASA status I or II children from 2 to 12 yr of age undergoing elective strabismus surgery under general anesthesia. Patients were randomized to receive either remifentanil (bolus 1 microg/kg; infusion 0.1-0.2 microg x kg(-1) x min(-1)) or fentanyl (2 microg/kg, and 1 microg/kg every 45 min). POV episodes were recorded for 25 h. Pain scores were obtained by using an objective pain scale for 60 min during recovery. The number of patients who experienced POV did not differ significantly between groups (49% vs 48%). However, in the Remifentanil group, POV episodes were significantly less frequent (0.95 vs 2.2 episodes). In contrast, fentanyl was associated with lower pain scores during the first 30 min of recovery. We conclude that children undergoing strabismus surgery under balanced anesthesia with remifentanil, compared with fentanyl, showed less frequent POV. However, early postoperative analgesia was better with fentanyl. IMPLICATIONS: Opioids increase the incidence of postoperative vomiting (POV). Remifentanil is characterized by the shortest half-life of all opioids used in anesthetic practice. Therefore, we studied the effect of remifentanil on POV compared with the longer-acting opioid fentanyl in children undergoing strabismus surgery.  相似文献   
79.
Consumer satisfaction and social validity were measured during a double-blind, placebo-controlled evaluation of the atypical neuroleptic risperidone in treating severe aberrant behavior of persons with developmental disabilities. First, a satisfaction survey was completed after a medication trial by each participant's caregiver. Results showed that 100% of the caregivers felt that participation was a positive experience for themselves and participants. Second, 52 community members viewed videotapes of 5 participants during a clinical interview when they were taking either placebo or risperidone. Raters also indicated that when on the medication, participants displayed fewer aberrant behaviors, were less irritable, in a better mood, and were more responsive to their environment.  相似文献   
80.
Integration of information from multiple senses is fundamental to perception and cognition, but when and where this is accomplished in the brain is not well understood. This study examined the timing and topography of cortical auditory-visual interactions using high-density event-related potentials (ERPs) during a simple reaction-time (RT) task. Visual and auditory stimuli were presented alone and simultaneously. ERPs elicited by the auditory and visual stimuli when presented alone were summed ('sum' ERP) and compared to the ERP elicited when they were presented simultaneously ('simultaneous' ERP). Divergence between the 'simultaneous' and 'sum' ERP indicated auditory-visual (AV) neural response interactions. There was a surprisingly early right parieto-occipital AV interaction, consistent with the finding of an earlier study [J. Cogn. Neurosci. 11 (1999) 473]. The timing of onset of this effect (46 ms) was essentially simultaneous with the onset of visual cortical processing, as indexed by the onset of the visual C1 component, which is thought to represent the earliest cortical visual evoked potential. The coincident timing of the early AV interaction and C1 strongly suggests that AV interactions can affect early visual sensory processing. Additional AV interactions were found within the time course of sensory processing (up to 200 ms post stimulus onset). In total, this system of AV effects over the scalp was suggestive of both activity unique to multisensory processing, and the modulation of 'unisensory' activity. RTs to the stimuli when presented simultaneously were significantly faster than when they were presented alone. This RT facilitation could not be accounted for by probability summation, as evidenced by violation of the 'race' model, providing compelling evidence that auditory-visual neural interactions give rise to this RT effect.  相似文献   
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