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21.
A study of C4 bound to human erythrocytes in vitro and in vivo has been made by immunoblotting with mouse monoclonal anti-C4c and anti-C4d and human polyclonal anti-C4d (Rodgers and Chido) following SDS-PAGE. Multi-banded patterns differentiated between C4A and C4B isotypes. Treatment of EC4b with trypsin eliminated immunoblotting but not agglutination reactions. Serum inactivation (factor I) of EC4b resulted in banding patterns similar to those obtained from patients' EC4d. Treatment of EC4b membranes with NH2OH affected many of the bands, two were lost, one was markedly reduced and others had altered SDS-PAGE mobility. Interpretation of the bands has been made in terms of C4-acceptor complexes and inactivation fragments of C4. A distinct difference in the banding of C4A and C4B isotypes has been detected. 相似文献
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Marlene Duarte Giles Andrea L Nelson Felisa Shizgal Eva-Marie Stern Anne Fourt Pat Woods Judith I Langmuir Catherine C Classen 《Journal of trauma & dissociation》2007,8(4):7-24
This article describes the Women Recovering from Abuse Program (WRAP), an outpatient day-hospital program for women suffering from the sequelae of childhood abuse. WRAP was conceived in 1998 by clinicians who advocated for its development based on a growing need to provide women who had experienced childhood trauma an alternative to an inpatient program. WRAP draws from a Stage 1 treatment approach to address chronic interpersonal trauma and dissociation by incorporating psychopharmacology, individual and group psychotherapy. The program is structured into two phases: a preparatory Building Resources Group (BRG) and an intensive multimodal segment comprised of seven types of group therapy. Each group is described in terms of the treatment rationale and its structure and process. Two research studies to date support the effectiveness of WRAP. 相似文献
24.
Folic acid and vitamin B12 levels in pregnancy and their relation to megaloblastic anaemia 总被引:1,自引:6,他引:1
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There is a significant fall in the serum folic acid level during pregnancy, reaching its lowest level at term. This is most pronounced in twin pregnancies. A similar but less spectacular fall occurs in the vitamin B12 concentration. 相似文献
25.
Neuroimaging of NREM sleep in primary insomnia: a Tc-99-HMPAO single photon emission computed tomography study 总被引:5,自引:0,他引:5
STUDY OBJECTIVES: The objectives of this study were to: 1) demonstrate the feasibility of combining polysomnography and SPECT neuroimaging to study NREM sleep in primary insomnia and 2) evaluate possible functional CNS abnormalities associated with insomnia. DESIGN: Patients with insomnia and good sleeper controls were studied polysomnographically for three nights with a whole brain SPECT Scan of NREM sleep on Night 3. Groups were screened for medical/psychiatric history, substance use, and matched on age, body mass index, and education. SETTING: Sleep Research Laboratory and Nuclear Medicine Center PARTICIPANTS: Nine females, 5 patients with chronic psychophysiologic insomnia and 4 healthy good sleepers (mean age 36 years, SD 12, range 27-55). INTERVENTIONS: N/A MEASUREMENTS AND RESULTS: Tomographs of regional cerebral blood flow during the 1st NREM sleep cycle were successfully obtained. Contrary to our expectations, patients with insomnia showed a consistent pattern of hypoperfusion across all 8 pre-selected regions of interest, with particular deactivation in the basal ganglia (p=.006). The frontal medial, occipital, and parietal cortices also showed significant decreases in blood flow compared to good sleepers (p<.05). Subjects with insomnia had decreased activity in the basal ganglia relative to the frontal lateral cortex, frontal medial cortex, thalamus, occipital and parietal cortices (p<.05). CONCLUSIONS: This study demonstrated the feasibility of combining neuroimaging and polysomnography to study cerebral activity in chronic insomnia. These preliminary results suggest that primary insomnia may be associated with abnormal central nervous system activity during NREM sleep that is particularly linked to basal ganglia dysfunction. 相似文献
26.
In vitro degradation of silk fibroin 总被引:14,自引:0,他引:14
Horan RL Antle K Collette AL Wang Y Huang J Moreau JE Volloch V Kaplan DL Altman GH 《Biomaterials》2005,26(17):3385-3393
A significant need exists for long-term degradable biomaterials which can slowly and predictably transfer a load-bearing burden to developing biological tissue. In this study Bombyx mori silk fibroin yarns were incubated in 1mg/ml Protease XIV at 37 degrees C to create an in vitro model system of proteolytic degradation. Samples were harvested at designated time points up to 12 weeks and (1) prepared for scanning electron microscopy (SEM), (2) lyophilized and weighed, (3) mechanical properties determined using a servohydraulic Instron 8511, (4) dissolved and run on a SDS-PAGE gel, and (5) characterized with Fourier transform infrared spectroscopy. Control samples were incubated in phosphate-buffered saline. Fibroin was shown to proteolytically degrade with predictable rates of change in fibroin diameter, failure strength, cycles to failure, and mass. SEM indicated increasing fragmentation of individual fibroin filaments from protease-digested samples with time of exposure to the enzyme; particulate debris was present within 7 days of incubation. Gel electrophoresis indicated a decreasing amount of the silk 25 kDa light chain and a shift in the molecular weight of the heavy chain with increasing incubation time in protease. Results support that silk is a mechanically robust biomaterial with predictable long-term degradation characteristics. 相似文献
27.
Yeo GS Lank EJ Farooqi IS Keogh J Challis BG O'Rahilly S 《Human molecular genetics》2003,12(5):561-574
Mutations in the melanocortin-4 receptor gene (MC4R) represent the commonest monogenic cause of human obesity. However, information regarding the precise effects of such mutations on receptor function is very limited. We examined the functional properties of 12 different mutations in human MC4R that result in severe, familial, early-onset obesity. Of the nine missense mutants studied, four were completely unable to generate cAMP in response to ligand and five were partially impaired. Four showed evidence of impaired cell surface expression and six of reduced binding affinity for ligand. One mutation in the C-terminal tail, I316S, showed reduced affinity for alpha-MSH but retained normal affinity for the antagonist AgRP. None of the mutations inhibited signaling through co-transfected wild-type receptors. Thus, in the most comprehensive study to date of the functional properties of naturally occurring MC4R mutations we have (1) established that defective expression on the cell surface is a common mechanism impairing receptor function, (2) identified mutations which specifically affect ligand binding affinity thus aiding the definition of receptor structure-function relationships, (3) provided evidence against the notion that these receptor mutants act as dominant-negatives, and (4) identified a potentially novel molecular mechanism of receptor dysfunction whereby a mutation alters the relative affinities of a receptor for its natural agonist versus antagonist. 相似文献
28.
Review of tethered cord syndrome with a radiological and anatomical study: Case report 总被引:1,自引:0,他引:1
LGF Giles 《Surgical and radiologic anatomy : SRA》1991,13(4):339-343
Summary The primary tethered cord syndrome has been documented mainly in children and adolescents but also in adults, and patients may present with backache, neuromuscular skeletal changes such as club-foot, scoliosis, muscular atrophy, disturbances of gait, or dysfunction of bladder and rectum, or a combination of these conditions. The cadaveric case presented describes plain film radiographic and anatomical findings of spina bifida occulta at the first and second sacral levels, and an enlarged spinous process of the fifth lumbar vertebra, in a 78 year old male cadaver with a tethered spinal cord terminating at the first sacral level. During life, this man had not undergone surgery for tethered spinal cord.
Revue du syndrome de moelle attachée: étude radiologique et anatomique à propos d'un cas
Résumé Le syndrome de moelle attachée primaire a souvent été décrit chez l'enfant et l'adolescent mais aussi chez l'adulte, les patients pouvant se présenter avec des douleurs du dos, des modifications neuro-musculaires et squelettiques comme un pied bot, une scoliose, une atrophie musculaire, des anomalies de la marche, des dysfonctionnements de la vessie et/ou du rectum, ou une combinaison de ces différents symptômes. L'observation rapportée ici est l'étude anatomique et radiologique d'un spina bifida oculta des première et deuxième vertèbres sacrées associé à l'élargissement du processus épineux de la cinquième vertèbre lombaire chez un cadavre mâle de 78 ans ayant une moelle épinière attachée au niveau de la première vertèbre sacrée. Durant sa vie ce patient n'avait pas subi de chirurgie pour cette moelle attachée.相似文献
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30.
Neutrophil (PMN) influx is an early, prominent finding in the airways of humans after experimental inhalation of ozone (O3), however the potential for PMN to contribute to epithelial injury in this setting is unknown. Bronchial epithelial cells of the human BEAS 2B R1.4 cell line or primary human bronchial epithelial cells underwent DNA labeling by incubation with BrdU. Monolayers were exposed to O3 (0.05 to 1 ppm) or filtered air for 60 min., and subsequently incubated with PMN for 2 h. Epithelial cell cytolysis was significant only in BEAS exposed to O3 and co-cultured with PMN. Apoptosis was maximal in BEAS exposed to O3 + PMN. Primary bronchial epithelial cells were resistant to injury; no cytolysis was detected, and apoptosis was detected only after treatment with 10 mM H2O2. Neutrophils may increase damage to the respiratory epithelium after O3 exposure, but primary bronchial epithelial cells are resistant to PMN and ozone induced injury. 相似文献