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941.
Effect of Scutellariae radix extract on the high glucose-induced apoptosis in cultured vascular endothelial cells 总被引:1,自引:0,他引:1
Suh KS Nam YH Ahn YM Kim NJ Park CY Koh G Oh S Woo JT Kim SW Kim JW Kim YS 《Biological & pharmaceutical bulletin》2003,26(11):1629-1632
Endothelial cell apoptosis has been postulated as the initial trigger of the progression of microvascular disease in patients with diabetes mellitus. To investigate the role of Scutellariae radix extract, we examined its effect on the endothelial cell proliferation using the [3H]-thymidine incorporation method. Scutellariae radix extract significantly stimulated endothelial cell proliferation in a dose-dependent manner. We focused on the protective action of Scutellariae radix extract on the endothelial cell apoptosis induced by high glucose concentrations. Determination of endothelial cell apoptosis was performed using DNA gel electrophoresis, terminal deoxynuclotidyl transferase-mediated dUTP nick end-labeling (TUNEL) assay, and an ELISA kit. Exposure of vascular endothelial cell to high glucose (16.7 mM) for 72 h resulted in a significant increase in apoptosis, compared with the normal glucose concentrations (5.5 mM). Scutellariae radix extract inhibited high glucose-induced endothelial cell apoptosis. This result suggests that Scutellariae radix extract may contribute to antiapoptotic action against vascular endothelial cells, resulting in a beneficial effect in preventing diabetes-associated microvascular complications. 相似文献
942.
Patricia A. Hebda PhD ; Diana Whaley BS ; Hyung-Gyoon Kim PhD ; Alan Wells MD DSc 《Wound repair and regeneration》2003,11(5):373-379
Temporally controlled expression of genes in transgenic mice has advanced our understanding of many physiological processes. One of the more common modes of acutely altering gene levels involves the doxycycline-regulated "tet-on/tet-off" systems. There has been concern that the administration of doxycycline in itself might compromise many aspects of wound repair. Here we report that oral ad libitum administration of doxycycline (2 mg/ml in drinking water) to mice does not alter dermal or epidermal wound healing. The healing of both full- and partial-thickness skin wounds proceeded similarly regardless of doxycycline administration; in fact, collagen organization and tensile strength development appeared to accelerate in the presence of doxycycline. These data suggest that wound healing studies incorporating transgene expression can utilize tet-on/tet-off regulation of gene expression without interference from doxycycline. 相似文献
943.
STUDY DESIGN: In this cadaveric study, a computer-assisted image guidance system was tested for accuracy of thoracic pedicle screw placement. OBJECTIVES: Evaluate the system's accuracy for thoracic pedicle screw placement in vitro. SUMMARY OF BACKGROUND DATA: The effective use and reliability of pedicle screw instrumentation in providing short-segment stabilization and correction of deformity is well known in the lumbar spine. Pedicle screw placement in the thoracic spine is difficult because of the small dimensions of the thoracic pedicles and risk to the adjacent spinal cord and neurovascular structures. Investigators have shown the improved accuracy of computer-assisted lumbar pedicle screw placement; but the accuracy of computer-assisted thoracic pedicle screw placement, which is becoming more widely used, has not been shown. METHODS: In five human cadavers, 120 thoracic pedicle screws were placed with computer-assisted image guidance. The largest clinically feasible screw was used based on the cross-sectional dimensions of each pedicle. The accuracy was assessed by postoperative computed tomography and visual inspection. RESULTS: The overall pedicle cortex violation was 23 of 120 pedicles (19.2%). Nine violations (7.5%) were graded as major and 14 (11.7%) as minor. A marked and progressive learning curve was evident with the perforation rates that decreased from 37.5% in the first cadaver to 4.2% in the last two cadavers. CONCLUSIONS: Accurate thoracic pedicle screw placement is feasible with computer-assisted surgery. However, as with any other new surgical technology, the learning curve must be recognized and incorporated into the necessary fundamental knowledge and experience for these procedures. 相似文献
944.
Susan L. Greenspan MD Eric von Stetten PhD Sarah K. Emond BA Lisa Jones BS CNMT Robert A. Parker SCD 《Journal of clinical densitometry》2001,4(4):373-380
The presence of a vertebral fracture significantly increases the risk of future fracture, classifies a patient with "clinical" osteoporosis, and usually results in treatment for osteoporosis. However, the majority of vertebral fractures are silent, and lateral X-rays (the standard method for identification) are not routinely obtained. Instant vertebral assessment (IVA), a technology that utilizes dual X-ray absorptiometry (DXA), provides rapid assessment of vertebral fractures and is highly correlated with vertebral fractures, as assessed on standard lateral spine X-rays. To assess the role of IVA in patient management, we examined standard bone mineral density (BMD) of the spine, total hip, and femoral neck and spine IVA by DXA in 482 participants screened for an osteoporosis study, who had no previous knowledge of vertebral fractures. Using World Health Organization (WHO) guidelines, subjects were classified using BMD at the spine, total hip, femoral neck, or any combination of these central sites. In addition, we considered subjects as osteoporotic if they had vertebral fractures independent of low bone density. We found that vertebral fractures assessed by IVA were present in 18.3% of asymptomatic postmenopausal women recruited for this study. The sensitivity of BMD alone to diagnose osteoporosis based on either a vertebral fracture or low BMD using WHO criteria ranged from 40 to 74%. This means that between 26 and 60% of osteoporotic individuals could have potentially been missed. Furthermore, 11.0-18.7% of clinically osteoporotic individuals would have been classified as normal by BMD criteria alone. We conclude that IVA is a useful adjunct in the clinical identification of osteoporosis and may prevent mismanagement of osteoporotic patients. 相似文献
945.
Jeremy B. White MD Mathieu Barraja MS Tewodros Mengesha MS Sumit Bose BS Samaneh Ashktorab BA Ryan Bahn BS Ryan Vallance PhD William H. Lindsey MD FACS 《The Laryngoscope》2008,118(12):2107-2110
Background: Manipulation and suspension of the superficial musculoaponeurotic system (SMAS) is performed by 74% of rhytidectomy surgeons. Multiple variations in suture techniques are employed in this task, but they have never been evaluated for differences in their ability to withstand stress. Objective: To compare the biomechanical properties of two different suture techniques that are used in SMAS plications during rhytidectomy: a double‐layered running locking (DRL) stitch and multiple horizontal mattress stitches. Methods: Fourteen horizontal mattress plications, in rows of six sutures, and comparable lengths of 16 DRL stitch plications of pig skin samples, were stressed using a tensometer with grip displacement increasing at a constant rate of 0.5 cm/Min. The required force to cause plication failure was recorded for each sample at three suture break points. Results: There was no significant difference between the two groups in the force required to cause the initial suture failure. Unlike the horizontal mattress plication, an initial break seemed to cause minimal to no distortion of the DRL tissue plication. When results were normalized by the initial break forces to account for small variations in tissue properties, the force ratio required to cause a second suture break was significantly larger in the DRL group than in the horizontal mattress technique. This is evidenced by the average second to first break force ratios of 1.62 vs. 1.13 for the DRL and horizontal mattress stitches, respectively, with a P‐value of .60. The mean ratios of third to first break forces for the DRL and horizontal mattress groups were 2.08 and 0.91, respectively, with a P‐value of .08. Conclusion: The DRL stitch requires more force than the horizontal mattress stitch to cause significant failure of tissue plication. This technique may enable plastic surgeons to avoid early revision rhytidectomy due to suture failure, and to create a long‐lasting, youthful cosmetic result. 相似文献
946.
Mapping FACT-P and EORTC QLQ-C30 to Patient Health Status Measured by EQ-5D in Metastatic Hormone-Refractory Prostate Cancer Patients 总被引:2,自引:0,他引:2
Eric Q. Wu PhD Parvez Mulani MS CPhil Max H. Farrell BS Darryl Sleep MD MBBCh FCS 《Value in health》2007,10(5):408-414
OBJECTIVES: To construct and validate a prediction model of preference-adjusted health status (EQ-5D) for metastatic hormone-refractory prostate cancer (HRPCA) patients using cancer-specific health-related quality of life (HRQoL) measures. METHODS: Data were obtained from a multicenter, multinational observational study of metastatic HRPCA patients conducted during 2002 to 2004. In addition to clinical and resource utilization, preference-adjusted health status (EQ-5D) and HRQoL (Functional Assessment of Cancer Therapy-Prostate [FACT-P] and European Organization for Research and Treatment of Cancer Quality of Life Questionnaire [EORTC QLQ-C30]) data were collected. Predictive validity of ordinary least square (OLS) and median regressions of various model specifications were tested using cross-validation samples. The selected specification was then further refined and tested for alternative model specifications and restrictions. RESULTS: OLS regression with both HRQoL measures as individual components and patient demographics was the best-performing model. It explained 58.2% of the observed EQ-5D variation in the validation sample. A model including only the prostate cancer-specific HRQoL measure, FACT-P, explained 53.5% of the observed EQ-5D variation. CONCLUSIONS: The models developed have good predictive validity. These algorithms enable researchers to translate cancer-specific HRQoL measures to preference-adjusted health status in metastatic HRPCA patients. The findings will help perform health status adjustments in cost-utility analyses. 相似文献
947.
The term leishmaniasis refers to the spectrum of disease caused by Leishmania species. The clinical manifestations of leishmaniasis depend on complex interactions between the virulence characteristics
of the infecting Leishmania species and the genetically determined cell-mediated immune responses of its mammalian host. Leishmaniasis comprises three
major syndromes: cutaneous, mucosal, and visceral. Variations exist within each syndrome. 相似文献
948.
MONICA EMMETT BA HEATHER JEFFERY MB BS MRACP DIANNE CHANDLER SRN ALAN E. DUGDALE MO 《Journal of paediatrics and child health》1980,16(2):90-93
Fourteen children who had had Haemophilus influenzae meningitis more than two years earlier have been compared with their siblings. WISC, Frostig and Bender psychological tests and neurological examination were performed so that subject/sibling differences could be analysed. On neurological examination, subjects overall performed worse than the controls, although no "hard" neurological signs were found. Prolonged fever during the meningitis was associated with poorer results in psychological tests. In the subjects, there was a significant increase in left lateral dominance which may have been due to brain damage by the meningitis. However, most subjects did not differ significantly from their siblings in the tests, suggesting that prompt and adequate treatment of bacterial meningitis can prevent sequelae. 相似文献
949.
R. D. MESSER MB BS FRACP ANNA M. RUSSO B Sc W. R. McWHIRTER BA MB Ch B FRCP FRACP DAWN SPRANGEMEYER B Sc MB BS JUNE W. HALLIDAY B Sc Ph D. 《Journal of paediatrics and child health》1980,16(3):185-188
Serum ferritin levels were examined in maternal serum, In cord sera and at one, four, eight and twelve weeks in 19 term and 28 preterm infants. There was no correlation between maternal and cord ferritin levels. Mean serum ferritin concentration was lower in preterm infants, and both term and preterm Infants exhibited' an initial rise in serum ferritin concentration followed by a steady fall. Serum ferritin concentration showed a good correlation with calculated iron stores at twelve weeks of age suggesting that serum ferritin estimation is the method of choice for monitoring body iron stores in infants. No correlation was found between serum ferritin concentration and calculated iron intake at any age in either term or preterm infants. It is suggested that iron supplementation additional to that present in modified cow's milk is not necessary for the first twelve weeks of life in either term or preterm infants. 相似文献
950.
DONALD L. BUTLER MB. BS MERLE de SILVA DMRD RCP & S MRACR 《Journal of paediatrics and child health》1980,16(4):279-283
Intracranial haemorrhage was found in 22 infants with the aid of computerised tomography (CT). Six (27%) of these infants were full-term. Seven infants died (32%). Most infants displayed clinical features normally associated with intracranial haemorrhage (ICH), but In two Infants fever was the most striking presenting sign of the haemorrhage. Lumbar puncture was only helpful in diagnosing intraventricular haemorrhage.
Three types of haemorrhages were seen on the scans: intracerebral, subdivided Into subependymal, intracerebral and cortical; intraventricular; and midline interhemispheric. The latter haemorrhage was shown at autopsy to be located within the falx. This type of haemorrhage was seen in 19 of the 22 cases, both as an isolated haemorrhage and more usually, in combination with the other types. 相似文献
Three types of haemorrhages were seen on the scans: intracerebral, subdivided Into subependymal, intracerebral and cortical; intraventricular; and midline interhemispheric. The latter haemorrhage was shown at autopsy to be located within the falx. This type of haemorrhage was seen in 19 of the 22 cases, both as an isolated haemorrhage and more usually, in combination with the other types. 相似文献