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751.
Improved retroviral transfer of genes into canine hematopoietic progenitor cells kept in long-term marrow culture 总被引:2,自引:0,他引:2
Amphotropic helper-free retroviral vectors containing either the bacterial neomycin phosphotransferase gene (NEO) or a mutant dihydrofolate reductase gene (DHFR*) were used to infect canine hematopoietic progenitor cells. In previous experiments, successful transfer and expression of both genes in canine CFU-GM were achieved after 24-hour cocultivation with virus-producing cells. The average rate of gene expression was 10% (6% to 16%) as measured by the number of CFU-GM resistant to either the aminoglycoside G418 or methotrexate. In an attempt to increase the efficiency of gene transfer, marrow was cocultured for 24 hours with either NEO or DHFR* virus-producing packaging cells and then kept in long-term marrow culture fed three times with virus-containing supernatant (2 to 5 x 10(6) CFU/mL). After six days, cells were harvested and cultured in CFU-GM assay with and without a selective agent. The average rate of gene expression in CFU- GM in five independent experiments was 46% and ranged from 19% to 87%. In conclusion, the efficiency of gene transfer into canine hematopoietic progenitor cells has been increased fourfold by combining cocultivation with long-term marrow culture as compared with results obtained with cocultivation only. 相似文献
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Treatment of femoral fractures in children by pediatric orthopedists: results of a 1998 survey. 总被引:8,自引:0,他引:8
J O Sanders R H Browne J F Mooney E M Raney B D Horn D J Anderson W L Hennrikus W W Robertson 《Journal of pediatric orthopedics》2001,21(4):436-441
SUMMARY: This study aimed to determine treatment preference of various femoral fracture patterns in children by pediatric orthopedists and whether it is practice dependent. In September 1998, members of the Pediatric Orthopedic Society of North America were surveyed to determine their current preferences in treating each of four middle one-third femoral fracture patterns in four age groups. Forty-four percent (286/656) of those surveyed responded. For each fracture pattern, operative treatment was increasingly preferred over nonoperative as patient age increased, and the preferred treatments within the operative and nonoperative categories changed significantly as patient age increased. Fourteen specific cases of femoral head avascular necrosis were noted after rigid reamed and unreamed rodding. There is a statistically significant trend by pediatric orthopedists to treat older children's femur fractures operatively and younger children's nonoperatively. The consensus treatment is age dependent. The numerous cases of avascular necrosis after rigid rodding are a concern. 相似文献
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Pain represents the major motivating factor for which individuals seek healthcare, and pain responses are characterized by substantial inter‐individual differences. Increasing evidence suggests that genetic factors contribute significantly to individual differences in responses to both clinical and experimental pain. The purpose of this review article was to summarize the current literature regarding genetic contributions to pain, highlighting findings relevant to oral pain where available. A brief discussion of methodologic considerations is followed by a review of findings regarding genetic influences on clinical pain. Next, the literature examining genetic contributions to experimental pain responses is presented, emphasizing genetic associations that have been replicated in multiple cohorts. It is hoped that an enhanced understanding of genetic contributions to pain responses will ultimately improve diagnosis and treatment of clinical pain conditions. 相似文献
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ME Bigal RB Lipton DM Biondi J Xiang & J Hulihan 《Cephalalgia : an international journal of headache》2009,29(11):1188-1196
Migraine, particularly migraine with aura, and increased body weight are independent risk factors for cardiovascular disease (CVD). The association of weight change and clinical markers of CVD risk was evaluated in subjects participating in a randomized double-blind, parallel-group study of migraine-preventive treatment comparing 100 mg/day of topiramate and amitriptyline. Individuals from both treatment groups were pooled and stratified into three groups. The 'major weight gain' group gained ≥ 5% of their baseline body weight at the conclusion of the study; the 'major weight loss' group lost ≥ 5% of their baseline body weight. The third group had < 5% of weight change. The influence of weight change in headache outcomes, as well as in markers of CVD (blood pressure, cholesterol, C-reactive protein), was assessed using analysis of covariance. Of 331 subjects, 52 (16%) experienced major weight gain and 56 (17%) experienced major weight loss. Weight change was not associated with differential efficacy for the treatment of headache. However, contrasted with those with major weight loss, those who gained weight experienced elevations in mean diastolic blood pressure (+2.5 vs. −1.2 mmHg), heart rate (+7.6 vs. −1.3 beats per minute), glycosylated haemoglobin (+0.09% vs. −0.04%), total cholesterol (+6.4 vs. −6.3 mg/dl), low-density lipoprotein cholesterol (+7.0 vs. −4.4 mg/dl) and triglycerides (+15.3 vs. −10.4 mg/dl) and an increase in high-sensitivity C-reactive protein (+1.8 vs. −1.9 mg/l). Both groups experienced decreases in systolic blood pressure (−4.0 vs. −1.3 mmHg) and high-density lipoprotein cholesterol (−3.7 vs. −0.8 mg/dl). Increased weight during migraine treatment is not associated with poor headache treatment outcomes, but is associated with deterioration of CVD risk markers. 相似文献
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The article deals with endoscopic endonasal transsphenoidal surgery, which has gained great interest among the modem trends of neurosurgery. Application of extended endoscopic endonasal transsphenoidal approaches significantly advances capabilities of transsphenoidal surgery. Pituitary adenomas and some other sellar tumors which traditionally require transcranial procedure now can be removed via endonasal route. 相似文献