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61.
Bush DA Dunbar RD Bonnet R Slater JD Cheek GA Slater JM 《AJR. American journal of roentgenology》1999,172(3):735-739
OBJECTIVE: Although radiation therapy is used in early-stage inoperable lung cancer, it often results in injury to functional lung tissue. A study was undertaken to determine the frequency and severity of pulmonary injury revealed by CT in patients who had undergone conformal proton (to a limited volume) radiation therapy. We compared these findings with those from a group of patients who had undergone a combination of photon and conformal proton (to a larger volume) radiation therapy. CONCLUSION: Proton radiation therapy was associated with a lower frequency of pulmonary injury than the combined regimen. Injury correlated well with the volume of normal lung that was irradiated. Conformal proton radiation therapy appears to be able to reduce the incidence and severity of pulmonary injury revealed by CT. 相似文献
62.
Donaldson GW Moinpour CM Bush NE Chapko M Jocom J Siadak M Nielsen-Stoeck M Bradshaw JM Bichindaritz I Sullivan KM 《Evaluation & the health professions》1999,22(4):427-441
The authors randomly selected 400 physicians from a population of 1,545 practicing physicians providing follow-up care to patients who received bone marrow or blood stem cell transplants at the Fred Hutchinson Cancer Research Center to determine interest in receiving Internet-based transplant information. In a two-factor completely randomized factorial design, the 400 physicians were assigned to receive mailed surveys with either no compensation or a $5 check and either no follow-up call or a follow-up call 3 weeks after mailing. Overall, 51.5% of the physicians returned the mailed surveys. Comparison of logit models showed that inclusion of a $5 check in the mailer significantly (p = .016) increased the probability of returning the surveys (57.5% vs. 45.5%). In contrast, the telephone follow-up had no overall effect. The authors concluded a modest financial reward can significantly improve physician response rates to research surveys but a telephone follow-up may be inefficient and even ineffective. 相似文献
63.
Rationale: The mesolimbic dopamine (DA) system is implicated in psychostimulant drug self-administration. The neuropeptide cholecystokinin
(CCK) is co-localised with DA and inhibits nucleus accumbens (NAcc) DAergic neurotransmission via CCKB receptors. Objectives: The present experiment was designed to examine the effects of intra-NAcc CCKB receptor stimulation on fixed-ratio (FR) amphetamine self-administration. Methods: Wistar rats with intravenous catheters and NAcc cannulae were trained to self-administer amphetamine under a FR3 schedule
of reinforcement. Animals performing stable self-administration were microinjected with pentagastrin and assessed during 3-h
sessions. Results: Intra-NAcc pentagastrin dose dependently increased amphetamine intake. Conclusions: These results are consistent with the notion that NAcc CCKB receptor activation attenuates amphetamine reward.
Received: 6 May 1999 / Final version: 4 August 1999 相似文献
64.
A model is presented which links up recent findings regarding the biochemical substrates of neurological networks mediating pleasure states with the concept of animal behavior relating to bonding. The forms of human bonding (parent-child, kinship, friendship) have analogies in the animal world and appear to be based on a combination of fixed action patterns, learning behaviors supported by endogenous secretion of "pleasure-producing" endorphines, and social reinforcement. The implications of this model for psychiatric treatment and rehabilitation are discussed. 相似文献
65.
In an attempt to evaluate the degree of in vitro cellular sensitization to tumor and its relationship to clinical responsiveness, direct leukocyte migration tests were carried out in patients with varying degrees of adenocarcinoma of the prostate employing pooled allogeneic extracts of normal, benign, and malignant prostatic tissue as a source of antigen. Cell-mediated immunity to presumably common prostatic tumor associated antigens was observed. The degree of sensitization of clinically significant specific reactivity of the patients' leukocytes to malignant prostatic tissue was greatest in patients with localized disease, low-grade tumor, and clinically inactive disease than in patients with advanced disease, high-grade tumor, and clinically active disease. Evaluation of the possible correlation of specific reactivity to malignant prostatic tissue as a prognostic index of clinical responsiveness revealed a positive correlation with the degree of sensitization in 3 (43 per cent) of 7 patients. Correlation in 4 patients was questionable because of observations of "stimulation" of migration rather than inhibition, suggested by some to be reflective of weak sensitization to tumor. Evaluation of a larger patient population as well as a prospective study of the relationship of the degree of sensitization and clinical responsiveness will be necessary before any definitive conclusions may be drawn regarding the present observations. 相似文献
66.
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68.
Polly A Newcomb Angela C Bush Gerald L Stoner Johanna W Lampe John D Potter Jeannette Bigler 《Cancer epidemiology, biomarkers & prevention》2004,13(4):662-666
JC virus (JCV) is an ubiquitous human polyomavirus that frequently resides in the kidneys of healthy individuals and is excreted in the urine of a large proportion of the adult population. Polyomaviruses are associated with disease largely in immunocompromised individuals (progressive multifocal leukoencephalopathy). Colorectal cancers can show chromosome instability and it was hypothesized that JCV may account for some of this instability. We screened urine from 45 healthy donors and 233 colorectal cancer/normal tissue pairs for the presence of JCV sequences using a Taqman assay. This assay could detect 1 virus genome in 10 human genomes. In the urine samples, we found an infection rate of approximately 70%. The JCV isolates in these samples could be categorized into four JCV types (2B, 4, 7, and 8), none of which had a rearranged regulatory region. Among the colon tissues, one normal tissue (<0.5%) and none of the matched tumors tested positive for JCV. There is no evidence in these data to indicate that JCV is the cause of genetic instability in colorectal cancer. 相似文献
69.
FJ Cowan JT Warner LM Lowes JP Riberio JW Gregory 《Archives of disease in childhood》1997,77(2):109-114
AIMS: To define outcome measures for auditing the clinical care of children and adolescents with insulin dependent diabetes mellitus (IDDM) and to assess the benefit of appointing a dedicated paediatric trained diabetes specialist nurse (PDSN). METHODS: Retrospective analysis of medical notes and hospital records. Glycaemic control, growth, weight gain, microvascular complications, school absence, and the proportion of children undergoing an annual clinical review and diabetes education session were assessed. The effect of the appointment of a PDSN on the frequency of hospital admission, length of inpatient stay, and outpatient attendance was evaluated. RESULTS: Children with IDDM were of normal height and grew well for three years after diagnosis, but grew suboptimally thereafter. Weight gain was above average every year after diagnosis. Glycaemic control was poor at all ages with only 16% of children having an acceptable glycated haemoglobin. Eighty five per cent of patients underwent a formal annual clinical review, of whom 16% had background retinopathy and 20% microalbuminuria in one or more samples. After appointing the PDSN the median length of hospital stay for newly diagnosed patients decreased from five days to one day, with 10 of 24 children not admitted. None of the latter was admitted during the next year. There was no evidence of the PDSN affecting the frequency of readmission or length of stay of children with established IDDM. Non-attendance at the outpatient clinic was reduced from a median of 19 to 10%. CONCLUSIONS: Outcome measures for evaluating the care of children with IDDM can be defined and evaluated. Specialist nursing support markedly reduces the length of hospital stay of newly diagnosed patients without sacrificing the quality of care. 相似文献
70.
FJ Cowan JT Warner FD Dunstan WD Evans JW Gregory HR Jenkins 《Archives of disease in childhood》1997,76(4):325-329
The prevalence of osteopenia in children with inflammatory bowel disease (IBD) is unknown. The effect of nutritional state, disease activity, and steroid therapy on bone mineral content (BMC) of whole body, lumbar spine, and left femoral neck measured by dual energy x ray absorptiometry in 32 children with IBD was assessed by comparison with 58 healthy local school children. Using the control data, a predicted BMC was calculated taking into account bone area, age, height, weight, and pubertal stage. The measured BMC in children with IBD was expressed as a percentage of this predicted value (% BMC). Mean (SD) % BMC was significantly reduced for the whole body and left femoral neck in the children with IBD (97.0 (4.5)% and 93.1 (12.0)% respectively, p < 0.05). Of the children with IBD, 41% had a % BMC less than 1 SD below the mean for the whole body and 47% at the femoral neck. Reduction in % BMC was associated with steroid usage but not with the magnitude of steroid dose, disease activity, or biochemical markers of bone metabolism. In conclusion, osteopenia is relatively common in childhood IBD and may be partly related to the previous use of steroids. 相似文献