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61.
State-of-the-Art FDG-PET imaging of lung cancer 总被引:3,自引:0,他引:3
The D-glucose analog 2-(fluorine-18)-fluoro-2-deoxy-D-glucose (FDG) is the most commonly used radionuclide in positron emission tomography (PET) of lung cancer. FDG-PET is a molecular imaging technique that images the preferential accumulation of FDG in malignant tissues with increased metabolism. Although FDG-PET is sensitive in the detection of lung cancer, FDG is not tumor specific and may accumulate in a variety of nonmalignant conditions. Occasional false-negative results may also occur. Whole body FDG-PET is a useful noninvasive technique to stage known or suspected non-small-cell lung cancer. The results allow more efficient use of invasive methods for histopathological staging. The combined use of CT and PET in dual imaging increases the number of patients with correctly staged non-small-cell lung cancer. CT/PET is also useful in the assessment of recurrent or residual disease. Future imaging agents are being developed which may allow more selective accumulation of radiopharmaceutical in malignant tissues. 相似文献
62.
Lipotoxicity is closely related to the etiology and complications of type 2 diabetes mellitus. This study investigated the protective effect of an extract from bamboo Phyllostachys edulis against palmitic acid (PA)-induced lipoapoptosis. The lipo-detoxification function of the bamboo extract (BEX) was evaluated using cell culture models. Cell viability was measured by MTT assay and cell apoptosis was monitored by Annexin V staining. Cellular uptake of fluorescent free fatty acid (FFA) analog was measured by flow cytometry. Protein levels of total protein kinase B (Akt) and phosphorylated Akt (p-Akt) were measured by western blotting. The results show that co-incubating BEX with mouse myoblast C2C12 cells had no effect on the cellular uptake of FFA, but dramatically decreased PA-induced cell apoptosis and protected cell viability. A similar antilipotoxicity effect of BEX was observed in other mammalian cells. BEX significantly decreased the protein levels of both Akt and p-Akt in C2C12 cells under normal cell culture conditions but not under lipotoxic conditions, indicating the regulatory effect of BEX on cell signaling pathways and its response to a high FFA environment. This study demonstrated a novel function of bamboo extract in preventing lipotoxicity in mammalian cells, implicating a promising phytotherapeutic approach for lipo-detoxification. 相似文献
63.
PB Greer K Dahl MA Ebert M White C Wratten P Ostwald P Pichler JW Denham 《Journal of Medical Imaging and Radiation Oncology》2008,52(5):517-524
The aims of this study were to investigate whether intrafraction prostate motion can affect the accuracy of online prostate positioning using implanted fiducial markers and to determine the effect of prostate rotations on the accuracy of the software‐predicted set‐up correction shifts. Eleven patients were treated with implanted prostate fiducial markers and online set‐up corrections. Orthogonal electronic portal images were acquired to determine couch shifts before treatment. Verification images were also acquired during treatment to assess whether intrafraction motion had occurred. A limitation of the online image registration software is that it does not allow for in‐plane prostate rotations (evident on lateral portal images) when aligning marker positions. The accuracy of couch shifts was assessed by repeating the registration measurements with separate software that incorporates full in‐plane prostate rotations. Additional treatment time required for online positioning was also measured. For the patient group, the overall postalignment systematic prostate errors were less than 1.5 mm (1 standard deviation) in all directions (range 0.2–3.9 mm). The random prostate errors ranged from 0.8 to 3.3 mm (1 standard deviation). One patient exhibited intrafraction prostate motion, resulting in a postalignment prostate set‐up error of more than 10 mm for one fraction. In 14 of 35 fractions, the postalignment prostate set‐up error was greater than 5 mm in the anterior–posterior direction for this patient. Maximum prostate rotations measured from the lateral images varied from 2° to 20° for the patients. The differences between set‐up shifts determined by the online software without in‐plane rotations to align markers, and with rotations applied, was less than 1 mm (root mean square), with a maximum difference of 4.1 mm. Intrafraction prostate motion was found to reduce the effectiveness of the online set‐up for one of the patients. A larger study is required to determine the magnitude of this problem for the patient population. The inability in the current software to incorporate in‐plane prostate rotations is a limitation that should not introduce large errors, provided that the treatment isocentre is positioned near the centre of the prostate. 相似文献
64.
Wang PS Gilman SE Guardino M Christiana JM Morselli PL Mickelson K Kessler RC 《Medical care》2000,38(9):926-936
OBJECTIVE: Greater understanding of the help-seeking process is needed to reduce the level of unmet need for mental health treatment. DESIGN: Cross-sectional mail survey. STUDY POPULATION: The study population consisted of 3,516 respondents to a survey of members of 14 patient advocacy groups in 11 countries. Respondents reported whether they initiated and adhered to the treatment most recently recommended to them. OUTCOMES: Crude and adjusted likelihoods of initiating and adhering to recommended treatment were studied. RESULTS: The vast majority of respondents reported initiating the most recent treatment recommended to them (94%), and most of those who initiated treatment also adhered to such treatment (83%). Predictors of initiation by the respondents included higher levels of education, having pharmacotherapy recommended to the respondent, and having received explanations about the diagnosis and treatment. Predictors of adherence to therapy included male gender, receipt of pharmacotherapy, and presence of insurance coverage. Side effects were an important reported reason for treatment dropout, with 44% of respondents reporting lifetime treatment dropout due to side effects. CONCLUSIONS: Successful initiation and adherence to mental health treatments depend critically on patients' knowledge and awareness, clinicians' communication skills, treatment side effects, and barriers such as lack of insurance. Further study and intervention focused on these modifiable factors are needed to improve the adequacy of mental health treatment. 相似文献
65.
Gilman BH 《Health economics》2000,9(4):277-294
Recent research has warned that the introduction of Diagnosis Related Groups (DRGs) based on hospital treatment decisions will lead to an increase in the rate of marginal procedures and to a resumption of high medical expenditure growth rates. This paper explores the often contradictory effects of the multiple reimbursement incentives created by refinements to the Prospective Payment System (PPS) (principally, the introduction of procedure-based DRGs) on hospital resource allocation. Three effects are examined in the paper: (i) the change in primary or payment-related procedures owing to marginal reimbursement incentives; (ii) the change in secondary or non-payment-related services owing to average price incentives; and (iii) the change in average severity of both medical and surgical admissions. The model suggests that the anticipated positive effect of marginal reimbursement incentives on overall hospital resource use may be offset by several factors, most notably the lower average payment incentives of non-procedural DRGs. 相似文献
66.
S Muralidhar M Gulati B Kumar SK Sharma K Suman PB Roy 《Journal of Medical Imaging and Radiation Oncology》1996,40(2):106-108
A study was undertaken to determine the usefulness of ultrasonography as an investigative tool, and its role in deciding the management of Peyronie's disease. Fifteen patients with Peyronie's disease were studied by ultrasonography. The plaque could be demonstrated in all patients. The dimensions of the plaque varied from less than 1 cm to more than 7cm in length and 2-4mm in thickness. The disease was active in 26% of the patients, as indicated by the presence of hypoechoic areas around a central region of hyperechoism. Ultrasonogram was more accurate than clinical assessment in delineating the extent of lesions. In one-third of the patients, sonography demonstrated the plaques to be more extensive than had been detected by clinical examination. Calcification and activity of disease (which are clearly defined by ultrasonogram) are determining factors in the management of Peyronie's disease. This information allows the surgeon to select the modality of treatment, the timing of surgery and extent of excision. Thus, ultrasonography plays a vital role in the preliminary investigation and management of Peyronie's disease. 相似文献
67.
B R Elejalde M Mercedes de Elejalde M Gilman 《American journal of obstetrics and gynecology》1985,151(5):666-670
We have used xeroradiography to study normal and abnormal fetuses including some with anencephaly, hydrocephalus, spina bifida, osteogenesis imperfecta (type IV), Jeune syndrome, radial aplasia, thanatophoric dysplasia, and Pena-Shokeir syndrome. Xeroradiography images the lines of ossification and epiphyses in great detail, shows ossification, and reveals abnormalities that alter bone modeling as seen in Jeune syndrome, osteogenesis imperfecta (type IV), and thanatophoric dysplasia. This technique can be used successfully to examine soft tissues and organs. It can also be used in combination with contrast materials to identify the lateral ventricles, the cardiovascular, gastrointestinal, urinary, and respiratory systems, and the cavities (pleural and peritoneal) of the fetal body. 相似文献
68.
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70.
Long-term tolerability and efficacy of lamotrigine in pediatric patients with epilepsy 总被引:1,自引:0,他引:1
Duchowny M Gilman J Messenheimer J Womble G Risner M;LAMICTAL Pediatric Study Group 《Journal of child neurology》2002,17(4):278-285
Accumulating data suggest that the antiepilepsy drug lamotrigine, which has been available for adult use for more than a decade, also confers broad-spectrum, well-tolerated control of epilepsy in children. The current study--the open-label continuation phase of several short-term clinical trials--was conducted to assess the long-term tolerability and efficacy of lamotrigine as open-label adjunctive therapy or monotherapy in pediatric patients for a variety of seizure types and syndromes including partial seizures, absence seizures, and Lennox-Gastaut syndrome. Clinic visits occurred every 24 weeks throughout the treatment period. A total of 252 patients under 16 years of age were enrolled in the study. The numbers of patients exposed to at least 48 weeks, 96 weeks, and 144 weeks of treatment with lamotrigine were 185 (73.4%), 119 (47.2%), and 60 (23.8%), respectively, for an average duration of exposure of 96.7 weeks. The most common adverse events considered by the investigator to be drug related were dizziness (9.1%), somnolence (7.9%), nausea (6.3%), vomiting (5.2%), and headache (5.2%). The most common serious adverse events (regardless of suspected cause) included pneumonia (3.0%) and infection (1.9%). Investigators judged that the overall clinical status of three-fourths of the patients had improved at treatment weeks 48 and 96 relative to prelamotrigine clinical status. Lamotrigine administered as monotherapy or adjunctive therapy for an average of 2 years (96.7 weeks) was well tolerated and effective in pediatric patients with partial or generalized epilepsy. These results complement and extend the large body of data demonstrating the tolerability and efficacy of lamotrigine with short- and long-term use in adults. 相似文献