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Edouard J. Trabulsi MD William G. Merriam MD Leonard G. Gomella MD 《Current Prostate Reports》2006,4(2):67-72
Correct staging of prostate cancer at initial diagnosis, as well as accurate staging and tumor localization with biochemical recurrence, remains generally inaccurate with current imaging techniques. Newer modalities are being investigated to accurately identify patients with prostate cancer at different stages of disease. Identification of locally recurrent disease or distant metastasis at the time of biochemical failure after local therapy will help guide treatment options and avoid potentially toxic salvage therapies in patients who will not benefit. A review of prostate cancer imaging literature over the past 12 months was performed to identify emerging imaging modalities that may be beneficial in the management of prostate cancer. Enhanced transrectal ultrasonography modalities, including ultrasound contrast agents, color and power Doppler, and elastrography, have demonstrated incremental benefit when combined with standard grayscale ultrasonography to accurately target and diagnose prostate cancer. Endorectal MRI, with contrast enhancement and spectroscopic imaging, shows promise in the initial staging of prostate cancer prior to local therapy. The use of positron-emission tomography scan for prostate cancer remains to be defined, but may help delineate the site of recurrence with biochemical failure after local therapy. Several new imaging modalities show promise for the evaluation of the patient with prostate cancer. Enhanced ultrasonography techniques may prove to be more accurate in diagnosing prostate cancer over standard gray-scale ultrasonography. Accumulating evidence supports the use of endorectal MRI and spectroscopy to help treatment planning with either surgical or radiotherapeutic approaches. Although intriguing, the available data for positron-emission tomography in prostate cancer remains too shallow to advocate routine use. 相似文献
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BACKGROUND & AIMS: Nutrients and properties of lipases affect survival of lipolytic activity during aboral gastrointestinal transit. Whether different doses and formulations of bacterial lipase and diets affect steatorrhea was tested in pancreatic-insufficient dogs. METHODS: A dose of 0-600,000 IU of powdered and 135,000 and 300,000 IU of liquid bacterial lipase was given with a standard meal to 5 dogs with ligated pancreatic ducts. In 4 dogs, 0 or 300,000 IU (normal 6-hour postprandial amount) of powder bacterial lipase was also given with five meals containing 850 kcal with different nutrient caloric densities (mixture design). Coefficients of fat absorption during 72- hour fecal balance studies were used to assess treatments. RESULTS: With the standard meal, powder bacterial lipase reduced steatorrhea in a dose-dependent manner (P = 0.03), and 135,000 and 300,000 IU of the liquid form decreased steatorrhea more than powder bacterial lipase (P = 0.017 and 0.057, respectively). Coefficients of fat absorption with 300,000 IU of powder bacterial lipase correlated (r2 = 0.79; P < 0.001) with increasing proportions of fat calories in diets. CONCLUSIONS: Liquid bacterial lipase decreases steatorrhea more than powder, and 300,000 IU of powder bacterial lipase ingested with high-fat meals corrects canine pancreatic steatorrhea. The combination of adequate mixing of small amounts (milligrams) of bacterial lipase and high-fat meals abolishes canine steatorrhea and may abolish human pancreatic steatorrhea. (Gastroenterology 1997 Jun;112(6):2048-55) 相似文献
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A randomized controlled trial of electromagnetic therapy in the primary care management of venous leg ulceration 总被引:1,自引:1,他引:0
OBJECTIVE: The aim was to establish the potential efficacy, tolerabilityand side-effect profile of electromagnetic therapy as an adjunctto conventional dressings in the treatment of venous leg ulcers. METHOD: A prospective, randomized, double blind controlled clinicaltrial was carried out in a dedicated leg ulcer clinic basedin one urban general practice. Nineteen patients with leg ulcersof confirmed venous aetiology were assessed. The main outcomemeasures were rate and scale of venous leg ulcer healing, changesin patient-reported pain levels, quality of life, degree ofmobility, side effect profile and acceptability to patientsand staff. RESULTS: Sixty-eight per cent of patients attending this dedicated clinicachieved improvements in the size of their ulcer (4, 21%, healedfully) and in reduced pain levels (P < 0.05) during the trial,despite the chronicity of ulcer histories. Patients treatedwith electromagnetic therapy at 800 Hz were found at day 50to have significantly greater healing (P < 0.05) and paincontrol (P < 0.05) than placebo therapy or treatment with600 Hz. All patients reported improved mobility at the end ofthe study. The electromagnetic therapy was well tolerated bypatients, with no differences between groups in reporting adverseevents, and proved acceptable to staff. CONCLUSION: Despite the small numbers in this pilot study, electromagnetictherapy provided significant gains in the healing of venousleg ulcers and reduction in pain. Keywords. Electromagnetic therapy, RCT, leg ulcers, primary care. 相似文献
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Porter JD Merriam AP Leahy P Gong B Feuerman J Cheng G Khanna S 《Human molecular genetics》2004,13(3):257-269
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Olendzki B Hurley TG Hebert JR Ellis S Merriam PA Luippold R Rider L Ockene IS 《Journal of the American Dietetic Association》1999,99(11):1433-1439
The Dietary Risk Assessment (DRA) is a brief dietary assessment tool used to identify dietary behaviors associated with cardiovascular disease. Intended for use by physicians and other nondietitians, the DRA identifies healthful and problematic dietary behaviors and alerts the physician to patients who require further nutrition counseling. To determine the relative validity of this tool, we compared it to the 7-Day Dietary Recall (an instrument developed to assess intake of dietary fat) and to the average of 7 telephone-administered 24-hour dietary recalls. Forty-two free-living subjects were recruited into the study. The 7-Day Dietary Recall and DRA were administered to each subject twice, at the beginning and the end of the study period, and the 24-hour recalls were conducted during the intervening time period. Correlation coefficients were computed to compare the food scores derived from the 3 assessment methods. Correlations between the DRA and 7-Day Dietary Recall data were moderate (r = .47, on average, for postmeasures); correlations between the DRA and 24-hour recalls were lower. The ability of the DRA to assess dietary fat consumption and ease of administration make it a clinically useful screening instrument for the physician when counseling patients about dietary fat reduction. 相似文献
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Epidemiological studies have correlated cortical cataract with exposure to light and have suggested that this is due primarily to relatively short wavelengths of ultraviolet radiation (UV-B). In addition, some cellular and animal models also implicate UV-B. In order to evaluate the likely role of different wavelengths of light in the etiology of cortical cataracts, the optical characteristics of several animal models were ascertained and compared to the primate. This study shows that the mouse model absorbs UV-B almost exclusively whereas other animal models such as the rabbit and the guinea pig also contain chromophores that absorb UV-A. The absorptive characteristics of the human lens varies drastically with age. The young lens absorbs primarily UV-A, whereas with age, there are increases in absorptions at 320 nm and out to wavelengths as long as 550 nm. By sectioning human lenses it was found that these changes in absorption properties increased toward the central and the nuclear regions.These absorptive characteristics were then compared to the amount of light reaching the surface of the lens. It was found that UV-B is a minor component of total energy reaching the surface of the human lens and old human lens proteins absorb 2 orders of magnitude more UV-A and visible light than UV-B. It is concluded that it is premature to exclude UV-A or even visible light in the etiology of human cortical cataracts. 相似文献