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61.
18F-氟赤式硝基咪唑肿瘤乏氧显像实验研究 总被引:4,自引:0,他引:4
目的 探讨18F-氟赤式硝基咪唑(FETNIM)在肿瘤乏氧诊断中的应用价值.方法 30只SPCA-1人肺腺癌荷瘤BALB/c裸鼠采用随机数字表法分为A和B 2组(鼠数分别为16和14只).尾静脉注射37 MBq18F-FETNIM后A组分别于注射后0.5,1,2,3 h处死裸鼠,取血液、肺、心、肝、脾、肾、肿瘤等组织测量质量,用γ计数仪测定放射性计数,计算每克组织百分注射剂量率(%ID/g);B组用PO2微电极测量肿瘤组织内乏氧情况.结果 18F-FETNIM在肾中代谢最高,在脂肪和骨骼中代谢较低,肿瘤/正常组织的放射性比值较高,且随时间而增加,2 h达最高,肿瘤/血液放射性比值为1.69±0.37,肿瘤/肌肉放射性比值为1.57±0.47.HE染色显示瘤内有大量的乏氧坏死组织.组织内PO2微电极测量示肿瘤内均有乏氧,肿瘤内PO,1.1~27.7 mm Hg(1 mm Hg=0.133 kPa).结论 18F-FETNIM在荷瘤裸鼠体内具有较低的外周代谢,脂溶性较低,能被肿瘤乏氧组织摄取,可用于肿瘤乏氧诊断. 相似文献
62.
利尿性肾图在评估小儿上尿路扩张术后疗效中的价值 总被引:4,自引:0,他引:4
目的 探讨利尿性肾图 (DR)在评估小儿上尿路扩张术后疗效中的价值。 方法 对5 4例 (6 6侧 )上尿路扩张术后患儿随访资料进行回顾性分析。 结果 5 4例患儿根据肾血流灌注率(BPR)值分为轻、中、重度三组。轻、中度组 (49侧 )肾图术前为无排泄相的梗阻图型 ,术后排泄相出现 ,其中注射速尿后明显下降者 37侧 ,无变化 12侧。重度组 (17侧 )BPR术前为 (2 3.8± 3.5 ) % ,术后为 (33.4± 6 .4 ) % ,差别有显著性意义 (P <0 .0 1)。肾图术前为低平的梗阻图型 ,术后吸收排泄相有所改善 ,注射速尿后曲线加快下降者 10侧 ,无变化 7侧。 2例术后 2周和 4 0d复查DR ,肾图曲线由术前排泄延迟型转为梗阻型 ,半年后又转为排泄延迟型。 结论 肾图曲线变化是判断轻、中度上尿路扩张术后疗效的重要指标。BPR是判断重度上尿路扩张术后肾功能恢复的重要指标。DR随访时间以术后半年为宜 相似文献
63.
AIMS—To evaluate the inferior to temporal neuroretinal rim width ratio and superior to temporal rim width ratio as measures of rim shape for diagnosis of glaucoma.
METHODS—Colour stereo optic disc photographs of 527 normal subjects, 100 ocular hypertensive individuals with normal visual fields, and 202 open angle glaucoma patients with a mean perimetric defect of less than 10 dB were morphometrically evaluated. Eyes with an optic cup area of < 0.2 mm2 were excluded.
RESULTS—In the normal subjects, inferior to temporal rim width ratio (1.67 (SD 0.53)) was significantly (p<0.0001) higher than superior to temporal rim width ratio (1.56 (0.49)). Both ratios were significantly (p<0.0001) higher the more vertically the optic disc was configured. In the normal eyes, both ratios were statistically independent of disc size, rim area, refractive error, age, and sex. With the differences being more marked for the inferior to temporal ratio than for the superior to temporal ratio, both rim width ratios were significantly (p<0.005) lower in the ocular hypertensive group than in the normal group. Despite the high significance of the differences, diagnostic power of the inferior ratio and the superior ratio was 59% and 58%, respectively, indicating a marked overlap between the groups.
CONCLUSIONS—Abnormally low inferior to temporal and superior to temporal rim width ratios can indicate glaucomatous optic nerve damage in some ocular hypertensive eyes. Being independent of optic disc size and ocular magnification, the rim width ratios may be taken as one among other variables for the ophthalmoscopic optic disc evaluation, taking into account, however, a pronounced overlap between normal eyes and ocular hypertensive eyes.
Keywords: neuroretinal rim width ratios; glaucoma; ocular hypertension 相似文献
METHODS—Colour stereo optic disc photographs of 527 normal subjects, 100 ocular hypertensive individuals with normal visual fields, and 202 open angle glaucoma patients with a mean perimetric defect of less than 10 dB were morphometrically evaluated. Eyes with an optic cup area of < 0.2 mm2 were excluded.
RESULTS—In the normal subjects, inferior to temporal rim width ratio (1.67 (SD 0.53)) was significantly (p<0.0001) higher than superior to temporal rim width ratio (1.56 (0.49)). Both ratios were significantly (p<0.0001) higher the more vertically the optic disc was configured. In the normal eyes, both ratios were statistically independent of disc size, rim area, refractive error, age, and sex. With the differences being more marked for the inferior to temporal ratio than for the superior to temporal ratio, both rim width ratios were significantly (p<0.005) lower in the ocular hypertensive group than in the normal group. Despite the high significance of the differences, diagnostic power of the inferior ratio and the superior ratio was 59% and 58%, respectively, indicating a marked overlap between the groups.
CONCLUSIONS—Abnormally low inferior to temporal and superior to temporal rim width ratios can indicate glaucomatous optic nerve damage in some ocular hypertensive eyes. Being independent of optic disc size and ocular magnification, the rim width ratios may be taken as one among other variables for the ophthalmoscopic optic disc evaluation, taking into account, however, a pronounced overlap between normal eyes and ocular hypertensive eyes.
Keywords: neuroretinal rim width ratios; glaucoma; ocular hypertension 相似文献
64.
William B. White Yusra Anis Anwar George A. Mansoor Domenic A. Sica 《American journal of hypertension》2001,14(12):365-1255
BACKGROUND: Eprosartan is a new nonphenyl angiotensin II receptor blocker, which has been approved for the treatment of hypertension. Although the drug has a relatively short plasma half-life of 5 to 9 h, clinical studies have suggested that its antihypertensive effect persists for 24 h. METHODS: We assessed both the changes in 24-h and trough blood pressure (BP) (last 4 h of the ambulatory BP while the patient was awake) of eprosartan at doses of 600 and 1,200 mg once daily in a randomized, double-blind, placebo-controlled trial. Ambulatory BP was monitored at placebo baseline and after 8 weeks of double-blind therapy. RESULTS: Two hundred patients randomized in the study with 177 patients completing the trial. The 24-h change in BP from baseline was 0.2/0.1 +/- 1.4/1.0 mm Hg, -7.9/ -5.4 +/- 1.0 mm Hg (P < .0001), and -7.4/-5.0 +/- 0.9 mm Hg (P < .0001) in the placebo, 600-mg eprosartan, and 1,200-mg eprosartan groups, respectively. Changes in trough ambulatory BP showed significant reductions of -6.3/-4.1 +/- 1.6/1.1 mm Hg and -7.7/-5.5 +/- 1.5/1.0 mm Hg for 600 mg of eprosartan and 1,200 mg of eprosartan, respectively. CONCLUSIONS: These data demonstrate that eprosartan at doses of 600 or 1200 mg significantly reduced BP throughout an entire 24-h dosing period. There were no differences between the 600- and 1,200-mg dose; thus, 600 mg once daily should be the only dose used in the treatment of hypertension with eprosartan. 相似文献
65.
Pineals from male Long-Evans rats (60-65 days old; adapted to a 0700-1900 photoperiod) were cultured for 6 h either in light (1200-1800) or in dark (1800-2400). The objective was to ascertain the effects of tryptophan (trp) and phenylalanine (phe) levels and ratios in the culture medium on melatonin levels in the pineals and their respective media. Total culture (pineal + medium) melatonin levels, determined by RIA, were similar under all conditions. However, in cultures during the early dark phase (1800-2400) lower trp:phe ratios in the medium led to lower pineal:medium ratios of melatonin content. In cultures during the late light phase (1200-1800) the trp:phe ratio had little impact on the pineal:medium distribution of melatonin. Trp:phe ratio rather than absolute level of either amino acid appeared responsible for this effect. Functionally this means that during early dark phase, but not late light phase, movement of melatonin from cultured pineal to medium is progressively facilitated by lower trp:phe ratios. It remains to be determined to what extent darkness per se and/or endogenous pineal rhythmic mechanisms have a permissive role in the action of trp:phe ratio on pineal melatonin release. A melatonin compartmentalization/release effect of these or other amino acids, or their ratios, has not been reported previously and may possibly contribute to mechanisms for melatonin's transport or release at night. 相似文献
66.
67.
We have studied blood glucose concentrations 2 h after a 75g glucose load, and glycohaemoglobin as assayed by agar gel electrophoresis, in 1084 subjects over the age of 40 in a community screening survey. There were 16 newly diagnosed diabetic women (2.7%) and 11 men (2.5%). The mean level of 2h blood glucose was 5.6 +/- 2.04 mmol/l in women and 5.33 +/- 2.14 mmol/l in men (p less than 0.002) but when corrected for age and weight the mean levels were 5.55 mmol/l in women and 5.40 mmol/l in men (p greater than 0.2). Mean levels of glycohaemoglobin were 7.30 +/- 1.10% in women and 7.17 +/- 1.18% in men (p less than 0.02) but when adjusted for blood glucose and age these were 7.25% in both sexes (p greater than 0.9). Differences in glucose tolerance in this population are related to differences in age and weight. There is no evidence for differences in glycosylation in men and women. 相似文献
68.
Michael A. Kohn MD MPP Kristi Kerr MD David Malkevich MD Nelda O''Neil RN M. James Kerr MS Beth C. Kaplan MD 《Academic emergency medicine》2003,10(2):119-126
Strategies for diagnosing ectopic pregnancy that defer endovaginal ultrasound in women with suggestive symptoms and serum beta-human chorionic gonadotropin (beta-hCG) levels less than 1500 mIU/mL ignore the increased risk of ectopic pregnancy in these patients. OBJECTIVE: To quantify this increased risk by establishing and comparing the beta-hCG distributions of symptomatic women with ectopic pregnancies, abnormal intrauterine pregnancies, and normal intrauterine pregnancies. METHODS: The authors reviewed the records of a cohort of women who visited an urban emergency department (ED) during a 34-month period with abdominal pain or vaginal bleeding and non-zero quantitative beta-hCG levels. Explicit criteria were used to determine whether the pregnancy ultimately turned out to be intrauterine and normal, intrauterine and abnormal, or ectopic. Probability distributions were compared using frequency distributions, receiver operating characteristic (ROC) curves, and likelihood ratios. RESULTS: Of 730 ED patients included in the analysis, 96 (13%) had ectopic pregnancies, 253 (35%) had abnormal intrauterine pregnancies, and 381 (52%) had normal intrauterine pregnancies. The beta-hCG distributions of patients with ectopic pregnancies and abnormal intrauterine pregnancies were similar and much lower than the beta-hCG distribution of patients with normal intrauterine pregnancies. A beta-hCG level less than 1500 mIU/mL more than doubled the odds of ectopic pregnancy (likelihood ratio = 2.24). Of the 158 patients with beta-hCG below 1500 mIU/mL, 40 (25%; 95% confidence interval [CI] = 19% to 32%) had ectopic pregnancies, and only 25 (16%; CI = 11% to 22%) had normal intrauterine pregnancies. CONCLUSIONS: In women with pain or bleeding and serum beta-hCG levels less than 1500 mIU/mL, the risk of ectopic pregnancy is substantially increased, while the likelihood of normal intrauterine pregnancy is low. 相似文献
69.
《Journal of infection and chemotherapy》2022,28(10):1364-1369
IntroductionPneumococcal pneumonia has a high morbidity and mortality in adults, especially those ≥65 years old. In the past decade, pneumococcal vaccination programs have been initiated worldwide, however, few data concerning mortality changes are available in pneumococcal pneumonia patients and there are no reports clarifying these current changes in Japan.MethodsJapanese patients ≥65 years old hospitalized with pneumococcal pneumonia between April 2012 and March 2018 were analyzed using the Diagnostic Procedure Combination database. In-hospital mortality was evaluated, and the odds ratios for this outcome in each fiscal year compared with that in 2012 was analyzed using multivariable logistic regression models.ResultsBetween 2012 and 2017, data of 47,375 pneumococcal pneumonia patients ≥65 years old were extracted. The incidence per 1000 person-years for in-hospital mortality was 60.4 in 2012, 56.8 in 2013, 63.2 in 2014, 56.1 in 2015, 73.0 in 2016, and 67.4 in 2017 and the odds ratios for in-hospital mortality in 2013, 2014, 2015, 2016, and 2017 compared with that in 2012 were 1.00, 1.05, 1.04, 1.06, and 0.98, respectively. There were no significant differences between 2012 and each year from 2013 to 2017. Low BMI; low ADL score; high A-DROP score; comorbid malignancy and heart failure; the coexistence of invasive pneumococcal infection; and the use of invasive mechanical ventilation were independent risk factors for in-hospital mortality.ConclusionsThere were no changes in in-hospital mortality in pneumococcal pneumonia patients between 2012 or each year from 2013 to 2017 and further epidemiological observations are necessary. 相似文献