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101.
目的 建立急性分离果蝇成虫中枢神经细胞技术,并记录分析其钾电流。方法 取S、R或H品系果蝇成虫3—5只,分离出果蝇脑组织。胶原酶消化处理后,加入10%的胎牛血清果蝇培养基终止酶反应。巴氏吸管吹打,细胞悬液静置1h后用于电生理实验。全细胞电压钳记录并分析其外向钾电流。结果 酶消化法成功急性分离出果蝇成虫中枢神经细胞。85%以上为Ⅱ型神经细胞,少部分为Ⅰ型和Ⅲ型神经细胞。记录到快失活与持续复合型、慢失活型、快失活和持续型四种全细胞钾电流。结论 本技术可成功急性分离三品系果蝇成虫中枢神经细胞,并记录到四种钾电流。 相似文献
102.
103.
类风湿关节炎和骨质疏松在我国都属于常见病和多发病,而二者之间又有着非常重要的联系。但是目前临床上还没有一个广泛应用的药物可以同时对两者都产生很好的治疗效果。为了进一步了解骨质疏松和类风湿关节炎的关系,将来能够找到更好的治疗药物,笔者从流行病学、发病机制以及治疗方法等方面分别进行了论述。 相似文献
104.
105.
目的 探讨华南地区某眼科医院感染性角膜炎的病原菌谱及其特点。方法 回顾性系列病例研究。选择2013年7月1日至2017年12月31日在中山大学中山眼科中心进行角膜取材和微生物检测的角膜感染患者3 914例。表面麻醉后刮取病灶边缘的病灶组织,进行细菌、真菌培养及鉴定。培养结果阳性的细菌采用生化比色或质谱进行种属鉴定;真菌依据形态学进行种属鉴定。各季节菌谱阳性率差异比较采用卡方检验。结果 感染性角膜炎患者中,男2 468例(63.1%),女1 446例(36.9%),年龄(49.5±16.8)岁。病原菌培养阳性的患者共1 673例(42.7%),其中单纯细菌749例(44.8%),单纯真菌849例(50.7%),混合感染75例(4.5%)。最常见的细菌是葡萄球菌属(20.1%),其次是假单胞菌属(7.5%);最常见的真菌是镰刀菌属(25.5%),其次是曲霉菌属(10.3%)。细菌的阳性率在5-8月明显高于1-2月和9-12月(P<0.05),真菌的阳性率在5-6月明显低于1-2月和9-12月(P<0.05)。结论 在华南地区一所三甲眼科医院的感染性角膜炎中,真菌感染略高于细菌感染,且细菌和真菌感染存在季节性差异。 相似文献
106.
Joseph H. Liao MD Hernan Jara PhD Rohini Nadgir MD Elliott Elias MD Nekou Nowrouzi Naoko Saito MD Martin H. Steinberg MD Osamu Sakai MD PhD 《Journal of magnetic resonance imaging : JMRI》2013,37(5):1182-1188
Purpose:
To identify and characterize sickle cell disease (SCD)‐related changes in the composition of mandibular bone marrow using qMRI relaxometry histograms.Materials and Methods:
Thirteen SCD patients and 17 controls underwent brain MR imaging with the mixed turbo spin‐echo (TSE) pulse sequence at 1.5T. The mandible was manually segmented and divided into body, angle, ramus, and condyle. T1 and T2 histograms of each mandible were modeled with Gaussian functions. The relaxation time histogram peaks were calculated, and the number of monomodal versus bimodal curves was compared.Results:
SCD patients exhibited monomodal distributions on both T1 and T2 histograms, consistent with a composition of predominantly red hematopoietic marrow. Eighty‐eight percent of mandibles in control subjects exhibited a bimodal distribution in T1 and all showed a bimodal distribution in T2, indicating mixed but predominantly yellow marrow composition. The second peak in control subjects was shorter in T1 and longer in T2, consistent with yellow marrow composition.Conclusion:
Instead of physiological fatty replacement, SCD patients exhibit red marrow persistence in the mandible, likely due to the increased demand for hematopoiesis. This phenomenon can be manifested by a monomodal curve in both T1 and T2 relaxometric histograms. J. Magn. Reson. Imaging 2013;37:1182–1188. © 2012 Wiley Periodicals, Inc. 相似文献107.
ObjectiveStudies have shown that some specific body measures are associated with the occurrence of cancers. Few studies have demonstrated the relationship with more comprehensive approaches. This study aims to explore body measures and the combinations associated with internal organ cancers.MethodsThree-dimensional anthropometric body surface scanning data collected 10,215 participants from the health examination department in a medical center of Taiwan during 2000–2010. Follow-up was conducted for an average of 8 years, and 244 internal organ cancer cases were identified.ResultsAn increased risk of internal organ cancers was observed among the subjects with larger waist circumference/smaller thigh circumference, in which waist-to-thigh ratio (WTR) was constructed. Comparing the subjects in the fourth quartile for WTR to the subjects in the first quartile with multiple Cox regression analysis yielded a hazard ratio of 1.842 (95% confidence interval, 1.131~2.999). The association between WTR quartile and internal organ cancers was stronger among male participants, older participants, and participants with chronic conditions.ConclusionsThe study has revealed that WTR is the most significant predictor for the occurrence of cancer in Asian populations. Because it is easy to measure and open to modification, WTR may be more useful in clinical and preventive medicine in the future. 相似文献
108.
摘 要 目的:考察影响水杨酸滴丸制备的因素,确立其最佳成型工艺。方法: 考察环境因素、加热温度、基质配比与试验步骤对滴丸制备工艺的影响。以丸重差异、溶出时限及外观质量为综合评价指标,通过正交试验进一步优化滴丸的制备工艺。结果: 基质单独加热熔化后再与药液在避光密封的条件下进行混合,可防止药液迅速氧化变红。滴丸的最佳制备工艺为:聚乙二醇400与聚乙二醇6000的比例为1∶5,药液温度为50℃,滴距为8 cm,滴制速度为70滴·min-1。结论:该工艺简单可行,制得滴丸的丸重差异、溶出时限及外观质量均符合质量要求。 相似文献
109.
Liao Xiang-bin廖翔嫔 Zhang Ji-hong张季鸿 Lu Xue-ying路雪英and Sui Shu-jing隋淑静 Tianin Children''s Hospital Tianjin 《中华医学杂志(英文版)》1984,97(2):141-142
1,330 autopsies performed at the Pathology
Department of this hospital during 1958.-1981,
including 415 newborns, a.re studied. Among
the 371 cases of congenital anomalies (110 new-
borns), 173 were congenital cardiovascular
anomalies (66 newborns), a 13% morbidity
forming 46.5'70 0f all congenital anomalies seen.
The 66 nowborns were 6070 0f all neonatal clan-
genital anamalies and 38.2To of all cardiovascular
anomaLies. Fetal stage diagnosis and early ter-
mination of pregnancy when necessary is the
treatment of choice. 相似文献
110.
OBJECTIVE: 18F-fluorodeoxyglucose positron emission tomography (FDG-PET) [or PET/computed tomography (CT)] is more likely to show false-negative results when it is performed shortly after chemotherapy and/or radiotherapy because of "metabolic stunning". The present study aimed to evaluate the influence of I-131 therapy on FDG uptake and the detection of recurrence or metastasis of differentiated thyroid cancer (DTC). METHODS: We retrospectively enrolled 16 consecutive FDG-PET/CT studies which had been performed in patients with DTC with elevated thyroglobulin (TG) but negative I-131 whole-body scan. All studies were performed under L: -thyroxine suppression. The patients were divided into groups A and B for PET/CT performed within 4 months of I-131 therapy or no such therapy, respectively. Each lesion identified on PET/CT was characterized using a 5-point scale by visual analysis: 0 = definitely benign, 1 = probably benign, 2 = equivocal, 3 = probably malignant, and 4 = definitely malignant. The maximum standardized uptake value (SUV max) in each lesion was also measured for semiquantitative analysis. We compared the visual grading and SUV max of the lesion of highest FDG uptake between groups A and B. RESULTS: For visual analysis, group B had significantly more patients with an uptake score of 3 or 4 than group A (80% vs. 17%, P = 0.01). In addition, there were significantly more equivocal results from group A than from group B (67% vs. 10%, P = 0.02). If the patients with the highest uptake scores of 2, 3, and 4 were considered to be positive for local recurrence or metastasis, there would be no significant difference between the positive rates of groups A and B (83% vs. 90%, P = 0.7). However, the mean SUV max of positive results was significantly lower for group A than for group B (3.1 +/- 0.9 and 6.6 +/- 3.5, respectively, P = 0.02). CONCLUSIONS: The preliminary results suggested that FDG uptake in DTC may be negatively influenced by I-131 therapy within 4 months, resulting in lower FDG uptake and more equivocal results. Further studies are necessary to determine whether it is secondary to "metabolic stunning" caused by I-131 therapy. 相似文献