全文获取类型
收费全文 | 79345篇 |
免费 | 6900篇 |
国内免费 | 4611篇 |
专业分类
耳鼻咽喉 | 927篇 |
儿科学 | 976篇 |
妇产科学 | 791篇 |
基础医学 | 9866篇 |
口腔科学 | 1380篇 |
临床医学 | 8726篇 |
内科学 | 11631篇 |
皮肤病学 | 1415篇 |
神经病学 | 3947篇 |
特种医学 | 3899篇 |
外国民族医学 | 21篇 |
外科学 | 7986篇 |
综合类 | 12087篇 |
现状与发展 | 28篇 |
一般理论 | 7篇 |
预防医学 | 5355篇 |
眼科学 | 2356篇 |
药学 | 8653篇 |
67篇 | |
中国医学 | 3936篇 |
肿瘤学 | 6802篇 |
出版年
2024年 | 189篇 |
2023年 | 976篇 |
2022年 | 2474篇 |
2021年 | 3462篇 |
2020年 | 2475篇 |
2019年 | 2269篇 |
2018年 | 2460篇 |
2017年 | 2324篇 |
2016年 | 2465篇 |
2015年 | 3697篇 |
2014年 | 4586篇 |
2013年 | 4544篇 |
2012年 | 6672篇 |
2011年 | 7066篇 |
2010年 | 4662篇 |
2009年 | 4018篇 |
2008年 | 5012篇 |
2007年 | 4724篇 |
2006年 | 4459篇 |
2005年 | 3933篇 |
2004年 | 2972篇 |
2003年 | 2975篇 |
2002年 | 2479篇 |
2001年 | 1683篇 |
2000年 | 1401篇 |
1999年 | 1255篇 |
1998年 | 796篇 |
1997年 | 701篇 |
1996年 | 601篇 |
1995年 | 542篇 |
1994年 | 519篇 |
1993年 | 345篇 |
1992年 | 374篇 |
1991年 | 343篇 |
1990年 | 288篇 |
1989年 | 262篇 |
1988年 | 173篇 |
1987年 | 188篇 |
1986年 | 141篇 |
1985年 | 96篇 |
1984年 | 55篇 |
1983年 | 39篇 |
1982年 | 38篇 |
1981年 | 27篇 |
1980年 | 27篇 |
1979年 | 16篇 |
1978年 | 6篇 |
1975年 | 7篇 |
1973年 | 10篇 |
1972年 | 6篇 |
排序方式: 共有10000条查询结果,搜索用时 0 毫秒
31.
Effects of smoking and drinking on excretion of hippuric acid among toluene-exposed workers 总被引:1,自引:1,他引:0
Osamu Inoue Kazunori Seiji Takao Watanabe Haruo Nakatsuka Chui Jin Shi-Jie Liu Masayuki Ikeda 《International archives of occupational and environmental health》1993,64(6):425-430
Summary In order to investigate possible effects of smoking and drinking on the metabolism of toluence in occupational settings, 206 toluene-exposed men (mean age: 31.4 years) in shoemaking, painting, or surface-coating workshops together with 246 nonexposed control men (36.8 years) were studied for the time-weighted average intensities of exposure to toluene, hippuric acid concentration in shift-end urine samples, and the two social habits of smoking and drinking. The mean daily consumptions of cigarettes and ethanol were about 20 pieces and 10 g among smokers and drinkers, respectively. The geometric mean toluene concentration among the exposed subjects was about 20 ppm, with a maximum of 521 ppm. Regression analysis after classification of the subjects by smoking and drinking clearly demonstrated that the two social habits, when combined, markedly reduce the hippuric acid level in the urine of workers exposed to was a significant association between smoking and drinking habits, which hindered separate evaluation of the effects of the two habits on toluene metabolism. Comparison of the present results with the findings reported in the literature, however, suggested that the observed effects may be attributable to smoking rather than to drinking habits. 相似文献
32.
中西医结合要为妇女生殖健康创新页 总被引:7,自引:1,他引:6
45年来,复旦大学妇产科医院在中西医结合临床及科研方面取得了可喜的成就.针刺促排卵的研究,通过观察血雌激素和中枢β-内啡肽(β-EP)的关系,提出了针刺通过耗竭中枢β-EP而促排卵的新认识,认为针刺促排卵的主要适应症是青春期月经失调,并将针刺成功地应用于治疗神经性厌食;补肾化痰的俞氏温补方治疗多囊卵巢综合征(polycystic ovary syndrome, PCOS)被证实是通过提高血促卵泡激素(follicle stimulating hormone, FSH)并诱发排卵而起作用;益肾化瘀的天癸方是通过降低患者及动物模型的雄激素和胰岛素,引起以中枢阿片促黑激素皮质素原、神经肽Y和瘦素受体为主的神经-内分泌-代谢网络调节而发挥促排卵和减肥作用,对高胰岛素型PCOS有良效,并在研究中提出了对PCOS分类的新设想;益肾清火的更年春通过提高中枢与周围组织的雌激素受体及其mRNA表达来调节围绝经期妇女的神经-内分泌-免疫-代谢网络而获优越疗效.这些研究表明,疾病是外环境影响下患者生命网络的某些主脉失调所致,而且亚健康状态的妇女具有初步网络失控的现象,中西医结合将为女性生殖医学研究找到捷径,调控生命网络是防病治病的主要思路. 相似文献
33.
原发性肝癌患者肝切除术前、后免疫细胞表型分析 总被引:1,自引:1,他引:0
目的研究原发性肝癌(PrimaryLiverCarcinoma,PLC)患者肝切除术前、后免疫细胞表型的变化。方法采用直接免疫荧光标记,流量血细胞计数法(FlowCytometry,FCM)检测方法,动态观察120例PLC患者肝切除术前后外周血T淋巴细胞亚群、NK细胞和HLA鄄DR含量变化。结果肝切除术前肝功能Child鄄PughB级、OGTTL型和术前施行肝动脉栓塞化疗患者外周血CD8+T细胞含量明显低于正常人组,CD4+/CD8+比值则较高(P<0郾05)。全部肝癌患者肝切除术前、后CD3+CD4+T细胞和NK细胞(CD3-CD16+CD56+)含量无明显差异。术后第1天、第3天、第7天和第2周外周血淋巴细胞CD3+CD8+含量明显低于肝切除术前和术后第3周(P<0.01);而CD4+/CD8+比值则显著高于肝切除术前和术后第3周(P<0郾01)。结论PLC合并肝硬变肝储备功能不足、术前肝动脉栓塞化疗和肝切除术可导致机体细胞免疫功能低下,PLC患者肝切除术前行肝动脉栓塞化疗的价值有待深入研究。 相似文献
34.
Objective To study the protective effects of adenovirus-mediated human beta-nerve growth factor gene (hNGFβ) transfer combined with iron fortified nutrition on blast hearing damage in guinea pigs. Methods Deafness was induced by blast (172dB SPL) in 35 healthy guinea pigs. Seven days after noise exposure, 10 guinea pigs were inoculated with adenovirus-mediated hNGFβ (Ad-hNGFβ) into the perilymphatic space (the gene group), another 10 guinea pigs were given hNGFβ combined with iron fortified nutritional diet (the combination group), still another 10 guinea pigs were inoculated with artificial perilymphatic fluid (APF), and 5 guinea pigs served as control, given neither medicine nor noise exposure. Auditory brainstem response (ABR) threshold shifts were monitored in the guinea pigs before blast exposure and after gene transfer. Changes in cochlear morphology were examined with immunohistochemical and HE staining. Results One week after successful inoculation of hNGFβ, it was noted that Ad-hNGFβ protein was expressed in each turn of the cochlea, and its intensity was almost equal. After gene transfer in the combination group and the gene group, ABR threshold shifts at week 1 and 4 were significantly smaller than those of the APF group. HE staining showed that the number of the spiral ganglion cells in the combination group and the Ad-hNGFβ group was significantly higher than that of the control group after 4 weeks (P<0.01). Conclusions Ad-hNGFβ combined with iron fortified nutritional diet was effective in the prevention and treatment of blast hearing damage of cochlear hair cells. 相似文献
35.
目的:探讨鼻息肉病的可行性手术方法,以提高治疗效果。方法:21例鼻息肉病患者一侧行唇龈沟径路,保留下鼻甲的改良内侧上颌骨切除术(modifiedmedialmaxillectomy,MMM);另侧行单纯鼻息肉摘除和鼻内筛窦切除术,并作为对照组。结果:术后随访12~34个月,平均20个月;改良内侧上颌骨切除术侧未见复发,另侧复发6例,两组复发率差异有显著性(P<0.05)。结论:改良内侧上颌骨切除术使鼻息肉病患者术后复发率显著降低,治疗效果显著,是一种可供选择的有效的治疗手段。 相似文献
36.
尿毒症患者的性激素变化及其临床意义探讨 总被引:6,自引:0,他引:6
目的 :探讨女性尿毒症患者卵巢功能障碍的发病情况及其临床意义。方法 :应用酶免疫法 (EIA)测定了2 3例更年期前女性尿毒症非透析患者、15例透析患者及 2 9例健康献血者中促卵泡素 (FSH)、泌乳素 (PRL)、促黄体素 (LH)、雌二醇 (E2 )及孕酮 (P)的水平。结果 :尿毒症女患者PRL、FSH及LH均较健康对照组升高 ,而孕酮值显著降低 ,对此均有显著差异 ;且尿毒症女患者PRL升高、孕酮值降低与肾小球滤过率 (GFR)呈明显相关。透析患者较非透析患者PRL升高更为明显 ,孕酮值亦较非透析患者有所升高 ,但无显著意义。结论 :尿毒症女患者的排卵障碍及月经紊乱等都与尿毒症的严重程度相平行。透析并不能改善尿毒症女患者的卵巢功能障碍 ,只有纠正与改善肾功能 ,才能使尿毒症女患者的卵巢功能得以改善 相似文献
37.
为探讨临床中使用钙制剂抢救链霉素过敏休克病人有良好效果的原因,由被动血凝试验、被动皮肤过敏试验和ELISA法证实,Ca~( )可以抑制链霉素抗原-抗体的反应。这种抑制作用是通过Ca~( )链霉素抗原结合,封闭链霉素抗原决定簇来加以实现的。 相似文献
38.
Duk Hyun Sung Joon Young Choi Du-Hwan Kim Eun-Sang Kim Young-Ik Son Young-Seok Cho Su Jin Lee Kyung-Han Lee Byung-Tae Kim 《Journal of nuclear medicine》2007,48(11):1790-1795
The purpose of this study was to investigate whether (18)F-FDG PET/CT is useful for localizing dystonic cervical muscles in patients with idiopathic cervical dystonia (ICD) by comparing disease severity before and disease severity after botulinum toxin (BT) injection into hypermetabolic muscles. METHODS: Six patients with ICD underwent (18)F-FDG PET/CT. Dystonic muscles suitable for BT injection therapy were defined as those showing diffusely increased (18)F-FDG uptake. RESULTS: Hypermetabolic cervical muscles were identified in all 6 patients. In 2 patients who underwent PET/CT both in a supine position and in a sitting position during (18)F-FDG uptake, abnormal hypermetabolic muscles were observed by PET/CT only when patients were in the sitting position with their heads and necks in the adopted abnormal involuntary posture. Symptoms were significantly improved in 4 patients who underwent BT injection therapy guided by PET/CT and who were clinically monitored. CONCLUSION: (18)F-FDG PET/CT is potentially useful for identifying dystonic cervical muscles for BT therapy in patients with ICD. 相似文献
39.
1 宋代社会经济、医事制度与历史地理
1.1 宋代的社会经济
宋朝是我国历史上继唐朝之后,社会经济发展、科技文化进步的一个历史时期,后世有"治隆唐宋"之说.公元960年陈桥兵变,赵匡胤(宋太祖)"黄袍加身"以后,遂代周而自立,是为宋朝,史称北宋.当时的社会在经历了五代十国的战乱之后而趋于安定,经济逐渐恢复,科学也日益发达. 相似文献
40.
Kanta Kishi Michiko Muramatsu Denan Jin Keiichi Furubayashi Shinji Takai Hiroshi Tamai Mizuo Miyazaki 《Hypertension research》2007,30(1):77-83
Chymase is known to generate angiotensin II in the vascular wall. In this study we investigated a novel role for chymase other than angiotensin II production in vascular proliferation after balloon injury. Chymase promoted the migration of vascular smooth muscle cells in the matrix-coated invasion chambers and activated promatrix metalloproteinase-2 obtained from the culture medium of vascular smooth muscle cells. Two weeks after balloon injury, significant neointimal formation was found in dog carotid arteries. After injury, active matrix metalloproteinase-2 was increased in parallel with the augmentation of chymase activity that was seen in the proliferating region of the vascular wall. The oral administration of NK3201 (1 mg/kg per day), a chymase inhibitor, prevented neointimal formation and significantly suppressed both active matrix metalloproteinase-2 and chymase activities 2 weeks after injury. These results suggest that chymase inhibitors can prevent the development of intimal hyperplasia via the inhibition of matrix metalloproteinase-2 activation in balloon-injured arteries. 相似文献