全文获取类型
收费全文 | 6501篇 |
免费 | 370篇 |
国内免费 | 213篇 |
专业分类
耳鼻咽喉 | 194篇 |
儿科学 | 128篇 |
妇产科学 | 17篇 |
基础医学 | 570篇 |
口腔科学 | 21篇 |
临床医学 | 519篇 |
内科学 | 2127篇 |
皮肤病学 | 22篇 |
神经病学 | 145篇 |
特种医学 | 188篇 |
外科学 | 675篇 |
综合类 | 1173篇 |
现状与发展 | 1篇 |
预防医学 | 128篇 |
眼科学 | 26篇 |
药学 | 887篇 |
1篇 | |
中国医学 | 230篇 |
肿瘤学 | 32篇 |
出版年
2023年 | 51篇 |
2022年 | 74篇 |
2021年 | 164篇 |
2020年 | 151篇 |
2019年 | 128篇 |
2018年 | 127篇 |
2017年 | 108篇 |
2016年 | 114篇 |
2015年 | 171篇 |
2014年 | 305篇 |
2013年 | 426篇 |
2012年 | 298篇 |
2011年 | 327篇 |
2010年 | 344篇 |
2009年 | 291篇 |
2008年 | 348篇 |
2007年 | 362篇 |
2006年 | 344篇 |
2005年 | 305篇 |
2004年 | 281篇 |
2003年 | 273篇 |
2002年 | 228篇 |
2001年 | 240篇 |
2000年 | 186篇 |
1999年 | 201篇 |
1998年 | 164篇 |
1997年 | 136篇 |
1996年 | 131篇 |
1995年 | 99篇 |
1994年 | 92篇 |
1993年 | 65篇 |
1992年 | 58篇 |
1991年 | 61篇 |
1990年 | 43篇 |
1989年 | 43篇 |
1988年 | 28篇 |
1987年 | 31篇 |
1986年 | 24篇 |
1985年 | 41篇 |
1984年 | 38篇 |
1983年 | 23篇 |
1982年 | 26篇 |
1981年 | 15篇 |
1980年 | 18篇 |
1979年 | 20篇 |
1978年 | 17篇 |
1977年 | 15篇 |
1976年 | 18篇 |
1975年 | 11篇 |
1973年 | 8篇 |
排序方式: 共有7084条查询结果,搜索用时 78 毫秒
81.
女性单纯声带肥厚和声带小结的嗓音参数分析比较 总被引:2,自引:0,他引:2
目的:通过比较和分析单纯声带肥厚和声带小结的嗓音参数的变化,评价这些参数在两种疾病中诊断及疗效。方法:应用Dr.Speech(DSS)软件对成人女性30例单纯声带肥厚和声带小结患者做噪音测试,对其主要声学参数进行比较分析。结果:声带小结的嗓音声学参数、基频微扰、声门噪声能量NEE值均较声厚的各指标高。其中声门噪声能量在声结中异常者占99.6%,声带肥厚占80%,两组之间有显著性差异(P<0.05)。其频微扰和振幅微扰的异常占有率,两组之间无显著性差异(P>0.05)。结论:嗓音参数对诊断和区别声带肥厚和声结有一定的价值,特别是声门噪声能量有更高的敏感性,对诊断和治疗声带疾病有一定的价值。 相似文献
82.
目的 :评价氯沙坦、福辛普利、氨氯地平对自发性高血压大鼠 (SHR)心肌细胞凋亡及左室重构的效应。方法 :将 40只 16周龄SHR随机分为氯沙坦治疗组 (SHR -L)、福辛普利治疗组 (SHR -F)、氨氯地平治疗组 (SHR -A)及空白对照组 (SHR -C)。采用末端脱氧核糖核苷酸转移酶介导dUTP缺口末端标记、放免及病理检查方法对SHR治疗 8周、16周心肌细胞凋亡指数 (APOI)、血浆和组织血管紧张素II(PAngII,MAngII)及左室重构指标检测。结果 :①各治疗组治疗 8周、16周收缩压均明显下降 ,组间差异无显著性 ;各治疗组左室重量 (LVW)、左室重量指数 (LVMI)均有显著性改善 ,SHR -F组治疗 16周较其他两组LVMI显著减低。②仅SHR -F组治疗 8周APOI显著性下降 ,治疗 16周各治疗组APOI均有显著下降 ,尤以SHR -F组下降明显。③SHR -L组治疗 8周及 16周PAngII,MAngII显著增加。SHR -F组治疗 8周MAngII显著下降 ,治疗 16周SHR -F ,SHR -A两组MAngII均明显下降 ,且前组较后组下降显著 ,但对PAngII无明显影响。结论 :3药物均能有效逆转心脏肥厚及抗心肌细胞凋亡 ,其中以福辛普利显著。上述作用可能是拮抗心肌组织肾素 -血管紧张素 -醛固酮系统的效应。 相似文献
83.
84.
Riccardo Memeo Maria Conticchio Emmanuel Deshayes Silvio Nadalin Astrid Herrero Boris Guiu Fabrizio Panaro 《肝胆外科与营养》2021,10(3):350
Liver resection still represent the treatment of choice for liver malignancies, but in some cases inadequate future remnant liver (FRL) can lead to post hepatectomy liver failure (PHLF) that still represents the most common cause of death after hepatectomy. Several strategies in recent era have been developed in order to generate a compensatory hypertrophy of the FRL, reducing the risk of post hepatectomy liver failure. Portal vein embolization, portal vein ligation, and ALLPS are the most popular techniques historically adopted up to now. The liver venous deprivation and the radio-embolization are the most recent promising techniques. Despite even more precise tools to calculate the relationship among volume and function, such as scintigraphy with 99mTc-mebrofenin (HBS), no consensus is still available to define which of the above mentioned augmentation strategy is more adequate in terms of kind of surgery, complexity of the pathology and quality of liver parenchyma. The aim of this article is to analyse these different strategies to achieve sufficient FRL. 相似文献
85.
A. Bass J. Teisinger P. Hnik E. V. Macková R. Vejsada I. Eržen 《Pflügers Archiv : European journal of physiology》1984,400(2):188-193
Muscle hypertrophy was induced in the soleus muscle of young rats by tenotomy of the gastrocnemius and plantaris muscles. Three and 7 days afterwards the sciatic nerve was sectioned. The loss of weight of muscles subjected to this combined procedure three days after denervation was 30–40%. Lysosomal enzyme activities (acid phosphatase, -glucosidase, -galactosidase and N-acetyl--d-glucosaminidase) and energy enzyme activities (lactate dehydrogenase, LDH, triose-3-phosphate dehydrogenase, TPDH,d-hexokinase, HK and citrate synthase, CS) were determined 3 days after denervation, 3, 7 and 10 days after hypertrophy had been induced and 3 days after denervation of hypertrophying muscles on day 3 and 7. Normal non-operated rats of corresponding body wieght served as controls and their enzyme activities were estimated on the same day. In the course of muscle hypertrophy, the 4 lysosomal enzyme activities increased progressively. Although 3 days' denervation of control muscles did not alter lysomal enzyme activities, denervation of hypertrophying muscles greatly enhanced the activity of these enzymes. Enzymes of energy metabolism were affected to a lesser degree. The results suggest that denervation of hypertrophying muscles causes more extreme changes in muscle weight and lysosomal enzyme activities than denervation alone. The possible implications of this finding are discussed in relation to the rapid atrophy. 相似文献
86.
Upper gastrointestinal contrast studies were carried out on 24 patients at progressive time intervals following gastric partition
with partial biliopancreatic bypass (modified Scopinaro procedure) for morbid obesity. Roentgenograms taken on standardized
equipment were compared in order to document adaptive changes occurring in the small bowel with time following the procedure.
Mucosal fold thickness and bowel lumen calibre within the terminal ileum were found to increase significantly with (log) time.
Such adaptation of the ileum is well recognized following jejunoileal bypass, but radiological demonstration after biliopancreatic
bypass has not been described previously. Mucosal hypertrophy and increase in bowel lumen calibre should be recognized as
normal adaptive changes in the small bowel and not be misinterpreted as evidence of underlying pathology. Whilst adaptation
following jejunoileal bypass undoubtedly contributes to eventual weight gain following surgery, this detrimental effect following
the modified Scopinaro procedure appears to be negated by the reduced intake and maldigestion imposed by this procedure. 相似文献
87.
目的:探讨依即普利对高血压左室肥厚与左室舒张功能的治疗作用。方法:对符合WHO诊断标准的原发性高血压左室肥厚,服用依那普 治疗,用彩色普勒超声心电图测定治疗前后左室肥厚、左室收缩及舒张功能指标。结果:治疗后室间隔厚度、左室后壁厚度、左室心肌重量均明显减少,舒张早期流速峰值明显增大,房缩期最大流速下降,两比值下降,左室射血分数无变化。结论:依那普利可有效地抑制并逆转左室肥厚,改善左室舒张功能。 相似文献
88.
目的 探讨良性前列腺增生症 (BPH)血清前列腺特异性抗原 (PSA)的临床特点。方法 回顾性分析 111例住院待术和 45 7例普查中诊断的BPH的PSA、PSAD情况。结果 手术组和普查组的PSA和PSAD值分别为 6 .5 8± 7.49ng/ml、0 .12± 0 .15和 3.77± 4.6 0ng/ml、0 .9± 0 .11。普查组的PSA值与患者年龄呈显著正相关 (P <0 .0 1) ,而手术组无明显相关性 (P >0 .0 5 )。留置导尿的BPH其PSA(7.6 9± 8.0 5ng/ml,P <0 .0 1)和PSAD(0 .13± 0 .17,P <0 .0 1)显著高于非留置导尿者。而直肠指检触及前列腺表面结节者其PSA值 (6 .72± 5 .81ng/ml)也明显高于无结节的患者 (P <0 .0 1)。结论 BPH患者血清PSA个体差异较大 ,留置导尿及前列腺结节均可能引起PSA升高 ,在临床评估中需予综合考虑。 相似文献
89.
Exogenous insulin-like growth factor II enhances post-infarction regional myocardial function in swine 总被引:1,自引:0,他引:1
BATTLER A.; HASDAI D.; GOLDBERG I.; OHAD D.; DI SEGNI E.; BOR A.; VARDA-BLOOM N.; VERED Z.; KORNOWSKI R.; LAKE M.; NASS D.; SAVION N. 《European heart journal》1995,16(12):1851-1859
OBJECTIVES: Insulin-like growth factor II (IGF-II) promotes cardiac myocytegrowth and contractility in vitro. This study was designed toinvestigate the effect of exogenous IGF-II on regional myocardialfun ction at the area of infarct in the pig. METHODS: Myocardial infarction was induced in 12 female anoesthetizedpigs by affigel blue beads, embolizing microvessels of the leftanterior descending coronary artery distribution. In the experimentalgroup (n=6), IGF-II (0.12 µg. kg1 in two animalsand 0.6 µg. kg1 in four) was incorporated intothe beads and delivered by them to the infarct area. Myocardialfunction was followed echocardiographically, and the excisedheart was analysed immunohistochemically and histopathologically. RESULTS: Myocardial function in injured zones, inversely related to anechocardiographic segmental wall motion score (mean ±SEM), was similar between the two groups at baseline, but at4 weeks post-infarction was significantly (P=0.008) reducedin the control group (0.58± 0.38 vs 3.42 ± 0.84),in contrast to nearly baseline values in the experimental group(0.58 ± 0.33 vs 1.17 ± 0.42, P=0.41). Cardiacperformance in injured segments was sign better after myocardialinjury in the experimental group (P=0.04). Tissue samples fromboth groups (4 weeks post-infarction), stained with haematoxylinand eosin demonstrated pen-infarct myocyte hypertrophy, correspondingto regions selectively stained by an antibody for CD56, whichhighlights growing cardiac myocytes. By image analysis semi-quantification,staining for CD56 was significantly (P=0.04) higher in the peri-infarctregion of the experimental group, as compared with controls(106.5 ± 2.8 vs 92 ± 4.4 gray level units). Microvesselsstained for von-Willebrand factor were similar in nwnber inboth groups (P=0.8), as were mesenchymal cells stained for vimentin(P=0.7). CONCLUSIONS: Exogenous IGF-II, delivered to the infarct area amelioratesregional cardiac function in the pig, perhaps by inducing peri-infarctmyocyte growth. 相似文献
90.
目的 探讨高血压病左心室肥厚及左心房增大与室性心律失常的关系。方法 采用24小时动态心电图及超声心动图测定68例高血压病患者心律失常及心脏结构的变化。结果 左心室肥厚组室性心律失常发生率显著高于非左心室肥厚组(P相似文献