全文获取类型
收费全文 | 17184篇 |
免费 | 1107篇 |
国内免费 | 1015篇 |
专业分类
耳鼻咽喉 | 62篇 |
儿科学 | 377篇 |
妇产科学 | 583篇 |
基础医学 | 664篇 |
口腔科学 | 329篇 |
临床医学 | 2368篇 |
内科学 | 5046篇 |
皮肤病学 | 74篇 |
神经病学 | 204篇 |
特种医学 | 696篇 |
外国民族医学 | 1篇 |
外科学 | 2210篇 |
综合类 | 2474篇 |
预防医学 | 926篇 |
眼科学 | 14篇 |
药学 | 1624篇 |
33篇 | |
中国医学 | 783篇 |
肿瘤学 | 838篇 |
出版年
2024年 | 36篇 |
2023年 | 375篇 |
2022年 | 644篇 |
2021年 | 879篇 |
2020年 | 773篇 |
2019年 | 656篇 |
2018年 | 612篇 |
2017年 | 610篇 |
2016年 | 668篇 |
2015年 | 621篇 |
2014年 | 1340篇 |
2013年 | 1434篇 |
2012年 | 1142篇 |
2011年 | 1233篇 |
2010年 | 985篇 |
2009年 | 856篇 |
2008年 | 861篇 |
2007年 | 872篇 |
2006年 | 749篇 |
2005年 | 624篇 |
2004年 | 459篇 |
2003年 | 382篇 |
2002年 | 318篇 |
2001年 | 284篇 |
2000年 | 242篇 |
1999年 | 192篇 |
1998年 | 146篇 |
1997年 | 151篇 |
1996年 | 117篇 |
1995年 | 107篇 |
1994年 | 108篇 |
1993年 | 80篇 |
1992年 | 80篇 |
1991年 | 63篇 |
1990年 | 83篇 |
1989年 | 60篇 |
1988年 | 51篇 |
1987年 | 32篇 |
1986年 | 42篇 |
1985年 | 46篇 |
1984年 | 45篇 |
1983年 | 27篇 |
1982年 | 52篇 |
1981年 | 34篇 |
1980年 | 32篇 |
1979年 | 21篇 |
1978年 | 27篇 |
1977年 | 24篇 |
1976年 | 11篇 |
1973年 | 8篇 |
排序方式: 共有10000条查询结果,搜索用时 0 毫秒
41.
Anne M. Weber MD Allison R. Mitchinson MPH Gita P. Gidwani MD Edward Mascha MS Mark D. Walters MD 《American journal of obstetrics and gynecology》1997,176(6):1213-1219
OBJECTIVE: Our purpose was to describe clinical characteristics in premenopausal women with uterine myomas and to identify factors associated with hysterectomy.STUDY DESIGN: Data were collected by chart abstraction in 421 premenopausal women with myomas and analyzed by univariate and multivariable regression.RESULTS: Over a median follow-up period of 29 months, 86% of women had symptoms associated with myomas and 40% had an increase in uterine size of >2 gestational weeks. By multivariable regression, bleeding symptoms at presentation and previous surgical history of cholecystectomy and adhesiolysis were significantly associated with greater odds of hysterectomy. There was a significant interaction between age and uterine size, so that as age increased, uterine size had a greater impact on the likelihood of hysterectomy.CONCLUSIONS: In this cohort of premenopausal women myomas were associated with symptoms in almost all women over the follow-up period. Hysterectomy was performed in 22% of women overall. (Am J Obstet Gynecol 1997;176:1213-9.) 相似文献
42.
新生儿胃肌电变化的研究 总被引:2,自引:0,他引:2
目的 观察新生儿胃肌电发育过程,并初步探讨其变化规律。方法 对23例健康新生儿生后1周、2周及1月进行胃肌电描记。采用皮肤表面电极,从腹壁体表用PCPOLYGRAP-HR多功能胃肠检测仪记录胃电,观察主频率(DF)、主频率不稳定系数(DFIC)、正常胃慢波百分比(PNSW)。结果 餐前、餐后正常呈随周龄增大而增加的趋势,餐后PNSW明显高于餐前。DF和DFIC各阶段无明显差异,但自身比较,餐后DF高于餐前,餐后DFIC低于餐前。结论 研究显示出新生儿胃电肌运动的发育过程。 相似文献
43.
平滑肌是胃肠运动的基础,其收缩和舒张涉及电-机械偶联和药物-机械偶联。其中有钙离子和其他信号分子的参与。本文通过电生理特性,钙和钙动员,收缩装置和途径,信号转导途径和交叉对话来总结信号转导在胃肠平滑肌中的作用。 相似文献
44.
目的探讨微小剂量肝素降低新生儿重度窒息并发全身炎症反应综合征(SIRS)的作用和机制,并观察其副作用。方法对我科2001年1月~2005年10月间94例重度窒息新生儿(不含新生早产儿窒息病例)作回顾性分析。治疗组48例,常规综合治疗基础上加用低分子肝素钠5U/(kg·次),皮下注射,每12h1次,连用3d。对照组46例,采用综合治疗。就组间1周内SIRS的发生率作对照分析。结果治疗组1周内SIRS发生率和对照组间存在比较显著差异(P<0.05〉,而新生儿颅内出血、上消化道出血、和皮下出血的发生情况比较无显著差异性(P均>0.05)。结论早期应用微小剂量肝素可有效降低重度窒息新生儿SIRS的发生率而不致增加继发器官出血的机会。 相似文献
45.
Yao Lin Yiming Shao Yuchun Liu Ruoxuan Yang Shuanglin Liao Shuai Yang Mingwei Xu Junbing He 《Renal failure》2022,44(1):1263
BackgroundNafamostat mesilate (NM), a broad-spectrum and potent serine protease inhibitor, can be used as an anticoagulant during extracorporeal circulation, as well as a promising drug effective against coronavirus disease 2019 (COVID-19). We conducted a systematic meta-analysis to evaluate the safety and efficacy of NM administration in critically ill patients who underwent blood purification therapy (BPT).MethodsThe Cochrane Library, Web of Science and PubMed were comprehensively searched from inception to August 20, 2021, for potential studies.ResultsFour randomized controlled trials (RCTs) and seven observational studies with 2723 patients met the inclusion criteria. The meta-analysis demonstrated that conventional therapy (CT) significantly increased hospital mortality compared with NM administration (RR = 1.25, p = 0.0007). In subgroup analyses, the in-hospital mortality of the NM group was significantly lower than that of the anticoagulant-free (NA) group (RR = 1.31, p = 0.002). The CT interventions markedly elevated the risk ratio of bleeding complications by 45% (RR = 1.45, p = 0.010) compared with NM interventions. In another subgroup analysis, NM used exhibited a significantly lower risk of bleeding complications than those of the low-molecular-weight heparin (LMWH) used (RR = 4.58, p = 0.020). The filter lifespan was decreased significantly (MD = −10.59, p < 0.0001) in the NA groups compared with the NM groups. Due to the poor quality of the included RCTs, these results should be interpreted with caution.ConclusionGiven the better survival outcomes, lower risk of bleeding, NM anticoagulation seems to be a safe and efficient approach for BPT patients and could yield a favorable filter lifespan. More multi-center RCTs with large samples are required for further validation of this study. 相似文献
46.
胃肠道间质瘤21例临床分析 总被引:2,自引:2,他引:0
目的:探讨胃肠道间质瘤(GIST)的诊断和治疗方法。方法:收集21例GIST临床资料,进行回顾性分析。结果:21例平均年龄56.2岁,主要临床表现为腹部胀痛、腹部包块、黑便及贫血,2例无任何不适于查体时发现。9例经超声内镜检查确诊。21例均行根治性手术,肿瘤位于胃14例,小肠5例,肠系膜2例。21例均经术后病理检查及免疫组化确诊GIST,免疫组化表型以CD117、CD34阳性率较高。根据Miettinen等原则分类,良性5例,低度恶性10例,中等度恶性3例,高度恶性3例。结论:GIST的术前诊断有赖于纤维内镜、超声内镜、B超、CT等检查的综合应用,病理检查及免疫组化表型分析是确诊金标准,手术切除是最有效的治疗手段。 相似文献
47.
Na Ri Choi Jeong Nam Kim Min Ji Kwon Jong Rok Lee Sang Chan Kim Min Jae Lee Woo-gyun Choi Byung Joo Kim 《International journal of medical sciences》2022,19(5):941
Grape seed is an important natural bioactive product with various health benefits. Interstitial cells of Cajal (ICCs) are pacemaker cells in the gastrointestinal (GI) tract. The present study investigated the effects of grape seed powder (GSP) on ICC properties and GI motility. GSP depolarized the pacemaker potentials of ICCs in a dose‑dependent manner. Y25130 or SB269970 slightly inhibited GSP‑induced effects. However, Y25130 and SB269970 together completely blocked GSP-induced effects. In the presence of inhibitors of protein kinase C, protein kinase A, or mitogen-activated protein kinase, GSP‑induced ICC depolarization was inhibited. GSP increased the intestinal transit rate in normal mice and in mice with acetic acid-induced GI motility disorder. In addition, the levels of motilin and substance P were elevated after GSP dosing. These results demonstrate that GSP can regulate GI motility, and therefore, it is a potential therapeutic agent for treating GI motility disorders. 相似文献
48.
目的:观察奥曲肽治疗肝硬化门静脉高压食管胃底静脉曲张出血肝静脉压力梯度(HVPG)等的变化,探讨奥曲肽止血机制.方法:采用随机对照的方法,病例分为低剂量奥曲肽治疗组(A组,n=18);高剂量奥曲肽治疗组(B组,n=18)和对照组(C组,n =18).治疗肝硬化食管胃底静脉曲张出血,在基础治疗(禁食、输液、输血、对症处理)的基础上,全部病例予以奥美拉唑注射液40 mg,每12h1次静脉滴注抑酸.治疗组A、B组分别以奥曲肽注射液25、50 μg/h的速度微泵静脉维持治疗.观察治疗前后HVPG,门静脉内径,血流速度及呕血、黑便等的改变情况.结果:治疗前与治疗后24、72 h,两治疗组HVPG比较对照组显著降低,有统计学差异(P =0.00,P=0.00).而治疗组A、B治疗后24 h HVPG有统计学差异(P=0.00),治疗后72 h HVPG无统计学差异(P=0.14).治疗组比较对照组门静脉内径减小有统计学差异(P<0.05);治疗组A、B与对照组在治疗24、72 h呕血,黑便量相比较明显减少,有统计学差异(P<0.05).结论:奥曲肽能显著降低HVPG,减少门静脉内径,较高浓度奥曲肽在24 h内疗效更快,奥曲肽联合奥美拉唑比较单独奥美拉唑止血疗效更显著. 相似文献
49.
目的:观察止崩汤加针灸治疗围绝经期功能失调性子宫出血(功血)大出血的疗效及探讨止血机理。方法:将320例围绝经期功血大出血患者口服止崩汤加针灸观察止血疗效、治疗前后临床症状改善情况、子宫内膜厚度、APTT、PT、血色素(HB)、血清雌二醇(E2)、孕酮(P)的含量。结果:(1)止崩汤加针灸治疗功血大出血止血疗效总有效率为91.3%.(2)治疗后APTT时间明显延长(P≤0.05),PT时间明显缩短(P≤0.05)。(3)子宫内膜的厚度变薄,治疗后与治疗前比较有显著性差异(P0.05);(4)治疗后E2含量明显下降(P0.01),P含量则明显上升(0.01),与治疗前比较有极显著性差异(P0.01)。(5)治疗后血色素明显提高。结论:止崩汤加针灸治疗围绝经期功血大出血具有良好的止血作用,起到药物性刮宫的作用,止血迅速快捷便利,无手术刮宫的疼痛及创伤,可调节卵巢激素。 相似文献
50.
Pharmacological effects of green tea on the gastrointestinal system 总被引:11,自引:0,他引:11
Green tea is rich in polyphenolic compounds, with catechins as its major component. Studies have shown that catechins possess diverse pharmacological properties that include anti-oxidative, anti-inflammatory, anti-carcinogenic, anti-arteriosclerotic and anti-bacterial effects. In the gastrointestinal tract, green tea was found to activate intracellular antioxidants, inhibit procarcinogen formation, suppress angiogenesis and cancer cell proliferation. Studies on the preventive effect of green tea in esophageal cancer have produced inconsistent results; however, inverse relationships of tea consumption with cancers of the stomach and colon have been widely reported. Green tea is effective to prevent dental caries and reduce cholesterols and lipids absorption in the gastrointestinal tract, thus benefits subjects with cardiovascular disorders. As tea catechins are well absorbed in the gastrointestinal tract and they interact synergistically in their disease-modifying actions, thus drinking unfractionated green tea is the most simple and beneficial way to prevent gastrointestinal disorders. 相似文献