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1.
Humans and mammals have sex-specific differences in cardiac electrophysiology, linked to the action of sex hormones in the cardiac muscle. These hormones can upregulate or downregulate the expression of ionic channels modulating the cardiac cycle through genomic and non-genomic interactions. Systematic search in PubMed, Medline and EMBASE including keywords pertaining to testosterone and QT interval. Included experimental studies and observation studies and case reports presenting the results of testosterone administration, excess or deficiency in humans and animals. Testosterone has been shown to shorten the action potential duration, by enhancing the expression of K+ channels and downregulating ICaL increasing the repolarization reserve of the cardiac muscle. This effect has been observed in both genders and animals. Testosterone deficient states can promote arrhythmogenesis. The evidence in this paper may be used to guide clinical considerations, such as increased clinical surveillance of patients in testosterone deficient states using ECG.  相似文献   
2.
血清MUC1粘蛋白IRMA及其初步临床应用   总被引:13,自引:1,他引:12  
建立有效的MUC1粘蛋白免疫放射分析法(IRMA),并初步用于乳腺肿瘤的诊断。利用纯化的MUC1及其多抗,建立MUC1双抗夹心IRMA法,对55例健康女性、11例乳腺良性肿瘤、27例乳腺癌及28例乳腺癌术后患者进行血清MUC1的测定。结果:血清MUC1IRMA的灵敏度为074kU/L;健康女性、乳腺良性肿瘤、乳腺癌及乳腺癌术后患者血清MUC1的平均含量分别为723±367、1780±1056、3004±2384和3184±2479kU/L;正常值上限为1354kU/L,假阳性率为182%;乳腺肿瘤患者血清MUC1水平较健康女性明显提高;乳腺癌患者血清MUC1水平高于乳腺良性肿瘤患者,但两者的阳性率(7787%和7270%)差异无显著性(χ2=0154,P>005);乳腺癌与乳腺癌术后患者血清MUC1水平差异无显著性(t=-022,P>005)。MUC1血清水平与肿瘤恶性程度成正相关,对于乳腺癌的诊断具有重要参考价值。  相似文献   
3.
关节镜下滑膜切除术治疗膝滑膜结核的临床分析   总被引:1,自引:1,他引:0  
目的:探讨关节镜下滑膜切除术治疗膝滑膜结核的疗效。方法:对我院1990年1月至2003年7月的23例膝关节滑膜结核的患者在关节镜下行滑膜切除术并取组织送病理检查。结果:术后经随访16—36个月,患者功能恢复良好,症状消失,优良率达到96.3%。结论:关节镜下滑膜切除术治疗膝关节滑膜结核是一种安全有效的治疗方法。  相似文献   
4.
目的 通过检测健康志愿者的羧酸酯酶1 (carboxylesterase 1,CES1)和羧酸酯酶2 (carboxylesterase 2,CES2)的基因多态性和基因表达水平,探索CES1和CES2在代谢中的作用。方法 从48例健康志愿者获得血样并提取DNA,对DNA进行二代基因测序,并提取总RNA检测基因表达量。使用多元线性回归分析CES1和CES2基因表达量与性别、年龄、体质量指数(body mass index, BMI)的关系。结果 CES1的基因表达量为141.8(72.7,237.8),CES2的基因表达量为74.4(30.8,133.6)。多元线性回归分析中,BMI与CES2的基因表达有关,性别、年龄和BMI与CES1的基因表达无关。发现CES1 20个基因变异,其中10个会引起氨基酸序列改变;发现CES2 6个基因变异,其中2个引起氨基酸序列改变。结论 发现CES2的表达水平与BMI相关,CES1的表达水平与BMI无明显相关,基因预测结果提示CES1的遗传变异可能影响其功能表达。  相似文献   
5.
目的探讨多器官功能障碍综合征(MODS)病程中脾脏树突状细胞(DC)变化对炎症因子的影响与作用。方法采用腹腔注射酵母多糖的方法复制小鼠MODS模型,分为正常对照组和MODS组。采用流式细胞技术检测脾脏DC免疫表型,运用免疫组化技术检测脾脏中促炎因子IL-1β与抗炎因子IL-10的表达,计量观察DC与炎症因子在病程中的变化并做相关分析。结果伤后6h组,脾脏中CD11c^+/MHC-Ⅱ’DC数目与IL-18’细胞数目均明显增多,至24h组达峰值。自48h组,CD11c^+/MHC-Ⅱ’DC与IL-1β’细胞含量开始下降,在6天组和10~12天组降至正常组或低于正常组含量;而同时CD11c^+/MHC-Ⅱ^-DC和IL-10阳性细胞含量则相对增多,至10~12天组阳性细胞含量显著升高达到峰值。结论DC的活性在MODS病程早期与IL-1β表达呈正相关性,在病程晚期与IL-10表达呈负相关,提示脾脏DC活性变化与促炎因子和抗炎因子均有密切的相关性。  相似文献   
6.
《Injury》2021,52(2):281-285
IntroductionAccidental falls are the most common causes of injury among infants. Due to their limited ability to move independently, falling from bed or other types of furniture (such as sofas or armchairs) is considered the most common reason for such injury. However, little is known about the frequency and types of injury associated with this type of fall among infants. This study aimed to determine the incidence and characteristics of injury among infants presented at emergency departments (ED) after falling from bed or similar furniture.MethodsThe retrospective analysis of infants under one year old presenting at ED after falling from bed (or similar furniture) was performed over a four-year period (2016–2019). Patient demographics, incidence and patterns of injury, outcomes, and ED resources use were evaluated as part of the study.ResultsIn total, 1,439 infants were included in the study, of whom 782 (54.3%) were male and 657 (45.7%) female. The median age of the patients was 7 months (interquartile range [IQR]: 6–9 months). More than half the infants (n = 812, 56.4%) had minor injuries, such as abrasions, bruising, contusions, and lacerations. There were significant injuries for 135 (9.4%) infants. The most common fracture was skull fracture (n = 59, 4.1%), followed by proximal fracture of the upper extremities (n = 26, 1.8%). Six (0.4%) patients had radial head subluxation. Traumatic brain injury featured for 30 (2.1%) infants (intracranial hemorrhage/cerebral contusion). While the majority of patients (n = 1352, 94%) were discharged from ED, 86 (6%) infants were hospitalized, all due to head injuries. A neurosurgical intervention was performed with three (0.2% of all patients) of the hospitalized patients.ConclusionFalling from bed causes skull fractures, traumatic brain injury, and long bone fractures among infants. Therefore, campaigns should be organized to raise awareness of these risks among parents and caregivers of infants. In addition, the use of safety equipment (such as bed rails) and creating a safe environment can help prevent significant injuries.  相似文献   
7.
Background ContextPrevious studies have reported conflicting results for the relationships between anthropometric adiposity indexes and bone mineral density, based on dual-energy X-ray absorptiometry (DXA). However, few studies were published based on quantitative computed tomography (QCT), especially for Chinese population.PurposeTo evaluate the associations of spine bone mineral density (BMD) with body mass index (BMI), waist circumstance (WC), waist-to-hip ratio (WHR), waist-to-height ratio (WHtR) and a body shape index (ABSI) using QCT.Study Design/SettingA Cross-sectional study.Patient SampleAround 3,457 participants in multiple communities across 7 administrative regions of China.Outcome MeasuresSpine BMD was measured using QCT, and the classification of osteoporosis was defined as follows: 1) osteoporosis if BMD <80mg/cm3, 2) osteopenia if BMD 80–119 mg/cm3, and 3) normal bone mass if BMD≥120 mg/cm3.MethodsThis study was conducted using convenient sampling between 2013 and 2017. Multivariable linear regression model and logistic regression models were used for the associations of continuous and categorical BMD, respectively.ResultsAround 3,405 participants were included in the final analyses, including 1,272 males and 2,133 females, with spine BMD of 111.00±35.47 mg/cm3 and 99.38±40.60 mg/cm3, respectively. Spine BMD decreased significantly with the increase of ABSI in females (adjusted β, ?5.74; 95% confidence interval [CI], ?8.50 to ?2.98), and this trend also was kept in females aged at less than 60 years (adjusted β, ?14.54; 95% CI, ?20.40 to ?8.68), and females with age ≥60 years (adjusted β, ?7.59; 95% CI, ?10.91 to ?4.28). However, this inverse association was observed only in males with age ≥ 60 years (adjusted β, ?5.19; 95% CI, ?10.08 to ?0.29). Except ABSI, negative associations of Spine BMD with WC (adjusted β, ?0.46; 95% CI, ?0.77 to ?0.15), WHR (adjusted β, ?6.25; 95% CI, ?10.63 to ?1.86), WHtR (adjusted β, ?6.80; 95% CI, ?11.63 to ?1.97) were shown in females aged at <60 years, and positive association with BMI in males with age ≥60 years (adjusted β, 0.92; 95% CI, 0.29–1.55).ConclusionsABSI had more remarkable association with spine BMD, compared with the other four indexes.  相似文献   
8.
The goal of cancer immunotherapy is to clear tumor cells by activating antitumor immunity, especially by mobilizing tumor-reactive CD8+T cells. Pyroptosis, programmed lytic cell death mediated by gasdermin (GSDM), results in the release of cellular antigens, damage-associated molecular patterns (DAMPs) and cytokines. Therefore, pyroptotic tumor cell-derived tumor antigens and DAMPs not only reverse immunosuppression of the tumor microenvironment (TME) but also enhance tumor antigen presentation by dendritic cells, leading to robust antitumor immunity. Exploring nanoparticles and other approaches to spatiotemporally control tumor pyroptosis by regulating gasdermin expression and activation is promising for next-generation immunotherapy.  相似文献   
9.
10.
目的 从临床常用药物中探寻逆转肿瘤耐药性的活性物质。方法 应用MTT法测定不同浓度Hal处理的瘤细胞对 0~ 2 0 μmol·L- 1多柔比星 (Dox)的敏感性的影响。RT PCR法分析 12 .5 μmol·L- 1氟哌啶醇 (Hal)处理后多药耐药基因 (MDR1) ,多药耐药相关蛋白 (MRP)和谷胱甘肽S转移酶Pi(GSTπ)mRNA表达的变化。通过流式细胞术观察 0 ,6 .2 5 ,12 .5 ,2 5 μmol·L- 1Hal对细胞内药物蓄积和细胞周期进程的影响。结果 Hal对K5 6 2 /Dox的耐药性具有明显的逆转作用。在 12 .5 ,6 .2 5及 3.12 5 μmol·L- 1时的逆转倍数分别为 8.35 ,4 .2 1及 2 .16。用 12 .5μmol·L- 1Hal处理后 ,MDR1及MRP的mRNA表达水平均呈现时间依赖性明显降低 ,分别较原水平下降76 .3%及 6 4.6 %。药后d 2GSTπmRNA表达下降6 6 .1% ,于d 3回升。Hal处理细胞lh后 ,Dox在细胞内蓄积量明显增加 ,并呈浓度依赖性 ;此外 ,Hal可明显增强Dox对K5 6 2 /Dox细胞的G2 /M阻滞作用 ,12 .5 μmol·L- 1浓度可以使 5 μmol·L- 1Dox的G2 /M阻断由单独应用时的 9.9%± 4 .3%增加到2 3.4 %± 3.0 %。结论 Hal具有较强的逆转K5 6 2 /Dox细胞MDR的作用 ,其逆转机制为多种途径 ,包括相关基因mRNA的表达下调 ,增加细胞内药物蓄积 ,增强Dox对K5 6 2 /Dox在G2  相似文献   
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