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101.
IL Ackerman  CA Karn  SC Denne  GJ Ensing  CA Leitch 《Pediatrics》1998,102(5):1172-1177
OBJECTIVE: The purpose of this study was to determine the effect of left-to-right shunting on the resting energy expenditure (REE), total energy expenditure (TEE), and energy intake in a group of 3- to 5-month-old infants with moderate to large unrepaired ventricular septal defects (VSDs) compared with age-matched, healthy infants. METHODS: Eight infants with VSDs and 10 healthy controls between 3 to 5 months of age participated in the study. Indirect calorimetry was used to measure REE and the doubly-labeled water method was used to measure TEE and energy intake. An echocardiogram and anthropometric measurements were performed on all study participants. Daily urine samples were collected at home for 7 days. Samples were analyzed by isotope ratio mass spectrometry. Data were compared using analysis of variance. RESULTS: No significant differences were found in REE (VSD, 42.2 +/- 8.7 kcal/kg/d; control, 43.9 +/- 14.1 kcal/kg/d) or energy intake (VSD, 90.8 +/- 19.9 kcal/kg/d; control, 87.1 +/- 11.7 kcal/kg/d) between the groups. The percent total body water was significantly higher in the VSD infants and the percent fat mass was significantly lower. TEE was 40% higher in the VSD group (VSD, 87.6 +/- 10.8 kcal/kg/d; control, 61.9 +/- 10.3 kcal/kg/d). The difference between TEE and REE, reflecting the energy of activity, was 2.5 times greater in the VSD group. CONCLUSIONS: REE and energy intake are virtually identical between the two groups. Despite this, infants with VSDs have substantially higher TEE than age-matched healthy infants. The large difference between TEE and REE in VSD infants suggests a substantially elevated energy cost of physical activity in these infants. These results demonstrate that, although infants with VSDs may match the energy intake of healthy infants, they are unable to meet their increased energy demands, resulting in growth retardation.  相似文献   
102.
Functional MRI (fMRI) was used to assess proprioceptive‐associated cervical cord activity in 24 relapsing multiple sclerosis (MS) patients and 10 controls. Cord and brain conventional and diffusion tensor (DT) MRI were also acquired. fMRI was performed using a block design during a proprioceptive stimulation consisting of a passive flexion‐extension of the right upper limb. Cord lesion number, cross‐sectional area, mean diffusivity (MD) and fractional anisotropy (FA), whole brain and left corticospinal tract lesion volume (LV), gray matter (GM) MD, and normal‐appearing white matter (NAWM) MD and FA were calculated. MS patients had higher average cord fMRI signal changes than controls (3.4% vs. 2.7%, P = 0.03). Compared to controls, MS patients also had a higher average signal change in the anterior section of the right cord at C5 (P = 0.005) and left cord at C5–C6 (P = 0.03), whereas no difference was found in the other cord sections. Cord average signal change correlated significantly with cord FA and brain left corticospinal tract LV, GM‐MD, and NAWM‐FA. This study shows an abnormal pattern of activations in the cervical cord of MS patients following proprioceptive stimulation. Cord fMRI changes might have a role in limiting the clinical consequences of MS associated with irreversible tissue damage. Magn Reson Med 59:1035–1042, 2008. © 2008 Wiley‐Liss, Inc.  相似文献   
103.
中西医结合治疗老年高脂血症   总被引:2,自引:1,他引:2  
目的:探讨中西医结合治疗高脂血症的临床疗效。方法:符合高脂血症标准的老年患者120例,随机分为A、B2组各60例,A组采用益肾化淤、利湿化浊为主的中药及西药辛伐他汀片治疗;B组则单纯用辛伐他汀片治疗。治疗前及治疗4周后2组均行全套血脂水平测定。结果:与B组比较,A组血清总胆固醇(TC)及甘油三酯(TG)均明显下降,HDL明显上升(均P〈0.05);A组临床控制率明显高于B组(P〈0.05);治疗后A组患者未见肝功能损害,B组转氨酶及转肽酶轻度异常,2例。停药3个月后,A组复发率低于B组(2.2%、8.8%,P〈0.05)。结论:中西医结合治疗老年高脂血症的临床效果明显优于单一的一种治疗方法,值得临床进一步推广应用。  相似文献   
104.

Introduction

TobraDex® ophthalmic suspension (tobramycin 0.3%, dexamethasone 0.1%; Alcon Laboratories Inc, Fort Worth, Tex) is frequently used for inflammatory ocular conditions where a risk of bacterial ocular infection exists. A new formulation, TobraDex® ST ophthalmic suspension (tobramycin 0.3%, dexamethasone 0.05%, Alcon), utilises a novel suspension technology to reduce viscosity and help prevent settling in the container.

Methods

A rabbit model that closely mimics the human eye and a clinical study with cataract patients was used to compare the pharmacokinetics and tissue permeability of TobraDex ST and TobraDex. An in-vitro model was used to assess the bactericidal activity using the rabbit tear concentrations of tobramycin 10 minutes after a single topical dose.

Results

Concentrations of both tobramycin and dexamethasone were greater in the tear film and ocular tissues of rabbits treated with TobraDex ST. There was an 8.3-fold increase in tobramycin concentration in the rabbit tear film 10 minutes after dosing with TobraDex ST compared with TobraDex. Concentrations of tobramycin and dexamethasone in ocular tissues from rabbits exposed to TobraDex ST were up to 12.5-fold greater relative to TobraDex. The in-vitro bactericidal activity (>99.9% kill, 3-log reduction) of TobraDex ST toward tobramycin-resistant and methicillin-resistant Staphylococcus aureus occurred in 90 minutes. TobraDex ST killed Streptococcus pneumoniae 3-log in 5 minutes. TobraDex had no activity toward tobramycin-resistant, methicillin-resistant S. aureus and required approximately 120 minutes for 3-log reduction of S. pneumoniae. In humans, the mean ratio of dexamethasone levels in the aqueous humour at 1 hour was 1.17 in favour of TobraDex ST.

Conclusion

TobraDex ST demonstrated improved suspension formulation characteristics, enhanced pharmacokinetic distribution and improved bactericidal characteristics, and may provide a useful alternative as compared to TobraDex.  相似文献   
105.

Introduction

Antibiotics have traditionally been classified as bactericidal or bacteriostatic. Azithromycin belongs to the parent class of macrolides that are characteristically bacteriostatic. Some evidence suggests that this mol-ecule demonstrates bactericidal kill and has concentration-dependent effects. This study tests the hypothesis that azithromycin demonstrates a bactericidal, concentration-dependent antibiotic effect at concentrations corresponding to and exceeding published tear and conjunctival levels.

Methods

The antibacterial activity of different concentrations of azithromycin 1% in DuraSite® (AzaSite®; Inspire Pharmaceuticals Inc, Durham, NC, USA) was evaluated using a kinetics-of-kill model. Recent conjunctivitis isolates of Staphylococcus aureus, Streptococcus pneumoniae or Haemophilus influenzae were exposed to four concentrations of azithromycin (100, 250, 500 and 750 μg/ml). Starting concentrations were similar to the maximum concentrations (Cmax) that have been demonstrated in conjunctiva (83 μg/g) and tears (288 μg/ml) following topical ocular administration. The percentage of surviving bacteria at 30 and 60 minutes following exposure to each concentration were determined.

Results

Azithromycin failed to demonstrate bactericidal activity (i.e. a 3-log reduction in surviving bacteria) against S. aureus, S. pneumoniae or H. influenzae. Furthermore, the rate and extent of antibacterial activity with azithromycin did not change with higher concentrations, even at the highest tested concentration of 750 μg/ml.

Conclusion

Similar to the parent macrolide class, azithromycin demonstrates bacteriostatic activity against common conjunctival pathogens up to the maximum tested concentration of 750 μg/ml (i.e. 2.6-times and 9-times published Cmax tear and conjunctival concentration, respectively). Azithromycin’s bacteriostatic effects and prolonged elimination half-life will likely lead to a corresponding increase in the emergence of macrolide-resistant isolates.
  相似文献   
106.
目的探讨中医五行音乐疗法对门诊输液患者心理安抚的作用与效果。方法2006年3月-2007年3月,按四时节气的不同,依据中医的五行相克理论,对治疗组的408例门诊输液患者进行音乐干预,而同期对照组396例门诊输液患者不接受音乐疗法。采用自制的调查表,获取他们对环境和服务的满意程度。结果治疗组患者,对门诊输液的满意度较对照组高,差异有统计学意义,P〈0.01。治疗组患者,对医院和本部的投诉率较对照组低,差异有统计学意义,P〈0.01。结论音乐疗法对门诊输液患者的心理有一定的安抚作用。  相似文献   
107.
目的 探讨肾脏受累为主的抗中性粒细胞胞质抗体(ANCA)相关性血管炎患者的预后及其影响因素.方法 对2006-2008年我院诊断的64例肾脏受累为主的ANCA相关性血管炎患者进行回顾性分析,并对其进行前瞻性随访,使用Logistic回归、Cox回归等分析与患者肾脏预后有关的危险因素.结果 ①共入选64例患者,其中男性40例,女性24例,平均年龄(59.9±2.0)岁.随访21~55个月,平均(38±16)个月,期间34例(53%)患者出现死亡或进入长期肾脏替代治疗.②预后不同的2组患者起病时血肌酐[分别为(624±246)、(245±127) μmol/L,t=7.17,P=0.005]、红细胞沉降率(ESR)[分别为(112±24)、(76±48) mm/l h,t=3.74,P<0.01]、血浆白蛋白[分别为(294±31)、(316±42) g/L,t=-2.27,P=0.01]、血红蛋白[分别为(79±13)、(99±33) g/L,t=-3.23,P<0.01 ]差异均有统计学意义.Logistic回归及Cox回归分析证实起病时血肌酐[β=1.004,95%可信区间(CI) 1.002~1.006,P<0.01]及ESR[β=1.018,95%CI1.000~1.037,P=0.046]是预测患者预后的独立危险因素.③ROC曲线结果显示起病时血肌酐和ESR曲线下面积分别为0.95,0.80;敏感性均为94%,特异性分别为93%和70%.结论 以肾脏受累为主的ANCA相关性血管炎患者预后差,起病时血肌酐水平和ESR可能是判断患者预后的重要影响因素.  相似文献   
108.
八项肝纤维化血清标志物比较研究   总被引:36,自引:0,他引:36  
目的比较血清血小板衍生生长因子-BB(PDGF-BB)、转化生长因子-β1(TGF-B1)、基质金属蛋白酶抑制剂-1(TIMP-1)、基质金属蛋白酶-1(MMP-1)、透明质酸(HA)、Ⅲ型前胶原(PC Ⅲ)、Ⅳ型胶原(C Ⅳ)和层黏连蛋白(LN)及外周血单个核细胞(PBMC)内TIMP-1 mRNA、MMP-1 mRNA在肝纤维化中的诊断价值。方法常规肝穿活检、组织病理学诊断;RT-PCR检测PBMCs中MMP-1 mRNA、TIMP-1 mRNA水平;酶标法检测血清PDGF-BB、TGF-β1、TIMP-1和MMP-1含量;放射免疫法检测血清HA、PC Ⅲ、C-Ⅳ和LN含量。结果经ROC曲线分析,血清PDGF-BB、TIMP-1、HA、PC Ⅲ、C-Ⅳ、LN和TIMP-1 mRNA的AUC分别为0.985、0.726、0.318、0.728、0.727、0.583、0.463、0.876;血清PDGF-BB和PBMCs中TIMP-1 mRNA的灵敏度和特异度分别为90%、95%,73.7%、100%;两者联合检测的灵敏度为97.4%,特异度为95.0%。结论八项指标中,血清PDGF-BB的诊断价值最大。在筛选肝纤维化患者时,以血清PDGF-BB、PBMC中TIMP-1 mRNA联合检测最佳。  相似文献   
109.
The Sensitivity of Developing Cardiac Myofibrils to Cytochalasin-B   总被引:6,自引:1,他引:6       下载免费PDF全文
Developing cardiac muscle cells of 11- to 13-somite chick embryos are sensitive to cytochalasin-B. In cultured chick embryos, ranging in development from 11 to 13 somites, hearts stop beating in the presence of this agent. Both polarized light and electron microscopic examination show that cytochalasin-B disrupts existing myofibrils and inhibits the formation of new ones. Discrete Z-bands are not present in treated heart cells and thick, presumably myosin, filaments are found in disarray. These effects are reversible; after cytochalasin-B is removed from the medium, heartbeat recovers and myofibrils with discrete Z-bands reappear. Fibrillar sensitivity appears to be a function of age since fibrils in hearts of embryos having from 22 to 28 pairs of somites are more resistant.  相似文献   
110.
日本血吸虫SjCa8基因的原核表达及其免疫学特征分析   总被引:2,自引:0,他引:2  
目的表达和纯化日本血吸虫钙结合蛋白(SjCa8),研究其免疫学特征。方法重组质粒pET32a ( )-SjCa8经诱导表达后,获取纯化蛋白SjCa8,利用ELISA、Western-blot和动物保护性实验检测SjCa8的免疫学特征。结果成功获取了纯化蛋白SjCa8,该蛋白能免疫识别血吸虫感染小鼠血清和血吸虫病患者血清。SjCa8免疫Balb/c小鼠可获得较高滴度的特异性抗体,诱导宿主产生35.31%的减虫率和35.68%的减卵率。结论纯化蛋白SjCa8具有良好的免疫原性和免疫反应性,具有作为血吸虫病免疫诊断和疫苗候选分子的研究价值。  相似文献   
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