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IntroductionEndocan levels were found to be associated with severity and mortality of the respiratory system diseases.ObjectiveWe aimed to figure out whether endocan was an important marker for the diagnosis, severity and follow-up of bronchopulmonary dysplasia (BPD).Materials and methodsInfants with moderate/severe BPD, and who required hydrocortisone treatment were included in the study group. Infants without BPD were allocated in the control group. Endocan levels were compared between the control group and the study group, and before and after the treatment in the study group.ResultsA total of 148 infants, 74 infants in the control group and 74 infants in the BPD group, were included. The endocan level was higher in the BPD group than in the control group (P = .001). Endocan levels before treatment in the BPD group was found to be higher than endocan level after treatment (P = .021).ConclusionOur study found that endocan levels increased in moderate/severe BPD. Serum endocan levels may be a safe and novel indicator for the follow-up of response to treatment and the prognosis of the severity of the disease.  相似文献   
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急性心肌梗死经皮冠状动脉介入治疗后心肌灌注的方法评价   总被引:13,自引:0,他引:13  
目的 联合应用TIMI心肌灌注分级 (TMP)、校正的TIMI画面记帧 (CTFC)、心电图ST段变化 (sumSTR)方法评价急性心肌梗死 (AMI)急诊经皮冠状动脉介入治疗 (PCI)后心肌灌注程度 ,探讨心肌灌注程度对临床预后的影响。方法  77例AMI患者PCI后即刻采用TMP CTFC、TMP sumSTR、CTFC sumSTR三种联合方法评价心肌灌注程度 ,PCI术后 1个月检查双核素心肌灌注显像 ,记录 6个月心脏事件。结果 评价心肌灌注程度 ,与双核素心肌灌注显像对比 ,TMP sumSTR敏感性 86 7%、特异性 85 7%、准确性 86 2 % ;TMP CTFC敏感性 80 %、特异性 77 1%、准确性 78 5 % ;多变量回归分析TMP 0 / 1级 sumSTR <30 %为 6个月心脏事件的独立危险因子 (OR=2 1 5 ,95 %可信区间 2 7~ 6 5 7,P =0 0 0 3) ;Kaplan Meier分析曲线显示TMP sumSTR方法评价的心肌灌注不良组 6个月心脏事件高于心肌灌注良好组 (P <0 0 5 )。结论 TMP sumSTR、TMP CTFC能更好的评价心肌灌注程度 ;TMP sumSTR可预测 6个月心脏事件。  相似文献   
34.
卡介菌多糖核酸治疗小儿咳嗽变异性哮喘   总被引:1,自引:0,他引:1  
谢红 《华西医学》2009,24(2):421-422
目的:观察卡介菌多糖核酸注射液在小儿咳嗽变异性哮喘治疗应用的疗效。方法:将本科40例咳嗽变异性哮喘患儿,随机分为治疗组和对照组(各20例)。治疗组给予BCG—PSN+必可酮气雾剂,对照组:给予单用必可酮气雾剂吸入,连续吸入6周,观察疗效,并进行统计学处理。结果:治疗组总有效率为95%,对照组总有效率为70%,统计学处理总有效率有显著差异(P〈O.01)。结论:卡介菌多糖核酸(polysaccharide nucleic acidfraction of BCG,BCG—PSN)能有效地控制咳嗽变异性哮喘(CVA)的呼吸道的反复感染,提高免疫功能;与必可酮配合,能有效地控制CVA的复发。  相似文献   
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In this, the third paper of the series, the loudness of low-rate bursts of electrical pulses was measured as a function of the burst duration, in subjects implanted with the Nucleus® 24 cochlear implant system (three with straight and two with Contour™ electrode arrays). In order to help distinguish between the contributions of peripheral and more central effects, the ECAP was recorded to the individual pulses comprising the bursts, using the Neural Response Telemetry™ (NRT™) system. At a pulse rate of 250 pulses/s, the ECAP amplitude did not decrease greatly during the bursts: the mean reduction factor was 0.89. The time-constant for summation of the loudness contributions from the pulses comprising a burst was found to be larger than that associated with normal hearing. In addition, the first pulse of a pulse train was found to contribute much more to the overall loudness than did the subsequent pulses, although a corresponding difference was not observed in the ECAP recordings. These results establish a necessary connection between the essentially single-pulse model, developed in the fourth and fifth papers of the series, and the psychophysical data for pulse bursts, but they also have broader implications.  相似文献   
37.
目的比较瑞芬太尼和瑞芬太尼联合硝酸甘油在全麻下鼻内镜手术中控制性降压效果。方法鼻内镜下鼻息肉、鼻窦炎手术病人共40例,ASAⅠ或Ⅱ级,用随机数字表分为瑞芬组和瑞硝组,每组20例,咪达唑仑、丙泊酚、瑞芬太尼和维库溴铵静脉复合全麻气管插管,2组术中均以瑞芬太尼0.1~0.2μg·kg~(-1)·min~(-1)、丙泊酚2~5 mg·kg~(-1)·h~(-1)持续泵输,维库溴铵4 mg·h~(-1),静脉注射。瑞硝组加用硝酸甘油静脉滴注,开始剂量5μg·min~(-1),调节滴速使收缩压维持在12 kPa(90 mmHg)左右。观察降压前(T_0)、降压后5 min(T_1)、30 min(T_2)、60 min(T_3)和停止降压后5 min(T_4)的收缩压和心率,计算心肌氧耗指数,瑞芬太尼、丙泊酚用量,手术时间和病人苏醒时间。结果2组病人年龄、性别和体重间差别无统计学意义(P>0.05)。T_1时2组血压明显下降,与T_0比较,均P<0.01,且瑞硝组降压程度明显大于瑞芬组(P<0.01),降压后的T_1,T_2瑞硝组心率加快,与瑞芬组相比有非常显著意义(P<0.01);降压期的氧耗指数,瑞硝组低于瑞芬组(P<0.05,P<0.01);停止降压后,瑞芬组血压和心率变化与T_3比,无统计学意义(P>0.05),但瑞硝组血压和心率均明显增加(P<0.01);瑞芬组的瑞芬太尼、丙泊酚用量和手术时间明显大于瑞硝组(P<0.01),2组病人的苏醒时间差异无统计学意义(P>0.05)。结论鼻内镜手术瑞芬太尼在常用剂量范围内作控制性降压虽比较平稳,但难以达到目标血压,联合硝酸甘油后效果明显,并可减少麻醉药用量和手术时间,减少病人医疗费用。  相似文献   
38.
To determine whether acute alcohol ingestion during pregnancy could affect fetal myocardial function, studies were carried in six chronically catheterized fetal sheep during maternal alcohol infusion. Absolute ethyl alcohol (0.8 ml/kg) was administered to the mother over 10 minutes via the jugular vein. These infusions were repeated every 30 minutes during 3 hours, and peak maternal and fetal blood concentrations close to 200 mg/dl alcohol were reached. Fetal PCO2 decreased from a baseline of 43.15 +/- 3.75 to 36.13 +/- 2.6 torr 1 hour after the start of alcohol infusion (P less than 0.05). Similarly, pH rose from 7.37 +/- 0.027 to 7.44 +/- 0.015 (P less than 0.05). Both values returned to baseline level at the end of alcohol infusion. PO2 remained within physiologic limits. The systolic time intervals of the fetal heart showed a rapid and prolonged modification. The pre-ejection period from 58 +/- 8 to 66 +/- 4 msec (P less than 0.05) during the infusion; this change was related to an increase in the isometric contraction period. The ratio of the pre-ejection period over the ejection time was also significantly increased (P less than 0.01), and remained elevated until the end of the experiment (12 hours). A rise in fetal systolic and diastolic pressures was observed at about 2 hours after the start of the alcohol infusion, and lasted 4 hours. This study suggests that an episode of maternal alcohol intoxication causes rapid depression of fetal myocardial contractility that is maintained several hours after cessation of alcohol ingestion.  相似文献   
39.
Aromatase converts androgen to estrogen, a hormone that plays an important role in the development of breast cancer. Aromatase inhibitors have been shown to be a useful endocrine regimen for estrogen-dependent breast cancer. Structure-function studies of aromatase can generate critical structural information for designing highly potent and specific inhibitors. However, aromatase structure-function studies have been hampered by a lack of purified protein. In this report, we describe the construction and expression of a recombinant derivative of human aromatase in Escherichia coli using the pET vector system, and the purification of the enzyme by means of nickel-agarose affinity chromatography. We examined the expression of the full-length, Del-38, C-6xHis-tagged Del-38, and NC-6xHis-tagged Del-38 forms of aromatase. The recombinant aromatase without the first 38 amino acids from the amino-terminus (i.e. Del-38) was found to have a higher activity than the full-length enzyme. Moreover, the addition of two separate hexameric histidine tags at both the amino and the carboxyl-termini (i.e. NC-6xHis-tagged Del-38) increased the binding affinity of the recombinant enzyme to the nickel-agarose. The expressed aromatase (i.e. NC-6xHis-tagged Del-38 aromatase) was eluted from the nickel-agarose with 80 mM EDTA. The total aromatase activity of the 80 mM EDTA-eluted fractions was significantly higher than the detergent-solubilized protein extract, indicating a renaturation process during the nickel-agarose affinity chromatography. Purified aromatase exhibited a single band when analyzed by SDS-PAGE, and activity up to 5.8 nmol/mg/min was obtained using the tritiated water release assay. The K(m) value for androstenedione was determined to be 62+/-24 nM by enzyme kinetic analysis. The recombinant aromatase preparation was also characterized by reduced CO-difference spectral analysis, reaction product extraction assay, and inhibition studies using two aromatase inhibitors (letrozole and anastrozole). The results indicate that the recombinant aromatase from E. coli has catalytic properties identical to those of the enzyme expressed in human tissue and will be very useful for further structure-function studies of aromatase.  相似文献   
40.
分析了典型的生活垃圾填埋场沉降经验模型(Ling et al.模型)、土壤动力学模型(Sowers模型和ISPM模型)的机理,并依据法国某城市生活垃圾填埋场为期4 a的现场实际沉降量监测结果,率定了3种模型的模型参数,据此预测了相应填埋堆体的长期沉降情况,比较讨论了各模型预测结果的差异,并对预测结果进行了验证.结果表明,各模型短期预测结果与实测值偏差都不大,可作为填埋场短期附加库容估算的工具;从模型预测结果的准确性和便于应用2方面综合考虑,Sowers模型更为合适;对于填埋堆体高度大约为26 m的填埋单元,最终覆土30 a后填埋堆体沉降量可达填埋堆体高度的21%~27%.  相似文献   
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