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1.
AimsTo investigate the seasonal variations of HbA1c values in a semi-arid climate among type 2 diabetic patients throughout 11 years of care.MethodsA retrospective cohort study of 2860 patients with 61,187 HbA1c measures. We calculated the averages of HbA1c values of all patients and sub-groups defined by age, gender, BMI, ethnicity, insulin use, smoking status and region of residence, matched to the mean temperature and diurnal range over the 30 and 60 days prior to the HbA1c test date.ResultsWe found a sinusoidal seasonal pattern with statistically significant HbA1c levels gaps between the spring peak and the autumn trough (F = 18.4, P < 0.001). The lowest values were in October-November and the highest in March or August with a difference of 0.17–0.31% (2–4 mmol/mol). We found different relations between the mean temperature and HbA1c depending on season, gender, age, ethnicity and smoking habits.ConclusionThe study identified specific subgroups in which the seasonal influence is particularly marked. A possible explanation is that during hot periods people tend to change their diet and decrease their physical activity, effecting indirectly diabetic imbalance. Recognition of the seasonal variations of HbA1c levels in this geographical region could help physicians with diabetes care and HbA1c control.  相似文献   
2.
IntroductionTemperature and time conditions during storage and distribution of blood components (BC) and their permissible deviations are strictly regulated. The degree of compliance with these requirements in daily practice of transfusion services (TS) is not well known.Materials and methodsWe conducted a survey among Spanish hospital TS covering different aspects of BC management in their daily activity.ResultsEighty-three TS managing 56 % of total transfusions answered the survey. Monitoring of red blood concentrates (RBC) temperature during in-hospital distribution was routinely performed by only 12 % of the TS. The main criterion for BC re-entry into the stock was the total time spent outside controlled temperature. Up to 41 % of the TS apply the “30-minute rule” to distributed RBC, while most services use a 60-minute rule for PC. No adverse events were detected when RBC that had remained longer than 30 or 60 min outside the TS were transfused. Fresh frozen plasma is usually thawed 2 h preissue and stored at 4 °C up to 24 h.Discussion and conclusionsIn the Spanish context, the 30- and 60-minute rules for re-entry of RBC and PC into the TS stock are loosely followed. Feedback for a large number of TS suggests that the extension of the 30-minute RBC rule to at least 60 min is feasible, if other safety requirements are met. Flexibility with some requirements could help reduce product loss without deleterious effect on BC safety.  相似文献   
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BackgroundIt is not known if the tremor associated with an epidural top-up dose for intrapartum caesarean delivery is thermoregulatory shivering. A tremor is only shivering if it has the same frequency profile as cold stress-induced shivering. Thermoregulatory shivering is a response to a reduction in actual body temperature, whereas non-thermoregulatory shivering may be triggered by a reduction in sensed body temperature. This mechanistic study aimed to compare: 1. the frequency profiles of epidural top-up tremor and cold stress-induced shivering; and 2. body temperature (actual and sensed) before epidural top-up and at the onset of tremor.MethodsTwenty obstetric patients received an epidural top-up for intrapartum caesarean delivery and 20 non-pregnant female volunteers underwent a cold stress. Tremor, surface electromyography, core temperature, skin temperature (seven sites) and temperature sensation votes (a bipolar visual analog score ranging from −50 to +50 mm) were recorded.ResultsThe mean (SD) primary oscillation (9.9 (1.9) Hz) frequency of epidural top-up tremor did not differ from that of cold stress-induced shivering (9.0 (1.6) Hz; P=0.194), but the mean (SD) burst frequency was slower (6.1 (1.2) × 10−2 Hz vs 6.9 (0.7) × 10−2 Hz, respectively; P=0.046). Before the epidural top-up dose, the mean (SD) core temperature was 37.6 (0.6) °C. Between the epidural top-up dose and the onset of tremor the mean (SD) core temperature did not change (–0.1 (0.1) °C; P=0.126), the mean (SD) skin temperature increased (+0.4 (0.4) °C; P=0.002) and the mean (SD) temperature sensation votes decreased (−12 (16) mm; P=0.012).ConclusionThese results suggest that epidural top-up tremor is a form of non-thermoregulatory shivering triggered by a reduction in sensed body temperature.  相似文献   
5.
目的:测量热牙胶充填系统携热头工作状态下的实际温度,为临床研究热损伤、观察温度升高对充填材料影响提供理论依据。方法:使用双通道K型电偶温度计测量3种热牙胶充填系统的不同大小携热头和携热头不同部位(工作端尖端和距尖端2 mm、5 mm、10 mm处)的实际温度(设置温度200 ℃),重复测量5次,比较不同充填系统、不同携热头大小、不同测量位点的实际工作温度和设置温度的差异,并用单因素方差分析法分析各因素的影响。结果:BeeFill 40/0.03携热头尖端工作温度最高(198.7±7.7)℃,与设定温度200 ℃差异无统计学意义(P>0.05),其余携热头工作温度均低于设定温度200 ℃,差异有统计学意义(P<0.05),BeeFill 60/0.06携热头距尖端10 mm处温度最低(69.9±4.0) ℃。所有携热头尖端(0 mm)及尖端2 mm处温度较高(112.1~198.7 ℃,中位数140.8 ℃)。结论:大部分热牙胶充填系统的携热头实际工作温度低于设定温度200 ℃。  相似文献   
6.
《Urologic oncology》2015,33(4):168.e1-168.e7
ObjectiveAlthough tissue ablation by irreversible electroporation (IRE) has been characterized as nonthermal, the application of frequent repetitive high-intensity electric pulses has the potential of substantially heating the targeted tissue and causing thermal damage. This study evaluates the risk of possible thermal damage by measuring temperature development and distribution during IRE of porcine kidney tissue.MethodsThe animal procedures were conducted following an approved Institutional Animal Ethics Committee protocol. IRE ablation was performed in 8 porcine kidneys. Of them, 4 kidneys were treated with a 3-needle configuration and the remaining 4 with a 4-needle configuration. All IRE ablations consisted of 70 pulses with a length 90 µs. The pulse frequency was set at 90 pulses/min, and the pulse intensity at 1,500 V/cm with a spacing of 15 mm between the needles. The temperature was measured internally using 4 fiber-optic temperature probes and at the surface using a thermal camera.ResultsFor the 3-needle configuration, a peak temperature of 57°C (mean = 49±10°C, n = 3) was measured in the core of the ablation zone and 40°C (mean = 36±3°C, n = 3) at 1 cm outside of the ablation zone, from a baseline temperature of 33±1°C. For the 4-needle configuration, a peak temperature of 79°C (mean = 62±16°C, n = 3) was measured in the core of the ablation zone and 42°C (mean = 39±3°C, n = 3) at 1 cm outside of the ablation zone, from a baseline of 35±1°C. The thermal camera recorded the peak surface temperatures in the center of the ablation zone, reaching 31°C and 35°C for the 3- and 4-needle configuration IRE (baseline 22°C).ConclusionsThe application of repetitive high-intensity electric pulses during IRE ablation in porcine kidney causes a lethal rise in temperature within the ablation zone. Temperature monitoring should be considered when performing IRE ablation near vital structures.  相似文献   
7.
目的 量化逐日温度对重庆市人群死亡率及寿命损失年(YLL)的影响。方法 利用2010-2013年重庆市主城区全人群死亡个案资料,结合同期气象及空气污染资料,采用分布滞后非线性模型(DLNM)拟合逐日平均气温与逐日死亡数及逐日YLL的关系,分析高温和低温对不同疾病别、不同人群死亡率及YLL的累积滞后效应。结果 日均气温与非意外、心血管系统及呼吸系统疾病死亡的日死亡数和日YLL呈"U"或"W"形。高温当日可增加人群死亡风险,累积滞后效应在第7天时达到最大,持续2周;低温滞后1周后才表现出危害效应,持续时间长达30 d。高温时,日均气温每升高1 ℃,人群非意外、呼吸系统和心血管系统疾病死亡的7 d累积相对危险度(CRR)分别为1.05(95%CI:1.03~1.07)、1.08(95%CI:1.05~1.11)、1.05(95%CI:1.01~1.09),YLL分别为23.81(95%CI:12.31~35.31)年、14.34(95%CI:8.98~19.70)年、4.43(95%CI:1.64~7.21)年;低温时,日均气温每降低1 ℃,人群非意外死亡、呼吸系统和心血管系统疾病死亡的14 d CRR分别为1.06(95%CI:1.04~1.08)、1.09(95%CI:1.06~1.12)、1.06(95%CI:1.02~1.11);YLL分别为23.34(95%CI: 10.04~36.64)年、16.39(95%CI:10.19~22.59)年、2.61(95%CI:-0.61~5.82)年。高温和低温对≥65岁年龄组的影响明显大于<65岁年龄组。高温时,女性死亡率大于男性,男性的YLL大于女性;低温时,女性的死亡率和YLL均大于男性。结论 重庆市高温和低温均可增加人群的死亡风险和YLL,≥65岁年龄组的人群更敏感, 高温对年轻男性影响较大,低温对女性和老年男性影响较大,应有针对性保护极端温度敏感人群。  相似文献   
8.
目的研究南京市温度对死亡的急性效应。方法利用南京市2007—2012年死因、气象、空气污染数据,使用分布滞后非线性模型(DLNM)分析南京市非意外死亡、循环系统疾病死亡以及呼吸系统疾病死亡的冷效应、热效应、极端冷效应和极端热效应的健康风险(RR)。结果非意外死亡、循环系统死亡、呼吸系统死亡的最低死亡温度(MMT)分别为25.2、25.5、25.3℃。非意外死亡的冷效应、极端冷效应、热效应、极端热效应的RR分别为:1.39(95%CI:1.25~1.53)、1.08(95%CI:1.02~1.14)、1.13(95%CI:1.07~1.20)、1.11(95%CI:1.06~1.16);循环系统疾病死亡分别为:1.67(95%CI:1.44~1.94)、1.11(95%CI:1.03~1.20)、1.25(95%CI:1.15~1.36)、1.21(95%CI:1.13~1.29);呼吸系统疾病死亡分别为1.43(95%CI:1.04~1.96)、1.13(95%CI:0.97~1.32)、1.31(95%CI:1.09~1.56)、1.25(95%CI:1.08~1.45)。结论循环系统疾病和呼吸系统疾病为温度影响死亡的敏感疾病,尤其应关注冷效应和极端热效应的健康风险。  相似文献   
9.
【摘要】 目的 优化盐裂皮肤-间接免疫荧光方法(IIF-SSS),评价其在大疱性类天疱疮(BP)抗体检测中的应用。方法 通过调整试验条件,利用正常人包皮或非包皮皮肤制备盐裂底物,分为3组:传统组在4 ℃旋转皮肤48 ~ 72 h;低温浸泡组在4 ℃浸泡皮肤48 ~ 72 h;室温浸泡组在室温25 ℃(23 ℃ ~ 27 ℃)浸泡皮肤24 h。收集2019年8月至2020年8月中国医学科学院皮肤病医院确诊的20例BP患者血清,采用倍比稀释法,利用上述3种试验条件制备的盐裂底物、未盐裂底物进行IIF检测。采用配对样本t检验进行两配对样本的比较。结果 低温浸泡组在48 ~ 72 h未出现真表皮分裂;室温浸泡组非包皮盐裂底物与传统组一样,真表皮分裂界面位于透明板下部。20例BP患者血清,在室温浸泡组盐裂非包皮皮肤、盐裂包皮及传统组盐裂非包皮皮肤这3种底物上,抗体滴度的倒数M(Q1,Q3)分别为5 120(2 560,17 920)、1 280(640,2 560)、1 280(640,2 560)。室温浸泡组制备的盐裂皮肤效果优于传统组,其中19例(95%)BP患者的滴定抗体滴度比传统盐裂方法高出1 ~ 5个倍比稀释度,差异有统计学意义(t = 8.04,P<0.001);而室温浸泡组制备的盐裂包皮与传统组相比,抗体滴度差异无统计学意义(t<0.001,P>0.05)。在以正常未行盐裂的皮肤及包皮为底物的常规IIF中,抗体滴度的倒数分别为320(160,640)、480(160,1 120);室温浸泡组盐裂包皮、非包皮皮肤及传统组盐裂非包皮皮肤这3种底物上 IIF检测的抗体滴度与常规IIF检测的抗体滴度一致或高出1 ~ 7个倍比稀释度,差异有统计学意义(t = 6.47、14.83、5.26,均P<0.001)。结论 采用室温25 ℃(23 ℃ ~ 27 ℃)浸泡法来制备盐裂底物,不仅耗时短,流程简单,而且检测BP抗体的敏感性等于甚至优于传统盐裂方法。  相似文献   
10.
目的:探讨悬浮床治疗老年烧伤患者创面的适宜温度,以提高疗效,减少老年烧伤患者创面疼痛程度及并发症。方法:将入睡悬浮床治疗的20例老年烧伤患者,随机数字表法分为观察组及对照组各10例,两组均入院清创包扎后即入卧悬浮床,观察组将悬浮床的温度设置为30~33℃,对照组温度设置为34~37℃。比较两组患者的创面疼痛、创面干痂形成时间、痂皮厚度、脱痂时间、创面愈合时间、创面细菌培养阳性率及脱水症发生率7项指标。结果:两组患者创面疼痛、创面干痂形成时间、痂皮厚度、脱痂时间、创面愈合时间比较,差异有统计学意义;两组患者创面干痂形成时间比较差异无统计学意义。结论:悬浮床温度设定为34~37℃。治疗老年烧伤患者创面,能减轻疼痛,避免创面损伤,促进创面愈合,提高老年烧伤患者救治成功率。  相似文献   
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