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991.
目的 利用儿童阻塞性睡眠呼吸暂停疾病特异性生活质量调查表(OSA-18量表)评估阻塞性睡眠呼吸暂停(OSA)患儿在手术干预前后的生活质量变化,分析患儿术后生活质量评分增高可能的影响因素。方法 2018年5月~2019年5月入院接受手术治疗的2~12岁OSA患儿152例。患儿监护人分别在术前,术后3个月、6个月、1年填写OSA-18量表。收集相关病史资料,利用多元线性回归对患儿术前、术后生活质量评分进行统计学分析,探讨与术后评分增高相关的影响因素。结果 152例患儿的平均年龄为(4.82±1.89)岁,59%为男性。与术前[(68.5±15.5)分]相比,术后OSA-18总分在3个月[(44.0±15.5)分]、6个月[(42.4±14.7)分]和1年[(38.7±13.4)分]均显著下降(P值均<0.001)。术前量表5个维度的得分与术后各个时间点相比也均显著下降(P值均<0.001)。比较患儿术后3个月与6个月的总分及各维度评分,除睡眠障碍(P=0.038)外,其余差异均无统计学意义。身体症状评分在术后各个时间点差异也均无统计学意义。根据多元线性回归分析,术前白天功能(P=0.021)是术后3个月生活质量评分增高的影响因素;免疫球蛋白E(P<0.001)和术前身体症状(P=0.027)是术后6个月的影响因素;而患儿性别(P=0.012)则是术后1年的影响因素。结论 手术干预可以给OSA患儿的生活质量带来长期持续性的提高。不同影响因素可能会引起患儿术后不同时期生活质量的下降。  相似文献   
992.
目的研究多药耐药基因MDR1 C3435T基因多态性对质子泵抑制剂联合阿莫西林与克拉霉素三联1周疗法根除幽门螺杆菌(砀,)治疗的影响。方法选取101例却阳性的慢性胃炎或消化性溃疡患者,分成2组,分别进入埃索美拉唑联合阿莫西林与克拉霉素方案(EAC)或奥美拉唑联合阿莫西林与克拉霉素方案(OAC)进行1周根除治疗。采用聚合酶链反应-限制性内切片段长度多态性(polymerase chain reaction-restriction fragment length polymorphism,PCR-RFLP)的方法检测MDR1 C3435T基因型,比较不同基因型患者之间埤,根除率的差异。结果MDR1 CC3435、C3435T和3435TT的却根除率分别为72.4%、88.2%和81.0%。MDR1 C3435T各基因型组间却根除率比较均元显著性差异。结论MDR1 C3435T基因多态性与却根除疗效无显著相关性。  相似文献   
993.
AIM: To evaluate aspects of cognition impacted by individuals with and without normal tension glaucoma. METHODS: Fifty normal tension glaucoma (NTG) and 50 control patients ≥50y of age were recruited from the UCSF Department of Ophthalmology. Demographic data and glaucoma parameters were extracted from electronic medical records for both groups. Tests of executive function [Executive Abilities: Measures and Instruments for Neurobehavioral Evaluation and Research (EXAMINER)] and learning and memory [California Verbal Learning Test–Second Edition (CVLT-II)] were administered to both NTG and controls. Race, handedness, best-corrected visual acuity, maximum intraocular pressure, optic nerve cup-to-disc ratio, visual field and optic nerve optical coherence tomography parameters, and a measure of general health (Charlson Comorbidity Index) were compared between NTG and controls as well as within NTG subgroups. Multivariate linear regression was used to compare group performances on the EXAMINER battery and CVLT-II while controlling for age, sex, and years of education. RESULTS: NTG and controls were comparable with respect to age, sex, race, education, handedness, and the Charlson Comorbidity Index (P>0.05 for all). Performance on the EXAMINER composite score and the CVLT-II did not differ between NTG and controls (P>0.05 for both). CONCLUSION: This is the first prospective study in which the cognitive function of subject with NTG were evaluated using a comprehensive, computerized neurocognitive battery. Subjects with NTG do not perform worse than unaffected controls on tests of executive function, learning, and memory. Results do not support the hypothesis that individuals with NTG are at higher risk for cognitive dysfunction and/or dementia.  相似文献   
994.
目的 比较蠕形螨的检测方法,了解我校医学生蠕形螨感染情况,分析蠕形螨感染的相关因素.方法 分别采用透明胶纸法、刮脂法、挤刮法对612名学生进行蠕形螨检测,并通过问卷调查分析蠕形螨感染的相关因素.结果 透明胶纸法、刮脂法和挤压检测的感染率分别为21.73%、14.71%、15.35%.透明胶纸法检测的感染率高于其他2种方法,大学生蠕形螨感染率为21.73%,油性皮肤和混合性皮肤感染率与干性皮肤感染率相比差异具有统计学意义,油性皮肤和混合性皮肤感染率较高,面部健康者和面部疾患者感染率无统计学意义.结论 在以后的教学中采用透明胶纸法检测蠕形螨,大学生以轻度感染为主,蠕形螨感染与生活习惯、皮肤性状、集体生活因素密切相关.  相似文献   
995.
最近研究发现,12/15-脂加氧酶的过表达或激活可能促进了糖尿病肾病和神经病变的进展.该酶可催化花生四烯酸产生12-羟基二十碳四烯酸和15-羟基二十碳四烯酸,从而影响细胞结构、代谢和信号转导.研究发现12/15-脂加氧酶及其代谢产物可直接诱导或间接调节细胞因子导致细胞肥大、增殖和细胞外基质堆积,参与糖尿病肾病的发生.此外,该酶的过表达和激活与外周神经系统的氧化-硝化应激相关,可能参与糖尿病神经病变的发生.因此,12/15-脂加氧酶抑制剂或包含抑制剂的联合治疗可能为糖尿病微血管并发症的治疗提供新的研究方向.  相似文献   
996.
目的拯救狂犬病毒HEP-Flury-mEG株,为疫苗制备奠定基础。方法将ERA株G蛋白333位毒力位点修饰为谷氨酸后替换至HEP-Flury株基因组。重组感染性克隆质粒和4个辅助质粒,共转染BHK-21细胞,拯救重组病毒。结果 IFA鉴定成功拯救出了HEP-Flury-mEG株狂犬病病毒。重组病毒G基因经XholⅠ酶切,片段大小为1 071bp和520bp,与预期结果相符。重组病毒在BHK-21细胞中传代4次,滴度维持在1×107.5 FFU/ml。重组病毒经常规负染后在电镜下为弹状粒子,长度和直径与亲本株一致。结论获得了重组狂犬病毒HEP-Flury-mEG株。该病毒滴度高,形态完整,传代稳定,为进一步研究狂犬病毒病毒的生物学特性和新型基因工程疫苗奠定了基础。  相似文献   
997.
Complex space environments, including microgravity and radiation, affect the body''s central nervous system, endocrine system, circulatory system, and reproductive system. Radiation-induced aberration in the neuronal integrity and cognitive functions are particularly well known. Moreover, ionizing radiation is a likely contributor to alterations in the microbiome. However, there is a lacuna between radiation-induced memory impairment and gut microbiota. The present study was aimed at investigating the effects of simulated space-type radiation on learning and memory ability and gut microbiota in mice. Adult mice were irradiated by 60Co-γ rays at 4 Gy to simulate spatial radiation; behavioral experiments, pathological experiments, and transmission electron microscopy all showed that radiation impaired learning and memory ability and hippocampal neurons in mice, which was similar to the cognitive impairment in neurodegenerative diseases. In addition, we observed that radiation destroyed the colonic structure of mice, decreased the expression of tight junction proteins, and increased inflammation levels, which might lead to dysregulation of the intestinal microbiota. We found a correlation between the brain and colon in the changes in neurotransmitters associated with learning and memory. The 16S rRNA results showed that the bacteria associated with these neurotransmitters were also changed at the genus level and were significantly correlated. These results indicate that radiation-induced memory and cognitive impairment can be linked to gut microbiota through neurotransmitters.

Exposure to 60Co-γ ray impacts learning and memory ability as well as the cell morphology and neurotransmitters in hippocampus, even disrupts the bacterial community in colon.  相似文献   
998.
Vibrio vulnificus is a ubiquitous marine bacterium that may cause rapid and deadly infection, threatening lives of people living around natural bodies of water, especially in coastal regions. However, traditional culture-based methods are time-consuming and unable to detect Viable But Non-Culturable (VBNC) V. vulnificus cells. In this work, we isolated a batch of detection aptamers specifically binding to V. vulnificus in all culture status. With traditional whole bacteria-SELEX (Systematic Evolution of Ligands by EXponential enrichment), flow cytometer analysis and imaging, we identify 18 candidates and validated two of them (V8 and V13) as applicable aptamers. Their truncated sequences also showed comparable performance. The dissociation constant (KD) value of V8 is shown to be as low as 11.22 ± 1.32 nM. Optimal aptamers V8 and V13 are also validated to be effective to detect different Vibrio vulnificus strains under different binding environments using flow cytometry. As for detection parameters, the LOD of the V8 from cytometry is 29.96 CFU mL−1, and the linear range is 102–5 × 105 CFU mL−1. This is the first case demonstrating that aptamers can detect the existence of VBNC bacteria as well as live bacteria.

With whole-bacteria SELEX, we got aptamers that can bind to V. vulnificus in VBNC Status for the first time.  相似文献   
999.
In order to explore the reforming process of biomass pyrolysis oil in depth, the catalytic steam reforming (SR) of crude bio-oil (BIO) derived from rapid pyrolysis of rice husk and its derivatives for hydrogen production was studied by means of a bench-scale fixed-bed unit combined with the FTIR/TCD technique. The physico-chemical properties and compositions of BIO were determined. Acetic acid (HOAc), ethylene glycol (EG), acetone (ACE) and phenol (PHE) were selected as four representative bio-oil derivatives. Evolution characteristics of H2, CO, CO2 and CH4 during SR of HOAc, EG, ACE, PHE and BIO were revealed and compared. The hydrogen yield increased sharply with reaction time to the peak values of 24.7%, 32.3%, 16.4%, 25.6% and 24.9%, corresponding to HOAc, EG, ACE, PHE and BIO, respectively. After that, the yield of hydrogen exhibited a downward trend, suggesting that the catalyst ability for selective hydrogen production gradually decreased. The H2 yield from EG was the highest, followed by PHE, HOAc, BIO and ACE. The order of CO yields from large to small was EG > HOAc > ACE > BIO ≈ PHE. The percentages of coke deposited on catalyst were arranged in descending order as HOAc > BIO > ACE > PHE > EG. This study could provide more detailed information on the catalytic reforming mechanism of bio-oil on the one hand, and also point out the direction for the improvement of the catalysts, which play a role in ensuring the high yield of H2 while converting CO to H2 through the water gas shift reaction.

Evolution of H2, CO, CO2 and CH4 during catalytic steam reforming of the bio-oil and its different derivatives was revealed.  相似文献   
1000.

Purpose

Evaluate the accuracy of five different techniques for lower cervical pedicle screw placement.

Methods

Forty human cadaveric cervical spines were equally divided into five groups, and each group had eight specimens. Pedicle screws with dia. 3.5 mm were used. Group 1 was blind screw placement without any assistance; Group 2–5 was assisted by the X-ray fluoroscopy, virtual fluoroscopy navigation system, CT-based navigation system, and Iso-C 3D navigation system, respectively. Thereafter, cortical integrity of each pedicle was evaluated by anatomic dissection of the specimens.

Results

A total of 398 pedicle screws were inserted. In the Group 1–5, the average operation time per sample was 27 ± 3.0, 112 ± 10.3, 69 ± 6.4, 98 ± 11.0, and 91 ± 6.0 min, respectively. The outcome for excellent, fair and poor were 29 (36.3 %), 21 (26.2 %) and 30 (37.5 %) in Group 1; 35 (44.9 %), 29 (37.2 %) and 14 (17.9 %) in Group 2; 34 (42.5 %), 36 (45.0 %) and 10 (12.5 %) in Group 3; 70 (87.5 %), 10 (12.5 %) and 0 (0.0 %) in Group 4; 72 (90.0 %), 8 (10.0 %) and 0 (0.0 %) in Group 5.

Conclusions

Blind screw placement was surely unsafe. Lower cervical pedicle screw placement assisted by the CT-based navigation system or the Iso-C 3D navigation system significantly improved the accuracy compared to the fluoroscopy assistance and the virtual fluoroscopy navigation assistance.  相似文献   
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