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971.
In this paper, an intelligent system is presented for interpretation of the Doppler signals of the heart valve diseases based on the pattern recognition. This paper especially deals with combination of the feature extraction and classification from measured Doppler signal waveforms at the heart valve using the Doppler Ultrasound. Because of this, a wavelet packet neural network model developed by us is used. The model consists of two layers: wavelet and multi-layer perceptron. The wavelet layer is used for adaptive feature extraction in the time-frequency domain and is composed of wavelet packet decomposition and wavelet packet entropy. The multi-layer perceptron used for classification is a feed-forward neural network. The performance of the developed system has been evaluated in 215 samples. The test results showed that this system was effective in detecting Doppler heart sounds. The correct classification rate was about 94% for abnormal and normal subjects.  相似文献   
972.
Mutations in the human fibrillin 1 gene (FBN1) cause the Marfan syndrome (MFS), an autosomal dominant connective tissue disorder. Knowledge about FBN1 mutations is important for early diagnosis, management, and genetic counseling. However, mutation detection in FBN1 is a challenge because the gene is very large in size ( approximately 200 kb) and the approximately 350 mutations detected so far are scattered over 65 exons. Conventional methods for large-scale detection of mutations are expensive, technically demanding, or time consuming. Recently, a high-capacity low-cost mutation detection method was introduced based on denaturing high-performance liquid chromatography (DHPLC). To assess the sensitivity and specificity of this method, we blindly screened 64 DNA samples of known FBN1 genotype exon-by-exon using exon-specific DHPLC conditions. Analysis of 682 PCR amplicons correctly identified 62 out of 64 known sequence variants. In three MFS patients of unknown FBN1 genotype, we detected two mutations and eight polymorphisms. Overall, 20 mutations and two polymorphisms are described here for the first time. Our results demonstrate 1) that DHPLC is a highly sensitive (89-99%, P = 0.05) method for FBN1 mutation detection; but 2) that chromatograms with moderate and weak pattern abnormalities also show false positive signals (in all 45-59%, P = 0.05); 3) that the difference in the chromatograms of heterozygous and homozygous amplicons is mostly independent of the type of sequence change; and 4) that DHPLC column conditions, additional base changes, and the amounts of injected PCR products influence significantly the shape of chromatograms. A strategy for FBN1 mutation screening is discussed.  相似文献   
973.
Adults with Down syndrome (DS) represent a unique population who are in need of clinical guidelines to address their medical care. Many of these conditions are of public health importance with the potential to develop screening recommendations to improve clinical care for this population. Our workgroup previously identified and prioritized co‐occurring medical conditions in adults with DS. In this study, we again performed detailed literature searches on an additional six medical conditions of clinical importance. A series of key questions (KQ) were formulated a priori to guide the literature search strategy. Our KQs focused on disease prevalence, severity, risk‐factors, methodologies for screening/evaluation, impact on morbidity, and potential costs/benefits. The available evidence was extracted, evaluated and graded on quality. The number of participants and the design of clinical studies varied by condition and were often inadequate for answering most of the KQ. Based upon our review, we provide a summary of the findings on hip dysplasia, menopause, acquired cardiac valve disease, type 2 diabetes mellitus, hematologic disorders, and dysphagia. Minimal evidence demonstrates significant gaps in our clinical knowledge that compromises clinical decision‐making and management of these medically complex individuals. The creation of evidence‐based clinical guidance for this population will not be possible until these gaps are addressed.  相似文献   
974.
药物洗脱支架用于急性心肌梗死的临床观察   总被引:1,自引:0,他引:1  
目的评价药物涂层支架用于急性心肌梗死的安全性及临床疗效。方法34例发病1周以内的急性心肌梗死患者梗塞相关动脉机械性再灌注治疗时使用药物涂层支架,并于术后3~12个月进行门诊及电话随访,必要时复查冠状动脉造影,观察住院及随访期间心血管事件发生率(死亡、再发急性心肌梗死及血管重建术)。结果37枚药物涂层支架(CYPHER15枚,TAXUS22枚)植入34个梗塞相关动脉(其中3处病变各植入2枚支架),支架长度(22.7±9.0)mm,支架直径(3.1±0.3)mm;10例(29.4%)接受直接经皮冠状动脉介入治疗(PCI),3例(8.8%)为挽救性PCI。支架植入成功率100%。1例(2.9%)支架内急性血栓形成,行急诊血管重建术。平均随访间期(5.9±2.8)个月,2例(5.9%)于随访期间因再发原部位心肌梗死入院治疗,1例因非靶血管病变致心绞痛于术后10个月入院治疗。住院及随访期间无死亡病例发生。结论研究提示药物涂层支架用于急性心肌梗死患者治疗梗塞相关动脉行机械性再灌注安全,可获得与药物涂层支架用于择期的、相对简单的冠状动脉病变的类似疗效。  相似文献   
975.
《Human immunology》2022,83(2):130-133
The stimulation of AT1R (Angiotensin II Receptor Type 1) by Angiotensin II has, in addition to the effects on the renin-angiotensin system, also pro-inflammatory effects through stimulation of ADAM17 and subsequent production of INF-gamma and Interleukin-6. This pro-inflammatory action stimulate the cytokine storm that characterizes the most severe forms of SARS-CoV-2 infection. We studied the effect of AT1Rab on the AT1R on 74 subjects with SARS-CoV-2 infection with respiratory symptoms requiring hospitalization. We divided the patients into 2 groups: 34 with moderate and 40 with severe symptoms that required ICU admission. Hospitalized subjects showed a 50% reduction in the frequency of AT1Rab compared to healthy reference population. Of the ICU patients, 33/40 (82.5%) were AT1Rab negative and 16/33 of them (48.5%) died. All 7 patients positive for AT1Rab survived. These preliminary data seem to indicate a protective role played by AT1R autoantibodies on inflammatory activation in SARS-CoV-2 infection pathology.  相似文献   
976.
This study extends a previous study and confirms that the detection of anti-P30 IgA antibodies is very helpful in the diagnosis of acute acquired or congenital toxoplasmosis. Moreover, we demonstrate that an anti-P30 IgA response can be mounted in the fetuses infected by Toxoplasma gondii during their intra-uterine life as early as week 23 of gestation. A double-sandwich ELISA described in our previous work was used to detect anti-P30 IgA antibodies in 1378 human serum samples collected from 551 patients, including 162 fetuses whose mothers had been infected by T. gondii during pregnancy, 46 congenitally infected and 90 uninfected newborns and 253 women suspected of having been infected during pregnancy, including the mothers of fetuses and newborns previously described. Anti-P30 IgA antibodies were detected in all cases of acute toxoplasmosis but in no case of chronic toxoplasmosis: in the majority of cases, the IgA antibody titre fell below cut-off in 3-9 months. Among the 46 congenitally infected newborns, anti-P30 IgA antibodies were detected in sera of 41 infected newborns (38 at birth, two in the first months of life, one in the seventh month of life), while anti-P30 IgM antibodies were detected in only 30 cases at birth and in one case during the first month of life. Among 162 fetuses, anti-P30 IgA response was observed in five infected fetuses, but was not detected in either 152 uninfected fetuses or in five fetuses considered as infected. The absence or presence of anti-P30 IgA antibodies in the fetus is discussed in relation to the date of maternal infection and collection of the fetal blood. It clearly appears from our study that the combined testing of both IgM and IgA in the fetus and the newborn is essential for a more efficient diagnosis of infection.  相似文献   
977.
978.
目的:为桡骨交锁髓内钉固定术避免桡神经深支损伤提供解剖学依据。方法:前臂标本44侧解剖显露桡神经深支,将肱骨外上髁与Lister结节连线和桡骨头关节面,关节面下1.0、1.5、2.0cm,桡神经深支穿入旋后肌平面,桡神经深支跨越桡骨平面等6个面的交点,依次标记为A、B、C、D、E、F6个点。记录AE、AF的长度,测量B、C、D3个定点在屈肘前臂旋前、中立、旋后位与桡神经深支的水平距离。结果:B、C、D3个定点离桡神经深支的距离越来越近;而对于同一定点,其与桡神经深支的距离按旋前、中立、旋后位的顺序越来越远。结论:桡骨交锁髓内钉固定时,宜于屈肘前臂中立位,在肱骨外上髁与Lister结节连线上,距桡骨头关节面约1.5cm的位置,由前臂后外侧向前内侧插入远端交锁螺丝钉较为安全。  相似文献   
979.
Effects of acute hypoxia on hemodynamics and respiration were studied in acute experiments on narcotized rats. The animals were divided into groups characterized by high, low-, and medium- resistance to hypoxia by the time of respiration arrest during inhalation of gas mixture containing 3% O2. Hemodynamic parameters of highly resistant animals were higher than in low-resistant rats throughout the entire hypoxic period. The development of a rare (with prolonged inspiratory phase) respiratory rhythm in highly resistant rats is an adaptive reaction, which allows them longer tolerate hypoxia compared to low-resistant animals.  相似文献   
980.
衰老大鼠急性肺损伤诱导肾功能受损   总被引:3,自引:0,他引:3       下载免费PDF全文
目的:观察衰老大鼠的急性肺损伤(ALI)是否可进一步诱导肾功能受损。方法:Wistar雄性大鼠40只, 复制成衰老模型, 然后再随机分成对照组(静脉注射生理盐水), ALI组(静脉注射脂多糖, LPS)及LPS组(左心室内注射LPS), 后两组再分2h及6h组。每组8只。注LPS后2h或6h收集血并取肺、肾。制备肺、肾组织匀浆待测。结果:ALI组在注LPS后仅至6h时血中肌酐(Cr)、尿素氮(BUN)含量才有显著升高(均P<0.01)。而LPS组Cr、BUN含量均无显著升高。ALI组血中乳酸(LD)、丙二醛(MDA)及一氧化氮(NO)含量在注LPS后2h时均显著升高(P<0.05, P<0.01);而肺组织中谷胱甘肽过氧化物酶(GSH-PX)及Na+-K+-ATPase活性均显著下降(均P<0.01);上述变化持续至观察的6h时。ALI组在注LPS后仅至6h时, 肾组织中MDA、NO含量才有显著升高(均P<0.01)及GSH-PX、Na+-K+-ATPase活性显著下降(P<0.01)。而在LPS组, 除注LPS后2h时的血中和2h、6h的肺组织中NO含量显著升高(均P<0.05)及2h时的肺组织中Na+-K+-ATPase活性显著下降(P<0.05)外, 其它均无显著变化。结论:给衰老大鼠静脉内注射5mg/kg的LPS可致ALI, 并可进一步诱导肾功能受损。  相似文献   
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