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901.
As an intermediate filament protein, cytokeratin 8 (CK8) exerts multiple cellular functions. Moreover, it has been identified as a marker of notochord cells, which play essential roles in human nucleus pulposus (NP). However, the distribution of CK8 positive cells in human NP and their relationship with intervertebral disc degeneration (IDD) have not been clarified until now. Here, we found the percentage of CK8 positive cells in IDD (25.7±4.14%) was significantly lower than that in normal and scoliosis NP (51.9±9.73% and 47.8±5.51%, respectively, p<0.05). Western blotting and qRT-PCR results confirmed the down-regulation of CK8 expression in IDD on both of protein and mRNA levels. Furthermore, approximately 37.4% of cell clusters were CK8 positive in IDD. Taken together, this is the first study to show a down-regulated CK8 expression and the percentage of CK8 positive cell clusters in IDD based upon multiple lines of evidence. Consequently, CK8 positive cells might be considered as a potential option in the development of cellular treatment strategies for NP repair.  相似文献   
902.
Non-enzymatic and reagentless electrochemical sensors for convenient and sensitive detection of glucose are highly desirable for prevention, diagnosis and treatment of diabetes owing to their unique merits of simplicity and easy operation. Facile fabrication of a three-dimensional (3D) sensing interface with non-enzymatic recognition groups and an immobilized electrochemical probe remains challenge. Herein, a novel non-enzymatic electrochemical sensor was developed for the sensitive and reagentless detection of glucose by loading functional nanostructure on 3D graphene. Monolithic and macroporous 3D graphene (3DG) foam grown by chemical vapor deposition (CVD) served as the electrode scaffold. Prussian blue (PB) and gold nanoparticles (AuNPs) were first co-electrodeposited on 3DG (3DG/PB-AuNPs) as immobilized signal indicator and electron conductor. After a polydopamine (PDA) layer was introduced on 3DG/PB-AuNPs via facile self-polymerization of dopamine to stabilize internal PB probes and offer chemical reducibility, the second layer of AuNPs was in situ formed to assemble the recognition ligand, mercaptobenzoboric acid (MPBA). Owing to the high stability of PB and good affinity between MPBA and glucose, the non-enzymatic sensor was able to be used in reagentless detection of glucose with high selectivity, wide linear range (5 μM–65 μM) and low detection limit (1.5 μM). Furthermore, the sensor was used for the detection of glucose level in human serum samples.

A non-enzymatic electrochemical sensor was fabricated by loading functional nanostructure on three-dimensional graphene foam for reagentless detection of glucose with high sensitivity and stability.  相似文献   
903.
The selection and preparation of an electrode material is the core of capacitive deionization. In order to obtain a material with a good deionization properties, we have designed an environmentally-friendly and simple way of preparing biochar. In this work, biochar was prepared by a thermal-deposition method and after chemical modification it was characterized with a scanning electron microscope (SEM), Fourier transform infrared spectrophotometer (FTIR), X-ray diffraction (XRD) and X-ray photoelectron spectroscopy (XPS). The specific surface area of biochar modified by KOH is as high as 833.76 m2 g−1, but the specific surface area of the unmodified electrode material is only 126.43 m2 g−1. The electrochemical analysis (CV and EIS) of the biochar indicates that HC-800 has a lower charge transfer resistance and a higher specific capacitance, where the specific capacity of HC-800 reaches 120 F g−1. A CDI property analysis of HC-800 shows a better electrosorption capacity of 11.52 mg g−1 and better regeneration and cycling stability than CS-800. The desalination amount remains 87.23% after several cycles.

Schematic illustration of the fabrication of chitin derived biochar and KOH-activated chitin derived biochar electrodes for capacitive deionization.  相似文献   
904.
目的通过文献计量分析,了解2009—2019年我国男护士群体的研究热点及发展趋势,为相关研究提供参考。方法通过万方、CNKI、维普及中国生物医学文献等数据库检索2009—2019年我国男护士相关文献,对纳入文献进行内容分析并使用bicomb 2.0软件和gCLUTO 1.0软件对关键词进行词频分析和双向聚类分析。结果共纳入931篇期刊文献,获得高频关键词25个,通过聚类分析获得3个研究热点,分别为男护士的工作优势与管理、男护士的心理健康以及男护生的护理教育。结论男护士群体的受关注程度日益提高,核心期刊论坛已初具雏形,但整体研究质量不佳,未来需强化科研设计及研究实施的科学性和严谨性,从而提高文献对临床实践的指导价值。  相似文献   
905.
目的:探讨多层螺旋CT(MSCT)与MRI在急性胰腺炎诊断中的临床应用价值。方法:回顾性分析临床疑似急性胰腺炎66例患者的临床、MSCT、MRI资料,采用MSCT与MRI进行检查,将两种影像检查结果与病理结果进行比较得出结论。结果:66例临床疑似为急性胰腺炎患者,MSCT诊断急性胰腺炎为阳性43例,占65.15%(43/66);MSCT平扫主要表现为胰腺体积增大,密度均匀或不均匀,出血区为高密度灶,液化坏死为低密度灶,增强扫描胰腺呈均匀或不均匀明显强化,液化坏死区无强化。MRI诊断急性胰腺炎为阳性51例,占77.27%(51/66);MRI主要表现为胰腺体积肿大,胰腺及胰周积液呈T1低T2高信号。病理诊断急性胰腺炎结果为阳性52例,占78.79%(52/66)。MRI对急性胰腺炎诊断的敏感性、准确性(96.15%、95.45%)明显高于MSCT(75.00%、74.24%),差异有统计学意义(χ2=7.790、9.959,P<0.05)。MRI对急性胰腺炎诊断的特异性(92.86%)高于MSCT(71.43%),但差异无统计学意义(χ2=0.974、P=0.324)。结论:MRI对急性胰腺炎诊断的敏感性、特异性、准确性均高于MSCT,对于急性胰腺炎MSCT检查有禁忌证、需要多次复查的患者,MRI检查具有更大的优势。  相似文献   
906.
Optical sectioning has been widely employed for inhibiting out-of-focus backgrounds in three-dimensional (3D) imaging of biological samples. However, point scanning imaging or multiple acquisitions for wide-field optical sectioning in epi-illumination microscopy remains time-consuming for large-scale imaging. In this paper, we propose a single-scan optical sectioning method based on the hybrid illumination (HiLo) algorithm with a line-illumination strategy. Our method combines HiLo background inhibition with confocal slit detection. It thereby offers a higher optical sectioning capability than wide-field HiLo and line-confocal imaging without extra modulation and multiple data acquisition. To demonstrate the optical-sectioning capability of our system, we imaged a thin fluorescent plane and different fluorescence-labeled mouse tissue. Our method shows an excellent background inhibition in thick tissue and thus potentially provides an alternative tool for 3D imaging of large-scale biological tissue.  相似文献   
907.
Automatic detection of retinopathy via computer vision techniques is of great importance for clinical applications. However, traditional deep learning based methods in computer vision require a large amount of labeled data, which are expensive and may not be available in clinical applications. To mitigate this issue, in this paper, we propose a semi-supervised deep learning method built upon pre-trained VGG-16 and virtual adversarial training (VAT) for the detection of retinopathy with optical coherence tomography (OCT) images. It only requires very few labeled and a number of unlabeled OCT images for model training. In experiments, we have evaluated the proposed method on two popular datasets. With only 80 labeled OCT images, the proposed method can achieve classification accuracies of 0.942 and 0.936, sensitivities of 0.942 and 0.936, specificities of 0.971 and 0.979, and AUCs (Area under the ROC Curves) of 0.997 and 0.993 on the two datasets, respectively. When comparing with human experts, it achieves expert level with 80 labeled OCT images and outperforms four out of six experts with 200 labeled OCT images. Furthermore, we also adopt the Gradient Class Activation Map (Grad-CAM) method to visualize the key regions that the proposed method focuses on when making predictions. It shows that the proposed method can accurately recognize the key patterns of the input OCT images when predicting retinopathy.  相似文献   
908.
BACKGROUNDInguinal hernia is a common clinical manifestation in children with a low self-healing rate. AIMTo determine the effect of laparoscopic surgery on indirect inguinal hernia and the risk factors for postoperative recurrence and to provide a reference for the clinical treatment and prevention of recurrence.METHODSWe selected 360 children who underwent laparoscopic high ligation in our hospital as the laparoscopic group and 120 patients treated for inguinal hernia with conventional surgery as the control group. The operation time, blood loss, incision length, hospitalization time, total hospitalization cost and surgical complications were compared between the two groups. According to telephone follow-up or return visits, the children who had recurrence within 2 years after the operation in the laparoscopic group were analyzed, and the laparoscopic high ligation hernia sac level was analyzed by the logistic multifactor method. Ligation was used to treat recurrence in children with inguinal hernia.RESULTSThe operation time, blood loss, length of incision, and length of hospital stay in the laparoscopic group were lower than those in the control group (P < 0.05). The total hospitalization cost in the laparoscopic group was higher than that in the control group (P < 0.05). The operative complication rate was 1.67% lower than that in the control group (12.50%) (P < 0.05). In 360 children with laparoscopic high ligation of the hernia sac, 14 patients had recurrence within 2 years after surgery. After analysis, 14 cases in the recurrence group did not recur. The preoperative incarceration rate, inner ring diameter, ligature use and age difference were statistically significant (P < 0.05). According to logistic regression multivariate analysis, an inner ring diameter ≥ 1.0 cm, the use of an absorbable ligature line and age > 3 years increased the risk of postoperative recurrence in children with inguinal hernia after laparoscopic high ligation of the hernia sac (P < 0.05). CONCLUSIONLaparoscopic surgery for indirect inguinal hernia in children has the advantages of low trauma and a rapid postoperative recovery. An inner ring diameter ≥ 1.0 cm, the use of absorbable ligature, and age > 3 years may increase the risk of recurrence after laparoscopic high ligation of the hernia sac.  相似文献   
909.
910.
BACKGROUNDSince the outbreak of the coronavirus disease 2019 (COVID-19) pandemic, the exclusion of a patient from COVID-19 should be performed before surgery. However, patients with type A acute aortic dissection (AAD) during pregnancy can seriously endanger the health of either the mother or fetus that requires emergency surgical treatment without the test for COVID-19. CASE SUMMARYA 38-year-old woman without Marfan syndrome was admitted to the hospital because of chest pain in the 34th week of gestation. She has diagnosed as having a Stanford type-A AAD involving an aortic arch and descending aorta via aortic computed tomographic angiography. The patient was transferred to the isolated negative pressure operating room in one hour and underwent cesarean delivery and ascending aorta replacement. All medical staff adopted third-level medical protection measures throughout the patient transfer and surgical procedure. After surgery, the patient was transferred to the isolated negative pressure intensive care unit ward. The nucleic acid test and anti-COVID-19 immunoglobulin (Ig) G and IgM were performed and were negative. The patient and infant were discharged without complication nine days later and recovered uneventfully. CONCLUSIONThe results indicated that the procedure that we used is feasible in patients with a combined cesarean delivery and surgery for Stanford type-A AAD during the COVID-19 outbreak, which was mainly attributed to rapid multidisciplinary consultation, collaboration, and quick decision-making.  相似文献   
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