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61.
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Terminal deletions of the chromosome 6q27 region are rare genomic abnormalities, linked to specific brain malformations and other neurological phenotypes. Reported cases have variable sized genomic deletions that harbor several genes including the DLL1 and TBP. We report on an inherited 0.38 Mb terminal deletion of chromosome 6q27 in a 22‐week fetus with isolated bilateral ventriculomegaly and her affected mother using microarray‐based comparative genomic hybridization and fluorescent in situ hybridization (FISH). The deleted region harbors at least seven genes including DLL1 and TBP. The affected mother had a history of hydrocephalus, developmental delay, and seizures commonly associated with DLL1 and TBP 6q27 deletions. This deletion is one of the smallest reported isolated 6q27 terminal deletions. Our data provides additional evidence that haploinsufficiency of the DLL1 and TBP genes may be sufficient to cause the ventriculomegaly, seizures, and developmental delays associated with terminal 6q27 deletions, indicating a plausible role in the abnormal development of the central nervous system.  相似文献   
63.
Background: Natural Killer (NK) cell plays an important role in the innate immune system and is known to produce IFN-γ at an early stage of infection that is essential to eliminate intracellular infection like Leishmania spp. It is already established that Leishmania parasite inhibits the activity of NK cells, avoiding the encounter with the early innate immune response. This, in turn, favors establishment and further dissemination of the infection. Methods: In the present study, we have tried to measure the frequency of different phenotypic subsets of NK cells among visceral leishmaniasis (VL) patients. Results: We have phenotyped three distinct three distinct subsets (CD56CD161+, CD56+CD161, and CD56+CD161+) of NK (CD3) cell using their specific markers CD161 and CD56. Conclusion: Interestingly, we observed selective loss of CD56+CD161+ subset of circulating NK (CD3) cells. Importantly, the other subsets (i.e., CD56?CD161+ and CD56+CD161) of circulating NK cells remain unaffected as compared with healthy subjects.  相似文献   
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The present study was designed to check the serum levels of protease-activated receptor (PAR-1) in patients during different phases of dengue severity. Moreover, a correlation between serum PAR-1 levels and hematological parameters, inflammatory cytokine levels, and liver functional changes was also determined. Based on the World Health Organization criteria, the study population was divided into: nonsevere dengue fever (DF; n = 30), severe dengue hemorrhagic fever (DHF; n = 19), and severe dengue shock syndrome (DSS; n = 11). The platelet count (PLT) and hematocrit (HCT) were analyzed using an automated hematology analyzer and liver function enzymes aspartate transaminase (AST), alanine transaminase (ALT), and alkaline phosphate (ALP), bilirubin were checked by auto-analyzer using diagnostic kits. Moreover, the levels of inflammatory mediators C-reactive protein (CRP), tumor necrosis factor-α (TNF-α), interleukin-6 (IL-6), interleukin-17 (IL-17), and PAR-1 were determined using respective ELISA kits. The HCT levels were elevated and platelet count decreased significantly during dengue complications (DHF and DSS) compared to the DF patients, while the levels of liver functional biomarkers AST, ALT, ALP, and bilirubin remained elevated in DHF and DSS groups than in the corresponding DF group. Similarly, the inflammatory cytokine levels of CRP, TNF-α, IL-6, and IL-17 in DHF and DSS subjects were markedly increased when observed against DF subjects. Notably, the PAR-1 levels were significantly elevated in DHF and DSS groups than in the DF group and positively correlated with changes in HCT levels, inflammatory biomarkers, and liver enzymes. Our findings conclude that PAR-1 levels persistently increased with the severity of the dengue infection and are strongly associated with various clinical manifestations. Thus, PAR-1 levels can be used as a diagnostic marker for assessing dengue severity.  相似文献   
66.
A previously described in-vitro rat granulosa cell plasminogen activator bioassay for FSH has been modified and applied in the assay of human serum. This modified method consists of exposing the diethylstilboestrol-stimulated granulosa cells from 25- to 26-day-old rats to FSH or test substance for 3.5 h in wells coated with 125I-labelled fibrinogen and treated with thrombin. Following stimulation with FSH, the dose-related production of plasminogen activator was measured as the degree of 125I-labelled fibrinolysis in the presence of added plasminogen. Using the urinary FSH/LH bioassay reference preparation as the assay standard, the useful range of the assay was 0.3-15 IU/l, with an assay sensitivity of 0.3 IU/l. As determined using purified glycoprotein hormone preparations, the assay was highly specific for FSH. The minor degree of FSH bioactivity measured in some of the hormone preparations was accounted for by the amount of FSH contamination in these preparations. To abolish interference caused by unknown serum factors, we heat-treated the serum samples for 15 min at 56 degrees C before the assay. The results indicated that neither immunoreactivity nor bioactivity was affected by this treatment. Furthermore, heat-treated human sera gave responses parallel to the standard curve at the three dose levels (2, 4 and 8 microliters) studied. We used this bioassay to estimate the FSH-like bioactivity in 15 human serum samples. The estimates of immunoreactive FSH in these samples correlated well with the corresponding FSH bioactivity (r = 0.745, n = 15 and P less than 0.05). The results indicate that with this sensitive and rapid (completed within 24 h) bioassay, it should be possible to measure FSH bioactivity in heat-treated human serum samples.  相似文献   
67.
Proton magnetic resonance spectroscopy (MRS) is a promising noninvasive diagnostic technique for investigation of breast cancer metabolism. Spectroscopic imaging data may be obtained following contrast‐enhanced MRI by applying the point‐resolved spectroscopy sequence (PRESS) or the stimulated echo acquisition mode (STEAM) sequence from the MR voxel encompassing the breast lesion. Total choline signal (tCho) measured in vivo using either a qualitative or quantitative approach has been used as a diagnostic test in the workup of malignant breast lesions. In addition to tCho metabolites, other relevant metabolites, including multiple lipids, can be detected and monitored. MRS has been heavily investigated as an adjunct to morphologic and dynamic MRI to improve diagnostic accuracy in breast cancer, obviating unnecessary benign biopsies. Besides its use in the staging of breast cancer, other promising applications have been recently investigated, including the assessment of treatment response and therapy monitoring. This review provides guidance on spectroscopic acquisition and quantification methods and highlights current and evolving clinical applications of proton MRS. Level of Evidence 5 Technical Efficacy: Stage 5 J. Magn. Reson. Imaging 2019.  相似文献   
68.
Tumor vasculature and tissue oxygen pressure can influence tumor growth, metastases, and patient survival. Elevated levels of lactate may be observed during the process of aggressive tumor development accompanied by angiogenesis (the evolution of the microenvironment). The noninvasive MR detection of lactate in tumor tissues as a potential biomarker is difficult due to the presence of co‐resonating lipids that are present at high concentrations. Methods were previously reported for lactate editing using the SELective Multiple Quantum Coherence (SelMQC) method. Here we report a sequence “SS‐SelMQC,” Spectral‐Selective SelMQC, which is a modified version of SelMQC using binomial pulses. Binomial pulses were employed in this editing sequence for frequency excitation or inversion of selective lactate resonances. Lactate detection has been demonstrated using SS‐SelMQC, both in vitro (30 mM lactate/H2O doped with 25 μM Gd‐DTPA) and in vivo (Dunning R3337‐AT prostate tumors), and compared to similar measurements made with SelMQC. Lactate areas were measured from nonlocalized spectra, one‐dimensional (1D) localized spectra, and two‐dimensional chemical shift images (CSI) of the localized slice. In data from whole phantoms, the modified pulse sequence yielded enhancement of the lactate signal of 2.4 ± 0.40 times compared to SelMQC. Similar in vivo lactate signal enhancement of 2.3 ± 0.24 times was observed in 1D slice‐localized experiment. Magn Reson Med, 2009. © 2009 Wiley‐Liss, Inc.  相似文献   
69.
70.

Purpose

The management of paediatric mandibular fractures using an acrylic splint is a time-tested procedure. Traditionally, an awl is used to place wires to secure such splints. In this article, we have designed prospective study to compare a new technique of using intravenous cannula stillete (IVCS) as against conventional awl in placement of the circummandibular wires.

Methods

A total of 45 patients were included in the study. Group I included 22 subjects in whom an awl was used, and group II included 23 subjects in whom IVCS was used for placement of circummandibular wires. Parameters such as post-operative pain, swelling and ease of penetration, size of entry and exit wound and injury to adjacent structures were compared.

Results

Statistically significant reduction in post-operative pain and swelling were noticed in groupie. The operating surgeons experienced greater ease in using IVCS, and the size of the entry and exit wounds were also relatively small as compared to using an awl.

Conclusion

The IVCS, which is disposable, having finer diameter, a sharp bevel and internal wire carrying capacity, clearly demonstrates statistically significant advantages over the usage of a conventional awl.  相似文献   
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