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121.
Performance characteristics of an ELISA screening assay for urinary synthetic cannabinoids 下载免费PDF全文
Eliani Spinelli Allan J. Barnes Sheena Young Marisol S. Castaneto Thomas M. Martin Kevin L. Klette Marilyn A. Huestis 《Drug testing and analysis》2015,7(6):467-474
Synthetic cannabinoids are marketed as legal alternatives to cannabis, as routine urine cannabinoid immunoassays do not detect synthetic cannabinoids. Laboratories are challenged to identify these new designer drugs that are widely available and represent a major public health and safety problem. Immunoassay testing offers rapid separation of presumptive positive and negative specimens, prior to more costly and time‐consuming chromatographic confirmation. The Neogen SPICE ELISA kit targets JWH‐018 N‐pentanoic acid as a marker for urinary synthetic cannabinoids. Assay performance was evaluated by analyzing 2469 authentic urine samples with the Neogen immunoassay and liquid chromatography‐tandem mass spectrometry (LC‐MS/MS). Two immunoassay cut‐off concentrations, 5 and 10 µg/L, classified samples as presumptive positive or negative, followed by qualitative LC‐MS/MS confirmation for 29 synthetic cannabinoids markers with limits of detection of 0.5–10 µg/L to determine the assay's sensitivity, specificity and efficacy. Challenges at ±25% of each cut‐off also were investigated to determine performance around the cut‐off and intra‐ and inter‐plate imprecision. The immunoassay was linear from 1 to 250 µg/L (r2 = 0.992) with intra‐ and inter‐plate imprecision of ≤5.3% and <9%, respectively. Sensitivity, specificity, and efficiency results with the 5 µg/L cut‐off were 79.9%, 99.7%, and 97.4% and with the 10 µg/L cut‐off 69.3%, 99.8%, and 96.3%, respectively. Cross‐reactivity was shown for 18 of 73 synthetic cannabinoids markers evaluated. Good sensitivity, specificity, and efficiency, lack of sample preparation requirements, and rapid semi‐automation documented that the Neogen SPICE ELISA kit is a viable method for screening synthetic cannabinoids in urine targeting JWH‐018 N‐pentanoic acid. Copyright © 2014 John Wiley & Sons, Ltd. 相似文献
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Cough is an airway defensive reflex substantially consisting in a modified respiratory act. Transection experiments have shown that the fundamental structures responsible for this reflex are located within the medulla oblongata. Electrical stimulation applied to the medulla failed to provide convincing evidence of a cough centre distinct from the brainstem respiratory network. In fact, electrical stimuli affect not only neuronal somata, but also intramedullary cough-related pathways. Studies on the behaviour of medullary respiratory neurones have led to the conclusion that the same respiratory neurones involved in the generation of the eupnoeic pattern of breathing also participate in the production of the cough motor pattern. These findings support the existence of multifunctional neural networks in the mammal brainstem. B?tzinger complex expiratory neurones with augmenting discharge patterns have been suggested to convey an excitatory drive to the expiratory bulbospinal neurones of the caudal ventral respiratory group and, hence, to expiratory motoneurones. The excitatory drive to caudal medullary expiratory neurones is mediated by ionotropic glutamate receptors. Recent lines of evidence indicate that the B?tzinger complex and the caudal ventral respiratory group have a crucial role in determining both the inspiratory and the expiratory components of the cough motor pattern. 相似文献
125.
Enhancer blocking activity located near the 3′ end of the sea urchin early H2A histone gene 下载免费PDF全文
Franco Palla Raffaella Melfi Letizia Anello Maria Di Bernardo Giovanni Spinelli 《Proceedings of the National Academy of Sciences of the United States of America》1997,94(6):2272-2277
The sea urchin early histone repeating unit contains one copy of each of the five histone genes whose coordinate expression during development is regulated by gene-specific elements. To learn how within the histone repeating unit a gene-specific activator can be prevented to communicate with the heterologous promoters, we searched for domain boundaries by using the enhancer blocking assay. We focused on the region near the 3′ end of the H2A gene where stage-specific nuclease cleavage sites appear upon silencing of the early histone genes. We demonstrated that a DNA fragment of 265 bp in length, defined as sns (for silencing nucleoprotein structure), blocked the enhancer activity of the H2A modulator in microinjected sea urchin embryos only when placed between the enhancer elements and the promoter. We also found that sns silenced the modulator elements even when placed at 2.7 kb from the promoter. By contrast, the enhancer activity of the modulator sequences, located downstream to the coding region, was not affected when sns was positioned in close proximity to the promoter. Finally, the H2A sns fragment placed between the simian virus 40 regulative region and the tk promoter repressed chloramphenicol acetyltransferase expression in transfected human cell lines. We conclude that 3′ end of the H2A gene contains sequence elements that behave as functional barriers of enhancer function in the enhancer blocking assay. Furthermore, our results also indicate that the enhancer blocking function of sns lacks enhancer and species specificity and that it can act in transient assays. 相似文献
126.
Luca Morelli Alessandra Perutelli Matteo Palmeri Simone Guadagni Maria Donatella Mariniello Gregorio Di Franco Vito Cela Benedetta Brundu Maria Giovanna Salerno Giulio Di Candio Franco Mosca 《International journal of colorectal disease》2016,31(3):643-652
Purpose
Sexual and urinary dysfunctions are complications in radical treatment of deep infiltrating endometriosis (DIE) with colorectal involvement. The aim of this article is to report the preliminary results of our single-institution experience with robotic treatment of DIE, evaluating intraoperative and postoperative surgical outcomes and focusing on the impact of this surgical approach on autonomic functions such as urogenital preservation and sexual well-being.Methods
From January 2011 through December 2013, a case series of 10 patients underwent robotic radical treatment of DIE with colorectal resection using the da Vinci System. Surgical data were evaluated, together with perioperative urinary and sexual function as assessed by means of self-administered validated questionnaires.Results
None of the patients reported significant postoperative complications. Questionnaires concerning sexual well-being, urinary function, and impact of symptoms on quality of life demonstrated a slight worsening of all parameters 1 month after surgery, while data were comparable to the preoperative period 1 year after surgery. Dyspareunia was the only exception, as it was significantly improved 12 months after surgery.Conclusions
Robot-assisted surgery seems to be advantageous in highly complicated procedures where extensive dissection and proper anatomy re-establishment is required, as in DIE with colorectal involvement. Our preliminary results show that robot-assisted surgery could be associated with a low risk of complications and provide good preservation of urinary function and sexual well-being.127.
Transferrin receptor 1 (TfR1) and putative stimulator of Fe transport (SFT) expression in iron deficiency and overload: an overview 总被引:1,自引:0,他引:1
Transferrin Receptor 1 (TfR1) and putative Stimulator of Fe Transport (SFT) represent two different proteins involved in iron metabolism in mammalian cells. The expression of TfR1 in the duodenum of subjects with normal body iron stores has been mainly localized in the basolateral portion of the cytoplasm of crypt cells, supporting the idea that this molecule may be involved in the sensing of body iron stores. In iron deficiency anemia TfR1 expression demonstrated an inverse relationship with body iron stores as assessed by immunohistochemistry with anti-TfR1 antibodies. In iron overload, TfR1 expression in the duodenum differed according to the presence or absence of the C282Y mutation in the HFE gene, being increased in HFE-related hemochromatosis and similar to controls in non-HFE-related iron overload. SFT is characterized by its ability to increase iron transport both through the transferrin dependent and independent uptake, and could thus affect iron absorption in the intestine. Immunohistochemistry using anti-SFT antibodies which recognize a putative stimulator of Fe transport of approximately 80 KDa revealed a localization of this protein in the apical part of the cytoplasm of enterocytes localized at the tip of the villi. The expression of the protein recognized by these antibodies was increased in iron deficiency, as well as in patients carrying the C282Y HFE mutation. Thus, the increased expression of both proteins only in patients with HFE-related hemochromatosis suggests that other factors should be involved in determining non-HFE-related iron overload. 相似文献
128.
Abstract.Introduction: Magnetocardiographic (MCG) mapping is increasingly used
for the non-invasive study of coronary artery disease (CAD),
cardiomyopathy (CMP) and arrhythmias. MCG study of small animals
with ischemia or CMP would provide useful experimental models
for the interpretation of abnormal human patterns. The aim of
this study was to assess the range of normality of MCG
ventricular repolarization parameters, in intact adult
rats.Methods and
results: 10 adult Wistar rats (weight 250 – 350 grams) were
investigated with a 36-channel MCG mapping instrumentation
(sensitivity is 20 fT/ Hz, at 1 Hz), designed for clinical
recordings in unshielded hospital laboratories. To assess
ventricular repolarization, MCG Q-Tpeak,
Q-Tend, J-Tpeak,
J-Tend,
Tpeak-Tend
intervals were measured. MCG imaging was obtained by automatic
calculation of isofield contour maps, and with inverse source
localization based on the Equivalent Current Dipole and
Effective Magnetic Dipole models, in a semi-infinite space with
homogeneous conductance. Magnetic field (MF) orientation,
dynamics and stability during the J-Tend
segment were also calculated. After averaging 300 s of
continuous MCG recording, the S/N ratio was good enough for
reproducible reconstruction of both atrial and ventricular
magnetic maps and for three-dimensional localization of the
underlying cardiac generators. Clear gender-related differences
in ventricular repolarization duration were found, evidenced by
significantly longer Q-Tend,
J-Tend and
Tpeak-Tend
intervals in females. The differences in MF orientation, and
stability during the J-Tend segment were
not significant. For J-Tpeak MF dynamics,
only the ratio between the strengths of the positive and
negative poles was significantly lower in the female group
(p < 0.05).Conclusions: Contactless MCG recording is a novel approach, which
simplifies non-invasive mapping in small animals. In normal
rats, gender-related differences of ventricular repolarization
parameters equivalent to those reported in previous ECG studies
were demonstrated. 相似文献
129.
130.
Argentiero Donatella Savonitto Stefano D’Andrea Paola Iacovelli Fortunato 《Journal of thrombosis and thrombolysis》2020,49(1):145-148
Journal of Thrombosis and Thrombolysis - Pregnancy-associated acute myocardial infarction is a rare condition usually occurring during the third trimester of pregnancy, and associated with... 相似文献