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Melissa G. Walker Peter C. Hindmarsh Michael Geary John C.P. Kingdom 《Journal d'obstetrique et gynecologie du Canada》2010,32(12):1134-1139
ObjectiveAdvanced placental maturation (Grannum [G] grade 3) before term is associated with adverse perinatal outcomes associated with placental insufficiency. The nature and timing of the underlying pathology of this process is presently unclear. We hypothesized that advanced placental maturation at 30 to 34 weeks’ gestation is not associated with established second trimester markers of severe placental dysfunction.MethodsIn a cohort study of 1238 low-risk Caucasian women with singleton pregnancies who had sonographic assessment of placental maturation and fetal growth at 34 weeks, the results of maternal serum screening (MSS) and uterine artery Doppler (UtAD) flow studies at 16 weeks were related to adverse perinatal outcomes associated with placental insufficiency: antepartum hemorrhage, preeclampsia, preterm birth < 37 weeks, small for gestational age (< 10th percentile), or postnatal evidence of intrauterine growth restriction (IUGR; ponderal index < 5th percentile).ResultsG1 was found in 127 women (10.3%), G2 was found in 18 women (1.5%), and no cases of G3 were observed. Advanced Grannum grading was significantly associated with IUGR (48 [4.4%] in G0, 9 [7.1%] in G1, 5 [27.8%] in G2; P < 0.001), but was dependent on smoking status. IUGR was not predicted by abnormal MSS or abnormal UtAD findings at either the second or third trimester ultrasounds.ConclusionG2 maturation at 30 to 34 weeks’ gestation is associated with mild IUGR at delivery in low-risk women and with smoking. IUGR was not predicted by either second or third trimester markers of severe placental dysfunction. Future studies directly observing the placenta in the late third trimester may aid the elusive diagnosis of “late-onset” mild IUGR. 相似文献
95.
Sylvia Kocialkowski Herman Yeger John Kingdom Bernard Perbal P. N. Schofield 《Anatomy and embryology》2001,203(6):417-427
NOV, located on human chromosome 8q24.1, was originally cloned following discovery of its avian homolog as a consequence of over-expression
in virally induced nephroblastoma. The gene product is a secreted, modular, protein and a member of the CCN gene family. Evidence
to date indicates that the expression of the wild type protein is associated with cellular quiescence in normal embryonic
fibroblasts yet produces growth stimulatory effects on established murine NIH 3T3 cells. Here we report the expression of
NOV in the first trimester of human embryogenesis, between 5 and 10 weeks. In situ hybridisation and immunohistochemistry reveal
widespread expression in derivatives of all three germ layers. The most abundant sites of expression are in the motor neurons
and floor plate of the spinal cord, adrenal cortex, fusing skeletal, and smooth muscle, the urogenital system and the developing
heart. Additionally, expression is seen in the cranial ganglia, differentiating chondrocytes, gonads, and lung. The sites
of expression suggest strongly that autocrine or paracrine expression of NOV is associated with the process of cell differentiation.
Accepted: 28 February 2001 相似文献
96.
Natural scenes contain localized variations in both first-order (luminance) and second-order (contrast and texture) information. There is much evidence that first- and second-order stimuli are detected by distinct mechanisms in the mammalian visual system. However, in natural scenes the two kinds of information tend to be spatially correlated. Do correlated and uncorrelated combinations of first- and second-order stimuli differentially affect perception? To address this question we employed orientation-modulated textures in which observers were required to discriminate the spatial frequency of the texture modulation. The textures consisted of micropatterns defined as either local variations in luminance (first-order) or luminance contrast (second-order). Performance was robust with textures composed of only first-order micropatterns, but impossible with only second-order micropatterns. However, when the second-order micropatterns were combined with the first-order micropatterns, they enhanced performance when the two were spatially correlated, but impaired performance when the two were spatially uncorrelated. We conclude that local second-order information may enhance texture modulation discrimination provided it is combined with first-order information in an ecologically valid manner. 相似文献
97.
Background
Selection of patients with local failure of nasopharyngeal carcinoma (NPC) for appropriate type of salvage treatment can be difficult due to the lack of data on comparative efficacy of different salvage treatments. The purpose of the present study was to validate a previously published prognostic scoring system for local failures of NPC treated by radiosurgery based on reported results in the literature. 相似文献98.
Background
Oral submucous fibrosis is a common oral health problem in India. This study was conducted to correlate the histopathological diagnosis with habits and clinical findings in patients suffering from oral submucous fibrosis (OSF).Methods
Patients suffering from oral submucous fibrosis from the Departments of Otorhinolayngology and Pathology, Moti Lal Nehru Medical College, Allahabad, India were studied from 2004–2008. Detailed information was gathered in a pretested proforma. Emphasis was given to the various addictions, clinical findings and histological examination was done.Results
Two hundred and thirty nine patients were studied, yielding a male to female ratio of 6.8:1. Maximum patients were in the 21–30 years age group with a marked male predominance. Of these, 197 (82.4%) patients chewed areca nut/dohra, 14 (5.8%) were smokers and 2 (0.8%) patients were habituated to alcohol. 89(37.2%) patients reported difficulty in opening of the mouth (trismus). 51 (57.4%) patients were found to have stage II (2–3 cm) trismus while rest had stage I and III. The buccal mucosa was found to be the most commonly involved site. On the basis of histopathological examination, 52(21.7%) were classified as OSF grade I, 75(31.3%) patients as grade II and 112(46.8%) had grade III disease.Conclusion
The widespread habit of chewing dohra/paan masala is a major risk factor of OSF, especially in the younger age group. In this study, an increase in histopathological grading was found with severity and duration of addiction habit. However no significant correlation was found between clinical staging and histopathological grading. 相似文献99.
Elena Gheorghiu Frederick A.A. Kingdom Manpreet Sull Samantha Wells 《Vision research》2009,49(20):2518-2530
We have employed the shape frequency and shape-amplitude after-effects (SFAE and SAAE) to investigate: (i) whether the shapes of illusory and real curves are processed by the same or different mechanisms, and (ii) the carrier-tuning properties of illusory curvature mechanisms. The SFAE and SAAE are the phenomena in which adaptation to a sinusoidal-shaped contour results in a shift in, respectively, the perceived shape-frequency and perceived shape-amplitude of a test contour in a direction away from that of the adapting stimulus. Both after-effects are believed to be mediated by mechanisms sensitive to curvature (
[Gheorghiu and Kingdom, 2007a] and [Gheorghiu and Kingdom, 2009]; see also Hancock & Peirce, 2008). We observed both shape after-effects in sinusoidally-shaped illusory contours defined by phase-shifted line-grating carriers. We tested whether illusory and real contours were mediated by the same or different mechanisms by comparing same adaptor-and-test with different adaptor-and-test combinations of real and illusory contours. Real contour adaptors produced after-effects in illusory contour tests that were as great as, or even greater than those produced by illusory contour adaptors. However, illusory contour adaptors produced much weaker after-effects in real contour tests than did real contour adaptors. This asymmetry suggests that illusory contour curves are encoded by a sub-set of mechanisms sensitive to real contour curves. We also examined the carrier-tuning properties of illusory-contour curvature processing using adaptor and test illusory contours that differed in the luminance contrast-polarity, luminance scale and orientation of the carriers. We found no selectivity to any of these dimensions for either even-symmetric or odd-symmetric line-gratings carriers, even though selectivity to these dimensions was found for real contours. 相似文献
100.
OBJECTIVE: To evaluate the relationship among peripheral eosinophilia, total IgE, and paranasal sinus mucosal disease based on computed tomography (CT) of the sinus. DESIGN: Retrospective review of a large medical information database from a tertiary referral medical center. SETTING: Tertiary referral medical center specializing in respiratory disorders. PATIENTS: Consecutive patients having total IgE and peripheral eosinophil levels and sinus CT imaging available for review. Patients 18 years or older were included; subjective or objective evidence of chronic rhinosinusitis was not used as selection criteria. A total of 303 patients were found to have peripheral eosinophil levels and CT imaging for review; 288 patients had total IgE levels and CT imaging. MAIN OUTCOME MEASURES: Linear regression analysis was used to evaluate (1) the correlation between peripheral eosinophil level and CT stage of sinus disease and (2) the correlation between total IgE level and CT stage of sinus disease. The CT scans were graded using the Lund-MacKay scoring system. RESULTS: There was a significant positive correlation between sinus CT stage and peripheral eosinophil levels (r=0.60, P<.05). Eighty-nine percent of the abnormal eosinophil counts (>550 cells/microL) were associated with CT scores higher than 12. Total IgE did not correlate with CT stage of disease (r=0.05, P>.05). CONCLUSIONS: The presence of peripheral eosinophilia indicates a high likelihood of mucosal sinus disease based on CT imaging. No correlation was noted between total IgE levels and CT stage of mucosal disease. These data support a link between eosinophilia and the presence of paranasal sinus mucosal inflammation. 相似文献