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排序方式: 共有1004条查询结果,搜索用时 15 毫秒
31.
Hentschel J Ruff R Juette F von Gontard A Gortner L 《American journal of perinatology》2007,24(10):611-618
Infants born by caesarean section (CS) near or at term were observed to display spontaneous facial movements in their first minutes. We hypothesized that those are reproducible. Up to now, nothing was known about the significance, frequency, and determinants of such facial activity. Repetitive eye opening (EO) and tongue thrust (TT) actions were documented during 1 to 5 minutes, 5 to 10 minutes, and 1 to 15 minutes in 102 infants. In addition, 32 infants were recorded on video from minute 2 to minute 10. Infant- and maternal- influencing factors were noted and videos analyzed using Interact (Version 7.1, Mangold International, Arnstorf, Germany). According to our results, 99 of 102 newborns (gestational age, 33 to 42 weeks) performed EO or TT during the first 15 minutes. Preterm and infants with lower Apgar scores and infants born under general anesthesia showed less EO. Infants of smoking mothers, newborns admitted to special care, and infants with lower umbilical artery pH had significantly fewer TT episodes. Within a "normal" population of newborns of > 37 weeks at delivery (n = 57), 97% showed EO and 95% showed TT. In the filmed 32 newborns, infants began EO at 2:40 and TT at 2:34 minutes of life on average. Crying had no influence, but suctioning/intervention reduced EO frequency. In conclusion, EO and TT are occurring regularly during neonatal adaptation. TT seems to be an inborn automatic behavior; numerous occurrences of EO argue for neurological well-being. Both facial actions may initiate maternal-infant attachment. 相似文献
32.
Dieter Niederacher Frauke Picard Claudia van Roeyen Han-Xiang An Hans Georg Bender Matthias Wilhelm Beckmann 《Genes, chromosomes & cancer》1997,18(3):181-192
Loss of heterozygosity (LOH) on chromosome 17 is a frequent genetic alteration in breast cancer. To assess whether the location of potential tumor suppressor genes is compatible with the LOH pattern in individual tumors, we analyzed allele loss on chromosome 17 in 121 invasive ductal breast carcinomas and 16 benign breast tumors with 14 polymorphic microsatellite markers (4 on 17p and 10 on 17q). Fluorescent polymerase chain reaction (PCR) for typing microsatellites coupled with DNA fragment analysis in an automated DNA sequencer was applied. Frequencies of LOH varied from 29.4% (D17S1322) to 57.4% (TP53-Alu). No LOH could be detected in benign breast tumors. In 54 tumors the deletion patterns were consistent with the complete loss of 17p (n = 28), 17q (n = 9), or the whole chromosome 17 (n = 17). Five smallest regions of overlap (SROs) were identified in tumors with interstitial deletion patterns. On 17p, two foci were detected affecting the TP53 locus and the hypermethylated in cancer I (HICI) region (17p13.3). On 17q, SROI was localized between markers THRAI and D17S855, centromeric to the breast/ovarian cancer gene BRCAI; SRO2 was flanked by markers AFM234 and NMEI, and SRO3 was centered between markers MPO and GH. Associations between LOH and histopathological characteristics were determined. Significant correlations were found between higher grade and loss of the TP53 gene (marker TP53, P = 0.019), loss of the BRCAI region (P < 0.009), LOH of marker AFM155 (P = 0.003) and marker NMEI (P = 0.026). For positive estrogen receptor status, only LOH of the THRAI marker correlated significantly, whereas highly significant correlations were determined between positive progesterone receptor and markers centromeric to the BRCAI region D17S250 (P = 0.00002), THRAI (P = 0.0006), and the intragenic BRCAI markers [D17S1322 (P = 0.021), D17S855 (P = 0.029)]. Results presented in this study identify five independent regions of chromosome 17 which are likely to contain potential tumor suppressor genes involved in the carcinogenesis of sporadic breast cancer. Genes Chromosom. Cancer 18:181–192, 1997. © 1997 Wiley-Liss, Inc. 相似文献
33.
Frauke Nees Sabine Vollst?dt-Klein Mira Fauth-Bühler Sabina Steiner Karl Mann Luise Poustka Tobias Banaschewski Christian Büchel Patricia J. Conrod Hugh Garavan Andreas Heinz Bernd Ittermann Eric Artiges Tomas Paus Zdenka Pausova Marcella Rietschel Michael N. Smolka Maren Struve Eva Loth Gunter Schumann Herta Flor 《Experimental brain research. Experimentelle Hirnforschung. Expérimentation cérébrale》2012,223(3):429-439
Adolescence is a transition period that is assumed to be characterized by increased sensitivity to reward. While there is growing research on reward processing in adolescents, investigations into the engagement of brain regions under different reward-related conditions in one sample of healthy adolescents, especially in a target age group, are missing. We aimed to identify brain regions preferentially activated in a reaction time task (monetary incentive delay (MID) task) and a simple guessing task (SGT) in a sample of 14-year-old adolescents (N?=?54) using two commonly used reward paradigms. Functional magnetic resonance imaging was employed during the MID with big versus small versus no win conditions and the SGT with big versus small win and big versus small loss conditions. Analyses focused on changes in blood oxygen level?Cdependent contrasts during reward and punishment processing in anticipation and feedback phases. We found clear magnitude-sensitive response in reward-related brain regions such as the ventral striatum during anticipation in the MID task, but not in the SGT. This was also true for reaction times. The feedback phase showed clear reward-related, but magnitude-independent, response patterns, for example in the anterior cingulate cortex, in both tasks. Our findings highlight neural and behavioral response patterns engaged in two different reward paradigms in one sample of 14-year-old healthy adolescents and might be important for reference in future studies investigating reward and punishment processing in a target age group. 相似文献
34.
Sahiner B Chan HP Roubidoux MA Hadjiiski LM Helvie MA Paramagul C Bailey J Nees AV Blane C 《Radiology》2007,242(3):716-724
PURPOSE: To retrospectively investigate the effect of using a custom-designed computer classifier on radiologists' sensitivity and specificity for discriminating malignant masses from benign masses on three-dimensional (3D) volumetric ultrasonographic (US) images, with histologic analysis serving as the reference standard. MATERIALS AND METHODS: Informed consent and institutional review board approval were obtained. Our data set contained 3D US volumetric images obtained in 101 women (average age, 51 years; age range, 25-86 years) with 101 biopsy-proved breast masses (45 benign, 56 malignant). A computer algorithm was designed to automatically delineate mass boundaries and extract features on the basis of segmented mass shapes and margins. A computer classifier was used to merge features into a malignancy score. Five experienced radiologists participated as readers. Each radiologist read cases first without computer-aided diagnosis (CAD) and immediately thereafter with CAD. Observers' malignancy rating data were analyzed with the receiver operating characteristic (ROC) curve. RESULTS: Without CAD, the five radiologists had an average area under the ROC curve (A(z)) of 0.83 (range, 0.81-0.87). With CAD, the average A(z) increased significantly (P = .006) to 0.90 (range, 0.86-0.93). When a 2% likelihood of malignancy was used as the threshold for biopsy recommendation, the average sensitivity of radiologists increased from 96% to 98% with CAD, while the average specificity for this data set decreased from 22% to 19%. If a biopsy recommendation threshold could be chosen such that sensitivity would be maintained at 96%, specificity would increase to 45% with CAD. CONCLUSION: Use of a computer algorithm may improve radiologists' accuracy in distinguishing malignant from benign breast masses on 3D US volumetric images. 相似文献
35.
The use of antiepileptic drugs (AED), their primary indication, comorbid conditions, and concomitant medications were collected from 565 nursing homes (NH) residents of six NH located around the city of Mainz, Germany representing 5.05% of all NH residents in the area. Data were collected from the electronic pharmacy files and by reviewing all available medical records. Average age was 82.2 +/- 2.4 years, 85.5% were women. Of 565 NH residents 28 (4.96%) received AED therapy, of which in 17 (63%) AED were prescribed for a seizure-related diagnosis. In 76.5% seizure types were unspecified and a distinction in focal and generalized epilepsy was made in only 23.5% of patients. Three patients never had epileptic seizures and in four residents the reason for AED use was unclear. AEDs most frequently prescribed were carbamazepine (37.1%), valproic acid (25.9%), and phenytoin (14.8%). Five patients received benzodiazepines (18.5%), newer generation AED were used in only four (14.8%) cases. Residents on average took n = 5.6 +/- 3.3 other drugs. Opportunities exist for health care professionals to improve the medical management of nursing facility residents receiving AEDs. 相似文献
36.
PURPOSE: Perioral reflex myoclonias (PORM) are obvious, frequent, but often unobserved focal seizures in different epileptic syndromes and the leading seizure type in reading epilepsy. PORMs remain often undiagnosed because the patients are not aware that these are epileptic seizures and fail to report them. Their semiology is not fundamentally different in various epileptic syndromes. METHODS: We studied the frequency of PORM in patients with juvenile myoclonic epilepsy (JME) compared with patients with focal epilepsies. Twenty-five patients with JME were investigated with a standardized neuropsychological test program and compared with 25 matched patients with focal epilepsies. Statistical significance was calculated by using Fisher's exact test. RESULTS: We found significant differences between the groups regarding both frequency of PORM and activation of epileptic discharges. These observations seem to indicate that PORM, like praxis-induced seizures, are typical traits in JME. CONCLUSIONS: PORM are more frequent in JME compared with focal epilepsies. The distinction between focal and generalized epileptic ictogenesis may be less clear than is traditionally believed. 相似文献
37.
38.
Ischebeck A Indefrey P Usui N Nose I Hellwig F Taira M 《Journal of cognitive neuroscience》2004,16(5):727-741
In order to separate the cognitive processes associated with phonological encoding and the use of a visual word form lexicon in reading, it is desirable to compare the processing of words presented in a visually familiar form with words in a visually unfamiliar form. Japanese Kana orthography offers this possibility. Two phonologically equivalent but visually dissimilar syllabaries allow the writing of, for example, foreign loanwords in two ways, only one of which is visually familiar. Familiarly written words, unfamiliarly written words, and pseudowords were presented in both Kana syllabaries (yielding six conditions in total) to participants during an fMRI measurement with a silent articulation task (Experiment 1) and a phonological lexical decision task (Experiment 2) using an event-related design. Consistent over two experimental tasks, the three different stimulus types (familiar, unfamiliar, and pseudoword) were found to activate selectively different brain regions previously associated with phonological encoding and word retrieval or meaning. Compatible with the predictions of the dual-route model for reading, pseudowords and visually unfamiliar words, which have to be read using phonological assembly, caused an increase in brain activity in left inferior frontal regions (BA 44/47), as compared to visually familiar words. Visually familiar and unfamiliar words were found to activate a range of areas associated with lexico-semantic processing more strongly than pseudowords, such as the left and right temporo-parietal region (BA 39/40), a region in the left middle/inferior temporal gyrus (BA 20/21), and the posterior cingulate (BA 31). 相似文献
39.
Helmut Niederhofer Frauke Menzel Karl Gbel Brigitte Hackenberg Rainer Richter Maria Hildegard Walter Christian Gross Markus Huber Roger Pycha Hans-Jürgen Menzel 《Neuropsychiatric Disease and Treatment》2008,4(4):701-705
Attention deficit hyperactivity disorder (ADHD) is one of the most prevalent childhood-onset psychiatric syndromes affecting 5%–10% of school-age children worldwide. Distortions in the catecholaminergic system seem to be responsible for this condition. Within this system there are several candidate genes, the dopamine receptor D4 (DRD4) and the dopamine transporter 1 (DAT1), with common polymorphism which might be associated with ADHD. We performed a family based association study with 36 trios and 19 parent proband pairs. All diagnoses were confirmed by the “Hypescheme” diagnostic computer program. In this study we did not observe an association of ADHD with DRD4 and DAT1 polymorphism neither by the haplotype relative risk (HRR) method nor by the transmission disequilibrium test (TdT) method. The odds ratio for the DRD4 7-allele was 1.01 and 0.94 for both statistical tests, respectively, and the respective odds ratio for the DAT1 6-allele were 0.91 and 0.88. 相似文献
40.
Margarita Maltseva;Felix Rosenow;Susanne Schubert-Bast;Silke Flege;Markus Wolff;Sarah von Spiczak;Regina Trollmann;Steffen Syrbe;Susanne Ruf;Tilman Polster;Bernd A. Neubauer;Thomas Mayer;Julia Jacobs;Gerhard Kurlemann;Gerhard Kluger;Kerstin A. Klotz;Matthias Kieslich;Lara Kay;Frauke Hornemann;Ulrich Bettendorf;Astrid Bertsche;Thomas Bast;Adam Strzelczyk; 《Epilepsia》2024,65(1):115-126
The aim was to investigate the monitoring, interventions, and occurrence of critical, potentially life-threatening incidents in patients with Dravet syndrome (DS) and caregivers’ knowledge about sudden unexpected death in epilepsy (SUDEP). 相似文献