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51.
Bardia Vadiati Saberi Negar Khosravifard Kowsar Nooshmand Zahra Dalili Kajan Mohammad Ebrahim Ghaffari 《Dento maxillo facial radiology》2021,50(6)
Objectives:The effect of metallic objects on the fractal dimension (FD), bone area fraction (BAF) and gray scale values (GSVs) of cone-beam CT (CBCT) images was assessed. Also, FD, BAF and GSV were compared among CBCT, digital periapical and panoramic radiographies.Methods:Digital periapical and panoramic radiographs were acquired from six blocks of bovine rib. Additionally, different arrangements of titanium implants and intracanal metallic posts were created in the bone blocks and CBCT scans were taken from the different implant-root arrangements. The three radiographical modalities were compared by analysis of variance. Pairwise comparisons between the modalities were performed by the Tukey test (significance level set at 0.05).Results:Different root-implant arrangements in the CBCT images revealed no significant differences in the FD (p = 0.920), BAF and GSV values (p = 0.623). FD differed significantly among the three modalities (p < 0.001). Significant differences were found between CBCT and each of the periapical and panoramic techniques (p < 0.001), while no remarkable differences were observed in the FD of the periapical and panoramic images (p = 0.294). BAF and GSV showed significantly different results among the three radiographical techniques (p < 0.001). The difference was remarkable between CBCT and periapical (p < 0.001), CBCT and panoramic (p < 0.001) and periapical and panoramic (p = 0.008).Conclusion:Presence of titanium implants and intracanal posts does not produce different results in the fractal analysis (FA) of the CBCT images. The trabecular bone pattern is best assessed by FA of the periapical radiographs followed by the panoramic and CBCT techniques, respectively. 相似文献
52.
The effect of bonding agents on the microleakage of sealant following contamination with saliva 总被引:1,自引:0,他引:1
Askarizadeh N Norouzi N Nemati S 《Journal of the Indian Society of Pedodontics and Preventive Dentistry》2008,26(2):64-66
Aims : An issue of concern in dentistry is the inadequacy of adhesion and proper sealing following restoration of a tooth, which can lead to marginal leakage. The aim of this study was to evaluate the effect of a bonding agent on the microleakage of a sealant material following contamination with saliva. Materials and Methods : In this experimental research, 48 sound premolars were divided into two groups. The first group received sealant without bonding and the other group was given sealant with bonding. After prophylaxis, the occlusal surfaces were etched with 37% phosphoric acid gel and the teeth were then placed in fresh human saliva for l0 s. Following this, in the first group fissure sealant (Kerr) was applied directly and cured; for the second group sealant was placed and cured after bonding (Single Bond; 3M). All samples were thermocycled (500 cycles; between 5 degrees C and 55 degrees C; dwell time of 30 s). Silver nitrate was used as the leakage tracer. The teeth were sectioned. Microleakage evaluation was made by stereomicroscope at 40x magnification and the results were evaluated with the Mann-Whitney U test. Results : In the group that received sealant without bonding extensive microleakage was seen; placement of sealant with bonding significantly reduced microleakage. Conclusion : In the presence of contamination with saliva, use of bonding under the fissure sealant can reduce microleakage. 相似文献
53.
Germinal matrix-intraventricular hemorrhage (IVH) is the most common variety of neonatal intracranial hemorrhage and is characteristics of the premature infant. The importance of the lesion relates not only to its high incidence but to their attendant complications (IC: hydrocephalus). Brain sonography is the procedure of choice in diagnosis of germinal matrix- intraventricular hemorrhage and hydrocephalus. In this study we have used brain sonography for detection of intraventricular hemorrhage and post hemorrhagic hydrocephalus and their incidences. The studied population was consisted of premature neonate (birth weight equal or less than 1500 g and gestational age equal or less than 37 weeks) who admitted in Mofid Hospital NICU (Tehran, Iran) during a one year period. For all neonate (including criteria) brain sonography in first week of life was done and in presence of IVH, serial Brain sonography was done weekly for detection of hydrocephalus. A total of 57 neonate entered the study. Intraventricular-germinal matrix hemorrhage was seen in 64.4% (35 patients). Forty percent of patients with intraventricular-germinal matrix hemorrhage had grade I, 11% grade II, 25.7% grade III, 2.8% grade VI. Hydrocephalus was detected in 20 percent of patients who had intraventricular-germinal matrix hemorrhage. That incidence of IVH in our study in comparison with other area and situation is higher. Hydrocephaly had direct relation with severity of IVH. This shows that with control of risk factor of IVH, we can control Post hemorrhagic hydrocephalus. 相似文献
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56.
Green JS Singh J Cheung M Adler FC Ashouri N 《The Pediatric infectious disease journal》2011,30(2):163-165
Murine typhus is typically a mild febrile illness caused by Rickettsia typhi, generally con?ned to Texas and Southern California. Clinicians should consider early treatment with doxycycline when presented with a child having protracted fever, rash, and headache.We present 5 pediatric cases and a literature review highlighting the changing epidemiology and diagnostic dif?culty of typhus. 相似文献
57.
Negar G. Knowles Smita Patel Ella A. Kazerooni 《The international journal of cardiovascular imaging》2009,25(Z2):255-265
Coronary CT angiography (CCTA) is emerging as a powerful tool for the diagnosis and characterization of coronary artery disease.
In the emergency department (ED) setting, the high negative predictive value of CCTA has been shown to reduce the length of
stay and the cost of care in the evaluation of patients at low and intermediate risk for an acute coronary syndrome (ACS).
In addition, CCTA and triple-rule-out protocol CT examinations which simultaneously evaluate the coronary arteries, aorta
and pulmonary arteries, have the potential to diagnose not only significant atherosclerotic coronary artery disease (CAD)
and coronary artery anomalies, but noncoronary etiologies of chest pain, including pulmonary embolism, aortic dissection,
infection, pleural and pericardial disease. Caution has been raised about the widespread use of CCTA in this setting, particularly
given the prevalence of repeat ED visits for chest pain, due to the radiation exposure associated with retrospectively-gated
CCTA. However, the recent development of prospectively-triggered coronary artery CTA makes the ED evaluation possible with
a substantially lower radiation exposure to the patient. Although most studies of CCTA to date are performed with retrospective
ECG gating, early reports on prospectively triggered CCTA demonstrate equivalent image quality and accuracy when compared
to studies acquired with retrospective ECG gating. 相似文献
58.
Alireza Foroumadi Saeed Emami Saeed Rajabalian Marziyeh Badinloo Negar Mohammadhosseini Abbas Shafiee 《Biomedicine & Pharmacotherapy》2009
As part of a continuing search for new potential anticancer candidates in the piperazinyl quinolone series, the cytotoxicity evaluation of new N-substituted piperazinyl quinolones was of our interest. The growth inhibitory activities of 12 new compounds, namely N-[2-(5-chlorothiophen-2-yl)-2-oxoethyl] and N-[2-(5-chlorothiophen-2-yl)-2-oxyiminoethyl] piperazinyl quinolones 1–12 were determined against six cancer cell lines using MTT colorimetric assay. Preliminary screening showed that most of the new N-[2-(5-chlorothiophen-2-yl)ethyl]piperazinyl quinolones 4–12 containing (un)substituted oxime moiety showed significant cytotoxic activity and the modification of functionality on ethyl spacer produced a relatively minor change of activity. Thus, in the piperazinyl quinolone series, cytotoxic activity can be positively modulated through the introduction of 2-(5-chlorothiophen-2-yl)ethyl residue on the piperazine ring. The results revealed that the introduction of 2-(5-chlorothiophen-2-yl)ethyl moiety on the piperazine ring of quinolone antibacterials (ciprofloxacin, norfloxacin and enoxacin) changes the biological profile of piperazinyl quinolones from antibacterials to cytotoxic agents. 相似文献
59.
Negar Fani Bekh Bradley-Davino Kerry J. Ressler Erin B. McClure-Tone 《Cognitive therapy and research》2011,35(1):57-67
Childhood maltreatment increases risk for Posttraumatic Stress Disorder (PTSD). Maladaptive patterns of attention to emotionally salient stimuli warrant examination as possible mediators of the relationship between childhood maltreatment and PTSD. It remains unclear whether persistent attentional biases are differentially apparent in adults who were maltreated as children and either did or did not develop later PTSD symptomatology. The present study examined associations among attention bias, childhood maltreatment, and PTSD in adults. We tested the hypothesis that attentional bias for emotional cues (angry faces, happy faces), measured using the Dot Probe Task, would significantly mediate associations between childhood maltreatment and adult PTSD symptoms in a sample of 161 adults with and without childhood maltreatment histories and/or current PTSD symptoms. We found that attention bias toward happy faces partially mediated the relationship between childhood maltreatment and PTSD avoidance and numbing symptoms. 相似文献
60.
Background: Whether psychological resilience correlates with neurocognitive performance is largely unknown. Therefore, we assessed association between neurocognitive performance and resilience in individuals with a history of childhood abuse or trauma exposure. Methods: In this cross‐sectional study of 226 highly traumatized civilians, we assessed neurocognitive performance, history of childhood abuse and other trauma exposure, and current depressive and PTSD symptoms. Resilience was defined as having ≥1 trauma and no current depressive or PTSD symptoms; non‐resilience as having ≥1 trauma and current moderate/severe depressive or PTSD symptoms. Results: The non‐resilient group had a higher percentage of unemployment (P=.006) and previous suicide attempts (P<.0001) than the resilient group. Both groups had comparable education and performance on verbal reasoning, nonverbal reasoning, and verbal memory. However, the resilient group performed better on nonverbal memory (P=.016) with an effect size of .35. Additionally, more severe childhood abuse or other trauma exposure was significantly associated with non‐resilience. Better nonverbal memory was significantly associated with resilience even after adjusting for severity of childhood abuse, other trauma exposure, sex, and race using multiple logistic regression (adjusted OR=1.2; P=.017). Conclusions: We examined resilience as absence of psychopathology despite trauma exposure in a highly traumatized, low socioeconomic, urban population. Resilience was significantly associated with better nonverbal memory, a measure of ability to code, store, and visually recognize concrete and abstract pictorial stimuli. Nonverbal memory may be a proxy for emotional learning, which is often dysregulated in stress‐related psychopathology, and may contribute to our understanding of resilience. Depression and Anxiety, 2010. © 2010 Wiley‐Liss, Inc. 相似文献