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991.
Contact transducers are a key element in experiments involving body sounds. The characteristics of these devices are often not known with accuracy. There are no standardized calibration setups or procedures for testing these sensors. This study investigated the characteristics of a new computer-controlled sound source phantom for testing sensors. Results suggested that sensors with different sizes require special phantom requirements. The effectiveness of certain approaches on increasing the spatial and spectral uniformity of the phantom surface signal was studied. Non-uniformities >20 dB were removable, which can be particularly helpful in comparing the characteristics of different size sensors more accurately. 相似文献
992.
Waldeck W Mueller G Wiessler M Tóth K Braun K 《International journal of medical sciences》2011,8(2):97-105
Fluorescent proteins (FPs) are established tools for new applications, not-restricted to the cell biological research. They could also be ideal in surgery enhancing the precision to differentiate between the target tissue and the surrounding healthy tissue. FPs like the KillerRed (KRED), used here, can be activated by excitation with visible day-light for emitting active electrons which produce reactive oxygen species (ROS) resulting in photokilling processes. It is a given that the extent of the KRED's cell toxicity depends on its subcellular localization. Evidences are documented that the nuclear lamina as well as especially the chromatin are critical targets for KRED-mediated ROS-based DNA damaging. Here we investigated the damaging effects of the KRED protein fused to the nuclear lamina and to the histone H2A DNA-binding protein. We detected a frequency of DNA strand breaks, dependent first on the illumination time, and second on the spatial distance between the localization at the chromatin and the site of ROS production. As a consequence we could identify defined DNA bands with 200, 400 and (600) bps as most prominent degradation products, presumably representing an internucleosomal DNA cleavage induced by KRED. These findings are not restricted to the detection of programmed cell death processes in the therapeutic field like PDT, but they can also contribute to a better understanding of the structure-function relations in the epigenomic world. 相似文献
993.
Cervical auscultation is a noninvasive technique for studying swallowing that was first used in the 1960s. The aim of our study was to use the numeric acoustic recording technique for analyzing swallowing sound signals in healthy subjects while they ingested a defined volume and consistency of a specific substance. Twenty males and ten females were included in the study and given 10 ml of a barium suspension to swallow. A microphone was placed on the skin overlying the lateral border of the trachea, directly under the inferior border of the cricoid, and connected to a computer. For each sound recording, the total duration of the sound (td), the number (n) of sound components (SC), the duration of each SC (c1, c2, c3,...), and the intervals (i1, i2,...) between the SCs were measured. For all the recordings, the mean durations of acoustic parameters (TDm, C1m, C2m, C3m, I1m, I2m) were calculated and compared by using Student’s t test. In the 20 male subjects, the mean acoustic parameters were calculated (MTDm, MC1m, MC2m, MC3m, MI1m, MI2m) and compared with the mean acoustic parameters (FTDm, FC1m, FC2m, FC3m, FI1m, FI2m) in the ten females by using a Wilcoxon nonparametric statistical test. We were able to interpret 80% of the recordings. The TDm was 710 ± 28 ms. Three main SCs were detected: C1m = 100 ± 56, C2m = 150 ± 90, C3m = 80 ± 54 ms; I1m = 100 ± 66, I2m = 190 ± 120 ms. No significant difference in these parameters was observed with respect to gender. This study enabled us to decompose the swallowing sounds into three main SCs and to quantify their normal durations. These results should prove useful for the assessment of sound variations in pathologic conditions. 相似文献
994.
PURPOSE: The goal of this paper is to review the imaging methods required for localizing nonpalpable Implanontrade mark. METHOD: Different localization methods for nonpalpable Implanon rods are summarized, and clinical guidance is provided as to how best to localize such implants. RESULTS: In the great majority of cases, optimal visualization of the single-rod Implanon rod is obtained with ultrasound using a high-resolution linear array transducer (10-15 MHz). An implant located just under the skin, under the fascia muscularis or one located deep in the muscle can most often be localized with ultrasound. In rare cases where ultrasound does not definitively locate the implant, magnetic resonance imaging is usually the next best choice. Measurements of serum etonogestrel levels may be necessary to confirm the presence or absence of the implant when it cannot be visualized by either of the two imaging methods. DISCUSSION: Close clinical coordination between women's health care providers and radiologists is required to minimize or prevent removal complications and to facilitate subsequent contraceptive management of the patient. 相似文献
995.
Beck R Rosenhouse G Mahagnah M Chow RM Cugell DW Gavriely N 《Annals of biomedical engineering》2005,33(10):1344-1351
We studied the mechanisms by which turbulent flow induces tracheal wall vibrations detected as tracheal breath sounds (TRBSs).
The effects of flow rate at transitional Reynold's numbers (1300–10,000) and gas density on spectral patterns of TRBSs in
eight normal subjects were measured. TRBSs were recorded with a contact sensor during air and heliox breathing at four flow
rates (1.0, 1.5, 2.0, and 2.5 l/s). We found that normalized TRBSs were proportional to flow to the 1.89 power during inspiration
and to the 1.59 power during expiration irrespective of gas density. The amplitude of TRBSs with heliox was lower than with
air by a factor of 0.33 ± 0.12 and 0.44 ± 0.16 during inspiration and expiration, respectively. The spectral resonance frequencies
were higher during heliox than air breathing by a factor of 1.75 ± 0.2—approximately the square root of the reciprocal of
the air/heliox wave propagation speed ratio. In conclusion, the flow-induced pressure fluctuations inside the trachea, which
cause tracheal wall vibrations, were detected as TRBSs consist of two components: (1) a dominant local turbulent eddy component
whose amplitude is proportional to the gas density and nonlinearly related to the flow; and (2) a propagating acoustic component
with resonances whose frequencies correspond to the length of the upper airway and to the free-field sound speed. Therefore,
TRBSs consist primarily of direct turbulent eddy pressure fluctuations that are perceived as sound during auscultation. 相似文献
996.
A behavioral paradigm to judge acute sodium salicylate-induced sound experience in rats: a new approach for an animal model on tinnitus 总被引:8,自引:0,他引:8
Behavioral conditioning studies on rats have been proven to be a valid animal model for the evaluation of acute and chronic phantom auditory experience (tinnitus). We developed an animal model for short-term, acute induced phantom auditory sensations in rats. Rats were trained in a conditioning chamber to actively access a liquid feeder whenever a constant white noise sound was present. During silence, no reward was given. Fulfilling the demands of animal protection laws for maximal avoidance of pain and fear, punitive paradigms were maximally reduced. After 15–17 learning sessions, all animals performed more accesses to the reward feeder during periods of sound than during periods of silence. Tinnitus was induced by the administration of sodium salicylate (350 mg/kg body weight) given 3 h before testing. The feeder access activity of a rat treated with salicylate was significantly increased during periods of silence, indicating a phantom auditory experience. The presumptive auditory experience was estimated to be comparable to a white noise sound of about 30 dB SPL rms. The activity increase was less pronounced for lower doses of sodium salicylate (150 mg/kg body weight) and was not found in animals trained on a dark–light paradigm, as expected. As the learning sessions of the operant conditioning were performed without pharmacological treatment, unintentional drug effects, for example, on learning and motivation of a rat were minimized in this behavioral paradigm. Furthermore, the behavioral changes reported here were shown to be a specific drug effect evoking a phantom auditory experience of a rat and cannot be explained by unspecific drug effects on motor activity, motivation, learning or hearing loss. The conditional paradigm is discussed in the context of its potential as a model for testing drugs that may have a therapeutic value in tinnitus research. 相似文献
997.
Klatzky RL Lippa Y Loomis JM Golledge RG 《Experimental brain research. Experimentelle Hirnforschung. Expérimentation cérébrale》2003,149(1):48-61
Participants standing at an origin learned the distance and azimuth of target objects that were specified by 3-D sound, spatial
language, or vision. We tested whether the ensuing target representations functioned equivalently across modalities for purposes
of spatial updating. In experiment 1, participants localized targets by pointing to each and verbalizing its distance, both
directly from the origin and at an indirect waypoint. In experiment 2, participants localized targets by walking to each directly
from the origin and via an indirect waypoint. Spatial updating bias was estimated by the spatial-coordinate difference between
indirect and direct localization; noise from updating was estimated by the difference in variability of localization. Learning
rate and noise favored vision over the two auditory modalities. For all modalities, bias during updating tended to move targets
forward, comparably so for three and five targets and for forward and rightward indirect-walking directions. Spatial language
produced additional updating bias and noise from updating. Although spatial representations formed from language afford updating,
they do not function entirely equivalently to those from intrinsically spatial modalities.
Electronic Publication 相似文献
998.
Park DJ Lee HJ Kim SG Jung HC Song IS Lee KU Choe KJ Yang HK 《Surgical endoscopy》2005,19(10):1358-1361
Background: Few reports are available on the use of intraoperative gastroscopy for gastric surgery.
Methods: The details of 33 patients (25 early gastric cancers and eight gastric submucosal tumors) who underwent intraoperative gastroscopy
from June 2003 to June 2004 were analyzed. The type of operation or resection margin was determined by evaluating both sides
of the stomach simultaneously by combined operative and gastroscopic methods.
Results: Preoperative endoscopic clipping was done preferentially for early gastric cancer. However, when precise localization was
needed, intraoperative gastroscopy was used. Curative gastric resection was possible in 25 early gastric cancer patients after
accurate lesion localization. Laparoscopic wedge resections of submucosal tumors were performed in seven patients without
stenosis by combined laparoscopic and gastroscopic methods.
Conclusions: Intraoperative gastroscopy can be used effectively during gastric surgery for early gastric cancer or submucosal tumors and
can be regarded as a modern stethoscope to gastric surgeons. 相似文献
999.
Summary Most current models of the neurophysiology of basic reading processes agree on a system involving two cortical streams: a ventral stream (occipital-temporal) used when accessing familiar words encoded in lexical memory, and a dorsal stream (occipital-parietal-frontal) used when phonetically decoding words (i.e., mapping sublexical spelling onto sounds). The models diverge, however, on the issue of whether the insular cortex is involved. The present fMRI study required participants to read aloud exception words (e.g., ‘one’, which must be read via lexical memory) and pseudohomophones (e.g., ‘wun’, which must be read via sublexical spelling to sound translation) to examine the processing streams as well as the insular cortex, and their relationship to lexical and sublexical reading processes. The present study supports the notion of independent ventral-lexical and dorsal-sublexical streams, and further suggests the insular cortex to be sensitive to phonological processing (particularly sublexical spelling-sound translation). These latter findings illuminate the nature of insular activity during reading, which must be explored further in future studies, and accounted for in models of the neurophysiology of reading. 相似文献
1000.
Cogan J Camus M Saucier JF Arsenault P Demers J 《Complementary therapies in clinical practice》2006,12(3):206-212
OBJECTIVE: Chart review to evaluate the effectiveness of a three-phase sound resonance technology therapy (SRTT) protocol for the treatment of fibromyalgia. RESULTS: Initial FIQ scores of 159 consecutive patients ranged from 24 to 80 (mean=58). After Phase 1, ( approximately 1 month into the protocol), FIQ scores had decreased on average by 26 points (n=128, 95% CI 23-30, p<.001). After phase 3 of the protocol 53 patients completed an FIQ questionnaire and the mean decrease in FIQ score was 38 points (95% CI 32-44, p=.004). CONCLUSIONS: This retrospective analysis suggests considerable and rapid relief of the symptoms of fibromyalgia following the use of the three-phase SRTT treatment protocol, which appears to be maintained over several years. Although these results are not conclusive they are remarkable as no other therapy reported in the scientific literature seems as efficacious for fibromyalgia. A follow-up study using an RCT design is warranted. 相似文献