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21.
A series of conformationally controlled 2-PAM derivatives were prepared from 2-acetylpyridine and 2,3-pyrido[b]cycloalkenones in two steps and their reactivities towards parathion poisoned AChE were evaluated. The most planar 2,3-pyrido[b]cyclohexanone oxime methiodide showed an activity comparable to 2-PAM implying E-syn is that the most active conformation of 2-PAM in the biological system.  相似文献   
22.
Our goal was to investigate whether three-dimensional (3D) double inversion recovery (DIR) images can show alterations of gray matter volume (GMV) between Alzheimer’s disease (AD) patients and nondemented controls and to compare alterations of GMV between groups using DIR images and those using 3D T1-weighted (T1W) images. We included 25 subjects with mild or probable AD, 25 subjects with amnestic mild cognitive impairment (MCI), and 25 elderly cognitively normal (CN) subjects. Group differences in GMV among CN, MCI, and AD patients were tested by voxel-wise, one-way ANOVA. Additional region-of-interest-based comparisons of GMV differences among the three groups for DIR and T1WI were performed using ANCOVA. Finally, ROC curve analysis was performed. In the AD group compared with the CN and MCI groups, GMV was decreased in both DIR and T1W images. However, the areas showing GMV loss were larger in DIR images compared to those in T1W images. Amygdala had the highest area under curve value for both DIR and T1W images. DIR images were sensitive for identifying GMV loss in patients with AD compared with MCI and CN subjects and areas showing GMV loss identified with DIR were extended to more brain areas than those identified with T1W. With DIR, amygdala GMV is the most sensitive in differentiating between subject groups.  相似文献   
23.
ObjectiveThe purpose of this study was to evaluate long-term follow-up radiologic/clinical outcomes of patients who underwent anterior cervical discectomy and inter-body fusion (ACDF) with stand-alone cages (SAC) in a single academic institution.MethodsTotal 99 patients who underwent ACDF with SAC between February 2004 and December 2012 were evaluated retrospectively. A total of 131 segments were enrolled in this study. Basic demographic information, radiographic [segmental subsidence rate, fusion rate, C2–7 global angle, and segmental angle changes)/clinical outcomes (by Odom''s criteria and visual analog score (VAS)] and complications were evaluated to determine the long-term outcomes.ResultsThe majority were males (55 vs. 44) with average age of 53.2. Mean follow-up period was 62.9 months. The segmental subsidence rate was 53.4% and fusion rate was 73.3%. In the subsidence group, anterior intervertebral height (AIH) had more tendency of subsiding than middle or posterior intervertebral height (p=0.01). The segmental angle led kyphotic change related to the subsidence of the AIH. Adjacent segmental disease was occurred in 18 (18.2%) patients. Total 6 (6%) reoperations were performed at the index level. There was no statistical significance between clinical and radiological outcomes. But, overall long-term clinical outcome by Odom''s criteria was unsatisfactory (64.64%). The neck and arm VAS score were increased by over time.ConclusionLong-term outcomes of ACDF with SAC group were acceptable but not satisfactory. For optimal decision making, more additional comparative long-term outcome data is needed between ACDF with SAC and ACDF with plating.  相似文献   
24.
25.
The neuronal specificity of acupoints has not been entirely supported by the results of fMRI studies. The objective of this study was to investigate the neuronal specificity of an acupoint with electroacupuncture stimulation (EAS) using functional magnetic resonance imaging (fMRI). Functional MR imaging of the entire brain was performed in 12 normal healthy subjects during EAS of GB34 (Yanglingquan) and its sham point over the left leg in counter-balanced order. Anatomically, both GB34 and its sham point belong to the L5 spinal segment. EAS at the left GB34 specifically activated the right putamen, caudate body, claustrum, thalamus, cerebellum, as well as the left caudate body, ventral lateral thalamus, and cerebellum, all related to motor function. EAS at the sham point of the left GB34 specifically activated the right BA6, BA8, BA40, BA44, thalamus, as well as the left thalamus and cerebellum. Taken together, these findings suggest that EAS at an acupoint and its sham point, in the same spinal segment, induced specific cerebral response patterns. These findings support neuronal specificity of the acupoint studied. EAS at GB34 appears to be more related to motor function than EAS at its sham point, suggesting specificity of the GB34 acupoint. The results of this study provide neurobiological evidence for the existence of acupoint specificity, although further studies are necessary to better understand this phenomenon.  相似文献   
26.

Objective

The aim of this study was to evaluate the efficacy of endovascular therapy as a primary treatment for spinal dural arteriovenous fistula (DAVF).

Methods

The authors reviewed 18 patients with spinal DAVFs for whom endovascular therapy was considered as an initial treatment at a single institute between 1993 and 2006. NBCA embolization was considered the primary treatment of choice, with surgery reserved for patients in whom endovascular treatment failed.

Results

Surgery was performed as the primary treatment in one patient because the anterior spinal artery originated from the same arterial pedicle as the artery feeding the fistula. Embolization was used as the primary treatment modality in 17 patients, with an initial success rate of 82.4%. Two patients with incomplete embolization had to undergo surgery. One patient underwent multiple embolizations, which failed to completely occlude the fistula but relieved the patient''s symptoms. Spinal DAVF recurred in two patients (one collateral development and one recanalization) during the follow-up period. The collateral development was obliterated by repeated embolization, but the patient with recanalization refused further treatment. The overall clinical status improved in 15 patients (83.3%) during the follow-up period.

Conclusion

Endovascular therapy can be successfully used as a primary treatment for the majority of patients with spinal DAVFs. Although it is difficult to perform in some patients, endovascular embolization should be the primary treatment of choice for spinal DAVF.  相似文献   
27.

Objective

Total laminectomy (TL) is an effective surgical technique for the treatment of cervical ossification of the posterior longitudinal ligament (OPLL) along multiple levels. However, kyphosis and probable neurological deterioration have been frequently reported after laminectomy. We analyzed the changes in the cervical curvature after TL and subsequent changes in neurological status.

Methods

We retrospectively reviewed the records of 14 patients who underwent TL for the treatment of cervical OPLL between Jan. 1998 and Dec. 2003. TL was selected according to the previously determined criteria. The curvature of the cervical spine was visualized on a lateral cervical spine X-ray and measured using Ishihara''s Curvature Index (CI) before the operation and at the last follow-up examination. Perioperative neurological status was estimated using the modified Japanese Orthopedic Association score and the Improvement Rate (IR) at the same time as the images were evaluated.

Results

The mean age of the patients was 57 years, the male/female ratio was 10:4, and the mean follow-up period was 41 months. The mean number of OPLL was 4.9, and the mean number of operated levels was also 4.9. The CI decreased after TL (p=0.002), which was indicative of a kyphotic change. However, this kyphotic change showed no correlation with the length of the follow-up period, number of operated levels and preoperative CI. Neurological examination at the last follow-up showed an improved neurological status in all patients (p=0.001). There was no neurological deterioration in any case during the follow-up period. Moreover, there was no correlation between IR and the degree of kyphotic change. Postoperative complications, such as C5 radiculopathy and epidural bleeding, resolved spontaneously without neurological sequelae.

Conclusion

Kyphotic change was observed in all but one patient who underwent TL for the treatment of cervical OPLL. However, we did not find any contributing factors to kyphosis or evidence of postoperative neurological deterioration.  相似文献   
28.
PURPOSE: Most metacarpal fractures are stable and can be treated with nonsurgical stabilization. However, some metacarpal fractures are treated with open reduction and internal fixation because of an open fracture, instability, or multiple fractures. Newer plate designs have emerged that allow a shorter plate and screw construct. We sought to determine the relative strength of 3 different methods of metacarpal plating for unstable fractures. METHODS: We tested our hypothesis in a transverse metacarpal fracture model using fourth-generation, biomechanical testing grade composite sawbones (Sawbones; Pacific Research Laboratories, Vashon, WA). The metacarpals were divided into 3 groups of 15 bones. Group 1 was plated with a standard 6-hole, 2.3-mm plate with 6 nonlocking bicortical screws in standard AO fashion. Group 2 was plated with a 6-hole, double-row, 3-dimensional (3D) plate with 3 nonlocking screws on either side of the fracture aiming for convergence of the screws. Group 3 was plated with a 2.4-mm plate using 6 nonlocking screws and standard AO technique. The metacarpals were then tested to failure in cantilever bending mode. RESULTS: All constructs broke through the bone. No plate failure or screw pullout was seen. Group 1 had a load to failure of 264 N +/- 14. Group 2 had a load to failure of 302 N +/- 17. Group 3 had a load to failure of 274 N +/- 20. The load to failure was highest in group 2 (3D plate). All differences were statistically significant. CONCLUSIONS: All 3 methods produced a strong construct. The load to failure was highest in group 2 (3D plate). Double-row plates with converging screws provide adequate or superior strength of fixation when compared with standard plate constructs.  相似文献   
29.
30.
A 58‐year‐old woman complained of painless jaundice. The serology showed total bilirubin 10.6 mg/dL with direct bilirubin of 7.0 mg/dL. Abdominal computed tomography (CT) scan disclosed an abnormal arrangement of the abdominal viscera and dilation of the biliary tree. A nearly 1.4 cm‐sized periampullary mass was seen. These findings are compatible with situs ambiguous with polysplenia and were suggestive of a periampullary tumor. Due to her unusual anatomical features, the patient underwent an endoscopic retrograde cholangiopancreatography (ERCP) in the supine position instead of in the conventional prone position. ERCP showed that the common bile duct (CBD) diameter was increased to 20 mm. Microscopic findings of the biopsy specimen of papillary mass were compatible with an adenocarcinoma of the ampulla of Vater. The clinical stage was stage IA (T1N0M0). Eight days later, a papillectomy was carried out by endoscopic snare resection. Six months later, follow‐up studies, including ERCP, abdominal CT and 18‐fluorodeoxyglucose positron emission tomography (18‐FDG PET)‐CT scan, showed no evidence of recurrence. Although the success rate of supine position ERCP may be influenced by the extent of the intestinal malrotation and the position of the duodenum, we conclude that supine position ERCP can be carried out effectively in a patient with situs anomaly.  相似文献   
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