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51.
Effects of sevoflurane on QT dispersion and heart rate variability   总被引:1,自引:0,他引:1  
The purpose of this study was to use estimates of corrected QT dispersion (QTcd) and heart rate variability (HRV) to assess the effects of sevoflurane, an inhalation agent used frequently in clinical practice, on autonomic cardiac function. This study was conducted prospectively and in a blind manner on 20 women between 38 and 51 y of age who were classified as American Society of Anesthesiologists stage I–II and whose treatment required total abdominal hysterectomy. Electrocardiograms were recorded by 12-lead Holter monitor for 5 min before sevoflurane induction and again for 5 min at 10 min after tracheal intubation. Data on the first recording were considered as baseline; those on the second recording were viewed as final data. The study was terminated at this point, and surgery was allowed to proceed. QTcd and HRV values were assessed by a cardiologist, who was blinded to all data. All parameters were expressed as a mean value ± standard deviation. Wilcoxon’s test was used to compare baseline and final data. Statistical significance was considered asP< .05. No significant changes were observed between baseline and final QTcd values and between low and high-frequency components (LF and HF) of HRV; nor were changes seen in the LF/HF ratio. With the patient under sevoflurane/nitrous oxide anesthesia, no significant changes were detected in QTcd, LF, and HF values, and in the LF/HF ratio, whereas a significant increase (P=.001) was seen in standard deviation of the R-R interval, which was used as a measure of cardiac autonomic tone.  相似文献   
52.
In the present work, we isolated two bioactive diterpenoids, horminone and 7-O-acetylhorminone and developed a micellar electrokinetic chromatography (MEKC) method for the simultaneous quantitative analysis of them in Turkish Salvia species. The optimal separation electrolyte was 50 mmol/L SDS and 25% methanol at pH 11.5. The limits of detection (S/N = 3) were 3.269 and 4.518 μg/mL for horminone and 7-O-acetylhorminone, respectively. The method has been applied successfully to analyze these two components in Salvia chionantha and Salvia kronenburgii acetone extracts.  相似文献   
53.
Bayar A  Sarikaya S  Keser S  Ozdolap S  Tuncay I  Ege A 《The Knee》2008,15(5):373-377
Bone mineral density (BMD) loss is one of the secondary problems occurring in knee joint after injury of anterior cruciate ligament (ACL). The effect of this injury on BMDs of specific regions is not clear. The aim of this study was to investigate BMD changes in unreconstructed ACL-deficient knees with subregion analysis of dual energy X-ray absorptiometry (DEXA). Precision and reliability studies of DEXA revealed that two region of interests (ROI) in medial condyle, two ROIs in lateral femoral condyle (LFC) and one ROI in medial tibial plateau (MTP) in anteroposterior (AP) DXA view and one ROI for each of distal femur, proximal tibia and patella in lateral view had high reproducibility and reliability. Thirty-two patients with complete ACL ruptures were collected for the study and uninjured sides served as the control. All the patients were male with a mean age of 30 years. Mean duration of ACL rupture was 24 months. There were significant BMD losses in both ROIs of LFC and ROI of MTP in AP view and all three ROIs of lateral view. Greatest BMD losses in AP and lateral views were at MTP and patella respectively. There was a significant association between patellar BMD loss and duration after trauma. Bone bruises in lateral condyle might be the cause of selective involvement of LFC. Periarticular bone mineral loss in ACL-deficient knees has a predilection for the specified region of interest rather than uniform periarticular loss. This may be important for graft fixation or a factor in tunnel enlargement.  相似文献   
54.
55.
AimThis study was conducted to determine the effect of the illness management and recovery program in patients with schizophrenia.MethodsThis study was conducted using a pretest, posttest and follow up experimental design with randomized controlled. The sample of this study consisted of patients with schizophrenia (n = 50). The patients were assigned to intervention (n = 25) and control (n = 25) groups using the randomisation method. The intervention group consisted of 10 modules and 20 sessions of Illness Management and Recovery Program, while in the control group, a face-to-face interview. Data were collected by the Illness Management and Recovery Scale-Patient Form (IMRS-P) and Social Functioning Scale-Patient Form (SFS-P).ResultsThere were significant differences in posttest and 1-month follow-up IMRS-P points between the intervention and control groups. There was no significant difference in post-test and 1-month follow-up SFS-P total points between the intervention and control groups. There were only significant differences for the pro-social activities' subscale of SFS-P.ConclusionThe Illness Management and Recovery Program have a positive effect on illness management and social functionality in patients with schizophrenia. In the light of this study, it was suggested that this structured program should be used by mental health and psychiatric nurses.  相似文献   
56.
Intraparenchymal location of schwannomas in the central nervous system (CNS) is rare. Occasional cases involving the cerebrum, cerebellum, brain stem, and spinal cord have been reported. We report here an additional case of thoracic intramedullary schwannoma in a 42 year old woman. The literature concerning intraparenchymal schwannomas in the CNS is reviewed and discussed.  相似文献   
57.
Our aim was to show that microcomputed tomography is a useful tool for acquiring high-resolution three-dimensional tomographic images to assess bone healing, the interface with materials, and the biocompatibility of bone substitutes. Acquired images can be used for non-invasive quantitative morphometric analysis of regenerating bone, leaving the option for conventional histology to be an adjunct used at defined intervals. The temporal characterisation of the mineralisation of bone potentially has a critical role in the understanding of the dynamics of mineralisation of healing bone. This has applications both for degradable and bioactive materials and for pharmaceutical products that act on bone. Formal validation of this promising new technique will be a critical part of continuing studies.  相似文献   
58.
With a view to understanding the structure-property relation of a silicone-based soft lining denture material after polymerization, its chemical composition and viscoelastic properties were investigated. Chemical compositions of the cured and uncured polymers of a commercial silicone permanent soft liner were determined by infrared spectroscopic analysis, nuclear magnetic resonance (NMR), and X-ray photoelectron spectroscopy. Dynamic mechanical analysis (DMA) method was used to investigate the viscoelastic behavior of the cured polymer of liner. Spectroscopic analysis showed that the main component of soft liner was vinyl-terminated poly(dimethylsiloxane), and the adhesive was 3-methacryloxypropyltrimethoxy silane. NMR results revealed that other components included benzoyl peroxide as initiator for polymerization and also silicilic acid. Surface analysis by XPS provided interesting insights about the nature of adhesive bonding, as well as diffusion of silicilic acid through the matrix of the processed material and leaching-out. DMA results showed a two-phase character, and that the cured polymer was highly elastic.  相似文献   
59.
We prepared several series of poly(isobutylene) (PIB) gels starting from butyl rubber in dilute toluene solutions using sulfur monochloride as a crosslinking agent. Solution and suspension‐crosslinking techniques were used for the preparation of PIB gels in the form of rods, membranes, and beads in the size range of 1 to 3 mm. The gels were subjected to dynamic and equilibrium swelling measurements in toluene and cyclohexane as well as to the elasticity tests. Depending on the amounts of sulfur monochloride and butyl rubber in the crosslinking solution, PIB gels with different swelling capacities and elastic moduli were synthesized. The swelling ratio of the gels first increased rapidly with increasing swelling time but then decreased until an equilibrium was obtained. This unusual swelling behavior was accompanied with an increase of the elastic moduli of the gels during the swelling process. The results were explained with the post‐crosslinking reactions taking place during the swelling process of PIB gels. By using the theory of equilibrium swelling, the number of segments in the network chains and the polymer‐solvent interaction parameters were calculated for PIB gels prepared under various reaction conditions.  相似文献   
60.
Background/aim It is known that the presence of fragmented QRS (fQRS) on electrocardiography (ECG) is associated with cardiovascular events. The aim of this study was the evaluation of fQRS formation and its relationship with the left ventricular hypertrophy (LVH) parameters in acromegaly patients. Materials and methods In total, 47 previously diagnosed with non-hypertensive acromegaly patients and 48 control subjects were included in the study. ECG and transthoracic echocardiography (TTE) were performed for each participant. Acromegaly patients were divided into two groups according to the fQRS formation on the ECG. Left ventricular wall thicknesses, and left atrial diameter (LAD), left ventricular mass (LVM), left ventricular mass index (LVMi), and relative wall thickness (RWT) were obtained. Results In control group 5 (10.4%) and in acromegaly group 17 (36.2%) patients had fQRS on ECG (p = 0.003). LAD [36.0 (34.0–38.0) vs. 38.0 (35.0–41.0) mm, p < 0.001], LVM [155.27 ± 27.00 vs. 173.0 (153.0–235.0) g, p < 0.001], LVMi [83.12 ± 13.19 vs. 92.0 (83.0–118.0) g/m², p < 0.001] and RWT [0.39 ± 0.03 vs. 0.43 (0.41–0.45), p = 0.001] were significantly higher in patients with acromegaly. Disease duration was significantly higher (11.59 ± 1.3 vs. 8.2 ± 1.8 years, p < 0.001) in the fQRS (+) group. LAD [41.0 (39.0–42.5) vs. 37.0 (34.7–38.0) mm, p < 0.001], LVM [219.0 (160.5–254.5) vs. 164.0 (153.0–188.0) g, p = 0.017], LVMi [117.0 (92.5–128.5) vs. 86.0 (82.0–100.2) g/m², p = 0.013] and RWT [0.44 (0.42–0.49) vs. 0.43 (0.40–0.44), p = 0.037] were significantly higher in fQSR (+) acromegaly patients. In multivariate logistic regression analysis, disease duration (odds ratio: 10.05, 95% CI: 1.099–92.012, p = 0.041) and LAD (odds ratio: 2.19, 95% CI: 1.030–4.660, p = 0.042) were found to be the independent predictors of fQRS formation.Conclusion The results of our study revealed that fQRS (+) acromegaly patients had increased LVH parameters compared to fQRS (-) patients.  相似文献   
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