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61.
62.
The unpredictable nature of bleeding and complications, and the highly variable nature of haemophilia A, necessitate that each patient be dealt with on an individual basis with treatment tailored to specific needs. Safety of treatment is paramount, and, due to concerns over viral safety, the use of recombinant factor VIII products has increased across Europe. Prophylaxis treatment has also increased, as recent studies have shown reductions in number of joint bleeds, fewer days lost from work, less need for surgery and fewer emergency hospital visits compared with on-demand regiments. Other factors that need to be considered include convenience for the patient, consistency of supply and cost. Consequently, management of haemophilia involves complex interrelationships between the patient, family and healthcare team.  相似文献   
63.
64.

Purpose

The effectiveness of imaging (including apparent diffusion coefficient [ADC] of diffusion-weighted magnetic resonance imaging [DWI]) and laboratory variables for predicting early tumor recurrence and overall survival after surgery in hepatocellular carcinoma (HCC) patients are analyzed.

Methods

The present study included 116 consecutive patients with HCC who underwent partial hepatectomy. Patients were classified into two groups: patients with and without early recurrence (<1 year). Preoperative imaging variables (tumor number, size, shape, capsule, ADC, and venous invasion) and laboratory variables were evaluated to predict early recurrence using univariate and multivariate analyses. Overall survival was calculated using the Kaplan–Meier method.

Results

Twenty patients (17 %) developed early recurrence after surgery. Multivariate logistic regression analysis showed that tumor ADC (p = 0.0002), aspartate aminotransferase (p = 0.0121), and serum prothrombin time activity percentage (p = 0.0082) were statistically significant for predicting early recurrence. The optimal ADC cutoff value for predicting early recurrence obtained from receiver operating characteristic analysis was ≤0.898 × 10?3 mm2/s. In patients with ADC ≤0.898 × 10?3 mm2/s, the 3- and 5-year survival rates (77 and 56 %, respectively) were significantly decreased compared with those in patients with ADC >0.898 × 10?3 mm2/s (97 and 97 %, respectively; p = 0.0015).

Conclusions

Low tumor ADC value by DWI was a risk factor for early postoperative HCC recurrence and was associated with lower patient survival rates.  相似文献   
65.

Purpose

To evaluate imaging characteristics of optic nerves by using magnetic resonance imaging, especially diffusion-weighted imaging (DWI) with apparent diffusion coefficient measurements in acute and chronic phases of optic neuritis (ON).

Materials and Methods

A retrospective study was conducted by using records of 14 patients with clinically suspected acute ON (15 nerves), 5 chronic ON (7 nerves), and 11 normal volunteers with no eye symptoms were used as controls. Magnetic resonance imaging was performed by a 1.5T scanner. Affected nerves were evaluated for sizes, signal characteristics on DWI and T2-weighted imaging (T2WI), contrast enhancement, and apparent diffusion coefficient values. Visually assessed characteristics were compared between the acute and chronic, whereas apparent diffusion coefficient values were assessed among acute ON, chronic ON, and the control groups by using the Fisher exact test and Mann-Whitney U test.

Results

There were significant differences in the diameter of the optic nerves, hyperintensity on DWI, and enhancement characteristics on post-enhanced images in acute and chronic phases of ON (P = .0001, P < .0001, and P = .0022, respectively), apparent diffusion coefficient values of the optic nerves in acute ON, chronic ON, and control groups also differed significantly from each other.

Conclusion

In conclusion, DWI can add valuable information in assessment of damage to nerve and neuronal barriers and thus in predicting recovery in cases of ON.  相似文献   
66.
Obstructive sleep apnea is associated with increased cardiovascular morbidity and mortality. We investigated myocardial perfusion using real-time quantitative myocardial contrast echocardiography with concurrent assessment of macrovascular and microvascular endothelial dysfunction in normotensive subjects with moderate-to-severe obstructive sleep apnea, who were compared with hypertensive and healthy subjects, as well as the impact of continuous positive airway pressure treatment on obstructive sleep apnea subjects. We measured flow (hyperemia)-mediated dilation and response to glyceryl trinitrate of brachial artery (ultrasound), cutaneous perfusion responses to acetylcholine and sodium nitroprusside (laser Doppler), pulse wave velocity, and circulating endothelial and endothelial progenitor cells in a total of 108 subjects (n=36 each of matched obstructive sleep apnea, hypertension, and healthy cohorts). Subjects with obstructive sleep apnea and hypertension demonstrated abnormal myocardial perfusion (P<0.001 for both comparisons), attenuated brachial artery reactivity (P<0.001), and cutaneous perfusion responses (P<0.001) compared with healthy individuals. Both hypertensive and obstructive sleep apnea patients showed significant improvements in myocardial perfusion (P<0.01), brachial artery reactivity (P<0.001), and cutaneous perfusion responses (P<0.001) after 26 weeks of continuous positive airway pressure therapy. There were no significant differences in pulse wave velocity and endothelial cells across the 3 groups. Concomitant endothelial dysfunction and impaired myocardial perfusion are present in otherwise normal subjects with moderate-to-severe obstructive sleep apnea, and effective continuous positive airway pressure treatment reverses many of these macrovascular/microvascular abnormalities.  相似文献   
67.
Cemented total hip arthroplasty has been being practiced successfully all over the world for the last 5 decades. Osteoarthritis is the most common indication of total hip arthroplasty. This study was done to observe the outcome of primary total hip arthroplasty by cemented prosthesis in secondary osteoarthritis of the hip joint. This prospective study was conducted at the department of Orthopaedics, Bangabandhu Sheikh Mujib Medical University and some private hospitals in Dhaka, Bangladesh from May 2008 to December 2009. Total 21 patients were evaluated. Among them 38.1% had rheumatoid arthritis, 19.1% had ankylosing spondylitis and 42.8% had avascular necrosis. Average duration of postoperative hospital stay was 14.09 days. Regarding the functional outcome, 76.2% patients had excellent, 19.1% had good and 4.8% had fair outcome. So out of 21 cases, 95.2% had satisfactory and 4.8% had unsatisfactory outcome. Cemented total hip arthroplasty is an effective procedure for the management of secondary osteoarthritis of the hip joint.  相似文献   
68.
69.
The phytochemical investigation of the root bark of Cassia artemisioides (Gaudich. Ex. DC) Randell resulted in the isolation of one new anthraquinone 1,1′-dihydroxy-3,3′-dimethyl-8,8′-dimethoxy-6,6′-O-bianthraquinone (1) along with four known anthraquinones 1,6-dihydroxy-8-methoxy-3-methylanthraquinone (2), 1-hydroxy-8-methoxy-3-methylanthraquinone (3), 1,8-dihydroxy-6-methoxy-3-methylanthraquinone (4), and 1,6,8-trihydroxy-3-methylanthraquinone (5). The structures of the compounds were elucidated using spectroscopic techniques including 1D and 2D NMR. The compounds were evaluated for antioxidant activity. 1,6,8-Trihydroxy-3-methyl anthraquinone (5) showed good activity among the tested compounds.  相似文献   
70.

Purpose:

To create a reliable rat model with small renal cortical scars and evaluate the accuracy and sensitivity of dynamic contrast‐enhanced MRI in detecting the kinds of lesions that are associated with reflux nephropathy.

Materials and Methods:

In 16 rats, three unilateral renal cortical lesions were created using either electrocautery or pure alcohol with the contralateral kidney serving as control. MRI on a 1.5 Tesla GE Signa was performed 10–14 days after surgery. After bolus injection of 0.2 mM/Kg Gd‐DTPA, sequential MRI acquisitions were performed using a 4‐inch quadrature birdcage coil. Renal and scar volumes and pathology were compared after scanning and killing.

Results:

Of the 48 points of injury, 40 (83%) in the 16 rats were detected grossly. Under microscopy, 36 injuries (75%) were detected on mid‐kidney cross‐sections. The average lesion was 4.2 mm3 corresponding to 0.5% of the kidney volume. Using pathological findings as the gold standard, the sensitivity and specificity of scar detection using MRI was 69% and 93%, respectively.

Conclusion:

A rat model was created to demonstrate the sensitivity of dynamic contrast‐enhanced MRI for detecting renal scars. Alcohol and electrocautery created reliable renal scars that were confirmed pathologically. MRI detected these lesions that averaged 4.2 mm3 (0.5% total renal volume) with sensitivity and specificity of 69% and 93%, respectively. J. Magn. Reson. Imaging 2010;31:1132–1136. © 2010 Wiley‐Liss, Inc.  相似文献   
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