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101.
One of the fundamental principles underlying tissue engineering approaches is that newly formed tissue must maintain sufficient vascularization to support its growth. Efforts to induce vascular growth into tissue-engineered scaffolds have recently been dedicated to developing novel strategies to deliver specific biological factors that direct the recruitment of endothelial cell (EC) progenitors and their differentiation. The challenge, however, lies in orchestration of the cells, appropriate biological factors, and optimal factor doses. This study reports an approach as a step forward to resolving this dilemma by combining an ex vivo gene transfer strategy and EC transplantation. The utility of this approach was evaluated by using 3D poly(lactide-co-glycolide) (PLAGA) sintered microsphere scaffolds for bone tissue engineering applications. Our goal was achieved by isolation and transfection of adipose-derived stromal cells (ADSCs) with adenovirus encoding the cDNA of VEGF. We demonstrated that the combination of VEGF releasing ADSCs and ECs results in marked vascular growth within PLAGA scaffolds. We thereby delineate the potential of ADSCs to promote vascular growth into biomaterials.  相似文献   
102.

Aims

This study was done to assess the risk factors associated with diabetic foot ulcer-free survival in patients with diabetes.

Materials and Methods

Based on a prospective cohort study, ADFC (Ahvaz Diabetic Foot Cohort) study, carried out in a university hospital, all of the patients with diabetes were followed up for new diabetic foot ulcer (DFU). The time of ulcer development was final outcome during two years in the present study. To analyze the data, the variables were first evaluated by univariate analysis. Subsequently variables with P value <0.2 were tested in multivariate analysis, using backward elimination multiple Cox regression.

Results

From among 605 eligible patients of ADFC study, 566 patients without foot ulcer were included for a 2- years follow-up. Thirty subjects (5.3%) developed DFU during the study course none of whom underwent amputation. The DFU-free survival rate was 0.945 over two years of follow-up. In final multivariate Cox regression analysis, the variables which remained in the model and had a statistically significant relationship with time to develop foot ulcer were: dyslipidemia, history of DFU or amputation, nephropathy callus formation in the feet and diabetes duration. Foot deformity and patients' training about self-care of their feet were statistically borderline significant.

Conclusions

The DFU-free survival rate was 0.945 over two years of follow-up. In this study, independent risk factors associated with ulcer-free survival in diabetic foot patients were dyslipidemia, prior history of DFU or amputation, diabetic nephropathy, callus formation in the feet and diabetes duration.  相似文献   
103.
Purpose.?To alert health professionals on presence and extent of phantom pain and sensation following bilateral upper limb amputation.

Methods.?Of a total of 140 war-related bilateral upper limb amputees in Iran, 103 subjects were thoroughly examined in this cross-sectional study by a physical medicine specialist. The patients were questioned for the presence of phantom pain and sensations, and frequency and intensity of the feeling were recorded.

Results.?At 17.1 ± 6.1 years after injury, 82.0% of the 103 amputees suffered from phantom sensation, including varying degrees of phantom limb pain in 53.9% of stumps. Phantom phenomena had a higher frequency in the right extremities, but this was not statistically significant (p > 0.01). Of those amputees who had phantom pain or sensation, 51.2% reported that they ‘always’ had phantom limb sensation; and approximately one-fourth of the subjects (24.6%) ‘always’ had phantom pain. Among the stumps who reported phantom pain (N = 112), the pain was excruciating (38.5%), distressing (34.9%) or discomforting (25.6%). A significant statistical relation between phantom limb sensation and level of amputation was observed (p < 0.01).

Conclusion.?At this time there is no healing for phantom pain; medical and surgical modalities only bring temporary relief, and less than 1% of the respondents achieve permanent relief through different treatment methods.  相似文献   
104.
Abstract: The effect of morphine on the α-methyl-p-tyrosine (αMT)-induced depletion of dopamine (DA) and noradrenaline (NA) was studied in various brain areas of male NMRI mice, whose locomotor activity is clearly stimulated by morphine. Morphine (10 mg/kg) accelerated the αMT-induced DA depletion in the striatum and in the area “rest of forebrain + midbrain”, which contains the limbic dopaminergic neurons, but did not clearly alter it in the hypothalamus. The effects were blocked by naloxone. The enhancement of the striatal DA depletion was attenuated when morphine was given after αMT or when morphine dose was increased to 30 mg/kg. The smallest dose of morphine to enhance the αMT-induced NA depletion in the forebrain + midbrain area was 3 mg/kg, and in the hypothalamus and the lower brain stem 10 mg/kg. The enhancement of the NA depletion was dose-dependent, occurred whether morphine was given before or after αMT, and was blocked by naloxone. Our findings suggest that morphine alters the αMT-induced depletion of cerebral DA in mice similarly to what has been reported to occur in rats. In contrast its effects on cerebral NA depletion in mice are clearly different from its effects in rats. The substantial activation of cerebral noradrenergic systems, especially of those in the forebrain + midbrain area, in mice could underly the fact that morphine's predominant behavioural effect in mice is stimulation of motor activity.  相似文献   
105.
Contiguous spread along perineural and endoneural spaces, that is, perineural tumor extension, in cutaneous squamous cell carcinoma is fairly common. Infrequently, these tumors spread and involve intracranial structures. One consequence of th1s complication is meningeal carcinomatosis which is underrecognized. Herein described is a patient with recurrent cutaneous squamous cell carcinoma with perineural invasion along the maxillary nerve that was subsequently shown by magnetic resonance imaging to the trigeminal root The patient Initially presented with a cavernous sinus syndrome but despite aggressive treatment, extensive meningeal carcinomatosis and cauda equina dysfunction developed. Awareness of perineural invasion and proper evaluation are crucial. Penneural spread intracranially worsens the prognosis and limits treatment options to palliation.  相似文献   
106.
A man developed spontaneous spinal epidural hematoma secondary to ruptured hemangioma with a clinical picture resembling acute partial Brown-Sequard syndrome. Diagnosis by magnetic resonance imaging (MRI) allowed prompt surgical decompression and complete reversal of the neurological deficits. The diagnosis, etiology, and MRI findings of spinal epidural hematomas are discussed.  相似文献   
107.
108.
Gazi E  Baker M  Dwyer J  Lockyer NP  Gardner P  Shanks JH  Reeve RS  Hart CA  Clarke NW  Brown MD 《European urology》2006,50(4):750-60; discussion 760-1
OBJECTIVES: We introduce biochemistry as a second dimension to Gleason grading, using Fourier transform infrared (FTIR) microspectroscopy. For the first time, we correlate FTIR spectra derived from prostate cancer (pCA) tissue with Gleason score and the clinical stage of the tumour at time of biopsy. METHODS: Serial sections from paraffin-embedded pCA tissue were collected. One was stained with hematoxylin and eosin and Gleason scored; FTIR spectra were collected from malignant locations using a second unstained section. FTIR spectra, representing different Gleason grades, were used to construct a diagnostic classifier for pCA using linear discriminant analysis (LDA). This model was blind tested using 383 IR spectra from 36 biopsies. RESULTS: Using a three-band Gleason criteria, we obtained sensitivity of > or =70% for the FTIR-LDA model to predict Gleason <7,=7, and >7, with specificities of > or =81%. Using a threshold of Gleason/FTIR-LDA score of > or =8, we obtained a sensitivity and specificity of 71% and 67%, respectively, for the correlation with metastatic tumours using the FTIR-LDA system and 85% and 63%, respectively, for the correlation of metastatic tumours using the Gleason system. CONCLUSIONS: There is a correlation between tissue architecture using Gleason score with tissue biochemistry using FTIR-LDA. Both systems are similar in their performance in predicting metastatic behaviour in tumours from individual patients.  相似文献   
109.
Hypertension is a prevalent chronic illness that is implicated in many cardiovascular diseases. Practice nurses and the district nursing team have a major role to play in its management. In this article, current British Hypertension Society guidelines are presented and discussed with regards to their evidence base. Implications for nursing practice are highlighted.  相似文献   
110.
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