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1.
Cholesterol distribution in tumoral tissues and lipid composition in the plasma compartment were determined in patients affected by different histologic types of lung cancer. The results showed that tumoral lung tissues contained 2-fold more total cholesterol and 3.5-fold more esterified cholesterol than normal lung tissues. In the patients the alterations in intracellular cholesterol were also associated with peculiar changes in cholesterol distribution in the plasma compartment. Serum high-density lipoprotein (HDL) cholesterol levels were markedly lower in than in controls. No significant changes in other lipid parameters were observed in these patients. We suggest that the reduced levels of serum HDL cholesterol observed in patients with lung tumors may be a consequence of the disease, probably mediated by the greater utilization of cholesterol for new membrane biogenesis and by the accumulation of esterified cholesterol in tumoral tissues.  相似文献   
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Mitochondrial impairment has been implicated in the pathogenesis of the amyotrophic lateral sclerosis (ALS). Furthermore, mitochondrial-specific polymorphisms were previously related to other neurodegenerative diseases, such as Parkinson, Friedreich and Alzheimer disease. To investigate if specific genetic polymorphisms within the mitochondrial genome (mtDNA) could act as susceptibility factors and contribute to the clinical expression of sporadic ALS (sALS), we have genotyped predefined European mtDNA haplogroups in 222 Italian patients with sALS and 151 matched controls. Individuals classified as haplogroup I demonstrated a significant decrease in risk of ALS versus individuals carrying the most common haplogroup, H (odds ratio 0.08, 95% confidence interval 0.04-0.4, p < 0.01). Further stratification of the dataset by sex, age and site of onset of disease and survival failed to reach significance for association. Our study provides evidence of the contribution of mitochondrial variation to the risk of ALS development in Caucasians. Further it may help elucidate the mechanism of the mitochondrial dysfunction detectable in ALS, and may be of relevance in development of strategies for the treatment of this disease.  相似文献   
3.
Sexual dimorphism exists in the response of rats to lead nitrate, liver hyperplasia occuring earlier and being more pronounced in males. Excess dietary choline in females shifted the growth pattern towards that of males. To determine whether phosphatidylcholine-induced growth modulations could be related to a derangement of cholesterol metabolism, liver accumulation of cholesterol esters and plasma lipoprotein patterns were investigated. In males, lead-induced liver hyperplasia was associated with increased total cholesterol hepatic content, accumulated cholesterol esters and reduced concentration of plasma High Density Lipoprotein (HDL) cholesterol. Females were less responsive to the liver mitogenic signal of lead nitrate; there was no elevation of cholesterol content nor any marked accumulation of cholesterol esters. This is consistent with the lack of change in the plasma levels of HDL cholesterol. Continuous choline feeding displaced the liver cholesterol ester pattern and plasma HDL cholesterol levels in females, and in parallel that of DNA synthesis, towards those of males. Choline was not observed to have any effect in males. These results suggest that the derangement of phosphatidylcholine metabolism induces growth-related changes in cholesterol turnover; they are consistent with the proposal that the intracellular content of cholesterol esters may have a role in regulating liver growth rates.  相似文献   
4.
We report the first surgical series of patients developing pleural empyema after severe bilateral interstitial lung disease in confirmed severe acute respiratory syndrome coronavirus 2 infection. The empyema results in a complex medical challenge that requires combination of medical therapies, mechanical ventilation and surgery. The chest drainage approach was not successful to relieve the symptomatology and to drain the excess fluid. After multidisciplinary discussion, a surgical approach was recommended. Even though decortication and pleurectomy are high-risk procedures, they must be considered as an option for pleural effusion in Coronavirus disease-positive patients. This is a life-treating condition, which can worsen the coronavirus disease manifestation and should be treated immediately to improve patient’s status and chance of recovery.  相似文献   
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Previous studies have shown that affective symptoms are part of the clinical picture in amyotrophic lateral sclerosis (ALS), the most common motor neuron disorder in elderly people. Diffuse neurodegeneration of limbic regions (e.g., prefrontal cortex [PFC], amygdala) was demonstrated in ALS post-mortem, although the mechanisms of emotional dysregulation in ALS in vivo remain unclear. Using functional imaging, we assessed the brain responses to emotional faces in 11 cognitively unimpaired ALS patients and 12 healthy controls (HCs). We tested whether regional activities and connectivity patterns in the limbic system differed between ALS patients and HCs and whether the variability in clinical measures modulated the neuroimaging data. Relative to HCs, ALS patients displayed greater activation in a series of PFC areas and altered left amygdala–PFC connectivity. Anxiety modulated the right amygdala–PFC connectivity in HCs but not in ALS patients. Reduced right premotor cortex activity and altered left amygdala–supplementary motor area connectivity were associated with longer disease duration and greater disease severity, respectively. Our findings demonstrate dysfunctions of the limbic system in ALS patients at early stages of the disease, and extend our knowledge about the interplay between emotional brain areas and the regions traditionally implicated in motor control.  相似文献   
7.
BACKGROUND: During neoplastic progression, alterations in transforming growth factor beta1 (TGF-beta1) dependent control of cell growth may be an important mechanism of selective proliferation of transformed cellular clones. Defective regulation of TGF-beta1 receptors has been reported to occur in a number of human malignant tumours while little is known of the actual levels of this growth inhibitory cytokine in cancer. On the basis of the demonstrated ability of major lipid peroxidation products such as 4-hydroxynonenal to modulate TGF-beta1 expression and synthesis, we speculated that decreased lipid oxidation, as frequently observed in neoplastic tissues, would contribute to the selective promotion of tumour growth through decreased expression of the cytokine within the tumour mass. AIMS: To seek a possible association between steady state levels of major aldehydic end products of lipid peroxidation and TGF-beta1 content in human colon cancer at different stages of growth. PATIENTS AND METHODS: Tissue biopsies from 15 adult patients with colon adenocarcinoma of different TNM and G stagings were compared with regard to lipid peroxidation aldehydes and net TGF-beta1 levels. For a more comprehensive analysis, cytokine type I and II receptors were measured in tumour biopsies. In one set of experiments, to support the conclusions, the apoptotic effect of TGF-beta1 was evaluated in a human colon cancer cell line, CaCo-2, retaining receptor changes consistent with those observed in cancer patients. RESULTS: With the exception of two extremely advanced cases (T4/G3) in which tissue levels of lipid peroxidation were within the normal range, 4-hydroxynonenal was significantly decreased in all other cancer specimens. Consistent with lipid peroxidation levels, TGF-beta1 protein was markedly decreased or even negligible compared with the corresponding normal tissue surrounding the tumour in all tested biopsies except for the two T4/G3 colon cancers in which cytokine content was again within the normal range. As regards TGF-beta1 receptors, both in tumour sections and CaCo-2 cells, downregulation was greater for TGF-beta1 receptor I than for receptor II. Of note, in CaCo-2 cells, incubation with appropriate doses of TGF-beta1 led to marked nuclear fragmentation and apoptosis. CONCLUSIONS: Evasion of human colon cancer cells from TGF-beta1 mediated growth inhibition appears to be due not only to downregulation of TGF-beta1 receptors, which is inconsistent and unrelated to cancer development, but also to the constant low concentration of this cytokine in the tumour mass. The associated levels of lipid peroxidation aldehydes, much lower than in control tissue, probably represent a lower stimulus for TGF-beta1 production in the neoplastic area and thus a favourable condition for neoplastic progression.  相似文献   
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We report a rare case of renal carcinoma metastasis involving a lumbar nerve root. Metastases to nerve roots are rare occurrences, and to our knowledge, only six cases have been reported so far in the literature. The patient in this report presented with weakness in the right lower limb and intractable pain irradiating along the L5 dermatome. MRI findings revealed a right-sided L5 nerve root mass, suggestive of a schwannoma, involving the spinal ganglion and its extraforaminal region. Complete macroscopic resection of this mass was performed, and histopathologic analysis confirmed the lesion to be a metastasis of a renal clear cell carcinoma. Local radiotherapy was given and tyrosine kinase inhibitors administered. At 5 months, the patient was pain-free and his right limb weakness had completely resolved. A tumoral recurrence could be observed on the control MRI 5 months after surgery. This report presents the first case of a patient with a renal clear cell carcinoma metastasis to a L5 nerve root, as well as a brief review of previous cases of metastases to peripheral nerve roots.  相似文献   
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