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1.
The direct causal relationship between dermatomyositis-polymyositis (PM) and malignancy remains controversial. We describe herein the case of a patient who underwent surgical treatment for colon cancer, which had preceded the onset of PM with tumor relapse. The PM markedly improved following the initiation of steroid therapy, and has remained under control, probably as a result of chemotherapy. The current concepts of variable clinical courses and the possible mechanism for the association of PM with malignancy are discussed following this case report.  相似文献   
2.
The structure-acute toxicity relationship of aromatic hydrocarbons was examined in mice. In all test compounds, the acute toxicity was determined under 2 conditions: control LD50 (LD50-cont) and carbon tetrachloride (CCl4)-pretreated LD50 (LD50-CCl4). The CCl4-pretreatment was done in order to evaluate the toxic potency of compound itself without the influence of metabolism. Both log (1/LD50-cont) and log (1/LD50-CCl4) were functions of the log P, n-octanol/water partition coefficient, i.e., log (1/LD50-cont) = 0.080 log P − 1.532 and log (1/LD50-CCl4) = −0.040(log P)2 + 0.157 log P − 1.373. Both equations were statistically significant (P < 0.01). The ratio of LD50-cont/LD50-CCl4 indicated that metabolic activation is more evident in hydrophobic compounds than in hydrophilic compounds. The results suggest that hydrophobicity of the aromatic hydrocarbons plays an important role in determining their acute toxicity.  相似文献   
3.
Primary extranodal malignant lymphoma frequently occurs in the gastrointestinal tract; however, it is rarely encountered in the rectum. We report herein the case of an 85-year-old man who underwent abdominoperineal resection for primary malignant lymphoma of the rectum, and 1 year later, developed hematemesis caused by gastric metastasis. To our knowledge this is the first case report of such distant metastasis developing from malignant lymphoma of the rectum.  相似文献   
4.
We have investigated the effect of the immunomodulator ubenimex (hereafter referred to as bestatin) on the enzymatic degradation of the extracellular matrix by human renal cell carcinoma SN12M cells during the invasive process. The invasion of SN12M cells into reconstituted basement membrane (Matrigel) was inhibited by the presence of bestatin in a concentration-dependent manner. However, bestatin did not have any effect on tumor cell adhesion and migration to the extracellular matrices which may be involved in tumor cell invasion. Bestatin inhibited the degradation of type IV collagen by tumor cells, but not by tumor-conditioned medium (TCM), in a concentration-dependent manner. We also found that bestatin inhibited hydrolysing activities towards substrates of aminopeptidases in SN12M cells. Since bestatin was found to inhibit aminopeptidase activity, the inhibition of tumor invasion by bestatin is likely to be associated with its action as an enzyme inhibitor. Bestatin only slightly inhibited tumor cell plasmin activity, which can lead to the conversion of the latent collagenase to the active form, but this slight effect was not significant. The zymography of TCM from SN12M cells showed that the treatment of tumor cells with bestatin resulted in the disappearance of the 68 kDa type IV collagenase-enzyme level (active form) and slight reduction of the 72 kDa type IV collagenase-enzyme level (latent form). These results indicated that bestatin may inhibit tumor cell invasion through a mechanism involving its inhibitory action on aminopeptidases in tumor cells, suggesting that the aminopeptidase may partly be associated with the conversion of a latent form of type IV procollagenase to an active form or the secretion of the collagenases from tumor cells.  相似文献   
5.
Abstract A 13-year-old girl with a history of Kawasaki disease underwent coronary artery bypass grafting because of angina pectoris due to a giant coronary artery aneurysm on the left main trunk artery. Nine years after the operation, the patient had an uneventful pregnancy followed by a normal vaginal delivery. This is the first case of a successful pregnancy after coronary artery bypass grafting for Kawasaki coronary artery disease.  相似文献   
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7.
Background: Patients with advanced hepatocellular carcinoma (HCC) need an effective treatment modality because of the poor prognosis of the disease. From an in vitro study, beta-interferon (IFN-beta) has been reported to enhance the antiproliferative effects of doxorubicin on HCC cell lines. In the present study, we investigated the therapeutic effects of combined IFN-beta and doxorubicin intra-arterial injection therapy on patients with advanced HCC. Methods: IFN-beta (3 MIU) and doxorubicin (10 mg/bodyweight) were given by one-shot intra-arterial injection through an arterial port to patients with advanced HCC. One treatment course consisted of three intra-arterial injections per week for 4 weeks. Three courses were conducted and evaluation was done monthly. Results: Eleven patients with advanced HCC were treated with combined IFN-beta and doxorubicin. One patient enteredcomplete remission (CR), seven patients were evaluated as having stable disease (SD) and three as having progressive disease (PD). The mean overall survival was 10 months. The mean survival for CR and SD patients was 15 months, and that for PD patients was 6 months (P = 0.0464, log-rank test). Decrease of serum total bilirubin was observed for all patients. Conclusion: Combined IFN-beta and doxorubicin intra-arterial therapy offers an effective chemotherapy option for patients with advanced HCC by improving liver function and having tolerable side-effects.  相似文献   
8.
BACKGROUND/AIMS: Human hepatoma-derived growth factor, purified from the conditioned medium of hepatoma-derived cell line, HuH-7, stimulates the growth of Swiss 3T3 fibroblasts and HuH-7 cells. To evaluate the role of hepatoma-derived growth factor on the growth of hepatoma cells, we investigated the effects of recombinant hepatoma-derived growth factor protein and hepatoma-derived growth factor antisense oligonucleotides on the proliferation of several hepatoma cell lines. METHODOLOGY: We examined the effects of hepatoma-derived growth factor antisense oligonucleotides on the growth of hepatoma cells by cell growth assay. RESULTS: Hepatoma-derived growth factor stimulated the proliferation of some hepatoma cells (HuH-7, HLF, HepG2, AH66tc cells) about 15-70% over than the control. Hepatoma-derived growth factor antisense oligonucleotides, phosphorothioate-linked or encapsulated in liposome, can inhibit the growth of hepatoma cells. The ID50 of hepatoma-derived growth factor antisense phosphorothioate oligonucleotides for HuH-7 cells, in which hepatoma-derived growth factor expression was abundant, was 3 microM by the assay of cell proliferation and [3H]-thymidine incorporation. Their ID50 for AH66tc cells, on which the effects of exogenous hepatoma-derived growth factor were weak, was higher than 10 microM. To omit the toxic effects due to phosphorothioate modification of oligonucleotides and keep the cellular uptake more without their destruction in the culture medium, we used oligonucleotides encapsulated in cationic liposome. Hepatoma-derived growth factor antisense oligonucleotides encapsulated in liposome suppressed the growth of hepatoma cells effectively (ID50:2.0 microM). CONCLUSIONS: These findings suggest that hepatoma-derived growth factor is one of important autocrine, and/or intracrine factors for hepatoma cells, and that hepatoma-derived growth factor anti-sense oligonucleotides may be useful for human hepatocellular carcinoma as an anti-cancer agent.  相似文献   
9.
The term ‘emphysema’ is generally used in a morphological sense, and therefore imaging modalities have an important role in diagnosing this disease. In particular, high resolution computed tomography (HRCT) is a reliable tool for demonstrating the pathology of emphysema, even in subtle changes within secondary pulmonary lobules. Generally, pulmonary emphysema is classified into three types related to the lobular anatomy: centrilobular emphysema, panlobular emphysema, and paraseptal emphysema. In this pictorial review, we discuss the radiological – pathological correlation in each type of pulmonary emphysema. HRCT of early centrilobular emphysema shows an evenly distributed centrilobular tiny areas of low attenuation with ill-defined borders. With enlargement of the dilated airspace, the surrounding lung parenchyma is compressed, which enables observation of a clear border between the emphysematous area and the normal lung. Because the disease progresses from the centrilobular portion, normal lung parenchyma in the perilobular portion tends to be preserved, even in a case of far-advanced pulmonary emphysema. In panlobular emphysema, HRCT shows either panlobular low attenuation or ill-defined diffuse low attenuation of the lung. Paraseptal emphysema is characterized by subpleural well-defined cystic spaces. Recent topics related to imaging of pulmonary emphysema will also be discussed, including morphometry of the airway in cases of chronic obstructive pulmonary disease, combined pulmonary fibrosis and pulmonary emphysema, and bronchogenic carcinoma associated with bullous lung disease.  相似文献   
10.
BackgroundThe utilities of magnetic cervical motor root stimulation are well known for lesions in the lower part of the brachial plexus, but not for lesions in the other parts.ObjectiveThe aim of paper is to show the utilities of magnetic cervical motor root stimulation for lesions in the upper part of the brachial plexus.MethodsWe analyzed the brachial plexus using both electrical stimulation at Erb's point and magnetic cervical motor root stimulation in a patient with brachial plexopathy caused by tumor invasion.ResultsOn the fourth day after onset, magnetic cervical motor root stimulation revealed abnormal findings in the upper part of the brachial plexus. Two weeks after onset, needle electromyography supported the existence of the focal lesion.ConclusionMagnetic cervical motor root stimulation is useful in detecting abnormal findings in the upper part of the brachial plexus, even at the acute phase.  相似文献   
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