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1.
Current bladder cancer tests: unnecessary or beneficial?   总被引:4,自引:0,他引:4  
Bladder cancer is currently diagnosed using cystoscopy and cytology in patients with suspicious signs and symptoms. These same tests are used to monitor patients with a history of bladder cancer for recurrence. The recurrence rate for bladder cancer is high, thus necessitating long-term follow-up. Urine cytology requires an experienced cytopathologist and is costly. It has high specificity, but low sensitivity for low-grade bladder tumors. Recently many non-invasive bladder cancer tests, utilizing markers found in the urine, have been developed. The FDA has approved several of these for the use is bladder cancer diagnosis, and many others are undergoing development and investigation. An ideal bladder cancer test would be non-invasive, highly sensitive and specific, inexpensive, easy to perform, and yield highly reproducible results. Many of the tests reviewed meet some, but not all, of these criteria.  相似文献   
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PURPOSE: Poor efficacy of conventional chemotherapeutic drugs against metastatic hormone-refractory prostate cancer (CaP) drives patients to try "alternative medicine". The antitumor activity of one such agent, "BIRM" (biological immune response modulator; "Simple Ecuadorian Oral Solution: an extract of an Amazonian plant"), was characterized in vitro and in vivo using established CaP cell lines and a tumor model. METHODS: The cytotoxicity of BIRM in four human and one rat CaP cell line was evaluated using cell proliferation-inhibition and clonogenic survival assays. BIRM-induced apoptosis, alterations in cell cycle phase progression and inhibition of the extracellular matrix-degrading enzyme hyaluronidase were also investigated in these cells. The in vivo efficacy of BIRM was evaluated in rats with subcutaneous tumor implants of Dunning EGFP-MAT LyLu cells. The active species in BIRM were characterized by gel filtration chromatography. RESULTS: BIRM inhibited cell proliferation and clonogenic growth of the CaP cells (IC(50) about 8.0 microl/ml). It increased cell accumulation in the G(0)/G(1) phase by 33.8% and decreased the proportion of cells in S phase by 54.6%. Apoptotic cell death in BIRM-treated cells was associated with activation of cell death-associated caspases. BIRM inhibited the activity of hyaluronidase, a hyaluronic acid-degrading enzyme, at 1 microl/ml. Treatment of MAT LyLu tumor-bearing rats with BIRM by oral gavage resulted in a significant decrease in tumor incidence (50%), tumor growth rate (18.6+/-1.3 days for 1 cc tumor growth in control rats and 25.7+/-2.6 days in BIRM-treated rats), and only one out of six BIRM-treated rats versus four out of six in the control group developed lung metastasis. Three active ingredients in BIRM with a relative molecular mass (Mr) of >or=3500 were identified by ultracentrifugation and gel filtration chromatography and were found to be resistant to proteinase and heat (100 degrees C). CONCLUSION: The plant extract BIRM contains antitumor compounds of Mr >or=3500 with potent antiproliferative activity in vitro and in vivo against prostate cancer cells.  相似文献   
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Rahman M  Deleyrolle L  Vedam-Mai V  Azari H  Abd-El-Barr M  Reynolds BA 《Neurosurgery》2011,68(2):531-45; discussion 545
Based on the clonal evolution model and the assumption that the vast majority of tumor cells are able to propagate and drive tumor growth, the goal of cancer treatment has traditionally been to kill all cancerous cells. This theory has been challenged recently by the cancer stem cell (CSC) hypothesis, that a rare population of tumor cells, with stem cell characteristics, is responsible for tumor growth, resistance, and recurrence. Evidence for putative CSCs has been described in blood, breast, lung, prostate, colon, liver, pancreas, and brain. This new hypothesis would propose that indiscriminate killing of cancer cells would not be as effective as selective targeting of the cells that are driving long-term growth (ie, the CSCs) and that treatment failure is often the result of CSCs escaping traditional therapies.The CSC hypothesis has gained a great deal of attention because of the identification of a new target that may be responsible for poor outcomes of many aggressive cancers, including malignant glioma. As attractive as this hypothesis sounds, especially when applied to tumors that respond poorly to current treatments, we will argue in this article that the proposal of a stemlike cell that initiates and drives solid tissue cancer growth and is responsible for therapeutic failure is far from proven. We will present the point of view that for most advanced solid tissue cancers such as glioblastoma multiforme, targeting a putative rare CSC population will have little effect on patient outcomes. This review will cover problems with the CSC hypothesis, including applicability of the hierarchical model, inconsistencies with xenotransplantation data, and nonspecificity of CSC markers.  相似文献   
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6-Aminocoumarins on refluxing with ethyl acetoacetate in 1,2-dichloroethane gave two products: 3'-(2-oxo-2H-benzopyran-6-yl-amino)-but-2'-enoic acid ethyl ester 2a-c and N-(-2-oxo-2H-benzopyran-6-yl)-3'-oxo-butyramide 3a-c. Compounds 2a-c on treatment with 1,4-benzoquinone in N2-atmosphere yielded 1'-( 2-oxo-2H-benzopyran-6-yl)-5'-hydroxy-2'-methyl-3'-carbethoxyindoles 4a-c, which on further treatment with hydrazine hydrate gave 1'-(2-oxo-2H-benzopyran-6-yl)-5'-hydroxy-2'-methylindole-3'-acid hydrazides 5a-c. These acid hydrazides were treated with benzaldehyde to give 1'-(2-oxo-2H-benzopyran-6-yl)-5'-hydroxy-2'-methylindole-3'-benzylidene hydrazides 6a-c, which on further treatment with mercaptoacetic acid in 1,4-dioxane yielded 1'-(2-oxo-2H-benzopyran-6-yl)-5'-hydroxy-2'-methylindole-3'-amido-2"-phenylthiazolidene-4"-ones 7a-c. The structures of the compounds have been established on the basis of spectral and analytical data. All compounds have been screened for their antimicrobial activity and have been found to exhibit significant antibacterial and antifungal activities.  相似文献   
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6-Aminocoumarin on treatment with oxalyl chloride gives coumarinyl-6-isocynate (1a-c) which on treatment with glycine gives 1H-3-[2'-oxo-2'H-benzopyran-6'-yl]-5-imidazolidine-2, 4-dione (2a-c). (2a-c) when refluxed with o-chlorobenzaldehyde, m-hydroxybenzaldehyde, 3,4-dimethoxybenzaldehyde and 3-nitrobenzaldehyde separately gives 1H-5-(2"-chlorobenzylidene)-3-(2'-oxo-2'H-benzopyran-6'-yl) imidazolidine-2,4-dione (3a-c), 1H-5-(3"-hydroxybenzylidene)-3-(2'-oxo-2'H-benzopyran-6'-yl) imidazolidine-2,4-dione (4a-c), 1H-5-(3",4"-dimethoxybenzylidene)-3-(2'-oxo-2'H-benzopyran-6'-yl) imidazolidine-2,4-dione (5a-c) and 1H-5-(3"-nitrobenzylidene)-3-(2'-oxo-2'H-benzopyran-6'-yl) imidazolidine-2,4-dione (6a-c), respectively. 3-(2"-Chlorophenyl)-3a,4-dihydro-6-(2'-oxo-2'H-benzopyran-6'-yl) imidazo[4,5-c]isoxazol-5-one 7a-c is obtained from (3a-c) and hydroxylamine hydrochloride while 2,3a,4-trihydro-3-(3"-hydroxyphenyl)-6-(2'-oxo-2'H-benzopyran-6'-yl) imidazo[4,5-c]pyrazol-5-one (8a-c) obtained by reaction of (4a-c) with hydrazine hydrate. Compound (5a-c) on treatment with urea gives 5,7-dihydro-2-hydroxy-6-(3",4"-dimethoxyphenyl)-9-(2'-oxo-2'H-benzopyran-6'-yl) purin-8-one (9a-c) and compound (6a-c) on treatment with thiourea gives 5,7-dihydro-2-mercapto-6-(3"-nitrophenyl)-9-(2'-oxo-2'H-benzopyran-6'-yl)purin-8-one (10a-c). The structures of the compounds have been established on the basis of spectral analytical data. All the compounds have been screened for their antimicrobial activities against three bacterial strains S. aureus, S. typhi and E. coli. Compounds 2b, 3b, 4b, 5b, 6b, 7b, 8b, 9b and 10b with the presence of methyl groups at C7' and C8' of coumarin moiety were found to be more active than others.  相似文献   
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Originally termed as the “spreading factor”, hyaluronidases (HAases) are present in a variety of toxins and venoms. For example, HAase is the virulent factor of β-hemolytic Streptococci and it is also present in the venoms of snake, bee, wasp, scorpion, etc, where it aids in the spread of these venoms in the body. In mammals, testicular HAase present in the sperm acrosome is necessary for the fertilization of the ovum. Despite a lot of work on bacterial, invertebrate and testicular HAases, a connection between HAase and cancer was unequivocally established just over a decade ago and the functional significance of HAases in cancer was demonstrated just about a year ago. In this part of the review, we will focus on the recent advances in our understanding of the role of HAases in cancer.  相似文献   
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Bladder cancer is a common malignancy in the USA. Currently, the detection of initial tumors and recurrent disease is based on evaluation of voided urinary specimens, often followed by cystoscopy. With the high rate of recurrence, cystoscopies are regularly repeated with the aim of halting progression of the disease. For patients, this process is fraught with anxiety, pain and high cost. As a result, intense work is being done in the field of bladder tumor markers with the goal of identifying bladder cancer earlier, both in the initial diagnosis and in recurrences of known tumor. The possibility of identifying a marker that could noninvasively differentiate benign and malignant causes of hematuria, and identify recurrences prior to their pathologic progression is the objective of this area of research. Currently, a large number of tumor markers exist, each scrutinized in both the laboratory and in clinical trials. Here we present many of the most widely used and tested markers. Background details are provided as to the mechanism of detection of malignant cells, the results of recent trials and future directions of study. Some novel modalities for tumor detection are also presented. The next few years will no doubt bring newer markers and lead to the elimination of others. Studies continue to refine the role of these markers in clinical practice, but their ultimate efficacy will need to be borne out in large-scale clinical trials in a multitude of settings.  相似文献   
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