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91.
The colorectal cancer continues to be diagnosed in advanced stages in our country, mainly due to unapplying of a programmer of active diagnosis through screening on the population with risk for colorectal cancer, and inefficiency of primary care system. In the department of General Surgery CFR Craiova Hospital between 1991-2001 were operated a number of 231 patients with colon cancer and 104 patients with rectal cancer. The results, showing an increased number of recurrences in cases of resection performed for advanced loco-regional tumors of rectosigmoid, made us to reconsider the attitude of avoiding the abdominoperineal resection even when the distance between the inferior limits of the tumors and the anal edge exceeded the distance considered being standard for a low anastomosis performing. The follow-up of the patients with paraclinic technique that didn't prove efficient led in the most cases to a delaying in diagnosis of local recurrences until the moment of resectability was exceeded. The applying of efficient methods in early diagnosis of colorectal cancer and follow-up could provide in the future better results for anterior resections with low anastomosis.  相似文献   
92.
The aims of this paper are both to highlight some dilemmas concerning the diagnosis of primary epithelial ovarian carcinoma mainly in its early stages and to underline the capricious responses of this type of malignancy to an otherwise well coded modern management. This study is based on the analysis of the records of 78 patients with ovarian carcinoma admitted for diagnosis and surgical treatment to the Department of General Surgery of Craiova C.F.R. Clinic from 1993 through 2003. The results of this analysis are difficult to interpret due to loss to follow up (in terms of response rates) of some of our 78 operated on ovarian carcinoma patients who went on with their platinum-based chemotherapy (following surgical cytoreduction) under the supervision of different Oncology Departments nationwide. Nevertheless, it is worth mentioning that most of this study patients (71.9%) presented with advanced-stage (III and IV) ovarian carcinoma which sometimes seemed quite confusing by its clinical polymorphism but its prognosis was very much related to both the degree of surgical cytoreduction accomplished and tumor sensitivity to chemotherapy. Finally, although this study does not allow us to draw firm conclusions it is an attempt to share out our current perception on the primary epithelial ovarian cancer management.  相似文献   
93.
This laboratory has studied the enzymology involved in the biotransformation of inorganic arsenic to dimethylarsinous acid (DMA(III)) and in human studies established that monomethylarsonous acid (MMA(III)) and DMA(III) appear in urine of people chronically exposed to arsenic. It appears that only two proteins are required for inorganic arsenic biotransformation in the human, namely, monomethylarsonic acid (MMA(V)) reductase and arsenic methyltransferase. MMA(V) reductase and the unique glutathione transferase omega (hGST-O) are identical proteins. Arsenicals with a +3 oxidation state are more toxic than the +5 species. While methylation of arsenite, MMA(III), and DMA(III) produces less toxic +5 oxidation arsenic species containing an additional methyl group such as MMA(V), dimethylarsinic acid (DMA(V)), and TMAO, a new mechanism involving hydrogen peroxide for detoxifying arsenite, MMA(III), and DMA(III) is proposed based on in vitro experiments.  相似文献   
94.
Photodynamic therapy with protoporphyrin IX induced by delta-aminolevulinic acid (ALA) is mainly applied for the treatment of human superficial skin cancer. In this paper we present our study on photodynamic therapy (PDT) of the implanted Walker tumours using subcutaneous administration of ALA to improve the availability of ALA in the skin. We determined the accumulation and localization of protoporphyrin IX (PpIX) after subcutaneous administration of different concentrations of ALA in a physiological saline solutions, using fluorescence imaging technique. The results obtained indicate that PpIX accumulation depends on the concentration of ALA. The temporal behavior of PpIX fluorescence has shown a clear demarcation of tumoural zone depending on the post-administration time and the administrated concentration of the ALA solution. Further studies are needed to confirm these encouraging results and to define the PDT protocols using subcutaneous administration of ALA solution  相似文献   
95.
A 32-week, premature neonate with incessant supraventricular tachycardia and hemodynamic compromise who failed to respond to antenatal and postnatal antiarrhythmic therapy underwent successful radiofrequency catheter ablation (RCA) of a concealed left free-wall accessory pathway when the infant was 4-days-old and weighed only 1,840 grams. At follow-up performed 60 days after the procedure, the infant remained free of any drug, in sinus rhythm, and in normal hemodynamic condition.  相似文献   
96.
Causative agents of sexually transmitted diseases (STD) are different types of bacteria, viruses, fungi and protozoa. The last two decades of the twentieth century were marked with a sudden rise in the number of cases of STDs. Human immunodeficiency virus (HIV), which emerged in the 1980s, is the most prominent STD agent because of its fast spread and severity of the disease it causes, acquired immunodeficiency syndrome (AIDS). Beside HIV, human papillomaviruses (HPVs), herpes simplex viruses (HSVs) and Chlamydia trachomatis are nowadays among most health-threatening STD pathogens. In order to stop the spread of infection, apart from education about precautions, early detection of the disease is essential. Although most STD pathogens can be detected by classical methods of cultivation, biochemical and/or serologic methods, molecular diagnosis of infectious diseases has largely simplified and accelerated their detection. For instance, HPVs that cause benign and malignant tumors of genital skin and mucosa cannot be routinely detected on cell culture, whereas serologic analysis is not sensitive and informative enough. Moreover, cytologic (Pap smear) and histologic analyses can indicate changes associated with HPV infection, but neither of these methods can prove the presence of HPV. That is why the molecular methods are essential to demonstrate the presence of the infection and, even more important, to determine the type of the virus, which is associated either with low-grade or high-grade genital lesions. There are numerous methods based on hybridization with DNA or RNA probes, some of them are suitable for detecting wide range of types and screening of large collection of samples. However, the most sensitive and informative methods are based on polymerase chain reaction (PCR), and they have the advantage of being able to determine the type of the virus and distinguishing between multiple infections. Herein, we present when and why molecular analysis is useful and necessary for the detection of STD agents.  相似文献   
97.
Our study showed that the administration in pre-treatment of some polyamines (especially spermine and spermidine and almost null agmatine, putrescine and cadaverine) reduced the contractile effects of angiotensin II (Ang II) in isolated rat aorta. These effects might not be associated to the interference of clathrin coated vesicles (coated pits) formation or caveolae interaction (and thus to Ang II internalization through AT1 receptors). In contrast, these effects seem to be due to the interaction with voltage-gated membrane Ca2+ channels. Therefore, the alteration of transmembrane Ca2+ fluxes does not exclude the involvement of internalization process through coated pits or caveolae, since the endocytosis mediated by these phenomena essentially needs Ca2+. In addition, the inhibitory effects are dependent on the number of positive charges of the polyamine molecules.  相似文献   
98.
The authors are approaching the problem of hemolytic uremic syndrome, a common cause of acute renal failure in children. This review present an update about the pathophysiology of typical hemolytic uremic syndrome, useful for understanding the clinical picture and the base for some modern therapeutical models. Concerning the evolution, the authors underline the importance of identifying the risk factors for acute phase, the extrarenal manifestations being considered of vital risk. The atypical hemolytic uremic syndrome still has some uncertainties; the article try to make a synthesis of ethiopathogeneity, clinical manifestations, evolution and therapeutical modern approaches.  相似文献   
99.
Large interindividual variability in urinary arsenic profiles, following chronic inorganic arsenic exposure, is well-known in humans. To understand this variability, we studied the relationship between polymorphisms in the gene for human monomethylarsonic acid (MMA(V)) reductase/hGSTO1 and the urinary arsenic profiles of individuals chronically exposed to arsenic in their drinking water. To ensure that we did not overlook rare polymorphisms, not included in the public databases, we amplified and sequenced all six exons of the gene and their flanking regions, using DNA isolated from peripheral blood samples of 75 subjects, living in the vicinity of Torreon, Mexico. Four groups, based on the levels of arsenic (9-100 microg/L) in their drinking water, were studied. We identified six novel polymorphisms and two reported previously. The novel polymorphisms were a three base pair deletion (delGGC) in the first intron; a G > C transversion, leading to a serine-to-cysteine substitution at amino acid 86; a G > T transversion and a A > T transversion in intron 5; a G > A transition resulting in glutamate-to-lysine substitution in amino acid 208; and a C > T transition producing an alanine-to-valine substitution in amino acid 236. Two subjects displayed significant differences in patterns of urinary arsenic; they had increased levels of urinary inorganic arsenic and reduced levels of methylated urinary arsenic species as compared to the rest of the study population. These two subjects had the same unique polymorphisms in hGSTO1 in that they were heterozygous for E155del and Glu208Lys. The identified SNPs may be one of the reasons for the large interindividual variability in the response of humans to chronic inorganic arsenic exposure. The findings suggest the need for further studies to identify unambiguously specific polymorphisms that may account for interindividual variability in the human response to chronic inorganic arsenic exposure.  相似文献   
100.
The posterior capsule opacification (PCO) is a frequent complication in the modern cataract surgery, uncomfortable for the patient and expensive for the health care system. According to prof. Apple, the main health care expenditure in U.S. is represented by cataract surgery, laser capsulotomy for PCO ranking next. Under these circumstances, it is not surprising that the lens bag pathology and the prevention of aftercataract hold the attention of many research groups all over the world. This paper is a literature review of the last 15 years, presenting the data we have considered to be the most significant.  相似文献   
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