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91.
Lower urinary tract obstruction in women is an uncommon condition resulting from multiple either organic or functional disorders. This paper contributes one case of obstructive uropathy secondary to presence of almost complete vulvar synechia due to extreme genital atrophy, a rare entity that may appear in postmenopausal women. Partial and incomplete vulvar fusion usually occurs in significant postmenopausal atrophies, sometimes associated to urethral meatus stricture; this, however, has no significant repercussion on urination dynamics. No other comparable case was found in the reviewed literature.  相似文献   
92.
We performed this case–control study to evaluate the risk of hypoglycemia associated with the use of antihypertensive drugs in older hospitalized diabetic patients treated with sulfonylureas and/or insulin. All diabetic patients admitted during 4 months in 1988, 1 month in 1991, 4 months in 1993 and 4 months in 1995 (n = 3477, mean age 71.4 ± 0.2 years, 1542 males and 1935 females) were enrolled in the study. During the four annual surveys 86 patients (mean age 71.1 ± 1.4 years, 33 males and 53 females) presented hypoglycemia during hospital stay. The patients who presented hypoglycemia were less frequently users of sulfonylureas and more frequently users of a combination of insulin and sulfonylureas. Use of antihypertensive drugs was similar in the two groups studied, and among potentially interacting drugs considered in the analysis, sulfonamides were more frequently used in patients who experienced hypoglycemia. Moreover, patients with hypoglycemia used a higher number of drugs, had a longer length of stay and had a greater prevalence of hypoglycemia as admission problem. Finally, although not significant, liver and renal diseases were more frequent among patients with hypoglycemia. In the multivariate analysis, contemporary use of insulin and sulfonylureas, liver disease and length of stay were significantly associated with hypoglycemia, while none of the antihypertensive drugs showed a significant association with the occurrence of hypoglycemia during hospital stay. Our results indicate that antihypertensive drugs do not increase the risk of hypoglycemia in elderly diabetic patients.  相似文献   
93.
Dieldrin, an organochlorine pesticide, has been shown to behepatocarcinogenic in mice but not rats. Phenobarbital, in contrast,induces hepatic tumors in both mice and rats. Previous studieshave shown that acute dietary exposure of rats or mice to eitherdieldrin or phenobarbital produces several liver changes, includingcentrilobular hypertrophy, induction of hepatic cytochrome P450,and increased liver weight. The present study examined the subchroniceffect of dieldrin (0.1, 1.0, 3.0, 10.0 mg dieldrin/kg diet)and phenobarbital (10, 50, 100, 500 mg phenobarbital/kg diet)on the induction of hepatic DNA synthesis and hepatocyte lethalityin male B6C3F1 mice and male F344 rats. Eight-week-old animalswere treated as above and evaluated for hepatic DNA synthesisafter 7, 14, 21, 28, and 90 days of continual treatment to dieldrinor phenobarbital. Maximal induction of hepatic DNA synthesisin mice was seen at the 14-, 21-, and 28-day sampling times.In rats, no significant increase in hepatic DNA synthesis orhepatocyte lethality was observed at any dose of dieldrin investigated.Phenobarbital produced a significant increase in hepatic DNAsynthesis in both rat and mouse liver following 7 days of treatment.The induction of DNA synthesis in rat liver was transient, withthe labeling index returning to control levels by 14 days oftreatment. In contrast, mice treated with phenobarbital showeda significant increase in hepatic DNA synthesis throughout thetreatment. In both mice and rats, dieldrin and phenobarbitalinduced hepatic DNA synthesis selectively in the centrilobularregion of the hepatic lobule. The lack of an increase in serumenzymes indicative of hepatic damage and the absence of liverhistopathology in mice or rats fed dieldrin or phenobarbitalindicate that the induction of DNA synthesis was not mediatedby a cytolethal, compensatory hyperplastic response, suggestinga mitogenic mechanism. Therefore, the species-specific inductionof hepatic DNA synthesis by either dieldrin or phenobarbitalcorrelated with the previously observed species-specific inductionof hepatic cancer by these two compounds.  相似文献   
94.
Chronic Marijuana Smoke Exposure in the Rhesus Monkey I. PlasmaCannabinoid and Blood Carbxyhemoglobin Concentrations and ClinicalChemistry Parameters SLIKKER, W., JR., PAULE, M. G., ALI, S.F., SCALLET, A. C., AND BAILEY, J. R (1991). Fundam. Appl Toxicol17, 321–334. This report is the first in a series abouta large multidisciplinary study designed to determine whetherchronic marijuana (MJ) smoke exposure results in residual behavioraland/or neuropathological alterations in the rhesus monkey. Priorto the initiation of a year of chronic MJ smoke exposure, 64periadolescent male rhesus monkeys were trained for 1 year toperform five operant behavioral tasks and then divided, accordingto their performance in these tasks, into four exposure groups(n=15–16/group): (1) a high dose (HI) group, exposed 7days/week to the smoke of one standard MJ cigarette; (2) a lowd m (LO) group, exposed on weekend days only to the smoke ofa standard MJ cigarate; (3) an extracted MJ cigarette (EX) group,exposed 7 days/week to the smoke of one ethanol-extracted MJcigarette; and (4) a sham group (SH), exposed 7 days/week tosham exposure conditions. Daily exposures for 1 year were accomplishedusing a mask that covered the subjects' nose and mouth. Averagebody weights (initially 3.7?0.5 kg, mean?SD) and rates of weightgain (approximately 0.1 kg/month) were the same for all groupsthroughout the entire experiment. During the first week of expsure,plasma concentrations of -9-tetrahydrocannabinol and 11-nor-9-carboxy-THCin the HI group were 59?7 (mean?SE) and 5.5?1.5 ng/ml, respectively,45 min after MJ smoke administration and did not change significantlyat similar times after exposure throughout the remainder ofthe year. Whole blood carboxyhemoglobin levels increased toapproximately 13% 1 min after expsure to smoke in either theMJ or the EX groups. Comparison of blood chemistry and hematologyvalues before, during, and after exposure indicated no differencesfor most parameters. During exposure, lymphocytes, alkalinephosphatase and -glutamyl transferase were depressed in theHI group compared to in the SH group. During exposure, aspartateaminotransferase was elevatd for both the HI and EX groups,suggesting a general effect of smoke exposure. Because theseeffects were transient and remained within the range of reportednormal values, these data indicate that long-term, experimentalexperimental exposure to MJ smoke is feasible and does not compromisethe general health of the rhesus monkey.  相似文献   
95.
Advanced stage ovarian cancer has a high rate of recurrence even after surgery followed by chemotherapy combining carboplatin and a taxane. New strategies are currently under way to combat this situation and one of the most promising ones is based on the knowledge that angiogenesis, the mechanism of formation of new blood vessels coupled with the degradation of the extracellular matrix for metalloproteinases, could be crucial in the development of this tumor. The principal molecule implicated in angiogenesis process of ovarian cancer is the vascular endothelial growth factor (VEGF). Several studies are now in progress to clarify its role as a diagnostic tool or its therapeutic implication. Presently, there is no indication for the use of VEGF in a preliminary diagnosis seeing that an increase in levels can be seen in both benign and malignant ovarian conditions. VEGF is also responsible for an increase in vascular permeability and is directly related to symptoms such as ascites and pleural effusion, both of which are frequent in ovarian cancer. Several papers have analised the role of VEGF as a prognostic factor and some of them do confirm VEGF as an independent prognostic factor in ovarian cancer. VEGF and the metalloproteinase system coupled with angiogenesis are currently being evaluated as therapeutic targets but no positive results have yet to be seen in this field.   相似文献   
96.
Loss of beta-catenin expression in metastatic gastric cancer.   总被引:10,自引:0,他引:10  
PURPOSE: Beta-catenin (beta-catenin) participates in intercellular adhesion and is an integral part of the Wnt signaling pathway. The role of beta-catenin in the pathogenesis of gastric cancer and its metastasis is largely unknown. PATIENTS AND METHODS: Immunohistochemistry and Western blot analysis were used to analyze the expression of beta-catenin in 87 human gastric cancers, in metastasis and cancer cell lines. The beta-catenin and the adenomatous polyposis coli (APC) genes were analyzed for gene mutations. Furthermore, methylation of the beta-catenin promoter in cell lines was assessed by treatment with 5'-azadeoxycytidine and sodium bisulfite genomic sequencing. RESULTS: beta-Catenin expression was present at either the cell membrane or the cytoplasm in 34 of 75 primary gastric cancers. Expression of beta-catenin was significantly more frequent in intestinal-type (P =.0049) and well-differentiated gastric cancers (P <.001). There were no quantitative differences between gastric cancers and the nonmalignant gastric tissues, as determined by Western blot analysis. One of 18 metastatic cancer lesions and four of five gastric cancer cell lines expressed beta-catenin protein. N87 cells, derived from the liver metastasis of a gastric cancer, did not express beta-catenin. Treatment with 5'-azadeoxycytidine restored beta-catenin protein levels in this cell line, which exhibited significantly more 5-methylcytosines in the beta-catenin promoter compared with the other cell lines. CONCLUSION: beta-Catenin expression is lost in a subgroup of primary gastric cancers, is frequently absent in metastases, and exhibits nuclear localization in cancers with either beta-catenin or APC gene mutations. Interestingly, the loss of beta-catenin expression in metastatic gastric cancers may result from hypermethylation of the beta-catenin promoter.  相似文献   
97.
We have developed a non-invasive method utilizing feces, containing sloughed colonocytes, as a sensitive technique for detecting diagnostic colonic biomarkers. In this study, we used the rat colon carcinogenesis model to determine if changes in fecal protein kinase C (PKC) expression have predictive value in monitoring the neoplastic process. Weanling rats were injected with saline or azoxymethane (AOM) and 36 weeks later fecal samples and mucosa were collected, poly A+ RNA isolated, and quantitative RT-PCR performed using primers to PKC betaII and zeta. Fecal PKC betaII and zeta mRNA levels were altered by the presence of a tumor, with tumor-bearing animals having a 3-fold higher (P < 0.05) PKC betaII expression as compared with animals without tumors. In addition, AOM-injection increased mucosal PKC betaII mRNA expression compared with saline controls. No effect of tumor incidence on mucosal PKC betaII expression was observed. In contrast, fecal PKC zeta expression was 2.5-fold lower (P < 0.05) in animals injected with azoxymethane versus saline. Since tumor incidence exerts a reciprocal effect on fecal PKC betaII and zeta mRNA expression, data were also expressed as the ratio between PKC betaII and zeta. The isozyme ratio was strongly related to tumor incidence, i.e. ratio for animals with tumors was 2.18 +/- 1.25, animals without tumors was 0.50 +/- 0.16, P = 0.025. We demonstrate that the expression of fecal PKC betaII and zeta may serve as a noninvasive marker for development of colon tumors. A sensitive technique for the detection of colon cancer is of importance since early diagnosis can substantially reduce mortality.   相似文献   
98.
Epilepsy surgery has emerged as an important option in the treatment of children with epilepsy that is refractory to antiepileptic drug management. The cornerstone of successful surgery is accurate localization of the brain region of seizure onset. Traditional techniques of seizure onset localization, e.g. surface electroencephalography (EEG) recording and magnetic resonance imaging (MRI), allow accurate localization in a significant number of patients. When the focus of seizure onset is not apparent from these non-invasive techniques, other methods of localization, e.g. intracranial EEG recording, may be needed before resection of the focus. Single-photon emission computed tomography (SPECT) is a nuclear medicine blood-flow technique that has been used to identify a region of epileptogenic brain associated with low blood flow in the resting state (interictal SPECT) or increased blood flow at the time of seizure activity (ictal SPECT). This report describes the validation and utility of a computer-assisted method of subtracting the interictal from the ictal SPECT scans and co-registering the difference image on the MRI. This method, called subtraction ictal SPECT co-registered on MRI (SISCOM), is used in guiding the location and the extent of intracranial electrode implantation, or in obviating the need for the implantation in some cases.  相似文献   
99.
100.
We aim to study the SCN5A gene in a cohort of Brugada syndrome (BS) patients and evaluate the genotype–phenotype correlation. BS is caused by mutations in up to 10 different genes, SCN5A being the most frequently involved. Large genomic rearrangements in SCN5A have been associated with conduction disease, but its prevalence in BS is unknown. Seventy‐six non‐related patients with BS were studied. Clinical characteristics and family risk profile were recorded. Direct sequencing and multiplex ligation‐dependent probe amplification (MLPA) of the SCN5A gene for identification of mutations and larger rearrangements were performed, respectively. Eight patients (10.5%) had point mutations (R27H, E901K, G1743R (detected in three families), V728I, N1443S and E1152X). Patients with mutations had a trend toward a higher proportion of spontaneous type I Brugada electrocardiogram (ECG) (87.5% vs 52.9%, p = 0.06) and had evidence of familial disease (62.5%, vs 23.5%, p = 0.03). The symptoms and risk profile of the carriers were not different from wild‐type probands. There were non‐significant differences in the prevalence of type I ECG, syncope and history of arrhythmia in carriers of selected polymorphisms. None of the patients had any deletion/duplication in the SCN5A gene. In conclusion, 10.5% of our patients had mutations in the SCN5A gene. Patients with mutations seemed to have more spontaneous type I ECG, but no differences in syncope or arrhythmic events compared with patients without mutations. Larger studies are needed to evaluate the role of polymorphisms in the SCN5A in the expression of the phenotype and prognosis. Large rearrangements were not identified in the SCN5A gene using the MLPA technique.  相似文献   
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