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61.
Intra-operative hemorrhage is the main surgical risk during liver resections. Nowadays hepatectomies for large or posterior liver tumors close to the hepatocaval junction can benefit from total hepatic vascular exclusion (HVE) involving portal triad exclusion and clamping of the inferior vena cava (IVC) below and above the liver. Anatomical aspects of HVE have been studied in 64 subjects by segmental occlusive phlebographies of the IVC, injection of corrosive substances into the hepatocaval network, biometry of the retrohepatic IVC and serial sections of injected livers. A total HVE should exclude the right suprarenal and phrenic veins. Clamping of the suprahepatic IVC depends on the termination of the left inferior phrenic vein. Clamping of the subhepatic IVC must be retrohepatic: the right lobe of the liver has to be mobilized to free the right border of the retrohepatic IVC into which flows the right suprarenal vein 40 +/- 20 mm above the right renal vein and under the superior right hepatic vein. Both suprahepatic and retrohepatic clamps excluding the retrohepatic portion of the IVC (46.6 +/- 13 mm) and the hepatocaval junction should come in contact behind the IVC without overlapping.  相似文献   
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Centrosome amplification plays a key role in the origin of chromosomal instability during cancer development and progression. In this study, breast cancer cell lines with different p53 backgrounds were used to investigate the relationship between genotoxic stress, G(1)/S cell cycle checkpoint integrity, and the development of centrosome amplification. Introduction of DNA damage in the MCF-7 cell line by treatment with hydroxyurea (HU) or daunorubicin (DR) resulted in the arrest of both G(1)/S cell cycle progression and centriole duplication. In these cells, which carry functional p53, HU treatment also led to nuclear accumulation of p53 and p21(WAF1), retinoblastoma hypophosphorylation, and downregulation of cyclin A. MCF-7 cells carrying a recombinant dominant-negative p53 mutant (vMCF-7(DNp53)) exhibited a shortened G(1) phase of the cell cycle and retained a normal centrosome phenotype. However, these cells developed amplified centrosomes following HU treatment. The MDA-MB 231 cell line, which carries mutant p53 at both alleles, showed amplified centrosomes at the outset, and developed a hyperamplified centrosome phenotype following HU treatment. In cells carrying defective p53, the development of centrosome amplification also occurred following treatment with another DNA damaging agent, DR. Taken together, these findings demonstrate that loss of p53 function alone is not sufficient to drive centrosome amplification, but plays a critical role in this process following DNA damage through abrogation of the G(1)/S cell cycle checkpoint. Furthermore, these studies have important clinical implications because they suggest that breast cancers with compromised p53 function may develop centrosome amplification and consequent chromosomal instability following treatment with genotoxic anticancer drugs.  相似文献   
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This study investigated episodes of sadness, help seeking for episodes of sadness, and perceived treatment helpfulness among Latino/as. Specifically, we examined whether gender, ethnicity, and other socio-cultural variables predicted episodes of sadness, help seeking, and treatment helpfulness. Data were taken from the National Latino Asian American Study which included service use questions for episodes of sadness. We stratified the data by service provider and used multiple logistic regressions as analytic strategy. Latinas had higher rates of episodes of sadness than Latinos, and everyday discrimination was positively associated with sadness. Acculturation was associated with more help seeking. Puerto Ricans had the highest rates of help seeking, and Mexican-Americans the lowest. Discrimination was the strongest predictor of treatment helpfulness from any professional as individuals with discriminatory experiences found services less helpful. Interventions need to address cultural factors but more focus needs to be placed on policies that seek to eliminate inequalities.  相似文献   
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OBJECTIVE: To propose a protocol for minimizing medical complications associated with the use of cyproterone, medroxyprogesterone, and depot leuprolide to treat paraphilia. METHOD: Review of the relevant literature. RESULTS: Certain patient populations should not be treated with these medications, and medical complications associated with each can be detected early and avoided. CONCLUSIONS: For each drug, a series of screening tests prior to use and scheduled testing during use can minimize potential medical complications.  相似文献   
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Research on adolescent use of substances has long sought to understand the family factors that may be associated with use of different substances such as alcohol, tobacco and marijuana. However, scant attention has been focused on these questions in Latin American contexts, despite growing concerns about substance use among Latin American youth. Using data from a sample of 866 Chilean youth, we examined the relationship of family and neighborhood factors with youth substance abuse. We found that in a Latin American context access to substances is an important predictor of use, but that neighborhood effects differ for marijuana use as opposed to cigarettes or alcohol. Age of youth, family and peer relationships, and gender all play significant roles of substance use.The study findings provide additional evidence that the use of substances is complex whereby individual, family, and community influences must be considered jointly to prevent or reduce substance use among adolescents.  相似文献   
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A phase I study to evaluate heparinization of tunnelled subclavian catheters (TSC) was conducted in 42 patients who each had a TSC for chemotherapy. They were enrolled in the study from August 1994 to December 1995. The inclusion criteria were: age 18–70, no general anticoagulant treatment, TSC used only for chemotherapy, informed consent. Heparinization was performed at the end of each cycle and then at increasing intervals: 11, 13, 15, 17, 19, and 21 days. A 21-day interval was intended to mimic the suppression of heparinization between cycles. Heparinization was performed with a 250 IU/ml heparin solution. Anti-Xa activity was studied before each heparinization. For each interval, at least 5 patients were followed up for two cycles. If no blockages were present progression to the next step was authorized. If one blockage was observed 5 additional patients were required to have their TSCs heparinized after the same interval. Two blockages (block) after the same interval meant that the previous interval was recorded as the longest tolerable. There were no blocks with the 11-day interval (6 patients), 1 block after 13 days (10 patients), 1 block after 15 days (10 patients), and no blocks after 17 days (5 patients), 19 days (6 patients), or 21 days (5 patients). The median anti-Xa activity (curative rate 0.2–0.6) was, respectively 11 days 6.74; 13 days 5.47; 15 days 4.71; 17 days 3.61; 19 days 3.67; 21 days 5.10 (NS). Heparinization between two cycles of chemotherapy is unnecessary. A high level of heparin activity persisted constantly inside the catheter lumen through the 3-week observation period.  相似文献   
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