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961.
Miura H  Taira O  Hiraguri S  Maeda J  Kato H 《Surgery today》2002,32(10):891-895
Squamous cell carcinoma of the breast is a rare type of cancer, the origin of which is still uncertain. We report a case of squamous cell carcinoma of the breast with a recurrent tumor that showed undifferentiated features. The patient was a 55-year-old woman who originally presented with a left breast mass in the upper outer quadrant. Echography showed a 46 × 29 × 23-mm mass with cavity formation, and aspiration cytology confirmed a diagnosis of squamous cell carcinoma. A modified radical mastectomy with level III lymph node dissection was performed. Pathologically, the tumor was composed of squamous cell carcinoma and noninvasive ductal carcinoma. A recurrent tumor showing undifferentiated features was detected in the left forechest 3 months after the operation, and tumorectomy with partial resection of the major and minor pectoralis muscles was performed. Despite intensive therapy including chemotherapy (CEF: cyclophosphamide, epirubicin, 5-fluorouracil) and irradiation (50 Gy), the patient died from pulmonary and skin metastases 20 months after her initial operation. The squamous cell carcinoma of the breast in this patient grew rapidly and her prognosis was poor. Immunohistochemical findings indicated the possibility that the squamous cell carcinoma developed from noninvasive ductal carcinoma of the comedo type, and that the undifferentiated cells from the site of recurrence developed from dedifferentiation of the squamous cell carcinoma. Received: August 10, 2001 / Accepted: March 5, 2002  相似文献   
962.
BACKGROUND: Use of the inferior mesenteric vein (IMV) for partial portal decompression has not been recommended as a first-line option for intractable gastroesophageal variceal bleeding because of the thin diameter of the vein. Although these indications remain relevant, few reports have compared partial portal decompression using the IMV with other therapies. We propose that partial portal decompression using the IMV is a useful alternative treatment for intractable variceal bleeding. METHODS: We performed partial portal decompression using the IMV in eight patients with intractable variceal bleeding that had been uncontrolled using medical and endoscopic therapies. All patients were classified into Child's class B or C. The surgical data, morbidity, and mortality were assessed. RESULTS: Mean portal venous pressure significantly decreased from 26.9 +/- 2.0 mmHg before the surgery to 19.8 +/- 3.9 mmHg after the surgery. The operative mortality rate was 0%. The mean duration of hospital stay was 25.5 +/- 13.3 days. Although one patient experienced recurrent bleeding, shunt patency was well maintained in all patients during the follow-up period (mean 28.9 +/- 14.1 months). Six patients are still alive and well without ascites or hepatic encephalopathy. Two of the Child's class C patients who underwent emergency shunt died owing to hepatic decompensation. CONCLUSION: Partial portal decompression using the IMV can be a safe, effective way to treat intractable variceal bleeding in patients with liver cirrhosis. However, use of the shunt procedure may have the most survival benefits for cirrhotic patients with preserved liver function.  相似文献   
963.

Background  

The aims of this study were to evaluate contemporary outcomes associated with the surgical management of pancreatic neuroendocrine tumors (PNETs) and to assess the prognostic value of the World Health Organization (WHO) classification and TNM staging for PNETs.  相似文献   
964.
Background Although extrahepatic metastasis occurs rarely after hepatic resection for hepatocellular carcinoma (HCC), the prognosis of these patients is extremely poor. Predictors of extrahepatic metastasis have not been fully investigated. Methods To identify predictors of extrahepatic metastasis after resection, we retrospectively investigated 77 patients with HCC tumors >50 mm in diameter who underwent hepatic resection. We investigated correlations between postoperative extrahepatic metastasis and clinicopathologic factors as well as extrahepatic metastasis-free survival rate by log rank test and predictors of extrahepatic metastasis by univariate and multivariate logistic regression models. Results Hepatitis B surface antigen (HBs-Ag) was found in 25 (32.5%) of 77 patients, and extrahepatic metastasis occurred in 26 (33.8%). Patients with extrahepatic metastasis showed better liver function and a high occurrence of HBs-Ag positivity than those without. The 5-year extrahepatic metastasis-free survival rate was worse in patients with HBs-Ag positivity, larger tumors (≥70 mm), higher alfa-fetoprotein level (≥300 ng/mL), and lower indocyanine green retention rate at 15 minutes (ICGR15) (<15%) than in those without. By univariate logistic regression analysis, HBs-Ag positivity, larger HCC tumor (≥70 mm), lower ICGR15 (<15%), and lower preoperative lymphocyte count (<1000/mm3) were predictors of extrahepatic metastasis (P < .1). By multivariate analysis, HBs-Ag positivity was an independent predictor of postoperative extrahepatic metastasis (P = .04). Conclusions In patients positive for HBs-Ag, radiologic examination of extrahepatic organs should be performed as a part of the postoperative surveillance. Hepatitis B virus infection may promote establishment of extrahepatic metastasis.  相似文献   
965.
966.
Metabolomics is one of the newer omics fields, and has enabled researchers to complement genomic and protein level analysis of disease with both semi-quantitative and quantitative metabolite levels, which are the chemical mediators that constitute a given phenotype. Over more than a decade, methodologies have advanced for both targeted (quantification of specific analytes) as well as untargeted metabolomics (biomarker discovery and global metabolite profiling). Untargeted metabolomics is especially useful when there is no a priori metabolic hypothesis. Liquid chromatography coupled to mass spectrometry (LC-MS) has been the preferred choice for untargeted metabolomics, given the versatility in metabolite coverage and sensitivity of these instruments. Resolving and profiling many hundreds to thousands of metabolites with varying chemical properties in a biological sample presents unique challenges, or pitfalls. In this review, we address the various obstacles and corrective measures available in four major aspects associated with an untargeted metabolomics experiment: (1) experimental design, (2) pre-analytical (sample collection and preparation), (3) analytical (chromatography and detection), and (4) post-analytical (data processing).  相似文献   
967.
968.
As a result of strong financial incentives created by the German parental leave reform on January 1, 2007, some 1000 births have been shifted from the last days of 2006 to the first days of 2007, especially by working mothers. This fact is already described in the literature, yet there is no evidence as to the mechanisms and only scarce evidence regarding the effects on newborn health. I use new data to study the timing of C-sections and the induction of births around the day the reform took effect. I estimate that postponed C-sections and inductions account for nearly 80 % of the pre-reform shortfall and nearly 90 % of the post-reform excess number of births. Despite concerns voiced by doctors before the reform, hardly any evidence can be found for detrimental health effects of those shifts, as measured by changes in gestational age, birth weight, APGAR scores, neonatal mortality, or hospitalization.  相似文献   
969.
An “unintended consequence” of marijuana legalization is the impact on the pediatric population. From prenatal exposure to unintentional childhood exposures, through concerns of adolescence abuse and marijuana use for medicinal indications in children, marijuana exposure can affect pediatric patients at every stage in childhood. Regardless of the stage or reason of exposure, concerns exist about short-term and long-term consequences in a child’s physical and mental health. The use of cannabidiol (CBD) may have some benefit for the treatment of epilepsy, but emphasis needs to be on rigorous clinical trials to evaluate efficacy and safety. As more states allow both medical and recreational marijuana, availability and prevalence of use will likely increase and more surveillance and research is needed to evaluate the consequences on the pediatric population.  相似文献   
970.
Previous studies have reported the adverse cognitive effects of high folate status in older individuals with vitamin B12 (VB12) deficiency. Thus, the aim of this study was to investigate how high serum folate and VB12 deficiency could collaboratively aggravate neuronal degeneration. In total, 146 older non-demented diabetic individuals with an average age of 75 ± 3.9 were recruited. VB12 deficiency and high folate status were based on high serum methylmalonic acid (MMA) concentrations (> 0.3 μmol/L) and the serum folate concentration being in the top tertile (> 31.4 nmol/L) respectively. Among these subjects, there were 20 with elevated MMA and high folate. The structural magnetic resonance imaging data of these subjects were analyzed by performing flexible factorial analysis with the “folate level” and “MMA level” added as main effects, and the interaction effect of folate and VB12 on brain volume was evaluated. The results showed significant gray matter atrophy of the right middle occipital gyrus and the opercular part of the inferior frontal gyrus in subjects with a simultaneous high folate status and VB12 deficiency. Together with previous observational studies on cognitive function, this study lends support to the notion that high serum folate concentrations in older people with VB12 deficiency may be associated with increased neurodegeneration..  相似文献   
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