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31.
Experiments were designed to distinguish between central and peripheral effects on temperature preference and body temperature of drugs injected intraperitoneally (IP) in infant mice ranging in age from 3 to 10 days postpartum. These compared a drug restricted to the periphery ("peripheral" drug) with a drug of similar action that reaches the central nervous system (CNS) as well as the periphery. Two different classes of drugs were utilized to test central versus peripheral actions independently with drugs that have different modes of action: 1-aromatic amino acid inhibitors and serotonin receptor antagonists. Although the decarboxylase inhibitor NSD 1015, which reaches the central nervous system from IP injection, can significantly decrease temperature preference (Tpref), the peripheral inhibitor carbidopa had no significant effects on Tpref or on body temperature (Tb). Furthermore, pretreatment with NSD 1015 prevented the elevation of Tpref produced by the serotonin precursor 5-hydroxytryptophan (5-HTP); however carbidopa pretreatment had no effect on the increased Tpref produced by 5-HTP. In other experiments, the peripheral serotonin antagonist BW 501C was not able to prevent elevated Tpref produced by 5-HTP, although the specific 5-HT2 antagonist pirenperone, which reaches the CNS as well as the periphery, blocks the 5-HTP elevation of Tpref. Taking all of these results together, we conclude that the changes in Tb and Tpref following these treatments require a decarboxylase inhibitor or 5-HT antagonist that reaches the CNS. However, the well known and potent peripheral vasoconstrictor action of serotonin requires that peripheral effects of drugs be considered when manipulations are not restricted to the CNS.  相似文献   
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We present a 16-year-old boy with weakness, hypercortisolemia, and markedly elevated adrenocorticotropic hormone. Computed tomographic imaging revealed hepatic lesions and a calcified pancreatic mass. Biopsy of the hepatic lesions revealed moderately differentiated neuroendocrine carcinoma. The primary tumor could not be determined. The patient received neoadjuvant chemotherapy with carboplatin and etoposide followed by therapeutic bilateral adrenalectomy and tumor debulking. Despite significant clinical improvement, restaging revealed progressive hepatic disease. The patient died 9 months after diagnosis. Autopsy revealed disseminated neuroendocrine carcinoma. The rarity of this tumor compels a cooperative investigational model involving pediatric and adult oncologists.  相似文献   
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Context.-We investigated expression of the adhesion molecule CD31 in sinus histiocytosis with massive lymphadenopathy (SHML) and Langerhans cell histiocytosis (LCH) because (1) SHML and LCH cells express a variety of cellular adhesion molecules and (2) SHML has been characterized as a reactive histiocytic proliferation, and tissue macrophages (histiocytes) are known to express CD31. Objective.-The purpose of this study was to determine whether SHML and LCH cells express CD31 and whether dual staining with CD31 and S100 facilitates diagnosis of these disease states. Methods.-Formalin-fixed, paraffin-embedded archival tissues were immunohistochemically stained via the labeled streptavidin-biotin method using antibodies against CD31 and S100 protein after heat-induced epitope retrieval. Archival tissues included SHML (n = 2), LCH (n = 10), malignant melanoma (n = 5), sinus hyperplasia (n = 4), granulomas (n = 4), granular cell tumor (n = 6), and normal skin (n = 4). Results.-Normal Langerhans cells in the epidermis were CD31(-)/S100(+); neoplastic Langerhans cells in LCH were CD31(+)/S100(+). Histiocytes in granulomas and in sinus hyperplasia were CD31(+)/S100(-); abnormal histiocytes in SHML were CD31(+)/S100(+). S100(+) tumors (malignant melanoma and granular cell tumor) were CD31(-). Conclusions.-The spectrum of cell types that express CD31 is expanded to include SHML and LCH. We speculate that up-regulation of CD31 in neoplastic Langerhans cells contributes to the migratory capability of LCH cells. CD31 may be a useful nonlysosomal marker of macrophages and their neoplastic counterparts (true histiocytic sarcomas). An immunohistochemical staining panel that includes CD31 and S100 facilitates the diagnosis of SHML and LCH.  相似文献   
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Journal of Neuro-Oncology - Brain tumor treatment and survival information is generally limited in large-scale cancer datasets. We provide a clinical investigation of current patterns of care and...  相似文献   
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BACKGROUND: Schistosomal infections of the female reproductive tract are common in countries where the parasite is endemic. Serious complications, such as ectopic pregnancy and infertility, may arise in patients with gynecologic schistosomiasis. CASE: A primiparous, African woman presented with vaginal bleeding and was found to have an ectopic pregnancy. Laparoscopy revealed distorted pelvic anatomy due to dense adhesions. Pathologic examination confirmed an ectopic pregnancy and identified Schistosoma haematobium ova in the patient's fallopian tube. Urine examination was confirmatory, and the patient was treated and referred for fertility counseling. CONCLUSION: Clinicians should consider schistosomiasis as a possible etiology for gynecologic complaints, including serious complications such as ectopic pregnancy and infertility, in patients from endemic regions.  相似文献   
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Analyses were conducted to estimate lifetime and current prevalence of major depressive disorder (MDD) for four representative cities of Mexico, to identify variables that influence the probability of MDD, and to further describe depression in Mexican culture. A multistage probability sampling design was used to draw a sample of 2,509 adults in four different regions of Mexico. MDD was assessed according to DSM-IV criteria by using the Composite International Diagnostic Interview collected by trained lay interviewers. The prevalence of MDD in these four cities averaged 12.8% for lifetime and 6.1% for the previous 12 months. MDD was highly comorbid with other mental disorders. Women were more likely to have lifetime MDD than were men. Being divorced, separated, or widowed (compared to married or never married) and having experienced childhood trauma were related to higher lifetime prevalence but not to current prevalence. In addition, age and education level were related to current 12-month MDD. Data on the profile of MDD in urban Mexico are provided. This research expands our understanding of MDD across cultures.  相似文献   
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The incidence of esophageal adenocarcinoma in humans is increasing more rapidly than any other malignancy in the United States. Animal studies have demonstrated the efficacy of freeze-dried berry supplementation on carcinogen-induced esophageal squamous cell carcinoma in rats; however, no such studies have been done in esophagoduodenal anastomosis (EDA), an animal model for reflux-induced esophageal adenocarcinoma (EAC) development. Eight-week-old male Sprague-Dawley rats were randomized into 3 groups: EDA + control diet (EDA-CD; n = 10); EDA + 2.5% black raspberry diet (EDA-BRB; n = 11) and EDA + 2.5% blueberry diet (EDA-BB; n = 12). After 2 wk of feeding the respective diets, the rats underwent EDA surgery to induce gastroesophageal reflux and then continued the diet. Measurement of feed intake suggested that all EDA-operated animals had lower feed intake starting at 10 wk after surgery and this was significant close to termination at 24 wk. There were no significant differences in either reflux esophagitis (RE), intestinal metaplasia (IM) (70% in CD, 64% in BRB, and 66% in BB; P = 0.1) or EAC incidence (30% for CD, 34% for BRB, and 25% for BB; P = 0.2) with supplementation. Berry diets did not alter COX-2 levels, but BB diet significantly reduced MnSOD levels (1.23 ± 0.2) compared to control diet (2.05 ± 0.14; P < 0.05). We conclude that a dietary supplementation of freeze-dried BRB and BB at 2.5% (w/w) was not effective in the prevention of reflux-induced esophageal adenocarcinoma in this EDA animal model.  相似文献   
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