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排序方式: 共有3927条查询结果,搜索用时 125 毫秒
71.
Pramod Durgakeri Anamitra Sarkar Bianca Durgakeri 《The Australasian medical journal》2015,8(8):277-279
Sarcoma of the small bowel is an extremely rare type of small bowel malignancy and represents around 10 per cent of small bowel cancers. Usually asymptomatic, patients can present with chronic abdominal distention with pain and/or weight loss. Most pathologists now refer to small bowel sarcomas (SBS) as gastrointestinal stromal tumours as they are mesenchymal neoplasms believed to be derived from the interstitial cells of Cajal in the gastrointestinal tract. SBS can be highly vascular and commonly ulcerate and/or bleed. They tend to be aggressive and have a poor prognosis. Surgery is the treatment of choice for SBS, with definitive diagnosis usually made postoperatively with the aid of histopathology. We would like to highlight the importance of careful intra-operative examination of an unknown small bowel (SB) mass, which can give the surgeon clues to the type of tumour present. This case report aims to demonstrate this important process: recognising SBS intra-operatively will aid the surgeon with performing the appropriate resection as minute omental metastasis can be present with SBS; in such cases an omentectomy during the laparotomy is recommended. In institutions where available, intra-operative radiotherapy is ideal. 相似文献
72.
Metabolic Brain Disease - Metal homeostasis in the central nervous system (CNS) is a crucial component of healthy brain function, because metals serve as enzymatic cofactors and are key components... 相似文献
73.
Succinic dehydrogenase activity of the DMBA induced tumor explants cultured with or without hormones was assessed histochemically while receptors for estrogen (ER) and progesterone (PgR) were estimated from the cytosol fraction of the tumor tissue. Tumor regression following ovariectomy (OVX) was kept as the end point for determining hormone dependency. By in vitro method positive correlation was observed in 5 of 6 responsive or hormone dependent tumors, and 13 out of 14 independent tumors. Presence of receptors (ER + PgR, PgR) correlated with responsiveness in 4 of 6 tumors while their absence in the non-responsive group correlated in 6 of 14 tumors. Prolactin responsive tumors did not regress following OVX even if ER + PgR or ER/PgR were present. Using the same tumor tissue the results of hormone dependency by the two methods were identical in only 9 of 20 tumors. 相似文献
74.
75.
OBJECTIVE: The aim of this study was to summarize experiences of patients admitted to the intensive care unit (ICU) for an acute exacerbation of COPD and to identify factors associated with a poor outcome. METHODOLOGY: An observational case series of 102 consecutive admissions to the ICU for acute exacerbation of COPD between January 1998 and December 2002 were studied. RESULTS: In total, 102 admissions to the ICU were reviewed. There were no ICU deaths but there were 18 hospital deaths (18%). A total of 28 patients were treated with non-invasive positive pressure ventilation (NIPPV), of whom four (14% failure rate) subsequently required intubation and mechanical ventilation (MV). Another 16 patients (16%) were successfully weaned from MV with NIPPV. Nine patients (9%), who had more than one episode of re-intubation after weaning (RAW), were from the mechanically ventilated group. Tracheostomy was performed for four patients (3.9%). The median duration of both NIPPV and MV was 1 day. The median length of stay in the ICU and hospital were 2 days (SD, 7.2) and 8 days (SD, 9.6), respectively. Univariate analysis identified serum total protein to be associated with hospital mortality (P = 0.004) CONCLUSION: For patients with acute exacerbations of COPD in the ICU, serum total protein, a surrogate marker for nutrition, was significantly associated with hospital mortality. 相似文献
76.
Boivin G Lips P Ott SM Harper KD Sarkar S Pinette KV Meunier PJ 《The Journal of clinical endocrinology and metabolism》2003,88(9):4199-4205
Raloxifene has been shown to increase bone mineral density and reduce the risk of vertebral fracture in postmenopausal women with osteoporosis. In this study, we report the results of the first prospective longitudinal study to evaluate the mean degree of mineralization of bone (MDMB) in a group of patients enrolled in the Multiple Outcomes of Raloxifene Evaluation trial. Patients were randomly assigned to one of three treatment groups: placebo (n = 24), raloxifene 60 mg/d (RLX60; n = 22), or raloxifene 120 mg/d (RLX120; n = 18). All patients received daily calcium (500 mg) and vitamin D(3) (400-600 IU) supplementation for the duration of the study. Iliac crest biopsies were taken at baseline and after 2 yr of treatment. Quantitative microradiography was used to analyze the biopsy specimens and revealed a statistically significant (P < 0.05) mean percentage increase in total MDMB of 7.0, 5.3, and 5% for RLX60-, RLX120-, and placebo-treated patients, respectively, compared with baseline. Raloxifene treatment was found to shift the distribution of total bone mineral to higher values of MDMB (RLX60, 29%; RLX120, 8%) with greater heterogeneity, compared with placebo. The profile of MDMB observed in biopsies after treatment with placebo and raloxifene, compared with baseline, closely resembles physiological premenopausal bone. 相似文献
77.
Evidence for prolactin feedback actions on hypothalamic oxytocin, vasoactive intestinal peptide and dopamine secretion 总被引:2,自引:0,他引:2
D K Sarkar 《Neuroendocrinology》1989,49(5):520-524
Ovariectomized rats, when transplanted with 4 anterior pituitaries (APs) to the kidney capsule for 2-3 weeks, had elevated plasma prolactin (PRL) levels (3.8-fold) and showed decreased in situ AP weights (0.62-fold) and PRL concentrations (0.63-fold). The concentrations of dopamine (DA) and oxytocin (OT) in pituitary portal plasma of hyperprolactinemic rats were increased 1.7- and 1.9-fold, respectively. However, the levels of vasoactive intestinal peptide (VIP) in pituitary portal plasma of these rats were decreased 0.31-fold. The secretion of DA, dihydroxyphenylalanine (DOPA) and OT from fetal hypothalamic cells in primary culture was increased, whereas VIP secretion from these cells was reduced in a dose-dependent fashion following PRL treatment. These data are the first in vivo and in vitro demonstration of a stimulatory action of PRL on OT release and an inhibitory action of PRL on VIP release. Furthermore, these data suggest that a subtle imbalance between the secretion of the PRL-inhibiting factor (DA) and the PRL-releasing factors (VIP and OT) during elevated systemic levels of PRL is responsible for decreased lactotrophic function. 相似文献
78.
De A Boyadjieva N Oomizu S Sarkar DK 《Alcoholism, clinical and experimental research》2002,26(9):1420-1429
BACKGROUND: Alcohol drinking is known to cause hyperprolactinemia in both humans and laboratory animals. The mechanism by which alcoholism causes hyperprolactinemia is not known. This study investigated whether increased pituitary production of prolactin, which leads to alcohol-induced hyperprolactinemia, results from an increase in cell number and/or cell production of prolactin in the pituitary. METHODS: The effects of ethanol on lactotropes were determined in vivo using female rats as an animal model and in vitro using primary cultures of mixed rat anterior pituitary cells and enriched lactotropes. In vivo experiments involved administration of ethanol for 2 and 4 weeks using a liquid diet containing 8.7% ethanol (v/v), which provides 37% of the calories in cyclic, ovariectomized, and estradiol-17beta-treated ovariectomized Fischer-344 rats. The control group was pair-fed an isocaloric diet minus the ethanol or fed a normal diet ad libitum. These animals were used to determine ethanol's effects on plasma prolactin levels, pituitary wet weights, pituitary total protein levels, and the number of mitotic lactotropes. In vitro studies determined ethanol's effects in the presence and absence of estradiol on prolactin release and lactotropic cell proliferation. Prolactin levels in plasma and media samples were measured using radioimmunoassay. Mitotic lactotropes were determined using bromodeoxyuridine incorporation assay. RESULTS: Ethanol treatment increased in a time-dependent manner the plasma levels of prolactin in cyclic, ovariectomized, and estradiol-treated ovariectomized rats. Ethanol treatment also increased pituitary wet weight and/or pituitary total protein levels and DNA synthesis in lactotropes. Determination of ethanol's action on lactotropic cell proliferation and hormone secretion in vitro using primary cultures of mixed pituitary cells revealed that ethanol stimulated both basal and estradiol-induced prolactin secretion and lactotropic cell proliferation. When ethanol's actions were studied in isolated lactotropes, ethanol alone or in combination with estradiol stimulated prolactin secretion but failed to increase lactotropic cell proliferation. CONCLUSIONS: These results suggest that ethanol causes hyperprolactinemia by elevating prolactin release from lactotropes and by increasing the number of lactotropes in the anterior pituitary gland. The mitotic action of ethanol requires cell-cell communication between lactotropes and other pituitary cells. Furthermore, ethanol's mode of action on prolactin release and lactotrope growth is similar to that observed for estradiol. 相似文献
79.
80.
Cord blood samples collected from 150 newborns were tested for HBsAg using micro ELISA technique. Only 8 (5.3 per cent) out of 150 samples were found to be positive for HBsAg in variable titres. It is important to identify these HBsAg positive newborns so that appropriate measures could be adopted at the earliest to prevent the complications of HBsAg carriage. 相似文献