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1.
Ziprasidone is an atypical antipsychotic with a unique receptor-binding profile. Currently, ziprasidone is approved by the US Food and Drug Administration for the acute treatment of psychosis in schizophrenia and mania in bipolar disorder. When compared to certain other atypical antipsychotics, ziprasidone appears to have a relatively benign side effect profile, especially as regards metabolic effects eg, weight gain, serum lipid elevations and glucose dysregulation. Taken together, these data suggest that ziprasidone may be a first line treatment for patients with bipolar mania. However, ziprasidone is a relatively new medication for which adverse events after long-term use and/or in vulnerable patient populations must be studied. Unstudied areas of particular importance include the efficacy and safety of ziprasidone in the treatment of bipolar depression and relapse prevention of mania as, well as in the subpopulations of pregnant women, the elderly and pediatric patients. The emergence of mania in patients taking ziprasidone is another topic for further study.  相似文献   
2.
Tamoxifen has been implicated as a risk factor for venous thrombosis in advanced breast cancer although the evidence for increased arterial or venous thrombosis with tamoxifen in early breast cancer is less clear. The effect of tamoxifen on haemostasis, and thereby possible thromboembolic risk, was investigated in normal women enrolled in a placebo controlled trial of tamoxifen as a chemopreventative agent for breast cancer. There was an initial reduction in fibrinogen levels in all women on tamoxifen over the first year of follow-up and a marginal reduction in antithrombin III and Protein S in postmenopausal women at 6 months. There were no changes in cross linked fibrinogen degradation products or Protein C for pre or post-menopausal women. There was no increase in the incidence of thromboembolic events on tamoxifen. This study demonstrates that tamoxifen has only marginal effects on factors involved in haemostasis reported to affect the incidence of arterial or venous thromboembolic disease. The follow-up time is relatively short (maximum 36 months) and careful long term follow-up is necessary to detect clinically significant morbidity.  相似文献   
3.
A lump on the midface of a child can pose as a diagnostic dilemma. There is a wide variety of possible differential diagnoses, ranging from simple benign conditions such as a sebaceous cyst, dermoid cyst, lipoma, neuroma and neurofibroma, to potentially devastating conditions such as odontogenic myxoma.A case of a child in which the formulation of a definite diagnosis was clinically and histologically challenging is presented.  相似文献   
4.
Histological examination of the metastatic rat mammary adenocarcinoma line MTLn3 showed that macrophages and mast cells were frequently localized at the tumor periphery in the stromal tissues adjacent to the zones of tumor invasion. The interactions of these host cells with tumor cells and tumor-associated fibroblasts could be important in stimulating the production of extracellular matrix-degrading enzymes that facilitate tumor invasion and metastatic spread. Therefore, we examined the effects of isolated, activated macrophages and mast cells on the secretion of collagenolytic activities by normal fibroblasts, metastatic mammary adenocarcinoma cells and tumor-associated fibroblasts. Medium from activated macrophages or degranulated mast cells stimulated significant increases in production of collagenolytic activities by normal and tumor-associated fibroblasts and MTLn3 tumor cells. Medium from activated macrophages that had been pretreated with medium from degranulated mast cells, however, were less stimulatory to fibroblasts and tumor cell production of collagenolytic activities than medium from degranulated mast cells alone. We also examined the effects of two cytokines, interleukin-1 and tumor necrosis factor-a on activated macrophage- and degranulated mast cell-stimulation of fibroblast and tumor cell collagenolytic activities. The two cytokines alone or in combination stimulated increased production of collagenolytic activities by fibroblasts and tumor cells. Addition of the cytokines to degranulated mast cell products resulted in secretion of higher collagenolytic enzyme activities by normal fibroblasts (but not by tumor-derived fibroblasts or tumor cells) than with degranulated mast cell product-treatment of either target cell alone. Cytokines used in combination with macrophage-conditioned medium were less effective in stimulating fibroblast and tumor cell collagenase activities than cytokines alone. Thus normal infiltrating host cells such as macrophages and mast cells can have profound effects on the production of degradative enzymes by tumor cells and tumor-associated stromal fibroblasts.  相似文献   
5.
The zebrafish (Danio rerio) possesses two mechanosensory organs believed to be homologous to each other: the inner ear, which is responsible for the senses of audition and equilibrium, and the lateral line organ, which is involved in the detection of water movements. Eight zebrafish circler or auditory/vestibular mutants appear to have defects specific to sensory hair cell function. The circler genes may therefore encode components of the mechanotransduction apparatus and/or be the orthologous counterparts of the genes underlying human hereditary deafness. In this report, we show that the phenotype of the circler mutant, mariner, is due to mutations in the gene encoding Myosin VIIA, an unconventional myosin which is expressed in sensory hair cells and is responsible for various types of hearing disorder in humans, namely Usher 1B syndrome, DFNB2 and DFNA11. Our analysis of the fine structure of hair bundles in the mariner mutants suggests that a missense mutation within the C-terminal FERM domain of the tail of Myosin VIIA has the potential to dissociate the two different functions of the protein in hair bundle integrity and apical endocytosis. Notably, mariner sensory hair cells display morphological and functional defects that are similar to those present in mouse shaker-1 hair cells which are defective in Myosin VIIA. Thus, this study demonstrates the striking conservation of the function of Myosin VIIA throughout vertebrate evolution and establishes mariner as the first fish model for human hereditary deafness.  相似文献   
6.
This focus group, qualitative study (N = 18) reports the psychosocial impact, specifically, of spasticity symptoms on a sample of people with MS (multiple sclerosis). MS, a chronic disabling disease which attacks the central nervous system, currently affects about 100,000 people in the UK and estimates indicate that worldwide prevalence varies from around 10 to 250 per 100,000. The cause remains unknown and the rate of disease progression varies among individuals. The disease of MS itself has a severe impact on psychological well-being and quality of life. However, there is little evidence about the additional impact of the spasticity-related symptoms, which include involuntary muscle contractions, loss of dexterity, loss of balance, incontinence and pain. These are shown here to lead to further distress and embarrassment and to have a detrimental influence on emotional and social relationships.  相似文献   
7.
Neurotrophins (NT), such as nerve growth factor (NGF), stimulate the growth and differentiation of several neuronal subpopulations in a distinct yet overlapping manner. Brain-metastatic human melanoma cells overexpress p75(NTR), the low-affinity neurotrophin receptor, and treatment of brain-metastatic cells with NGF stimulates extracellular matrix invasion and production of degradative enzymes in relation to the cellular expression of p75(NTR) Although human melanoma cells express high affinity neurotrophin receptors, such as TrkC (the putative receptor for NT-3), they do not express TrkA, the high-affinity NGF receptor. Using digoxigenin-labeled sense/antisense riboprobes against human p75(NTR) and NGF for in situ hybridization, we determined whether the expression of p75(NTR) and NGF mRNAs are related to brain metastasis of human melanoma. We detected p75(NTR) mRNA at the invasion front of human melanoma brain metastases, whereas p75(NTR) expression was not found in adjacent tissues. In contrast, human NGF mRNA levels were increased in tissues surrounding the melanoma lesions, supporting the notion that NGF and NT are important in determining melanoma brain-metastatic microenvironment. Using antibodies specific to p75(NTR), TrkC, NGF and related NT we found high but heterogeneous levels of p75(NTR) and TrkC expression in malignant melanomas metastatic to the brain. Lower levels of expression were found in primary melanomas or in metastatic melanomas to sites other than brain. Additionally, we found elevated levels of synthesis of NGF and NT-3 but not brain-derived neurotrophic factor (BDNF) or NT-4/5 in the brain tissues surrounding melanoma lesions. These studies support a role for NT and their receptors in the progression of melanomas to the brain-metastatic phenotype.  相似文献   
8.
OBJECTIVE: As both premorbid neurodevelopmental impairments and familial risk factors for schizophrenia are prominent in childhood-onset cases (with onset of psychosis by age 12), their relationship was examined. METHOD: Premorbid language, motor, and social impairments were assessed in a cohort of 49 patients with childhood-onset schizophrenia. Familial loading for schizophrenia spectrum disorders, familial eye-tracking dysfunction, and obstetrical complications were assessed without knowledge of premorbid abnormalities and were compared in the patients with and without developmental impairments. RESULTS: Over one-half of the patients in this group had developmental dysfunction in each domain assessed. The patients with premorbid speech and language impairments had higher familial loading scores for schizophrenia spectrum disorders and more obstetrical complications, and their relatives had worse smooth-pursuit eye movements. The boys had more premorbid motor abnormalities, but early language and social impairments did not differ significantly between genders. There were no other significant relationships between premorbid social or motor abnormalities and the risk factors assessed here. CONCLUSIONS: Premorbid developmental impairments are common in childhood-onset schizophrenia. The rates of three risk factors for schizophrenia (familial loading for schizophrenia spectrum disorders, familial eye-tracking dysfunction, and obstetrical complications) were increased for the probands with premorbid speech and language impairments, suggesting that the pathophysiology of schizophrenia involves the abnormal development of language-related brain regions.  相似文献   
9.
MVP chemotherapy (mitomycin C 8 mg m(-2), courses 1, 2, 4 and 6, vinblastine 6 mg m(-2), cisplatin 50 mg m(-2)) is an active low-toxicity regimen in non-small-cell lung cancer (NSCLC). Based on the single-agent activity of these agents in SCLC, we have conducted a phase II trial of MVP in SCLC. Fifty chemo-naive patients with SCLC were entered in this trial. There were 33 men and 17 women with median age 66 years (range 46-83 years); 18 patients had limited disease (LD) and 32 extensive disease (ED). WHO performance status (PS) was: three patients PS 0, 33 patients PS 1, ten patients PS 2, four patients PS 3. A maximum of six cycles was given in responding patients. On completion of chemotherapy, patients with LD obtaining complete response (CR)/good partial response (PR) received thoracic irradiation and those obtaining CR were offered entry into the ongoing MRC Prophylactic Cranial Irradiation Trial. The overall response was 79% with 17% CR and 62% PR. For LD patients, 38% obtained CR but for ED only one patient achieved CR. Median response duration for LD patients was 8 months and for ED patients 5 months. Median survival was 10 months for LD patients and 6 months for ED patients. There was complete resolution of symptoms in 24%, partial improvement in 68%, no change in 2% and progressive symptoms in 6%. As regards toxicity, 24% developed WHO grade 3/4 neutropenia, 16% grade 3/4 thrombocytopenia and 6% significant hair loss. Two patients died during the first week of treatment with neutropenic infection. Quality of life using the EORTC questionnaire (QLC-C30) with lung cancer module demonstrated significant improvements from baseline levels in emotional and cognitive functioning, global QOL, of pain, dyspnoea and cough. MVP, an effective palliative regimen for NSCLC, is also active against SCLC with low toxicity and merits comparison with more toxic conventional schedules.  相似文献   
10.
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