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141.
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143.
New Techniques and Agents in the Adjuvant Therapy of Pancreatic Cancer   总被引:1,自引:0,他引:1  
Pancreatic ductal adenocarcinoma represents a major oncological challenge. Despite improvements in surgical techniques, long-term survival after resection is poor, with few patients surviving after 5 years. Until recently, there have been no large randomized trials of adjuvant therapy in pancreatic ductal adenocarcinoma. However, major trials such as the European Study Group for Pancreatic Cancer (ESPAC-1) and ESPAC-3 trials have set new standards for patient recruitment and development in this field. Adjuvant therapy has the potential to improve both patient survival and quality of life after curative resection. Currently, the best treatment is with 5-fluorouracil with folinic acid, but in the light of ongoing clinical trials, this may be supplanted by gemcitabine as the treatment of choice. Chemoradiotherapy does not appear to be beneficial in the adjuvant setting, but trials of a wide variety of other techniques and agents in the treatment of advanced disease are being undertaken and some of these will almost certainly be extended into the adjuvant setting in time. Great progress has been made in the adjuvant treatment of pancreatic cancer in the past 10 years and similar advances are likely over the next decade.  相似文献   
144.
Forty-five children (28 girls and 17 boys; mean age 4.5 years) with hypothyroidism referred to us from January 1989 to November 1990 were evaluated prospectively for the pattern of hypothyroidism by hormone assays, scintiscan and urinary iodine estimation. Among the 6 children from non-endemic areas, athyreosis and/or hypoplasia were seen in 3, ectopia in 2 and dyshormonogenesis in 1. Of 39 children from moderate to severe environmentally iodine deficient regions, 18 (46%) had athyreosis and/or hypoplasia and 10 (26%) ectopic thyroid. Iodine deficiency was seen in 4, dyshormonogenesis in 4, secondary/tertiary hypothyroidism in 2 and thyroiditis in 1. The mean age of these children at the onset of symptoms was 1.4 years and at clinical presentation 4.5 years. There was significant growth retardation with 54% of children being below the 5th centile of Indian standards. There was no significant difference in the age at onset of symptoms and presentation, clinical features and bone age for the different types. The levels of serum total T4 were significantly low in dysgenesis (athyreosis, hypoplasia and ectopia, p < 0,001). Dysgenesis of the thyroid is the most common type of childhood hypothyroidism in iodine deficiency endemias. We postulate that severe iodine deficiency in the intrauterine and early neonatal period may lead to dysgenesis of the thyroid.  相似文献   
145.
Plasma interleukin-8 (IL-8) concentrations were measured in patients with atopic dermatitis. Plasma IL-8 was not detected in 25 controls (0/25), in allergic rhinitis (0/20), or in bronchial asthma during remission (0/13), while low concentrations of IL-8 were detectable in a few patients with urticaria (1/19), contact dermatitis (4/17), and bronchial asthma at the time of attack (6/16). In contrast, IL-8 was detectable in most cases of atopic dermatitis (41/52). Moreover, IL-8 concentrations were significantly higher in severe than in mild or moderate atopic dermatitis. IL-8 concentrations decreased as atopic dermatitis was improved by treatment, and IgE production in vitro was also decreased while serum IgE concentrations remained unchanged. IL-8 measurement may be a useful tool for the study of the pathogenesis and clinical course of atopic dermatitis.  相似文献   
146.
The mitochondrial DNA (mtDNA) mutation 8993 is an important cause of Leigh's encephalopathy. A family is reported where other affected members have presented with non-specific delayed development or cerebral palsy. The diagnosis should be considered not only in children with Leigh's encephalopathy, but also in those with mild neurological dysfunction (including cerebral palsy) if there is a pigmentary retinopathy or a family history of neurological or ophthalmological disease. There was some correlation in this family between the disease severity and the proportion of mutant mtDNA in the blood. This mutation appears to segregate to high levels of mutant mtDNA rapidly within pedigrees and the mother of a severely affected child has a high risk of having further children with a high proportion of mutant mtDNA and a severe phenotype.  相似文献   
147.
Abstract: Nurse-controlled analgesia (NCA) using a patient-controlled analgesia (PCA) device has been described for intensive care and postoperative use. This report describes the effective use of this technique for severe episodic and procedural pain in four children with advanced malignancy and high opioid requirements where conventional parenteral analgesia had been inadequate. Both morphine and fentanyl were used. Average duration of NCA was 6.75 days (range 4–12).  相似文献   
148.
Multiple sclerosis (MS) is a common neurological disease caused by genetic and environmental factors. Previous genetic analyses have suggested that theMHC/HLA region on chromosome 6p21 contains an MS- predisposing component. Which of the many genes present in this region is primarily responsible for disease susceptibility is still an open issue. In this study, we evaluated, in a large cohort of MS families from the Mediterranean island of Sardinia, the role of allelic variation at the HLA-DRB1, DQA1 and DQB1 candidate loci in MS predisposition. Using the transmission disequilibrium test (TDT), we found significant evidence of association with MS in both the Sardinian- specific DRB1*0405(DR4)- DQA1*0501-DQB1*0301 haplotype and the DRB1* 0301(DR3)-DQA1*0501-DQB1*0201 haplotype. Detailed comparative analysis of the DRB1-DQA1- DQB1 haplotypes present in this data set did not identify an individual locus that could explain MS susceptibility. The predisposing effect is haplotype specific, in that it is confined to specific combinations of alleles at the DRB1, DQA1 and DQB1 loci. Cross- ethnic comparison between the two HLA haplotypes associated with MS in Sardinians and the DRB1*1501 (DR2)-DQA1*0102-DQB1* 0602 haplotype, associated with MS in other Caucasian populations, failed to identify any shared epitopes in the DR and DQ molecules that segregated with disease susceptibility. These results suggest that another MHC gene(s), in linkage disequilibrium with specific HLA-DRB1, DQA1, DQB1 haploypes, might be primarily responsible for genetic susceptibility to MS. Alternatively, the presence of complex interactions between different HLA haplotypes, other non-HLA predisposing genes and environmental factors may explain different associations in different populations.   相似文献   
149.
The two most consistent features of the diseases caused by trinucleotide repeat expansion-neuropsychiatric symptoms and the phenomenon of genetic anticipation-may be present in forms of dementia, hereditary ataxia, Parkinsonism, bipolar affective disorder, schizophrenia and autism. To identify candidate genes for these disorders, we have screened human brain cDNA libraries for the presence of gene fragments containing polymorphic trinucleotide repeats. Here we report the cDNA cloning of CAGR1, originally detected in a retinal cDNA library. The 2743 bp cDNA contains a 1077 bp open reading frame encoding 359 amino acids. This amino acid sequence is homologous (56% amino acid identify and 81% amino acid conservation) to the Caenorhabditis elegans cell fate-determining protein mab-21. CAGR1 is expressed in several human tissues, most prominently in the cerebellum, as a message of approximately 3.0 kb. The gene was mapped to 13q13, just telomeric to D13S220. A 5'-untranslated CAG trinucleotide repeat is highly polymorphic, with repeat length ranging from six to 31 triplets and a heterozygosity of 87-88% in 684 chromosomes from several human populations. One allele from an individual with an atypical movement disorder and bipolar affective disorder type II contains 46 triplets, 15 triplets longer than any other allele detected. Though insufficient data are available to link the long repeat to this clinical phenotype, an expansion mutation of the CAGR1 repeat can be considered a candidate for the etiology of disorders with anticipation or developmental abnormalities, and particularly any such disorders linked to chromosome 13.   相似文献   
150.
Decline in blood CD4+ lymphocytes during primary symptomatic infections with HIV is usually attributed to viral killing, and has not been considered in terms of altered lymphocyte migration and sequestration. We therefore sought to examine whether CD4+ cell loss from blood of macaques undergoing an acute primary SIV infection might be due to increased synthesis of cytokines, known to profoundly affect lymphocyte trafficking, rather than to direct lymphocyte destruction by virus. The findings indicate that rapid lymphocyte depletion following acute infection is not selective for CD4+ cells, correlates precisely with increased plasma IFN-gamma and tumor necrosis factor-alpha levels, and is reversible. CD4/CD8 ratios in lymph nodes with high viral burdens remain relatively unchanged despite lymphocyte loss from blood. Levels of cytokine mRNA measured in lymphoid organs reflect neither cytokine plasma levels nor their potential to induce sequestration. These results support a model of cytokine-induced lymphocyte extravasation to account for the acute HIV/SIV-induced CD4+ cell lymphopenia and raise questions regarding the extent to which altered lymphocyte migration plays a role in the gradual CD4+ cell depletion throughout infection.   相似文献   
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