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991.
Testicular germ cell tumour is said to be a model for curable neoplasm. However, the prognosis of primary extragonadal germ cell tumour does not appear to be as promising. Though similar in histology, the biology of primary extragonadal germ cell tumour is different as exemplified by the patients in this review. Eight patients with primary mediastinal germ cell tumours were treated with intensive cisplatin-based chemotherapy. All, except one, had non-seminomatous components. The poor prognosis of mediastinal germ cell tumour is due to a combination of poor treatment results with the cisplatin-based regimen and the development of non-germ cell and haematological malignancies.  相似文献   
992.
Tuberculosis of the cervical spine is rare, comprising 3-5% of cases of tuberculosis of the spine. Eight patients with tuberculosis of the cervical spine seen during 1989-1992 were reviewed. They all presented with neck pain. The 4 children presented with a kyphotic deformity. In all the children the disease was extensive, with a large prevertebral abscess formation, while in the adults it was localised to one or two motion segments. Cord compression was present in 4 of the 8 patients. All the patients were treated with antituberculosis drugs and 6 underwent surgery. There was full neurological recovery in all patients. The kyphosis was improved though not fully corrected. There was a problem in stabilisation of severe involvement of the body and dens of C2. Surgery seems to play a major role in the treatment of tuberculosis of the cervical spine.  相似文献   
993.
Phosphorylation of Ser residues in the NH2-terminal extension unique to cardiac troponin I (cTnI) is known to occur through protein kinase A and to alter myofilament Ca2+ activation (Robertson, S. P., Johnson, J. D., Holroyde, M. J., Kranias, E. G., Potter, J. D., and Solaro, R. J. (1982) J. Biol. Chem. 257, 260-263). Yet, how the NH2-terminal extension may itself affect thin filament Ca2+ signaling is unknown. To approach this question we have used molecular cloning, mutagenesis, and bacterial synthesis of a full-length cTnI and a truncated mutant (cTnI/NH2) missing the 32 amino acids. Using reconstituted preparations we could show no differences between cTnI and cTnI/NH2 either in inhibition of actomyosin ATPase activity, in Ca(2+)-reversible inhibitory activity, or in the relation between pCa and Ca2+ binding to the regulatory site of cTnC at either pH 7.0 or 6.5. There were also no significant differences at either pH in the pCa-MgATPase activity relation of myofibrils into which the various species of TnI has been exchanged. Our results indicate: 1) that phosphorylation most likely induces a new state of TnI activity rather than altering an intrinsic effect of the NH2-terminal peptide on Ca2+ activation; and 2) that domains outside the NH2-terminal extension are important with regard to differences in effects of acidic pH on Ca2+ activation on cardiac and skeletal myofilaments.  相似文献   
994.
This paper discusses the utilization of MDC and DRG for the evaluation of the activities of surgical divisions. Discharge data on 1901 admissions of the second semester 1992 (97.1% of admissions) to three surgical divisions of ULSS 13 in Veneto Region were assigned to HCFA-DRG, 6th version: 423 (22.3%) in division A; 681 (35.8%) in B; 797 (41.9%) in C. MDC 6 (Diseases and Disorders of the Digestive System) was the most frequent MDC in every division; MDC 4 (Diseases and Disorders of the Respiratory System) had an high proportion only in division A, showing the peculiar feature of this division that effects the thoracic surgery of the whole ULSS. Division A had the highest proportion (56.3%) of admissions for surgical DRGs; division C the lowest (35.4%). DRG 119 (Vein Ligation and stripping) was the most frequent surgical DRG in every division: in the whole sample its DRG specific pre-surgical average length of stay was 1.7 days, and the total average length of stay was 4.7 days. MDC and DRG were usefull in describing case-mix, but it is fundamental to have an appropriate knowledge of these instruments, to avoid in reaching inappropriate considerations, because it was inappropriate the use of the same instruments.  相似文献   
995.
BACKGROUND/AIMS: Treatment with ursodeoxycholic acid has been shown to decrease the rate of disease progression in patients with primary biliary cirrhosis, although the effect is modest. Since primary biliary cirrhosis has many features of an autoimmune disorder, immunosuppressives added to ursodeoxycholic acid may be of value in the treatment of primary biliary cirrhosis. METHODS: A 1-year randomized, double-blind, placebo-controlled trial was carried out in 50 patients with primary biliary cirrhosis, who had already been treated with ursodeoxycholic acid for at least 1 year, but had not achieved complete disease remission. Patients were randomized to additional prednisone (30 mg per day initially, tapered to 10 mg daily after 8 weeks) and azathioprine (50 mg daily) or placebo. A subgroup of patients received cyclical etidronate and calcium. The principal aim of the study was to assess the short-term benefits and risks of the combined bile acid and low-dose immunosuppressive regimen. Primary endpoints were effects on symptoms, liver biochemistry, liver histology, bone mass and the occurrence of adverse events. RESULTS: Pruritus (p=0.02), alkaline phosphatase, aspartate aminotransferase, IgM and procollagen-III-propeptide improved significantly (all p<0.002) in the combined treatment group as compared to the placebo group. Histological scores for disease activity and disease stage decreased significantly within the combination treatment group (p<0.001). CONCLUSIONS: In patients with primary biliary cirrhosis receiving ursodeoxycholic acid, there is an additional beneficial effect of 1-year treatment with prednisone and azathioprine on symptoms and biochemical, fibrogenetic and histological parameters. These results strongly encourage the evaluation of this triple treatment regimen in long-term controlled trials of adequate size to document its effect on clinical events.  相似文献   
996.
Adult varicella can be a severe illness complicated by pneumonia, encephalitis, or prolonged fever. This study measured levels of tumor necrosis factor (TNF)-alpha, interleukin-2 (IL-2), and interferon gamma (IFN-G) in a consecutive group of 31 adult varicella patients presenting within 24 hours of rash onset. All cytokines were assayed using an ELISA technique. TNF-alpha was detectable in 71% of patients with a mean level of 52 pg/ml. IL-2 was detectable in 29% with a mean level of 1040 pg/ml. IFN-gamma was detectable in only 9%. There was no correlation between TNF, IL-2, or IFN-G level and clinical severity as determined by duration and severity of cutaneous findings, duration of fever, frequency of hepatitis, or thrombocytopenia.  相似文献   
997.
An isoform of starch synthase from potato tubers which is present both in the stroma of the plastid and tightly bound to starch granules has been identified biochemically and a cDNA has been isolated. The protein encoded by the cDNA is 79.9 kDa and has a putative transit peptide and a distinct N-terminal domain which is predicted to be highly flexible. It is similar in both amino acid sequence and predicted structure to the granule-bound starch synthase II (GBSSII) of pea embryos. When expressed in Escherichia coli, the mature protein has starch synthase activity. The importance of the isoform has been assessed by biochemical measurements and antisense transformation experiments in which the amount of the isoform in the tuber is severely and specifically reduced. Both approaches indicate that the isoform contributes a maximum of 15% of the total starch synthase activity of the tuber. It is suggested that this isoform and the GBSSII of pea embryos represent a widely distributed class of isoforms of starch synthase. The contribution to total starch synthase activity of members of this class probably varies considerably from one type of storage organ to another.  相似文献   
998.
In order to assess environmentally and occupationally related exposures to PAH compounds it is essential to have reference or normal values in human body fluids. The establishment of reliable reference intervals is an absolute pre-requisite in determining relationships between internal PAH exposure in humans and health effects in occupationally exposed workers. In this context the estimation of the biological level of PAH metabolites in urine from reference populations has become increasingly important in the field of environmental and occupational toxicology. The present study describes the calculation of tentative reference values for urinary 1-hydroxypyrene on the basis of two reference populations and for urinary alpha-naphthol on the basis of one reference population in accordance with IFCC recommendations. The study subjects were 115 healthy male workers occupationally exposed to PAH at low levels and 121 reference subjects non-occupationally exposed to PAH. Tentative reference values for urinary 1-hydroxypyrene were estimated. In addition, 236 healthy male workers were used to estimate tentative reference values for urinary alpha-naphthol. The reference populations were described by distribution free one-sided tolerance intervals. The 95% one-sided tolerance limit calculated for 1-hydroxypyrene in urine was 0.053 mumol/mol creatinine for non-occupationally exposed individuals and 0.169 mumol/mol creatinine for low level PAH exposed workers, with the coverage interval (95 +/- 4.5) percent at a probability of 0.95. Thus, the probability was 0.975 that the tolerance interval included at least 90.5% of the distribution. In addition, the probability was 0.025 that the tolerance interval included > 99.5% of the population. The tolerance interval for alpha-naphthol in urine was 5.665 mumol/mol creatinine with the coverage interval (95 +/- 4.5) percent at a probability of 0.95.  相似文献   
999.
Dietary risk factors for renal cell cancer were investigated in a population based case-control study of incident cases. A total of 351 cases and 340 controls matched for age and sex were interviewed about dietary habits as well as exposure to other known or suspected risk factors. An association was found between risk of renal cell cancer and energy intake, especially fats. There was no protective effect of fruits but a weak protective effect of cruceferous vegetables. The association with diet was present after adjusting for the effect of cigarette smoking, socioeconomic status and body mass index, all of which have been identified as risk factors for renal cell cancer.  相似文献   
1000.
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