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1.
Trends in the incidence of non-epithelial cancers are particularly likely to reflect environmental carcinogens, since these malignancies are not commonly the targets of screening efforts, and have generally not been closely associated with life style factors such as cigarette smoking and diet. We used data from nation-wide cancer registries in Denmark, Finland, and Sweden to examine trends in non-epithelial cancers over the period 1961-1990. Linear regression analysis of age-standardized rates, and age-period-cohort models were fit to assess the temporal patterns within each country. Within each of the 3 countries, there was a similarly increasing incidence of both hematological malignancies and nervous system/bone/soft-tissue neoplasms. The increases were smallest in children and adolescents (ages 0-14), moderate among young and middle aged adults (ages 15-64), and most pronounced among the elderly (ages 65+). Age-period-cohort modeling suggested that the dominant factor in the increases were birth cohort effects. It is not clear what factors underlie this increase in incidence; it seems most likely that increases both in diagnostic efficiency and in exposure to environmental carcinogens play a role.  相似文献   

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The 16S rRNA gene sequences were determined for type strains of 21 Bifidobacterium species. A phylogenetic tree was constructed using the determined sequences and sequences from DNA databases, which contain the sequences of 11 type strains of Bifidobacterium species and 11 strains of related genera. All species of the genus Bifidobacterium and Gardnerella vaginalis ATCC 14018 belonged to a cluster phylogenetically distinct from the other genera. The cluster was divided into two subclusters: subcluster 1 composed of most species of Bifidobacterium and G. vaginalis, and subcluster 2 consisting of two species, B. denticolens and B. inopinatum; both of which were isolated from human dental caries. In the genus Bifidobacterium, four groups of species are known to be moderately to highly related by DNA-DNA hybridization. The four groups of species exhibited more than 99% similarity among their 16S rDNA sequences within each group. These results indicated that species with around 99% or more similarity in their 16S rDNA sequences should be confirmed for species identities.  相似文献   

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It has been proposed that NO may function as an endogenous cardioprotectant. We have investigated whether modulation of NO levels (detected in coronary effluent by chemiluminescence) by a blocker of its synthesis, by supplementation of its precursor, and by administration of an NO donor can influence reperfusion arrhythmias in the isolated rat heart. Rat hearts were perfused with modified Krebs' solution and subjected to 5, 35, or 60 minutes of left regional ischemia followed by 10 minutes of reperfusion. NG-Nitro-L-arginine methyl ester (L-NAME), which blocks NO synthase, increased the incidence of reperfusion-induced ventricular fibrillation (VF) from 5% in the control condition to 35% after 60 minutes of ischemia (n = 20, P < .05). The profibrillatory effect of L-NAME was prevented in hearts coperfused with 1 or 10 mmol/L L-arginine (an NO precursor) but persisted in hearts coperfused with D-arginine (1 mmol/L). L-NAME did not increase VF susceptibility in hearts reperfused after 5 or 35 minutes of ischemia. L-NAME caused sinus bradycardia (264 +/- 10 versus 309 +/- 5 bpm in control groups, P < .05) and reduced coronary flow before ischemia (6.2 +/- 0.6 versus 9.2 +/- 0.6 mL.min-1.g-1 tissue in controls, P < .05). L-NAME reduced coronary effluent NO levels after 60 minutes of ischemia; during the first minute of reperfusion, values were reduced from 1457 +/- 422 to 812 +/- 228 pmol.min-1.g-1 (P < .05). This effect was prevented by coperfusion with L-arginine (10,344 +/- 1730 pmol.min-1.g-1, P < .05).(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   

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The immunological therapy of cancer has been proposed in a number of neoplasms (Borden, Sondel, 1989; Foon, 1989; Rosenberg, 1992) and has recently been adopted in the treatment of Central Nervous System (CNS) tumors in combination with conventional surgical and radiotherapeutical approach. In this context, loco-regional administration of immunomodulating agents (for instance in post-surgical cavity) allows to achieve much higher in situ concentrations than by systemic route. Since these treatments have potential adverse effects, careful assessment of clinical and immunological parameters in phase I trials is needed. CNS tumors disseminating via Cerebrospinal Fluid (CSF) pathways offer a stimulating opportunity for intrathecal immunotherapy. In this context, alpha-IFN and IL2 (alone or in combination with LAK cells) have been employed either loco-regionally or intrathecally (Merchant, Mc Vicar, Merchant & Young, 1992; Schiller, Hank, Storer, Borchert, Moore, Albertini, Bechhofer, Wesley, Brown, Bastin & Sondel, 1993). The rationale for the use of both these substances includes the known anti-tumor action of alpha-IFN (Mahaley, Urso, Whaley, Blue, Williams, Guaspari & Selker, 1985; Nagai, 1988) and the ability of r-IL2 to generate activated cells effective in lysing tumor cell targets (Hayes, Moore, Pierz, Chen, Da Rosso, Nirenberg & Allen, 1993). We treated 3 patients (2 affected by disseminating cerebellar medulloblastoma, 1 by disseminating thalamic glioblastoma) by intrathecal r-IL2 via recervoir. In the first 2 patients, this treatment was preceded by alpha-IFN (also intrathecally). Monitoring of immunological effects of the treatment schedule involved kinetics of CSF and serum TNF-alpha, IL2s and IL2R during the first day of r-IL2 treatment, as well as on day +2 and +4 of both r-IL2 cycles, and assessment of CSF cells, protein and CSF and PB NK cell activity and CD3-CD56+ cells during the course of all treatment cycles. We also assessed clinical and neuroradiological effects of immunotherapy.  相似文献   

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The diversity of high voltage-activated (HVA) Ca2+ channels in rat CNS neurones was investigated with the nystatin perforated patch recording configuration. The neurones were freshly dissociated from rat substantia nigra, ventromedial hypothalamus, tuberomammillary nucleus, nucleus tractus solitarius, hippocampal CA1 region and cerebellum. Five different types of HVA Ca2+ channels were distinguished pharmacologically; dihydropyridine sensitive L-type, omega-conotoxin-GVIA sensitive N-type, omega-agatoxin-IVA sensitive P-type, omega-conotoxin-MVIIC sensitive Q-type, and R-type which is insensitive to these organic Ca2+ antagonists. The results showed clearly that the five subtypes of HVA Ca2+ channels differ considerably in their distribution among various CNS regions.  相似文献   

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The results of superselective intra-arterial chemotherapy with Mitomycin C (SIAC) in cases of hepatic neoplasms continue to be poor. Survival time was related to the percentage of hepatic replacement (PHR) but only 19% of the patients with Stage I tumours (PHR < 25%) survived for over 5 years and all the others died within 4 years. The patients with hepatic metastases from colorectal cancer achieved a significantly better cumulative 5-year survival figure than those with hepatocellular cancer (P < 0.05). The median survival times for patients with hepatic metastases from colorectal cancer, hepatocellular cancer and gallbladder cancer were 15 months, 6 months and 13 months, respectively. The overall response rate was only 27% (26/97), that for primary liver cancer 20% (7/35), that for hepatic metastases from colorectal cancer 22% (8/37) and that for gallbladder cancer 44% (11/25) and the patients who responded to SIAC (n = 27) had a significantly better cumulative 5-year survival rate (P < 0.005). Cessation of SIAC was necessary in 74% (72/97) of the cases, because of tumour progression in 53% (51/97), major complications in 19% (18/97) and patient refusal in 3% (3/97). The results of this trial may be regarded as disappointing, and we are going to use SIAC for Stage I tumours only. Resection of the tumour continues to provide the only chance of a permanent cure with these patients.  相似文献   

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A total of 365 isolates of Borrelia burgdorferi sensu lato from 12 major administrative territories of Russia (from St. Petersburg in the west to South Sakhalin in the east) and from the Czech Republic, Estonia, Lithuania, Byelorussia, Moldavia, Ukraine and Kirghizia were identified by analysis of restriction polymorphism of ribosomal rrf-rrl spacer amplicons. The isolates were obtained mainly from ixodes persulcatus and I. ricinus ticks. Other sources included small mammals, human patients and I. trianguliceps ticks. The results showed that B. garinii (two variants) together with B. afzelii circulated throughout the territories studied. The distribution of the variant NT29 of the species B. garinii, the most frequently isolated, was associated with that of I. persulcatus ticks. B. burgdorferi sensu stricto, and the species B. valaisiana and B. lusitaniae (formerly the genomospecies VS116 and PotiB2, respectively) were isolated only from I. ricinus ticks in the western part of the studied territories. None of these three species were found in 327 isolates from Russia where I. persulcatus is the most frequently distributed vector. This work also provides evidence for a high incidence of mixed Borrelia infections within vectors and hosts (9.3% of isolates were mixtures of Borrelia species). A detailed analysis of Borrelia species distribution over the territories studied is presented.  相似文献   

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OBJECTIVE: To determine rates of suicide associated with pregnancy by the type of pregnancy. DESIGN: Register linkage study. Information on suicides in women of reproductive age was linked with the Finnish birth, abortion, and hospital discharge registers to find out how many women who committed suicide had had a completed pregnancy during her last year of life. SETTING: Nationwide data from Finland. SUBJECTS: Women who committed suicide in 1987-94. RESULTS: There were 73 suicides associated with pregnancy, representing 5.4% of all suicides in women in this age group. The mean annual suicide rate was 11.3 per 100,000. The suicide rate associated with birth was significantly lower (5.9) and the rates associated with miscarriage (18.1) and induced abortion (34.7) were significantly higher than in the population. The risk associated with birth was higher among teenagers and that associated with abortion was increased in all age groups. Women who had committed a suicide tended to come from lower social classes and were more likely to be unmarried than other women who had had a completed pregnancy. CONCLUSIONS: The increased risk of suicide after an induced abortion indicates either common risk factors for both or harmful effects of induced abortion on mental health.  相似文献   

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Only a few reports of adenomatoid odontogenic tumour (AOT) in Africans have been published. Clinical, histological and radiographic features as well as treatment results of thirteen new cases of AOT seen at the University College Hospital, Ibadan were reviewed. This lesion constituted 12.1% of odontogenic tumours. This study shows a male: female ratio of 1.2:1. This contrasts with the reported male: female ratio of 1:3 in the United States, Britain, Sri Lanka and Japan. The higher male incidence may be peculiar to Nigeria. Although the peak incidence was in the second decade of life, four patients were over 20 years of age. The mean age was 23.2 years for all patients. None of the patients presented with recurrence on follow up.  相似文献   

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The purpose of this paper was to describe the transition of sterilization in Finland from an eugenic tool to a contraceptive. Historical data were drawn from earlier reports in Finnish. Numbers of and reasons for sterilizations since 1950 were collected from nationwide sterilization statistics. Prevalence, characteristics of sterilized women, and women's satisfaction with sterilizations were studied from a 1994 nationwide survey (74% response rate). Logistic regression was used for adjustments. In the first half of the 20th century, eugenic ideology had influence in Finland as in other parts of Europe, and the 1935 and 1950 sterilization laws had an eugenic spirit. Regardless of this, the numbers of eugenic sterilizations remained low, and in practice, family planning was the main reason for sterilization. Nonetheless, prior to 1970 not all sterilizations were freely chosen, because sterilizations were sometimes used as a precondition for abortion. Female sterilizations showed remarkable fluctuation over time. Male sterilizations have been rare. The reasons stipulated by the law did not explain the numbers of sterilizations. In a 1994 survey, 9% of Finnish women reported they were using sterilization as their current contraceptive method (n = 189). Compared to women using other contraceptive methods, sterilized women were older, had had more births and pregnancies, and came from lower social classes. Sterilized women were satisfied with their sterilization, but there were women (8.5%) who regretted it. In conclusion, sterilizations have been and are likely to continue to be an important family planning method in Finland. The extreme gender ratio suggests a need for promoting male sterilizations, and women's expressed regrets suggest consideration of a higher age limit.  相似文献   

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Paraffin-embedded specimens from 21 patients (mean age 49 years) with malignant melanocytic tumors of the central nervous system were studied. Extraneuronal primary tumors were situated at the trunk (38%), the lower (14%) or upper extremity (10%), and the head/neck region (5%). In 33% no extraneural primary tumor could be detected. The tumor location was frontal (19%), occipital (19%), parietal, spinal, multifocally (14%, respectively), or temporal (5%). Four subtypes were distinguished according to the predominant histological cell type: pleomorphic, epithelioid, spindle- and mixed-cell tumors. 29% contained no melanin, most of them belonging to the epithelioid subtype. The morphology and immunohistochemical reactivity for different antibodies (KL-1, EMA, VIM, HMB-45, NKI-C3, S-100, and MIB-1/Ki-67) were assessed. Positive staining was demonstrated for HMB-45 (in 86% of cases), NKI-C3 (100%), S-100 (95%), vimentin (75%), and KL-1 (33%). No expression of the cytokeratin EMA could be detected. The mean proliferation index measured by MIB-1 immunoreactivity was 21%. The 4 histological subtypes were found to express different antigen patterns. In the analysis of CNS tumors of unknown origin, the panel of antibodies used for diagnosis should include HMB-45 as the most specific marker for malignant melanoma.  相似文献   

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RATIONALE AND OBJECTIVES: Tumor volume is an important parameter for clinical decision making. At present, semiautomatic image segmentation is not a standard for tumor volumetry. The aim of this work was to investigate the usability of semiautomatic algorithms for tumor volume determination. METHODS: Semiautomatic region- and volume-growing, isocontour, snakes, hierarchical, and histogram-based segmentation algorithms were tested for accuracy, contour variability, and time performance. The test were performed on a newly developed organic phantom for the simulation of a human liver and liver metastases. The real tumor volumes were measured by water displacement. These measured volumes were used as the gold standard for determining the accuracy of the algorithms. RESULTS: Variability of the segmented volumes ranging from 3.9 +/- 3.2% (isocontour algorithm) to 11.5 +/- 13.9% (hierarchical segmentation) was observed. The segmentation time per slice varied between 32 (volume-growing) and 72 seconds (snakes) on an IBM/RS6000 workstation. CONCLUSIONS: Only the region-growing and isocontour algorithms have the potential to be used for tumor volumetry. However, further improvements of these algorithms are necessary before they can be placed into clinical use.  相似文献   

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Though the exact and cumulative incidence of osteoporosis has not been examined, using the criteria that osteoporosis is defined by a decrease of bone mineral density (BMD) below 70% from young adult mean (YAM), the prevalence of osteoporosis among the Japanese women can be estimated as to be more than either 30% (by spinal BMD) or 37% (by femoral BMD) in 60's, 37% or 64% in 70's, and 42% or 90% in 80's, respectively. The total number of osteoporosis among the women with age 50 and over can be also estimated as to be either about 5 million (by spinal BMD) or 8.5 million (by forearm BMD). National survey shows that the ratio of people receiving treatment for osteoporosis is 34.5 per 1,000 among the elderly with age 65 and over. In addition, both functional transition and survival rate of discharged patients with osteoporotic hip fracture are discussed as prognosis of osteoporosis.  相似文献   

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