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161.
The aim of the present study was to examine the involvement of brain structures, especially the amygdala-hippocampal complex, in dementia of Alzheimer type (DAT), and to assess the relation of amygdala-hippocampal atrophy with memory dysfunction. 14 patients with DAT and 10 healthy age-matched controls were examined with different neuropsychologic tests including the UCLA-Auditory Verbal Learning Test. MRI was performed with a conventional 1.5-tesla scanner. Atrophy was found in many brain structures of demented subjects in comparison with healthy age-matched controls. The volumes of amygdala-hippocampal complexes and of the temporal lobes of demented subjects were more reduced than the total brain volume and other structures. Memory dysfunction was highly correlated with atrophy of the amygdala-hippocampal complexes and of the temporal lobes. Consequently, DAT seems to affect the amygdala-hippocampal complex and their related function (i.e. memory) more than other cerebral structures, but cerebral degeneration in DAT is not restricted to these structures.  相似文献   
162.
About 15 of all women in the reproductive age are involved by recurrent abortions. The pathophysiology is different; chromosomal, infectious, immunologic and endocrine reasons and anomalities of the uterine cave are discussed. Though there is a discrepancy between the regular secretory phase needed for implantation and low progestins in early pregnancy inducing abortion, the theory of recurrent abortions induced by ovarian malfunction is critically discussed in literature. Basing on the knowledge of the regulation of ovarian function and a delayed pregnancy without ovarian function in early pregnancy in a patient with recurrent abortions, a defect of the corpus luteum-rescue is the most probable explanation. This defect characterized by regular beta-HCG- and pathological decreased progestin and estradiol levels should be treated by substitution of progestin and estradiol. Though a defect of the HCG-receptor is possible a HCG-substitution seems to be an inadequate therapy.  相似文献   
163.
164.
Two broad-host-range vectors previously constructed for use in soil bacteria (A. G. Matthysse, S. Stretton, C. Dandie, N. C. McClure, and A. E. Goodman, FEMS Microbiol. Lett. 145:87-94, 1996) were assessed by epifluorescence microscopy for use in tagging three marine bacterial species. Expression of gfp could be visualized in Vibrio sp. strain S141 cells at uniform levels of intensity from either the lac or the npt-2 promoter, whereas expression of gfp could be visualized in Psychrobacter sp. strain SW5H cells at various levels of intensity only from the npt-2 promoter. Green fluorescent protein (GFP) fluorescence was not detected in the third species, Pseudoalteromonas sp. strain S91, when the gfp gene was expressed from either promoter. A new mini-Tn10-kan-gfp transposon was constructed to investigate further the possibilities of fluorescence tagging of marine bacteria. Insertion of mini-Tn10-kan-gfp generated random stable mutants at high frequencies with all three marine species. With this transposon, strongly and weakly expressed S91 promoters were isolated. Visualization of GFP by epifluorescence microscopy was markedly reduced when S91 (mini-Tn10-kan-gfp) cells were grown in rich medium compared to that when cells were grown in minimal medium. Mini-Tn10-kan-gfp was used to create an S91 chitinase-negative, GFP-positive mutant. Expression of the chi-gfp fusion was induced in cells exposed to N'-acetylglucosamine or attached to chitin particles. By laser scanning confocal microscopy, biofilms consisting of microcolonies of chi-negative, GFP+ S91 cells were found to be localized several microns from a natural chitin substratum. Tagging bacterial strains with GFP enables visualization of, as well as monitoring of gene expression in, living single cells in situ and in real time.  相似文献   
165.
Overexpression of the erbB-2 tyrosine kinase receptor, p185erbB-2, is a common alteration in non-small cell lung cancer (NSCLC) and has been associated with poor prognosis and a tumor drug resistance phenotype. In this study, we have examined the consequences of erbB-2 depletion on DNA repair, cell cycle, and apoptosis using a panel of NSCLC cell lines constitutively overexpressing erbB-2 receptor. Depletion of the erbB-2 was achieved using the tyrosine kinase inhibitor CP127,374 which promotes erbB-2 degradation. Treatment with CP127,374 concentrations which deplete erbB-2 and inhibit tyrosine phosphorylation resulted in downregulation of DNA repair mechanisms and cell accumulation at G1 phase of the cell cycle. GI arrest was observed in cells with mutated p53 as well as cells lacking p53 protein, suggesting a p53-independent mechanisms. NSCLC cells which overexpress erbB-2 were more resistant to cisplatin-induced cytotoxicity in comparison to cells expressing low levels of erbB-2. Treatment with CP127,374 alone did not result in any induction of apoptosis. A combination of CP127,374 and cisplatin, however, was more potent in cell growth inhibition and induction of apoptosis compared to treatment with cisplatin alone. Together, our results further support a pivotal role of erbB-2 signaling in the regulatory balance between DNA repair, cell cycle checkpoints and apoptosis; all these mechanisms are essential determinants for tumor cell destiny following chemotherapy stress.  相似文献   
166.
The aim of our study was to validate a hip fracture risk function, composed of age and femoral neck bone mineral density (BMD). This estimate of the 1-year cumulative risk was previously developed on the basis of Dutch hip fracture incidence data and BMD in men and women. A cohort of 7046 persons (2778 men) aged 55 years and over was followed for an average of 3.8 years. The 1-year hip fracture risk estimate was calculated for each participant according to the risk function and categorized as low (<0.1%), moderate (0.1 to < 1%), or high (> or =1%). Observed first hip fracture incidence was then analyzed for each of these risk categories by age and gender. Additionally, we calculated the relative risk per standard deviation (SD) decrease in femoral neck BMD in this population. At baseline, 2360 individuals were categorized as low risk, 2567 as moderate risk, and 378 as high risk During follow-up, 110 first hip fractures were observed corresponding to an incidence rate of 4.1/1000 person-years (pyrs) (95% confidence interval 3.4-5.0). The observed incidence rate in the low risk group was 0.2/1000 pyrs (0.1-0.9), 2.7/1000 pyrs (1.8-3.9) in the moderate risk group, and 18.4/1000 pyrs (12.4-27.2) in the high risk group. Below the age of 70 years, incidence was low in all categories, and very few individuals were considered at high risk Above the age of 70 years, the observed incidence was high in the high risk group, while in the low and moderate risk groups, the incidence remained low even over 80 years of age. In women, the age-adjusted relative risk for hip fractures was 2.5 per SD decrease in femoral neck BMD (1.8-3.6), while in men this relative risk was 3.0 per SD (1.7-5.4). In conclusion, we observed a similar relation of hip fracture with femoral neck BMD in men and women and were able to predict accurately hip fracture rates over a period of almost 4 years.  相似文献   
167.
Visualization tools for bioinformatics ideally should provide universal access to the most current data in an interactive and intuitive graphical user interface. Since the introduction of Java, a language designed for distributed programming over the Web, the technology now exists to build a genomic data visualization tool that meets these requirements. Using Java we have developed a prototype genome browser applet (BioViews) that incorporates a three-level graphical view of genomic data: a physical map, an annotated sequence map, and a DNA sequence display. Annotated biological features are displayed on the physical and sequence-based maps, and the different views are interconnected. The applet is linked to several databases and can retrieve features and display hyperlinked textual data on selected features. In addition to browsing genomic data, different types of analyses can be performed interactively and the results of these analyses visualized alongside prior annotations. Our genome browser is built on top of extensible, reusable graphic components specifically designed for bioinformatics. Other groups can (and do) reuse this work in various ways. Genome centers can reuse large parts of the genome browser with minor modifications, bioinformatics groups working on sequence analysis can reuse components to build front ends for analysis programs, and biology laboratories can reuse components to publish results as dynamic Web documents.  相似文献   
168.
Eight cases of hydatid disease of the abdomen and thorax were diagnosed by fine-needle aspiration (FNA) cytology under ultrasound guidance. The age of the patients ranged from 28 to 60 yr with a median of 34.5 yr; the male to female ratio was 2:6. None of the cases were diagnosed clinically as hydatid diseases but following ultrasonography suspicion of hydatid cyst was raised in two cases. The locations of cysts were the liver in six cases, the lung in one case, and the mediastinum in one case. FNA yielded clear fluid in five cases and turbid fluid in three cases. Laminated cyst wall, scolices, and hooklets were observed in one case, scolices and hooklets were present in two cases, and laminated cyst wall along with hooklets were seen in two cases. The remaining three cases showed only laminated cyst walls which yielded positive reaction with periodic acid-Schiff reaction. Inflammatory cell reaction in the form of neutrophils was observed in four cases, including the three cases where turbid fluid was aspirated. Epithelioid cell reaction was present in one case. None of our eight cases showed any untoward allergic reaction following FNA.  相似文献   
169.
PURPOSE: A review was undertaken of 119 children seen at the Children's Hospital of Philadelphia between 1972 and 1992 to assess the impact of adjuvant therapies for patients with low-stage neuroblastoma (NBL). PATIENTS AND METHODS: Twenty-one of 119 International Neuroblastoma Staging System (INSS) stage 1, 2a, 2b, and 4s patients seen received initial adjuvant treatment postoperatively and 98 did not. The patients were further subdivided according to decade, age, presence of residual disease, and lymph node status. Outcomes were then compared. RESULTS: The event-free survival (EFS) rate for those who received adjuvant therapy was 52% versus 86% for those who did not. The 5-year survival rate was 68% and 94%, respectively. Age (< or > 12 months), extent of residual disease, and status of lymph nodes did not influence survival. Over the two decades, the reasons for selecting treatment changed as new and powerful additional prognostic factors were identified; 71% of patients received no adjuvant treatment in the first decade, compared with 90% in the second. EFS rates for untreated patients by decade were 79% and 89%, and 5-year survival rates were 85% and 98%, respectively. CONCLUSION: It is possible to define most low-stage NBL as favorable-even in patients with positive lymph nodes and gross residual disease-and to omit initial adjuvant treatments successfully.  相似文献   
170.
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