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91.
MG Maher E Sapi B Turner A Gumbs PL Perrotta D Carter BM Kacinski BG Haffty 《Canadian Metallurgical Quarterly》1998,4(8):1851-1856
The macrophage colony-stimulating factor receptor (CSF-1R), the product of the c-fms proto-oncogene, regulates normal proliferation and differentiation of macrophages and trophoblasts. Recent research found abnormal expression of CSF-1R in human carcinomas of the breast, endometrium, and ovary. Furthermore, activation of CSF-1R by its ligand has been shown to regulate invasiveness and anchorage-independent growth in breast carcinoma cells. To study the significance of CSF-1R expression in breast cancer, we designed a case-controlled immunohistochemical study. We chose 80 patients from a database of 1200 early stage I or II breast cancer patients treated with conservative surgery and radiation therapy. Expression of CSF-1R in the tumors of 40 patients who experienced an ipsilateral breast tumor recurrence (IBTR) as a primary site of relapse were compared with 40 patients who had not experienced an IBTR. The index and control patients were matched by age, clinical stage, nodal status, and follow-up. Paraffin-embedded sections were immunostained with antibodies directed toward CSF-1R. For the CSF-1R antibody, a total of 28 index cases (70%) demonstrated strong staining, whereas only 16 control cases (40%) demonstrated high immunoreactivity (P = 0.007). The CSF-1R antibody showed a positive correlation for local relapse, but no correlation was found between CSF-1R expression and distant metastasis. In summary, our findings provide evidence for the poor prognostic role of CSF-1R in IBTR. 相似文献
92.
J Weinzweig PL Schnur JP McConnell JB Harris PM Petty TP Moyer D Nixon 《Canadian Metallurgical Quarterly》1998,101(7):1836-1841
The silicone breast implant controversy rages on. Recent work has demonstrated that normal or baseline breast tissue silicon levels in women who had had no prior exposure to any type of breast implant may be as high as 446 microg/gm of tissue. These data ranged from 4 to 446 microg/gm of tissue, with a median of 27.0 microg/gm of tissue. In addition, numerous other epidemiologic and rheumatologic studies have demonstrated no association between silicone breast implants and any connective-tissue diseases. Despite these reports, the use of silicone implants remains restricted. The present study measured breast and capsular tissue silicon levels from 23 breasts in 14 patients with saline implants, and from 42 breasts in 29 patients with silicone implants. No patient in the saline implant group presented with signs or symptoms of connective-tissue disease. Patients with silicone implants, however, were divided into three groups based on the presence or absence of signs or symptoms of connective-tissue disease: group I, no symptoms or signs; group II, + symptoms, no signs; and group III, + symptoms, + signs. Six patients in group III were diagnosed with a specific connective-tissue disease, including systemic lupus erythematosus, rheumatoid arthritis, or scleroderma. The most common indications for implant removal or exchange were capsular contracture and implant rupture, although 41 percent of patients with silicone implants expressed media-related concern over the implant issue. The most common symptoms described by patients in groups II and III were joint pain and stiffness, arm pain and numbness, and fatigue. In all groups, capsular tissue silicon levels were significantly greater than breast tissue levels. This finding may indicate that the capsule serves as a barrier to the distribution of silicone from the implant into adjacent breast tissue. Although breast tissue silicon levels in patients with silicone implants were not significantly greater than those in patients with saline implants (p = 0.48), capsular tissue levels in patients with silicone implants were, indeed, significantly greater than those in patients with saline implants (p < 0.001). However, no statistically significant differences in tissue silicon levels were observed with relation to the presence or absence of connective-tissue disease signs or symptoms in patients with silicone implants (groups I to III). Therefore, these data strengthen the conclusion that there is no association between tissue silicon levels and connective-tissue disease. 相似文献
93.
94.
JM Cho AJ LaPorta JR Clark MJ Schofield SL Hammond PL Mallory 《Canadian Metallurgical Quarterly》1994,8(12):1380-3; discussion 1383-4
The clinical observation that a laparoscopic cholecystectomy is a minimally invasive operation has not been demonstrated on a biochemical basis. Interleukin-6, a known endogenous pyrogen and hepatocyte-stimulating protein, correlates with the significance of surgical trauma. Utilizing the IL-6 immunoassay, we studied this biochemical parameter of trauma to compare its response in laparoscopic vs open cholecystectomy. Sixteen patients who underwent only laparoscopic cholecystectomy showed peak IL-6 concentrations of 51 pg/ml (22-86) vs a peak IL-6 concentration of 124 pg/ml (56-225) for open cholecystectomy. Six additional patients who underwent an ERCP followed by laparoscopic cholecystectomy showed a dramatic rise in peak IL-6 concentration to 315 pg/ml (15-634). These results biochemically confirm the true minimal invasiveness of laparoscopic cholecystectomy. The findings in the ERCP-followed-by-laparoscopic-cholecystectomy group support the theory that two invasive procedures in close proximity may prime the cytokine system in its response to surgical trauma. 相似文献
95.
96.
There are known 3 likely mechanisms of virus conveyance into the central nervous system (CNS). These include hematogenic penetration, spread along the peripheral nerves, and the olfactory pathway which begins from the infected olfactory neuroepithelial cells. The possibility of viral spread into CNS via the olfactory pathway was shown for the representatives of togaviruses, herpesviruses, coronaviruses, rhabdoviruses, and for some others. This study suggests that the olfactory pathway of viral conveyance into CNS may be blocked by specific mucosal antibodies in the nasal mucosa. The recombinant TK- variant of WR vaccinia strain with inserted genes coding structural and nonstructural proteins of TBE virus is accumulated in the branches of the respiratory tract only while the parenteral vaccinia strain is detected in the brain regions, spleen, respiratory tract, and in blood. The protective activity of recombinant strain and inactivated TBE vaccine after mice immunization by escarification or intranasally, or subcutaneously was comparatively studied. The findings indicate that intranasal immunization by recombinant strain is the most protective against intraperitoneal challenge by TBE virus. The mucosal and humoral immune response that was induced by intranasal immunization seems to provide the highest levels of protection, which was experimentally observed. 相似文献
97.
98.
PL Grimaldi 《Canadian Metallurgical Quarterly》1998,29(11):10-12
Prospective payment systems are replacing the methods Medicare uses to reimburse home health agencies, skilled nursing facilities, and rehabilitation hospitals, as well as imposing new limits on payments for outpatient rehabilitation services. Medicare stands to save substantial sums of money and possibly to hasten the formation of integrated delivery systems for postacute care. 相似文献
99.
PL Ivanov 《Canadian Metallurgical Quarterly》1998,41(4):30-47
The paper presents the results of international complex molecular genetic expert identification of skeletal remains of 9 subjects buried near the Koptiaki road in Ekaterinburg region, presumably belonging to the Romanov Royal Family and persons in their attendance. The armory of methods based on analysis of the least permissible amounts of DNA by the polymerase chain reaction and direct fluorescent sequencing of amplified DNA fragments included the latest scientific technologies. In addition, new methods were developed and used, which have no analogs in the world expert practice. The strategy included identification of biological gender of skeletons, of familial group among exhumed individuals, and of ties of relationship of this family with two independent maternal branches of the Romanov genealogical tree using tracing kindred markers based on mitochondrial DNA (mtDNA). The study was carried out in two stages: in 1992-1993 at Aldermaston Criminology Center of Home Office of the UK with participation of British specialists and in 1995 at Military Medical Institute of Ministry of Defence of the USA in Washington with participation of American specialists. In 1993 five skeletons were identified as Emperor Nicholas II, Empress Alexandra Fedorovna, and their three daughters with 99.6% certainty. From modern criminological viewpoint, the result could not be considered as sufficiently certain for such an extraordinary case, and therefore in 1995 molecular genetic studies of presumable remains of Nicholas II and his brother Prince Georgi? Romanov were carried out again. The results showed absolute positional identity of mtDNA genetic code of these two men due to an extremely rare genetic abnormality (heteroplasmia), and thus the problem of appurtenance of the remains to the Romanov royal family was solved. 相似文献
100.