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2.
In the differential clinical diagnosis of mammary neoplasms, adenocarcinoma can safely be excluded only after biopsy and microscopic study.In a series of 177 cases of mammary cancer treated by surgery with x-ray therapy, 30.4 per cent of the patients are alive three years or more after treatment; 18 per cent five years or longer.Only one of every four patients presents herself with a lesion still within the breast. Exclusive of Group I this results in a cure in 86.1 per cent in Group II and 15.4 per cent in Group III. The mortality rate then increases five and one-half times as spread occurs beyond the breast.The results of irradiation therapy for curative purposes in recurrent or metastatic mammary adenocarcinoma are poor.
Percentage of cure by stages.
  相似文献   
3.
OBJECTIVE: The aim of this study was to assess changes in early and late haemodynamic status after the Norwood procedure (NP), caused by the implementation of right ventricle-to-pulmonary artery shunt (RV-PA). METHODS: A consecutive series of 68 children with hypoplastic left heart syndrome underwent NP: Group 1 (n=31) with the application of a modified Blalock-Taussig shunt and Group 2 (n=37) with RV-PA. Haemodynamic data from the early postoperative period (72 h after the operation) and cardiac catheterisation data, as well as blood tests before the hemi-Fontan procedure (HF) were analysed. Univariate (chi(2) test, Mann-Whitney's and Student's t-tests) and multiple regression analysis were carried out. RESULTS: In Group 1, circulatory collapse requiring resuscitation occurred in 15 (48.4%) children, within 72 h after the procedure. The resuscitation was unsuccessful in nine (29%) cases. The operative mortality (30 days) was 35%. In Group 2, two (5%) children died within the early and two (5%) within the late postoperative period. The postoperative course in the remaining children from Group 2 was uneventful. In Group 2 there was a significantly higher mean diastolic pressure after NP (P<0.05). The arterial pulse pressure after NP was significantly lower in Group 2 (P<0.05). Before HF, the application of RV-PA was associated with a lower Qp:Qs ratio (P=0.020), lower aortic pulse pressure (P=0.004) and lower aortic oxygen saturation (P=0.039). CONCLUSIONS: A stable haemodynamic status due to independent coronary perfusion, higher diastolic and lower pulse pressure is the most advantageous effect of RV-PA, resulting in a lower mortality and morbidity after NP. A lower Qp:Qs ratio eliminates the danger of the ventricular volume overload and ensures good conditions for the development of the pulmonary circulation before HF.  相似文献   
4.
Early results (12 weeks after surgery) of the lumbar spinal stenosis operative treatment were assessed in the group of 36 patients (aged 40-65 years). In 72% of patients posterior fusion was applied. In the results evaluation lumbar pain, low extremities pain, neurogenic claudicat ion, sensory disturbances and functional status were taken in account. A significant decrease in low extremities and lumbar pain was observed. Some sensory disturbances after operative treatment did not affect general high patients assessment of the performed surgical procedures (positive 80.5% cases).  相似文献   
5.
Migration, proliferation and invasive growth of myofibroblasts are key cellular events during formation of granulation tissue in situations of wound healing, arteriosclerosis and tumor growth. To study the invasive phenotype of myofibroblasts, we established an assay where arterial tissue from chicken embryos was embedded in fibrin gels and stimulated with growth factors. Addition of serum, PDGF-BB and FGF-2, but not VEGF-A, resulted in an outgrowth of cellular sprouts with a pattern that was similar to the organization of cells invading a provisional matrix in an in vivo model of wound healing using the chicken chorioallantoic membrane. Sprouting cells were defined as myofibroblasts based on being alpha-smooth muscle actin-positive but desmin-negative. There was no contribution of endothelial cells in outgrowing sprouts. The acquired myofibroblastic phenotype was stable since sprout-derived cells resumed sprouting in a growth factor-independent manner when re-embedded as spheroids in a fibrin matrix. Invasive growth and sprouting of vascular smooth muscle cells was not limited to chicken cells since a similar response was seen when spheroids composed of purified primary human aortic smooth muscle cells were embedded in fibrin. Finally, a technique for flat visualization of the three-dimensional sprouting and a quantification method is described. This ex vivo model allows quantitative analysis of invasive growth and differentiation of vascular smooth muscle cells and fibroblasts into myofibroblasts.  相似文献   
6.
Carbon dioxide and propylene oxide (PO) were copolymerized using diethylzinc in addition with benzenedi- and triols, aliphatic diols and triols, and aminophenols as catalyst systems. A large amount of CO2/PO alternating copolymer, {poly(propylene carbonate), poly(oxycarbonyloxypropylene), of high molecular weight was obtained using the homogeneous (C2H5)2Zn/pyrogallol (2:1 by mole) system ( 1 ). The (C2H5)2Zn/o-aminophenol system ( 2 ) (also homogeneous) appeared to be much less active in the copolymerization of CO2 with PO than the former one. From the other studied systems, that appeared to be heterogeneous, (C2H5)2Zn/resorcinol (1:1 by mole) was the most active one, but less active than the system 1 . Further, the copolymerization of CO2 and PO was studied in the presence of the (C2H5)2Zn/resorcinol (1:1 by mole) system at various temperatures and in reaction media of different basicity. On the basis of the obtained results of the copolymerization of CO2 with PO and of measurements of the quantity of ethane evolved in the reactions between the catalytic systems' components, structures of several catalysts, particularly homogeneous ones, are suggested and some aspects of the copolymerization mechanism are discussed.  相似文献   
7.
We have studied the influence of a temperature-sensitive cdc2-1 mutation in DNA polymerase on the selection-induced mutation occurring at the LYS-2 locus in the yeast Saccharomyces cerevisiae. It was found that in cells plated on synthetic complete medium lacking only lysine, the numbers of Lys+ revertant colonies accumulated in a time-dependent manner in the absence of any detectable increase in cell number. When cdc2-1 mutant cells, after selective plating, were incubated at the restrictive temperature of 37°C for 5 h daily for 7 days, the frequency of an adaptive reversion of lys - Lys+ was significantly higher than the frequency in cells incubated only at the permissive temperature, or in wild-type cells incubated either at 23°C or 37°C. Therefore, when the proof-reading activity of DNA polymerase is impaired under restrictive conditions, the frequency of adaptive mutations is markedly enhanced.  相似文献   
8.
Natural mechanisms protecting against cancer   总被引:10,自引:0,他引:10  
Carcinogenesis is a multistage process. At each step of this process, there are natural mechanisms protecting against development of cancer. The majority of cancers in humans is induced by carcinogenic factors present in our environment including our food. However, some natural substances present in our diet or synthesized in our cells are able to block, trap or decompose reactive oxygen species (ROS) participating in carcinogenesis. Carcinogens can also be removed from our cells. If DNA damage occurs, it is repaired in most of the cases. Unrepaired DNA alterations can be fixed as mutations in proliferating cells only and mutations of very few strategic genes can induce tumor formation, the most relevant are those activating proto-oncogenes and inactivating tumor suppressor genes. A series of mutations and/or epigenetic changes is required to drive transformation of a normal cell into malignant tumor. The apparently unrestricted growth has to be accompanied by a mechanism preserving telomeres which otherwise shorten with succeeding cell divisions leading to growth arrest. Tumor can not develop beyond the size of 1–2 mm in diameter without the induction of angiogenesis which is regulated by natural inhibitors. To invade the surrounding tissues epithelial tumor cells have to lose some adhesion molecules keeping them attached to each other and to produce enzymes able to dissolve the elements of the basement membrane. On the other hand, acquisition of other adhesion molecules enables interaction of circulating tumor cells with endothelial cells facilitating extravasation and metastasis. One of the last barriers protecting against cancer is the activity of the immune system. Both innate and adaptive immunity participates in anti-tumor effects including the activity of natural killer (NK) cells, natural killer T cells, macrophages, neutrophils and eosinophils, complement, various cytokines, specific antibodies, and specific T cytotoxic cells. Upon activation neutrophils and macrophages are able to kill tumor cells but they can also release ROS, angiogenic and immunosuppressive substances. Many cytokines belonging to different families display anti-tumor activity but their role in natural anti-tumor defense remains largely to be established.  相似文献   
9.
Allergic angiitis and granulomatosis (Churg-Strauss syndrome) is one of the rare form of idiopathic (primary) vasculitis. It is characterized by asthma, blood hypereosinophilia and typical microscopic features: nectrotizing vasculitis, tissue infiltration by eosinophils and extravasal granulomas. We present an autopsy case of 55-years old man with Churg-Strauss syndrome complicated by eosinophilic myocarditis.  相似文献   
10.
Investigations on the reactions of diethylzinc ( 1 ) with resorcinol ( 2 ) and phloroglucinol ( 8 ) were carried out for different mole ratios of the reactants. It was found that the reaction of 1 with 2 at a mole ratio of 1:1 is a two step process. In the first step 1 reacts very rapidly with half of applied 2 yielding di(ethylzinc) resorcinolate ( 6 ), which then reacts slowly with the remaining amount of 2 . It was found that zinc 3-ethylzincoxyphenolate resorcinolate ( 5 ) formed in the second step is an active catalyst of the copolymerization reaction of carbon dioxide with propylene oxide. The reaction of 1 with 8 shows a similar course.  相似文献   
StagePatients TreatedPer Cent Cures
I1100.0
II and IIa4086.1
III and IIIa13015.4
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