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1.
Objective The degree of Left Ventricular Mass Index (LVMI) regression following aortic valve replacement correlates with long-term survival. This study aims to assess the extent of LVMI regression at 3 months following aortic valve replacement (AVR) with different types and sizes of mechanical valves in rheumatic aortic valve disease. Methods The LVMI regression was studied in 34 consecutive patients, undergoing elective AVR for rheumatic aortic stenosis and/or regurgitation. They were grouped in A and B, matched in age, body surface area and pre-operative LVMI, receiving respectively a tilting disc and a bileaflet mechanical valve. The LVMI was calculated by M-mode echocardiography using the Devereux' formula pre-operatively and three months post-operatively. The trend of LVMI reduction was compared between the two groups and amongst the patients with stenotic, regurgitant and mixed aortic valve, pathologies; and receiving different sizes of valves. Results The mean preoperative LVMI was 199g±79.5 g/m2. At three months post aortic valve replacement, the mean LVMI was 130g±49.0 g/m2. There was a significant reduction of LVMI post-operatively (p=0.001) at three months follow-up. The extent of LVMI regression following surgery amongst the groups A and B did not vary significantly (p=0.92). The extent of LVMI regression did not vary significantly in patients with different aortic valve pathology nor with different sizes of the valves implanted. Conclusions There is a significant early LVMI regression following aortic valve replacement in rheumatic aortic valve disease. The type and the size of the mechanical prosthesis or the rheumatic pathology do not appear to influence this regression.  相似文献   
2.
Between November 1988 and February 1992, 416 patients required coronary endarterectomy for diffuse coronary artery disease. This constitutes 16.19 per cent of all patients who underwent coronary artery bypass grafting during the same period. A total of 528 endarterectomies were performed. Four-hundred and twenty-two endarterectomies were performed on right coronary system and 106 endarterectomies were performed on left coronary system. One-hundred and twelve (26.92%) patients required more than one endarterectomies. The hospital mortality was 2.16 percent. 3.37 per cent of patients had perioperative infarction. Intraaortic balloon pump was required in 1.92 per cent of patients. 5.77 per cent of the patients had significant arrhythmias. The patients have been followed up for a mean period of 27 months. One-hundred and forty patients were evaluated by exercise multigated radionuclide angiogram. One-hundred and thirty-four (95.71%) patients showed increase in ejection fraction as compared to preoperative value. Six (4.29%) patients did not show any significant change while eight (5.71%) patients had fall in ejection fraction. Postoperative coronary angiogram was done in 44 patients at a mean of 10 months. 89.59 per cent of grafts to the endarterectomised vessels and 91.67% of grafts to nonendarterectomised vessel were patent. The difference between the two groups was not statistically significant.  相似文献   
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Serum copper and iron in ischemic heart disease   总被引:1,自引:0,他引:1  
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6.
Summary The patterns of expression of the human-tumor-associated antigens, CO17-1A, GA73-3, BR55-2, GICA19-9, CA50 and carcino-embryonic antigen (CEA) were studied in the normal colonic mucosa (the last three also in the serum) of Sprague-Dawley rats. Four immunohistochemically different segments were identified: caecum, ascending colon, transverse colon and descending colon. The immunohistochemical reactions of the cells at the lower part of the crypt were essential for the distinction of the four segments. In the caecum, the MAbs 17-1A, 73-3 and 19-9 stained the glycocalyx of the cells of the lower part of the crypts and the Golgi apparatus of the intercalated cells (IC). MAb55-2 stained very weakly the goblet-like cells (GLC) of the lower part of the crypt of transverse colon, in addition to a nearly complete lack of reaction in the upper part of the crypts. In the ascending colon, the lower part of the crypts showed a characteristic diffuse staining of the intercalated cells with MAb55-2. The perinuclear and mucosal staining observed in the GLC of the transverse colon with MAbs 17-1A, 73-3 and 19-9 as against the supranuclear and Golgi zone staining observed in the GLC/goblet cells (GC)/columnar cells (CC) of the lower part of crypts of the descending colon with the same MAbs, distinguished the former segment from the latter. The IC demonstrated by immunohistochemistry in the lower parts of the crypts of caecum and ascending colon appear to correspond to the replicating cells of the colonic crypts.  相似文献   
7.
Hematological profile of HIV positive patients   总被引:4,自引:0,他引:4  
A series of 500 HIV positive patients referred to our centre for CD4 and CD8 cell enumeration are included in this study. The following parameters were studied in each of these patients: Hb, RBC indicates, WBC count, platelet count, three part differential count, absolute CD4 and CD8 counts. Male:Female ratio of 4.9:1 was noted 30.8% patients has anemia (Hb<10 gm%), with an average Hb value of 8.1 gm%. The anemia was normochromic, normocytic in 61% of patients, microcytic in 33% and macrocytic in 6% patients. The absolute CD4 count was less than 200 ul in 50.2% patients with an average value of 92/ul. Thrombocytopenia was seen in 13% patients with average platelet count 0.92x10(3)/ul.  相似文献   
8.
Radiotherapy (or radiation therapy) uses ionizing radiation to selectively kill cancer cells, especially for solid tumours. Like surgery, it is meant to be a ‘local’ treatment, although its beneficial systemic effects are being discovered. It is most commonly used in addition to surgery (adjuvant, e.g. breast), but its role in the neoadjuvant setting in combination with chemotherapy for some cancers (e.g. rectum) is also established. In early stages of cancer, it can be the definitive treatment, avoiding surgery and enabling organ preservation (e.g. larynx), while in late stages, it can provide excellent palliation (e.g. bone metastasis). Radiotherapy can be delivered at various energy levels (kiloVolts, megaVolts), with various subatomic particles (e.g. electrons, protons, and high-energy electromagnetic radiation). The traditional bulky equipment (e.g. linear accelerator) needs to be housed in an underground bunker and uses complex imaging to improve precision and avoid radiation to normal tissues. Fractionated regimens spanning several days reduce individual doses. Modern techniques using mobile devices (e.g. TARGIT-IORT) can deliver radiotherapy during surgery with the highest precision and immediacy.  相似文献   
9.
Tetrahydrocortisol, -cyclodextrin tetradecasulfate, and minocycline used alone or in combination are not very cytotoxic toward EMT-6 mouse mammary tumor cells growing in monolayer. Tetrahydrocortisol (100 M, 24 h) and -cyclodextrin tetradecasulfate (100 M, 24 h) protected EMT-6 cells from the cytotoxicity of CDDP, melphalan, 4-hydroperoxycyclophosphamide, BCNU, and X-rays under various conditions of oxygenation and pH. Minocycline (100 M, 24 h) either had no effect upon or was additive with the antitumor alkylating agents or X-rays in cytotoxic activity toward the EMT-6 cells in culture. The combination of the three modulators either had no effect upon or was to a small degree protective against the cytotoxicity of the antitumor alkylating agents or X-rays. The Lewis lung carcinoma was chosen for primary tumor growth-delay studies and tumor lung-metastases studies. Tetrahydrocortisol and -cyclodextrin tetradecasulfate were given in a 1:1 molar ratio by continuous infusion over 14 days, and minocycline was given i.p. over 14 days, from day 4 to day 18 post tumor implantation. The combination of tetrahydrocortisol/-cyclodextrin tetradecasulfate diminished the tumor growth delay induced by CDDP and melphalan and produced modest increases in the tumor growth delay produced by cyclophosphamide and radiation. Minocycline co-treatment increased the tumor growth delay produced by CDDP, melphalan, radiation, bleomycin, and, especially cyclophosphamide, where 4 of 12 animals receiving minocycline (14×5mg/kg, days 4–18) and cyclophosphamide (3×150 mg/kg, days, 7, 9, 11) were long-term survivors. The 3 modulators given in combination produced further increases in tumor growth delay with all of the cytotoxic therapies, and 5 of 12 of the animals treated with the 3-modulator combination and cyclophosphamide were long-term survivors. Although neither tetrahydrocortisol/-cyclodextrin tetradecasulfate, minocycline, nor the three modulator combination impacted the number of lung metastases, there was a decrease in the number of large lung metastases. Treatment with the cytotoxic therapies alone reduced the number of lung metastases. Addition of the modulators to treatment with the cytotoxic therapies resulted in a further reduction in the number of lung metastases. These results indicate that agents that inhibit the breakdown of the extracellular matrix can be useful additions to the treatment of solid tumors.Abbreviations 14(SO4)ßCD -cyclodextrin tetradecasulfate - THC tetrahydrocortisol - CDDP cis-diamminedichloroplatinum(II) - 4-HC 4-hydroperoxycyclophosphamide - BCNU N,N-bis(2-chloroethyl)-N-nitrosourea - CAM chick embryo chorioallantoic membrane; IC50, concentration of a drug required to kill 50% of the cells This work was supported by NIH grant P01-CA38493 and a grant from Bristol-Myers-Squibb, Inc., Wallingford, Connecticut  相似文献   
10.
Reliable data from the Bombay Cancer Registry show an increase in the age-adjusted incidence rate of breast cancer in women from 17.9 to 24.9 per 100,000 population between 1965 and 1985. By fitting a linear regression model based on the logarithm of the breast cancer incidence rates, it was found that the average percentage increases in crude, age-adjusted and truncated rates over this 20-year period were highly significant. Evaluation of these trends in the light of proven etiological factors suggests that the increase in breast cancer incidence is related to a gradual decrease in the proportion of women having a first child before 20 years of age and to an increase in the proportion of "never married" women. These findings were also applicable to the subgroup of Hindus (70% of the population) who show a significant increase in breast cancer over this period as well as a clear cohort effect, the younger birth cohorts in general having higher rates than the 5-year older cohorts. However, the Muslim and Christian subgroups were found to have stable rates. An earlier study of cervical cancer incidence over the same period showed stable rates among Muslims and Christians but a declining trend among Hindus. Breast cancer is now the leading cancer in women in Bombay, while cancer of the cervix uteri predominates in the rest of the country. Well-designed epidemiological studies are urgently needed to explain the phenomenon and to help control the increase in breast cancer before it assumes the magnitude observed in the developed countries.  相似文献   
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