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1.
We have sought to define a way in which nitrous oxide can be safely and universally used at minimal to low flows by utilising a circle system with a controlled leak provided by a standard gas analyser sampling line and a fresh gas supply of 50% nitrous oxide in oxygen, entering from a trunk interposed between the ventilator and the circle system. Although preliminary calculations suggested that this arrangement was likely to work, it was found that 13 of 23 patients studied prospectively developed an inspired oxygen fraction below 0.3. We conclude that, although this arrangement provides a new means of introducing nitrous oxide into the circle breathing system, it does not appear inherently safer or more convenient than the conventional route.  相似文献   
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A follow-up after 2 years on average could be done in 43 cases of pelvic ring injuries. Seven were type A, 8 type B and 28 type C lesions. Every type A lesion was treated non-operatively. External fixation and nonoperative management were used with type B injuries. As well as non-operative treatment, both internal and external surgical techniques were employed for type C fractures. While group A hardly mentioned pain in the follow-up, groups B and C suffered dorsal pelvic pain of comparable intensity irrespective of the therapeutic measures taken. Anatomic reduction does not guarantee freedom from pain. We also rated hip joint flexibility and ability to walk according to the Merle D'Aubigné score. Because of their pelvic injuries 50% of the type C patients changed their profession. The sequelae of the accident on sports and leisure time activities will be considered as well as the subjective contentment evaluated. Unstable and dislocated pelvic ring injuries permanently interfere to a high degree with the quality of life. It is remarkable that many of the traumatic lesions which interfere with the quality of life are caused by the traumatic violence itself and cannot be influenced by the manner of surgical stabilization.  相似文献   
4.
This paper draws on two reviews commissioned by the UK Department for International Development in 2006-2007 that explore progress in linking HIV prevention and maternity services in sub-Saharan Africa. Although pilot and demonstration projects have been successful, progress in scaling up PMTCT has been slow, reaching just 11% of pregnant HIV positive women in much of Africa, less than half the percentage of coverage achieved by antiretroviral treatment programmes for adults in need. Despite ongoing efforts to promote comprehensive approaches, significant policy, financing and institutional barriers, and weak co-ordination and leadership, continue to hamper progress. Maternal health services face human and financial resource shortages which affect their capacity to integrate HIV prevention. Both HIV and maternal health programmes often receive targeted financial and technical assistance that does not take the other into account. However, proposals in 2007 from a number of countries to the Global Fund to Fight AIDS, TB and Malaria incorporate sexual and reproductive health programming that will have an impact on HIV, including certain maternity services. Moreover, Botswana, Kenya and Rwanda have shown that progress can be made where national commitment and increased resources are enabling maternal and newborn care to address HIV.  相似文献   
5.
Atherosclerosis is a systemic disorder and significant lesions often occur in organ systems other than the symptomatic area. Three groups of patients, those admitted to hospital with either coronary artery disease, carotid artery stenosis or peripheral vascular disease, were examined for concomitant atherosclerotic lesions. Non-invasive tests, namely duplex scanning of the carotid arteries, arm ergometer exercise testing, and segmental pressure of the limbs, were used during evaluation. A clear association between ischaemic heart disease, carotid artery stenosis and femoropopliteal disease was found. Women appear to be more prone to multi-organ involvement than men; their higher average age on admission to hospital is a possible explanation for this in some cases, but not all.  相似文献   
6.
People who are prone to motion sickness have a directional preponderance of nystagmus to the left. Centrifuging will change this preponderance to the right in most people, and at the same time reduce their tendency towards motion sickness but only with regard to air travel.  相似文献   
7.
Myofibres in the normal left ventricle (LVs) of 24 healthy young accident victims and the diseased LVs of 10 subjects who died from constrictive pericarditis or congestive (African) cardiomyopathy were subjected to morphometric evaluation. Each myofibre was represented by a pair of measurements: cross-nuclear fibre (FD) and nuclear (ND) diameters. Using a VIDS image analyser interfaced with a light microscope, 150 paired measurements were determined for each of the 34 specimens. The bivariate relationship between FD and ND for each group of specimens were expressed as linear regressions. The limits for the group distribution of normal specimen FD/ND means were calculated and graphically depicted in the form of an ellipse. Disease specimens were plotted for comparison. Of the normal specimens, 23/24 FD/ND coordinates fell within the "normal' ellipse whereas the altered relationship between FD and ND in pathological myocardia caused all 10 specimen means to be plotted outside the ellipse and their regression lines to be displaced from normal. It is suggested that the normal data define the morphometric parameters of LV myofibres in healthy hearts and create a graphic standard by which myofibre pathology in hearts suspected of disease can be detected.  相似文献   
8.
Use of PCR for Diagnosis of Post-Kala-Azar Dermal Leishmaniasis   总被引:2,自引:3,他引:2       下载免费PDF全文
Microscopy and PCR were compared for use in the diagnosis of post-kala-azar dermal leishmaniasis (PKDL) in 63 patients. Aspirates of lymph nodes (samples from 52 patients), skin (23 samples), and bone marrow (18 samples) were used. For 11 patients lymph node aspiration could be repeated 6 months after they recovered from PKDL. During active PKDL, PCR was positive for 42 of 52 (80.8%) lymph node aspirates and 19 of 23 (82.7%) skin aspirates, whereas microscopy was positive for only 9 of 52 (17.3%) lymph node aspirates and 7 of 23 (30.4%) skin aspirates. PCR was always positive when parasites were seen by microscopy. When the results obtained with lymph node and skin aspirates from the same patient (n = 16) were compared, there was complete agreement. Bone marrow samples were negative by microscopy and PCR for 16 patients and positive by both methods for 1 patient; for one sample only the PCR was positive. PCR confirmed the co-occurrence of visceral leishmaniasis and PKDL in one patient and confirmed the suspicion of this co-occurrence in the other patient. After recovery, no parasites were found by microscopy, but 2 of 11 (18.2%) samples were still positive by PCR. Thirty negative controls were all found to be PCR negative, and 15 positive controls were all PCR positive. Cross-reactions with Mycobacterium leprae could be ruled out. In conclusion, PCR with inguinal lymph node or skin aspirates is suitable for confirming the clinical diagnosis of PKDL. In some patients, lymph node aspirates are probably preferred because aspiration of material from the skin may leave scars.  相似文献   
9.
In this study the efficacy of treatment of two cyclo-oxygenase inhibitors, ibuprofen (Ibu) and indomethacin (Indo), are compared in the immunotherapy of metastasis designed to reverse prostaglandin E2 (PGE2)mediated inactivation of interleukin-2 (IL-2)-dependent host killer cell lineages. These agents were tested either alone for the prevention of metastasis or in combination with IL-2 for the eradication of established metastasis. C3H/HeN mice were placed on chronic oral Ibu (CIbT; 200 and 600 ,g/ml of water) or Indo (CIT; 10 g/ml) 5 days after s.c. transplantation of 5 × 105 metastatic C3L5 mammary carcinoma for the prevention of spontaneous lung metastases. They showed intolerance to Indo at a dosage of 14 g/ml, which was well tolerated by other mouse strains in previous studies, but tolerated the Ibu dosages used. Control and treated mice were killed on day 30 to score metastatic lung colonies, to evaluate killer activity in splenocytes against natural killer (NK)-sensitive YAC-1 lymphoma or NK-resistant C3L5 adenocarcinoma and 8911 lymphoma targets, and to phenotype the surface markers of killer cells. CIbT and CIT alone at the above dosage significantly reduced the number of lung colonies, retarded local tumor growth and restored NK activity of splenic killer cells expressing AGM-1+, Thy-1, Lyt-2 phenotype. To treat established lung metastasis, mice bearing 15-day C3L5 transplants were given CIbT or CIT alone or in combination with two 4-day rounds (days 20–23, 31–34) of IL-2 (15 000 Cetus units, i.p. every 8 h) and were killed on day 35 to score lung colonies and characterize splenic killer cells. CIbT or CIT alone reduced the number of spontaneous lung metastases and restored anti-YAC-1 killer function of splenocytes with NK-like phenotype (AGM-1+, Thy-1, Lyt-2); some anti-C3L5 killer function was also generated in the high dose Ibu group and the killer cell showed AGM-1+, Thy-1+ and Lyt-2+ phenotype. Combined therapies with CIbT or CIT plus IL-2 were more effective in reducing metastases and promoting killer cell function, the best results being achieved with high dose Ibu + IL-2. All killer cells expressed AGM-1 and Thy-1. In addition, C3L5 killer cells also expressed Lyt-2, suggesting T-cell stimulation. PGE2 synthesis in the host was inhibited by at least 50% in mice subjected to CIbT or CIT. Thus, Ibu proved to be an excellent substitute for Indo in preventing metastasis and NK cell activation when given alone, and also in ameliorating established metastasis and activating lymphokine-activated killer cells when combined with IL-2.  相似文献   
10.
X-linked congenital stationary night blindness (CSNBX) is anon-progressive retinal disorder characterized by decreasedvisual acuity and loss of night vision. CSNBX Is clinicallyheterogeneous with respect to the involvement of retinal rodsand/or cones in the disease. in this study, we localize a newlocus for CSNBX to Xp21.1, thus providing evidence that CSNBXis also genetically heterogeneous. A clear correlation betweendifferent genotypes and phenotypes cannot be found yet. Thenew CSNBX gene described here is closely linked to the X-linkedretinitis pigmentosa type 3 gene region, which supports thehypothesis that there may be a functional relationship betweencongenital stationary night blindness and retinitis pigmentosa.  相似文献   
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