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MR thermometry techniques based on the strong water 1H signal provide high spatial and temporal resolution and have shown promise for applications such as laser surgery and RF ablation. However, these techniques have low temperature sensitivity for hyperthermia applications and are greatly influenced by local motion and susceptibility variations. 1H NMR signals from paramagnetic lanthanide complexes of Pr3+, Yb3+ and Tm3+ show up to 300-fold stronger temperature dependence compared to the water 1H signal. In addition, 1H chemical shifts of many of these complexes are insensitive to other factors such as the concentration of the paramagnetic complex, pH, [Ca2+], and the presence of plasma macro-molecules and ions. Applications of lanthanide complexes for temperature measurement in intact animals and the feasibility of mapping temperatures in phantoms have been demonstrated. Among all the lanthanide complexes examined so far, thulium 1, 4, 7, 10-tetramethyl-1, 4, 7, 10-tetraazacyclododecane-1, 4, 7, 10-tetraacetate (TmDOTMA-) appears to be the most attractive for in vivo MR thermometry. The 1H signal from the methyl groups on this complex is relatively intense because of 12 equivalent protons and provides high temperature sensitivity because of the large paramagnetic shifts induced by thulium. The possibility of imaging TmDOTMA2--in intact animals at physiologically safe concentrations has recently been demonstrated. Overall, MR thermometry methods based on hyperfine-shifted MR signals from paramagnetic lanthanide complexes appear promising for animal applications, but further studies relating to acceptable dose and signal-to-noise ratio are necessary before clinical use.  相似文献   
3.
In 1985 a ‘pulse immunization’ project was begunin southern Mozambique, to overcome the difficulties of deliveringimmunization services in rural areas. The project was closelymonitored in order to determine whether this strategy wouldbe appropriate on a national level. Major inputs were in trainingof both health workers and volunteers, and the development ofa system for communications and defaulter tracing via Mozambique'snetwork of grassroots organizations. By 1987 the project hadachieved 60% coverage of fully immunized children in safe ruralareas of the province, having reduced dropout rates betweenfirst and third doses of DPT/OPV from 49% to 11%. This paperdescribes the process of project development through situationanalysis, project design, implementation, monitoring and evaluation.Conclusions are drawn which may be relevant to other programmesin their attempts to accelerate immunization coverage in a sustainableway.  相似文献   
4.
The purpose of this open, prospective, controlled, randomized trial was to study the effect of intermittent, cyclic etidronate on the bone mass of osteoporotic postmenopausal women with or without fractures. Eligible subjects were asymptomatic women less than 75 years old who had been amenorrhoeic for at least 1 year. Those with secondary osteoporosis were excluded. Subjects also had to be ambulant with a bone mineral density (BMD) of the lumbar spine >1 SD below that of age matched controls (Z-score < –1 SD). Eighty patients were enrolled, of whom 65 were recruited through a screening programme conducted in the practices of two general practitioners. The remaining patients were from other referrals. The subjects were randomized to two groups of 40 women. Treatment regimens were as follows. The etidronate group was treated with etidronate 400 mg once daily for 14 days followed by 76 days of 500 mg of elementary calcium once daily; this cycle was repeated every 3 months. The calcium group took 500 mg of elementary calcium once daily. The groups were not different in age, height, weight, time since menopause, BMD at baseline and prevalent vertebral fractures. In 50 patients (28 in the etidronate group and 22 in the calcium group) no vertebral fractures were present (67%). Sixty-four patients (35 in the etidronate group and 29 in the calcium group) completed the 3 years of the study. In the etidronate group the mean BMD of the lumbar spine, femoral neck, trochanter and Ward's triangle increased by 5.7%, 1.4%, 7.1% and 10.9% from baseline values respectively (p<0.05 at all sites except for the femoral neck). In the calcium group no significant changes from baseline were found at any time point at any site after 3 years, except for the femoral neck, where BMD at 156 weeks decreased significantly by 3% (p<0.003). In 3 patients, all in the calcium group, six new fractures were found. There were no serious adverse effects. We conclude that intermittent, cyclic treatment with etidronate causes a significant increase in the BMD of the lumbar spine and the proximal femur in osteopenic postmenopausal women, and that treatment is safe and has no serious adverse effects.  相似文献   
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We report a rare case of early-stage endometrial adenocarcinoma in a 22 year old nullipara with polycystic ovaries undergoing conservative treatment. Pretreatment evaluation including tumour grade, depth of myometrial invasion, tumour size, hormone receptor status and flow cytometric analysis indicated a favourable prognosis. The patient underwent repeat endometrial curettage and a 6 month period of therapy with megestrol acetate and tamoxifen. A combination contraceptive pill was then prescribed to ensure withdrawal of the menstrual cycle thereafter. Now, 1 year after the last curettage, there is no evidence of disease. During the treatment period, hysteroscopy allowed for a more precise approach in panoramically examining the tumour nest in the endometrial cavity, and the subsequent endometrial response to hormone therapy. Laparoscopy using bulldog clamps applied to the isthmic portion of the Fallopian tubes prevented i.p. spread of endometrial tissue from retrograde regurgitation during hysteroscopy. Laparoscopic ovarian electrocautery resulted in the reduction of abnormal hypervascularization on the surface of polycystic ovaries postoperatively but caused a peri-ovarian adhesion complication. It is interesting that this case posed a unique opportunity to demonstrate the tumour regression under the assistance of laparoscopy and hysteroscopy.   相似文献   
7.
FT Chew  DYT Goh  BC Ooi  R Saharom  JKS Hui  BW Lee 《Allergy》1999,54(4):320-329
BACKGROUND: Air-pollution levels have been shown to be associated with increased morbidity of respiratory diseases. METHODS: Data for ambient air-pollutant levels, meteorologic factors, and hospitalization or emergency room (ER) visits for acute asthma in Singapore children over a 5-year period (1990-4) were obtained and analyzed for associations by time-series methods. RESULTS: Throughout this period, the annual mean and 24-h mean levels for sulfur dioxide (SO2), nitrogen dioxide (NO2), and total suspended particles (TSP) and maximum 1-h daily average for ozone were generally within the air-quality guidelines established by the World Health Organization (WHO). However, positive correlation between levels of each of these pollutants and daily ER visits for asthma was observed in children aged 3-12 years, but not among adolescents and young adults (13-21 years old). The association with SO2 and TSP persisted after standardization for meteorologic and temporal variables. An adjusted increase in 2.9 ER visits for every 20 microg/m3 increase in atmospheric SO2 levels, lagged by 1 day, was observed on days when levels were above 68 microg/m3. With TSP, an adjusted increase of 5.80 ER visits for every 20 microg/m3 increase in its daily atmospheric levels, lagged by 1 day, was observed on days with levels above 73 microg/m3. Similar results were also obtained after controlling for autocorrelation by time-series analysis. CONCLUSIONS: These associations were observed even though the overall levels of all pollutants were generally within the air-quality guidelines established by the WHO. These findings suggest that asthmatic children are susceptible to increased levels of air pollutants, particularly SO2 and TSP, although the ambient levels are generally within "acceptable" ranges.  相似文献   
8.
We describe the clinical and laboratory features of a 55-year-old human immunodeficiency virus-negative female patient who presented with bilateral intraocular inflammatory disease (neuroretinitis type) and behavioral changes caused by a Bartonella grahamii infection. Diagnosis was based on the PCR analysis of DNA extracted from the intraocular fluids. DNA analysis of the PCR product revealed a 100% identity with the 16S rRNA gene sequence of B. grahamii. The patient was successfully treated with doxycycline (200 mg/day) and rifampin (600 mg/day) for 4 weeks. This is the first report that demonstrates the presence of a Bartonella species in the intraocular fluids of a nonimmunocompromised patient and that indicates that B. grahamii is pathogenic for humans.  相似文献   
9.
Presumed ocular bartonellosis   总被引:6,自引:0,他引:6       下载免费PDF全文
BACKGROUND: The spectrum of diseases caused by Bartonella henselae continues to expand and ocular involvement during this infection is being diagnosed with increasing frequency. METHODS: The clinical features and visual prognosis for 13 patients with intraocular inflammatory disease and laboratory evidence of bartonellosis were investigated. There were nine patients with neuroretinitis and four with panuveitis with positive antibody titres against B henselae determined by an enzyme immunoassay (IgG exceeding 1:900 and/or IgM exceeding 1:250). RESULTS: Positive IgG levels were found for eight patients and positive IgM levels for five. Despite animal exposure of 10 patients, only two (IgG positive) cases had systemic symptoms consistent with the diagnosis of cat scratch disease. Pathological fluorescein leakage of the optic disc was observed in all affected eyes. At 6 months' follow up, 3/18 (17%) affected eyes had a visual acuity of less than 20/100, owing to optic disc atrophy and cystoid macular oedema. 12 patients (17 eyes) were treated with antibiotics; visual acuity improved two or more Snellen lines for 9/17 (53%) eyes. CONCLUSIONS: The possibility of B henselae infection should be considered in patients with neuroretinitis and panuveitis (especially in cases with associated optic nerve involvement) even in the absence of systemic symptoms typical for cat scratch disease.  相似文献   
10.
Slovick  FT; Abboud  CN; Brennan  JK; Lichtman  MA 《Blood》1985,66(5):1072-1079
The growth of human eosinophil progenitors (CFU-Eo) and the modulation of growth by hydrocortisone were studied as functions of the presence of lymphocytes and monocytes in marrow cells under study; and the source of colony-stimulating factors, specifically, media conditioned by macrophage-like cell line, GCT; phytohemagglutinin-stimulated mononuclear cells (PHA-LCM); or the T cell line, MO. CFU-Eo growth was greatest in marrow containing accessory cells as compared to marrow depleted of accessory cells; and in marrow treated with phytohemagglutinin-stimulated leukocyte conditioned media (PHA-LCM) or MO (T cell line)-conditioned medium (MO-CM) as compared with GCT cell- conditioned medium (GCT-CM). Hydrocortisone reproducibly inhibited eosinophil progenitor growth in unfractionated marrow stimulated by GCT- CM. This effect was abrogated by admixing irradiated mononuclear cells or T lymphocytes with the target marrow or by adding interleukin 1 or interleukin 2 (IL-1, IL-2). Inhibition by hydrocortisone did not occur when monocyte and T lymphocyte depleted marrow was studied. Unlike GCT- CM, MO-CM and PHA-LCM stimulated equal proportions of eosinophil progenitors in nondepleted and accessory cell-depleted marrow and demonstrated less hydrocortisone inhibition. However, both GCT-CM and PHA-LCM produced in the presence of hydrocortisone stimulated significantly fewer CFU-Eos in both unfractionated and accessory cell- depleted marrow target populations. These results indicate that the growth of CFU-Eo and inhibition of growth by hydrocortisone is a direct function of a monocyte-T cell interaction and probably is mediated through effects on the production/release of eosinophil colony stimulating factor (Eo-CSF).  相似文献   
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