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101.
目的 体外比较曼氏血吸虫吡喹酮敏感株与抗性株成虫阶段对吡喹酮的反应性。方法 将各虫株成熟成虫分别培养于含吡喹酮分别为 3.2× 10 - 4、8× 10 - 4、1.6× 10 - 3m ol/ L的 MEM培养液中 ,37℃孵育 15、30、4 5、6 0、75 min后 ,分别在解剖镜下观察虫体的存活状况并计算存活率。结果 当孵育于含吡喹酮 3.2× 10 - 4m ol/ L的 MEM中 75 m in,敏感株与抗性株雌虫均能存活 ;但敏感株与抗性株雄虫的存活率仅为 11.5 % - 16 .0 %和 32 .7% - 36 .5 %。孵育于含吡喹酮 8× 10 - 4m ol/L 的 MEM中 15 min,抗性株雄虫与雌虫存活率为 4 8.3% - 5 0 .0 %和 5 7.9% - 6 3.6 % ;敏感株雄虫与雌虫的存活率为 2 2 .4 % - 2 5 .9%和 38.5 % - 4 8.3% ;75 min后 ,抗性株雄虫的存活率为 13.3%- 17.3% ,敏感株雄虫的存活率则为 0。孵育于含吡喹酮 1.6× 10 - 3m ol/ L 的 MEM中 15 min,抗性株雄虫与雌虫的存活率为 11.1% - 19.6 %和 2 7.5 % - 2 9.9% ;敏感株雄虫与雌虫的存活率均为 0。结论 将曼氏血吸虫吡喹酮抗性株和敏感株成虫孵育于含一定浓度吡喹酮的 MEM中不同时间后 ,抗性株的存活率高于敏感株 ;雌虫的存活率高于雄虫  相似文献   
102.
The mortality rate of elderly persons with heart failure is high despite the introduction of several effective therapeutic interventions during the past decade. The management of end of life, often associated with distressing symptoms and multiple hospitalizations, is a significant clinical problem. Skillful and effective management requires expert knowledge of the heart failure syndrome, but the critical dimension of care relates to detailed knowledge about a patient's comorbidities, extent of debility, values, and desires. Discussing end-of-life issues early in the course of illness is essential for determining the appropriate levels of intensity of care and for defining the circumstances in which patients wish to be hospitalized and when hospital care offers little potential for increased comfort or longevity. Early and repeated discussions are needed to consider matters such as living wills, do-not-resuscitate orders, and power of attorney. In light of the complexity of the health care system, including involvement of multiple caregivers, end-of-life issues are among the most demanding of a physician's time, but when end-of-life care is managed effectively, health care providers often are rewarded with the gratitude of patients and their families for minimizing suffering and providing optimal opportunities for patients to participate in the affairs of family and the community.  相似文献   
103.

Background and purpose:

It has been previously shown that high levels of nitric oxide (NO), from NO donors, kill neurones, but the mechanisms are unclear.

Experimental approach:

The effects of NO donors on the electrical properties of rat cultured cerebellar granule cells (CGC neurones) were investigated using the whole-cell patch-clamp technique.

Key results:

The NO donor (Z)-1-[2-(2-aminoethyl)-N-(2-ammonioethyl)amino]diazen-1-ium-1,2-diolate (DETA-NONOate or NOC-18) caused a rapid, persistent, but fully reversible inward current that was associated with an increase in baseline noise and was concentration dependent (100 µM–10 mM). The response to 3 mM DETA-NONOate was completely inhibited by 1 mM gadolinium, but not by NO scavengers (1 mM haemoglobin or 1 mM PTIO) or glutamate receptor antagonists (10 µM MK-801 or 60 µM CNQX). Application of decomposed 3 mM DETA-NONOate or 3 mM nitrite had no effect. In contrast, the NO donor S-nitrosoglutathione (GSNO) caused a rapid, persistent, but fully reversible outward current that was also concentration dependent (1–10 mM). The 3 mM GSNO response was unaltered by NO scavengers, glutamate antagonists or gadolinium, but was mimicked by decomposed 3 mM GSNO and 3 mM oxidized glutathione.

Conclusions and implications:

These results suggest that DETA-NONOate directly activates cation-selective channels, causing an inward current in CGCs. In contrast, GSNO causes an outward current in these cells. Some of the effects of these NO donors are independent of NO, and thus caution is required in interpreting results when using high concentrations of these compounds.  相似文献   
104.
We report a 62-year-old man with documented type 2 diabetes mellitus and hypertension, who presented with a rapid deterioration in renal function. The sudden decrease in renal function in this well-controlled diabetic patient prompted us to consider a nondiabetic and nonhypertensive cause. The urinary sediment showed a glomerular haematuria suggestive of glomerulonephritis. A diagnosis of fibrillary glomerulonephritis was made on renal biopsy. Fibrillary glomerulonephritis is a rarely diagnosed disease with clinical manifestations such as proteinuria, microscopic haematuria, nephrotic syndrome and impairment of renal function. A diagnosis of fibrillary glomerulonephritis can only be made by electronmicroscopy of the renal tissue. In this case report the spectrum of this disease is reviewed.  相似文献   
105.
106.
A 62 year old Chinese woman presented 25 years after having both breasts augmented with paraffin injections. Development of paraffinomas and multiple episodes of paraffin-related mastitis eventually resulted in bilateral mastectomies. The unusual distribution of migrated calcified paraffinomas in the thoracic wall and its lymphatic system is documented on computed tomography.  相似文献   
107.
Fifteen patients with infantile bone and joint infections were studied immunologically and clinically, 3 at the time of illness and 12 later. Abnormality of immunoglobulins, or complement, or phagocytes was found in 9 patients; 6 were within normal limits for the tests undertaken. Immunodeficiency is probably responsible for the subdued clinical signs of infection and for delayed diagnosis in some patients. It was also related to the extent of femoral head damage in infective arthritis of the hip and to the incidence of wound infection in late elective surgery.  相似文献   
108.
Preterm birth remains one of the serious problems in perinatal medicine and is associated with an increased risk of neonatal complications and long-term morbidity. Although each day that delivery is delayed between 22 and 28 weeks of gestation increases survival by 3%, since most spontaneous preterm labour occurs between 28 and 34 weeks of gestation, this is of secondary concern; the primary goal of delay is to improve the function of certain systems in the fetus and to balance the risks of a hostile intrauterine environment with the complications of extrauterine preterm life. Although there is a lack of definitive evidence that tocolytic drugs improve outcome following spontaneous preterm labour and preterm birth, there is ample evidence that tocolysis delays delivery for long enough to permit administration of a complete course of antepartum glucocorticoids and to facilitate in utero transfer to a tertiary care unit where neonatal care will be optimal. Both these measures have been associated with improved outcomes; antepartum glucocorticoids reduce the incidence of respiratory distress syndrome, intraventricular haemorrhage, periventricular leucomalacia and necrotising enterocolitis, and in utero transfer is associated with decreased morbidity and mortality and less hospital-based intervention compared with postnatal transportation. Consequently, women who are more likely to benefit from tocolysis are those at early gestational ages, those needing transfer to a hospital that can provide neonatal intensive care and those who have not yet received a full course of antepartum glucocorticosteroids. In these cases, delaying labour for at least 48 hours with drugs such as atosiban should be considered, since it offers clear advantages for the fetus.  相似文献   
109.
A survey on the burden and quality of care and the parental and primary care physicians'views on management of eight chronic illnesses and disabilities was conducted from 1990 to 1993. Data were collected on 993 children and adolescents from family interviews and physicians'postal questionnaires. Approximately 70% of patients used two or more services for care management and 149 children were treated outside their region. Only 36% of the physicians were case managers and half of these agreed that better communication with other care providers could facilitate their role. A wide difference in parental satisfaction was found between medical and disabling conditions. Approximately 90% of the parents expressed satisfaction with care for children with coeliac disease (112/120), asthma (80/89) and diabetes (98/111), whereas approximately one-third of parents of children with cerebral palsy and Down's syndrome were dissatisfied (88/242 and 72/189, respectively). Primary care physicians expressed similar satisfaction with case management. Distance from hospital, the need for more information on disease management and financial aid were the sources of greatest dissatisfaction. Children with disabling diseases had more problems integrating at school than children with other chronic disorders. Closer interaction between health services, providers and families is necessary to manage the needs of disabled (Italian) children better. Chronic illness, disability, family, primary care, quality of care, special needs  相似文献   
110.
The presence of Fc receptors for IgE on epidermal Langerhans cells (LC) from patients with atopic dermatitis (AD) was demonstrated by three different types of experiments. Firstly, cell-bound IgE on LC was removed by acid elution and restored by highly purified human myeloma IgE (IgE kappa). Secondly, after pepsin digestion of cell-bound IgE the number of LC staining with anti-human light chain (kappa, lambda) antibodies significantly decreased in contrast to the number of LC staining with anti-human epsilon heavy chain antibody. Thirdly, LC formed rosettes with sheep red blood cells (SRBC) coated with IgE kappa. Epidermal LC from normal non-atopic controls, did not form rosettes with SRBC-IgE. The SRBC-IgE rosette formation could be inhibited by preincubation with IgE kappa and BB10 (MoAb directed against the Fc receptor for IgE on human eosinophils, platelets and macrophages), but also with human IgG, whereas the SRBC-IgG rosette formation could be inhibited neither by IgE kappa nor by BB10. Both the SRBC-IgE and the SRBC-IgG rosette formation could be inhibited by OKT6 (anti-CD1) antibody. The results of inhibition studies with OKT6 antibody on the reconstitution of IgE on epidermal LC after acid elution suggest an associated expression of the CD1 antigen and the Fc receptor for IgE.  相似文献   
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