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41.
Aqueous, ethanolic and hexane extracts of the leaves of Nauclea latifolia (Rubiaceae) were assessed for their fasting blood glucose lowering effect in normoglycaemic and streptozotocin - diabetic rats. Wistar strain albino rats were given different doses of the extracts after 18 hrs fast and their blood glucose measured at 0,1,2,4 and 6 hours after treatment. The aqueous and ethanolic extracts significantly lowered the fasting blood glucose levels of the STZ-diabetic rats in a dose-dependent manner. The highest dose administered (400mg/kg) lowered the fasting blood glucose of the diabetic rats by 31.7% (aqueous) and 36.1% (ethanolic) extracts. The aqueous extract did not significantly lower the glucose levels of normoglycaemic rats (maximum 6.6%), nor was any significant decrease seen in the rats administered with the hexane (maximum of 4.0% for normoglycaemic and 2.4% for diabetics) extract. The hypoglycaemic and antihyperglycaemic potentials of the aqueous and ethanolic extracts were comparable to that of glibenclamide (1mg/kg).These results further support the traditional use of the plant in the treatment of diabetes mellitus.  相似文献   
42.
Summary. Satellite RNA was sought in 51 isolates of Rice yellow mottle virus (RYMV) representative of the geographical, molecular and pathogenic variability of the virus in Africa. Three-quarters of the isolates from cultivated rice and wild gramineaceous hosts supported a satellite RNA. The prevalence of RYMV isolates that were associated with a satellite differed among regions, being c. 100% in West and Central Africa and c. 36% in East Africa. The RYMV satellite showed a low diversity as only seven of the 220 sequenced positions were variable. One insertion also occurred after serial host passages of the satellite. Two forms of the satellite differed by six substitutions forming three base pairs in one branch of the predicted RNA secondary structure. There was no evidence of intermediates between these two forms, but double-infection occurred. Each form had a specific geographical distribution: one occurred in Central Africa, the other elsewhere in Africa. There was no relation between the occurrence or the forms of the satellite and the phylogeny of the helper virus. The satellite was not involved in symptom modulation or ability to break host-plant resistances to the disease.Received January 29, 2003; accepted April 12, 2003 Published online June 24, 2003  相似文献   
43.
Breast fat necrosis (BFN) is usually a benign inflammatory response to breast trauma. However, an extremely rare cause of fat necrosis is calciphylaxis, a calcification of small- and medium-sized arteries causing thrombosis and ischemia. It is classified into (A) uremic (B) nonuremic-induced calciphylaxis. Calciphylaxis has been reported to be encountered in different parts of the body. However, to the best of our knowledge there is only one case in the English literature of BFN 2ry to warfarin-induced calciphylaxis. We report a 65-year-old female, known case of atrial fibrillation on warfarin, presented with a left breast mass of 4-month duration. The mass was painful and progressively enlarging. Examination of the left breast showed 7 × 4 cm mass, spanning from 10-2 o'clock, free from surrounding structures, with preserved overlying skin. However, the mass was not visualized on mammogram. Ultrasound showed a left breast lobulated hypoechoic mass containing a hyperechoic component. Biopsy showed fat necrosis. After 1 month, she presented with ulceration of the overlying skin. After wide local excision, histopathology demonstrated a calciphylaxis-induced fat necrosis. Considering the patient's background, the diagnosis was BFN secondary to warfarin-induced calciphylaxis. Hence, the warfarin was shifted to Rivaroxaban, 6 months follow-up showed no evidence of recurrence. In conclusion, the rarity of nonuremic calciphylaxis is reflected on the delay of diagnosis in some of the reported cases and the lack of grading system used to guide the management of such difficult wounds. However, keeping a high index of suspicion is important whenever such wounds are encountered with presence of risk factors other than end-stage kidney disease.  相似文献   
44.
Rhabdomyosarcoma (RMS) is a common malignancy in children, but embryonal rhabdomyosarcoma (ERMS) deposits rarely occur in the breast in adults. Therefore, little is known about magnetic resonance imaging (MRI) features of breast metastases from RMS, especially the embryonal type. We reported a case of a 22-year-old woman who was diagnosed with ERMS at left foot 2 years ago and accepted operation and chemotherapy. She was confirmed to have breast metastases from the left foot. Successive imaging examinations were performed 3 months apart. Breast ultrasound indicated a benign lesion, and further examination did not reveal any bone metastases. However, predominant restricted diffusion and rim contrast enhancement on MRI combined with the patient's medical history suggested a malignancy of BI-RADS 5. After 3 months, breast ultrasound revealed masses detected last time became larger and lobulated. In addition, internal heterogeneous intensity and rim contrast enhancement with restricted diffusion were revealed on MRI. We speculated that typical MRI findings of breast metastases from RMS may include iso- to hypointensity on T1WI, heterogeneous hyperintensity on T2WI, and circular enhancement with restricted diffusion. Moreover, mild peritumoral edema, rapid expansion of necrosis, and ascending time-intensity curve detected on MRI may be features of the ERMS type.  相似文献   
45.
Self-care enables patients in improving quality of life and reducing hospital admissions. Research explored the experiences of patients about breathlessness, sleep problems and complication management in chronic obstructive pulmonary disease (COPD). However, the self-care experiences and the role of the family in self-care are underexplored. This study aimed to understand the self-care experiences of patients with COPD and explore the role of the family in self-care. An interpretive phenomenological inquiry was used, and 13 patients were interviewed in 2019 from two hospitals in Pakistan. The inclusion criteria were patients above 30 years of age at any stage of COPD, who received a confirmed diagnosis of COPD and were receiving the treatment, and engaged in self-care at their homes or communities. The interviews lasted for 35–60 min. Ricoeur's interpretation theory was used for data analysis comprising steps explanation, naive understanding and in-depth understanding. Self-care emerged as a complex individual and familial endeavour affected by personal, social and economic factors. Poverty was one of the core determinants of self-care. Patients emphasised the spiritual, cultural and traditional approaches to self-care. Future research is warranted to develop better understanding of spiritual and cultural self-care and how these dimensions of self-care affect patients’ self-care behaviours.  相似文献   
46.
Young people from migrant and ethnic minority backgrounds are recognised as emerging priority populations for reducing alcohol and other drug (AOD)-related harms in Australia. Limited research has investigated how service providers address AOD challenges in migrant communities. In this qualitative study, we interviewed 15 service providers from AOD, migrant support, community and other health services in a diverse region of Melbourne. Interviews explored the challenges that service providers faced and the strategies they implemented to engage with young migrants in relation to AOD use. Thematic analysis was used to generate four themes: stigma as a barrier to service delivery, intergenerational differences between young people and parents, the need for outreach and establishing trust and understanding over time. Service providers believed that stigma prevented many young people from migrant backgrounds having open conversations about their AOD use with family members and professionals. Participants perceived that some parents had less AOD-related knowledge and lower English language proficiency than their children creating challenges for effective communication. Service providers recognised the importance of engaging with young people in settings where they felt comfortable rather than expecting them to approach their service. Participants also acknowledged the need to invest time in establishing trust and understanding with young migrants so they could facilitate conversations about AOD use as relationships evolved. Although service providers had a strong understanding of young people's needs, they found it challenging to build relationships in the context of funding and time constraints. Our results indicate the need for long-term funding and timelines that enable service providers to build strong relationships with young migrants, their families and their broader cultural communities to facilitate access to AOD support.  相似文献   
47.
Objective. The objective of our study was to determine if clinical observation of pressure-flow relationships (PFR) can differentiate between partial external obstruction (obstruction) and infiltration as a cause of poor performance of gravity-fed infusions.Methods. A total of 24 patients with functional intravenous cannulae in situ had obstruction simulated by the application of a tourniquet proximal to the cannula. The change in flow (F) for a discrete change in pressure (P) was determined in each case by counting drop rates at two different elevations of the fluid reservoir level, 10 cm apart. The same process was repeated in 15 patients in whom the cannula was in an extra vascular location (infiltration). Three sizes of cannula—16-gauge, 18-gauge, and 20-gauge—were examined, with equal distribution of sizes in each group. The effect on flow rates of inflating a blood pressure (BP) cuff proximally on the cannulated limb was assessed. The ratio P/F is the total resistance of the infusion system, and by subtracting known values for resistance of infusion tubing and cannula, the venous or tissue resistance was calculated.Results. There was a statistically significant difference between the change in flow for obstructed compared with infiltrated cannulae for the same change in pressure for each cannula size. The mean venous resistance was 23 mm Hg/L/hr, while that of tissue was 280 mm Hg/L/hr, with no overlap between groups. There was no effect on flow rate with blood pressure cuff inflation in the infiltrated group whereas flow progressively fell in the obstructed group.Conclusions. Clinical observation of PFRs in poorly functioning gravity-fed IV infusions can assist in detecting infiltration as a cause. Inflation of a blood pressure cuff will further impair flow where the cannula is intravascular, but will have no effect in an extravascular location.  相似文献   
48.
Varieties of gastric surgery have increasingly been used in the management of morbid obesity. Generally, however, research and commentary in this area have related to surgical technique, with weight loss or morbidity being regarded as the most important dependent measures. In the context of the publication of several papers relating to the effects of surgery in the long-term, we believe that it is timely for surgeons to examine their criteria for success. In this paper, we argue that weight loss is inadequate as a primary criterion for success in this context, and that the value of the intervention should be measured against a multidimensional concept of success.  相似文献   
49.
There has been a prolific growth of voluntary organizations in India since independence in 1947. One of the major areas of this growth has been in the field of community health. The purpose of this article is to historically trace the voluntary movement in community health in India, analyze the current status, and predict future trends of voluntary efforts. A review of the literature in the form of a Strengths, Weaknesses, Opportunities, and Threats (SWOT) analysis was the method of this study. Some of the key trends which emerged as the priority areas for progress and for strengthening voluntary organizations in the future were enhancing linkages between health and development; building upon collective force; greater utilization of participatory training; establishing egalitarian and effectual linkages for decision making at the international level; developing self-reliant community-based models; and the need for attaining holistic empowerment at individual, organizational, and community levels through duty consciousness as opposed to merely asking for rights.The authors would like to express gratitude to Voluntary Health Association of India for sharing the necessary documents and to Dr. Rick Petosa for valuable editorial comments.  相似文献   
50.
Objectives. To examine relationships between body mass index (BMI) and cardiovascular risk factors in 279 Europeans and 231 Polynesian Pacific Islanders in New Zealand.

Methods. Participants were recruited from Seventh‐Day Adventist church meetings or camps, and were surveyed by self‐administered questionnaire. Blood pressure, weight and height were measured. Fasting blood samples were analysed for lipids, glucose and fructosamine.

Results. Age‐adjusted BMI was higher in Pacific Islanders than in Europeans: 32.8(0.3) versus 25.6(0.3); means(SE); p = 0.0001). In Europeans, BMI was positively associated with systolic and diastolic blood pressures, triglycerides, total cholesterol, LDL cholesterol and fasting blood glucose, and negatively associated with HDL cholesterol. In Pacific Islanders, BMI was associated only with systolic and diastolic blood pressures, and with HDL cholesterol. These associations were stronger in Europeans than in Pacific Islanders.

Conclusions. In this group of Pacific Islanders, the association between BMI and cardiovascular risk factors was weaker than in Europeans. This suggests that either BMI is a poor measure of adiposity in Pacific Islanders, or that adiposity may be less strongly linked to cardiovascular disease in Pacific Islanders.  相似文献   

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