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41.
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   
42.
A major complication of cholestasis is fat malabsorption related to decreased intestinal bile acids, which leads to malnutrition and fat-soluble vitamin deficiency. The impaired excretion of bile acids leads to a low intraluminal micellar concentration that causes long-chain triglyceride lipolysis and absorption to be ineffective. Medium-chain triglycerides (MCTs) are more readily absorbed when there are low concentrations of bile acids and therefore are a good source of fat calories; MCTs can be administered as MCT-containing formulas. In those children who are unable to take sufficient calories by mouth, it is important to start nocturnal enteral feeding to improve nutritional status. In infants with cholestasis, the absorption of fat-soluble vitamins (A, D, E and K) that require bile acids is also impaired, and supplementation is mandatory. Vitamin K deficiency may be responsible for hypoprothrombinaemia, which may lead to bleeding diathesis, Vitamin K (phytomenadione) should therefore be promptly administered intravenously, at a dose of 1 mg. Chronic vitamin E (α-tocopherol) deficiency is associated with a progressive neuromuscular syndrome that can cause cerebellar ataxia, areflexia and peripheral neuropathy. Supplements are given orally in doses of 3–5 times the normal requirement if cholestasis is incomplete. In complete cholestasis, supplements must be given intramuscularly at monthly intervals. In infants who fail to thrive, dietary supplements of carbohydrate polymers and MCTs are required.  相似文献   
43.
目的:研究中国健康成年男性志愿者单剂静滴甲磺酸加替沙星注射液的药代动力学。方法:按药物临床试验管理规范(GCP)指导原则设计试验方案。选择9名受试者分别依次单刘静滴100,200和400mg的甲磺酸加替沙星注射液后,应用HPLC测定血药浓度,采用3P97软件进行数据处理,求出药代动力学参数。结果:受试者分别给药后,药-时曲线符合二房室模型,主要药代动力学参数C_(max)分别为1.10±0.19,2.17±0.33和3.16±0.47mg·L~(-1);t_(1/2)β分别为7.42±1.99,8.41±2.72和8.46±2.83h;AUC_(0-∞)分别为4.45 ±0.71,11.10±1.81和23.03±3.83mg h·L~(-1)。原形药主要经肾排泄,48h尿药累积排泄率分别为(43.08±15.79)%,(51.33±23.69)%和(45.67±18.22)%。结论:9名静滴甲磺酸加替沙星注射液后,药-时曲线符合二房室模型。提示甲磺酸加替沙星在100~400mg剂量内药物体内过程基本呈线性动力学特征而无饱和性,主要排泄途径为肾脏。  相似文献   
44.
原发性乳腺恶性淋巴瘤六例临床分析   总被引:8,自引:0,他引:8  
目的 分析原发性乳腺恶性淋巴瘤的临床特点,探讨其诊断、分期和治疗方法。方法回顾分析我院自1995~2002年收治的6例原发性乳腺恶性淋巴瘤和1980~2002年国内主要文献报道的279例原发性乳腺恶性淋巴瘤的临床特征、诊断情况和治疗方法,进行对比分析。结果 285例病例均为非霍奇金淋巴瘤(NHL),免疫学检查证实有282例为B细胞源性(98.9%);女性268例,占94.0%;病灶位于右侧163例,占57.2%;Ⅰ期和Ⅱ期的原发性乳腺恶性淋巴瘤占89.8%。经手术、化疗、放疗等综合治疗后,生存期2~206个月,中位生存期最短23个月,最长56个月。结论 原发性乳腺恶性淋巴瘤绝大部分为B细胞源性非霍奇金淋巴瘤(NHL),Ⅰ期、Ⅱ期多见。对于原发性乳腺恶性淋巴瘤,诊断是关键,确诊后经手术、化疗、放疗等综合治疗,可以获得较长的生存期,疗效十分满意。  相似文献   
45.
Cross sectional studies have reported impaired growth in children with atopic dermatitis. If this growth impairment is irreversible, it would be expected to adversely influence final height attainment. The standing heights and other anthropometric parameters were assessed in 35 adults with onset of atopic dermatitis before 5 years of age and a control group of 35 adults with adult onset contact dermatitis or psoriasis. There was no significant difference in the standing height SD score, mid-parental height SD score, sitting height SD score, subischial leg length SD score, nor body mass index between the atopic dermatitis and control groups. The standing height SD score was not significantly different among: (a) patients with atopic dermatitis affecting less than 50% of their body surface area and those with greater than 50% affected; (b) patients using the four different potency topical corticosteroids; and (c) patients with atopic dermatitis without asthma and those with coexisting asthma. It is concluded that short stature is not a feature of our group of adult patients with onset of atopic dermatitis before 5 years of age, continuing into adulthood, and severe enough to require specialist care. This suggests that if growth impairment occurs in childhood, it is likely to be temporary and reversible.  相似文献   
46.
Background: The purpose of the present paper was to describe the clinical manifestations and treatment of patients with panniculitis. Methods: From January 1983 to December 2002, 4294 patients were treated for pediatric rheumatological diseases at Pediatric Rheumatology Unit, University of São Paulo, Brazil. Of these, 35 children and adolescents (0.8%) presented with panniculitis: erythema nodosum (EN) or Weber–Christian disease (WCD). Clinical characteristics, laboratory exams, biopsy of the lesion, treatment and clinical course were studied. Results: Of the 35 patients, 29 presented with EN and six with WCD, one of these with cytophagic histiocytic panniculitis. Mean age at symptom onset was 85 months (6–204 months) and the mean duration of follow up was 55 months (1–144 months). All the patients presented with inflammatory subcutaneous nodules. The patients with WCD presented with systemic manifestations and cutaneous atrophy. The principal etiologies of EN were streptococcal infection (42%), undetermined (13.5%), pulmonary tuberculosis (10%), and acute rheumatic fever (10%). Biopsy of the nodules indicated septal panniculitis in 14 patients with EN and lobular panniculitis without vasculitis in the patients with WCD, one of which had cytophagic histiocytic panniculitis. There was recurrence in 11 patients (38%) with EN and in all those with WCD. Non‐steroidal anti‐inflammatory drugs were used in 15 patients with EN and corticosteroids and/or immunosuppressive drugs in the six patients with WCD. Three patients died. Conclusions: EN is the most frequent panniculitis, with a benign course and is mainly associated with infections. WCD is a severe disease, with systemic involvement, that proceeds with cutaneous atrophy and requires the use of corticosteroids and or immunosuppressive drugs.  相似文献   
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Primary biliary cirrhosis (PBC) is considered a model autoimmune disease based on several features, including the presence of a highly directed and very specific immune response to mitochondrial autoantigens, a female predominance, a targeted destruction of the biliary epithelium, and homogeneity between patients. It is essentially a chronic progressive cholestatic liver disease characterized by immune‐mediated destruction of small‐ and medium‐sized intrahepatic bile ducts. There is considerable variation in the incidence and prevalence of the disease between regions of the world, although such differences likely reflect not only a true disparity in disease but also differences in awareness; for example, in the United States, PBC is often detected in an asymptomatic stage based on multi‐phasic clinical testing. There has been considerable progress at defining the immune response in this disease, including quantitation of autoreactive T cells against PDC‐E2, the major mitochondrial autoantigen. The overwhelming data suggests that patients develop PBC based on a genetic predisposition and loss of tolerance to one or more environmental agents. In this review, we will present an updated overview of PBC and place it in the context of autoimmunity.  相似文献   
50.
Integrative medicine is a relatively new discipline which attempts to combine allopathic medicine with alternative or complementary medicine, to reap the benefits of both forms of medicine in optimizing the care of patients. Integrative medicine concentrates on treating the patient as a whole, both in body and mind. While the scientific method and “evidence-based” clinical research drives the management and treatment of diseases in conventional Western medicine, alternative or complementary medicine is based on unproven yet potentially beneficial techniques that have been developed throughout history, dating back to the ancient cultures in the Middle East, Africa, and China. In spite of the lack of evidence of most alternative medicine techniques, these methodologies have been practiced for centuries with great acceptance in many countries. It is in the Western world, where “modern” medicine is dictated by the scientific method, that the most controversy in the use of these alternative modes of therapy exists. Since the science behind alternative medicine is incomplete or non-existent, it is difficult for those trained in Western medicine to accept or adopt this approach. But perhaps it is the failure of Western medicine to adequately guarantee our well being and good health that have led to the ongoing debate between the medical profession and the general public as to the benefits of these alternative treatments. In one sense, integrative medicine may be a futile attempt to coin a new term in the hope of legitimizing alternative medicine. On the other hand, there is a wealth of historical experience in the use of the techniques. Studies to evaluate the scientific basis behind ancient medical techniques are ongoing, and it is to be expected that the results will neither be uniformly positive nor negative. Of particular interest is the effect of traditional medicine, herbal formulations, and manipulative techniques on the immune system, and its application in the treatment of autoimmune and allergic diseases. Studies are being designed or conducted to investigate immune effects of herbal formulations or their components. Herbal plants or medicines may lead to skewing of the Th1/Th2 balance in either direction, thus may offer potential application in the treatment of allergic or autoimmune diseases.  相似文献   
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