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41.
Within the rapidly changing climate of primary care, there is an increasing need to evaluate the reactions of patients to real and proposed changes in practice. There are a number of methodologies, both qualitative and quantitative which have been employed to do this. This article presents the methodological problems which may be encountered in evaluating patients' opinions and attitudes in a primary care setting. We begin by discussing the issues which need evaluation, then describe the research process of a recent case study which aimed to evaluate patient satisfaction using a previously validated survey instrument, including the modifications which had to be made to overcome the problems of research in a real life practice setting. We then discuss the strengths and weaknesses of applying different methodological instruments within a primary care setting, and propose a mixed methodological framework as a template for future research which combines the strengths of both large scale survey and small scale qualitative methods to give more insight into the concerns and beliefs of patients as changes occur within their local practice.  相似文献   
42.
Dietary intake during diarrhea in children less than three years of age was estimated from information recorded on illustrated dietary forms used by children's caretakers during the first week of illness in a prospective community-based study of diarrheal diseases in Lima, Peru. The frequency of consumption and the amount consumed of food groups and selected commonly consumed foods were analyzed by the final duration of the diarrheal episode. Cereals were less frequently consumed during the acute phase of diarrheal episodes that ultimately became persistent (>14 days'duration), apparently shortening the duration of the episode by one day (median duration of four days in children not consuming vs three days in children consuming cereals during diarrhea, p <0.02 Kaplan-Meier logrank test). Only roots and tubers (mainly potatoes) were consumed in greater quantity during episodes that became persistent. There was no evidence that consumption of breast milk or non-maternal milk was associated with an alteration in diarrheal duration. This study provides further evidence of the beneficial effects of continuing feeding during diarrhea using foods available at the home level, especially cereals, which are commonly used in the diet of young children.  相似文献   
43.
Bilirubin interferes with the measurement of plasma creatinine by the kinetic colorimetric Jaffe reaction, the method currently used by many hospital laboratories. The purpose of the present study was to evaluate the influence of unconjugated bilirubin on the measurement of plasma creatinine by the AutoAnalyzer Jaffe end point method. This colorimetric method is slower but more precise and accurate in the range of 0.25 to 0.5 mg/dl. We found that bilirubin from jaundiced neonates and from stock solutions did not affect the determination of creatinine chromogen in plasma or in saline, even at concentrations as high as 25 mg/dl. We conclude that the use of the Jaffe end point AutoAnalyzer method with a blank run before each sample will provide an accurate measurement of creatinine in the plasma of the neonate with unconjugated hyperbilirubinemia.  相似文献   
44.
An estimate of glomerular filtration rate has been derived for children from body length (L, in centimeters) and plasma creatinine (Pcr, in milligrams per deciliter): GFR = 0.55 L/Pcr. The near universality of this estimate in children led us to seek a similar formula for estimating GFR in full-term infants during the first year of life. We measured Pcr in 137 healthy infants and performed creatinine clearance (Ccr) studies in 63 of them aged greater than or equal to 5 days. Beyond the first week, Pcr averaged 0.39 +/- 0.01 (0.10 SD) mg/dl. The estimate of GFR from 0.55 L/Pcr overestimated Ccr by 24% (P less than 0.001). Based on the calculation of a new constant from Ccr X Pcr/L, GFR was more accurately estimated from 0.45 L/Pcr (mean difference of Ccr - 0.45 L/Pcr = -0.4 +/- 3.7 (SE) ml/min X 1.73 m2) in full-term infants between 1 and 52 weeks of age. Because the constant 0.45 and Pcr do not change significantly during this period, GFR can be approximated at the bedside from body length of the healthy full-term infant (GFR = 0.45 L/0.39 = 1.1 L).  相似文献   
45.
Analysis of the patterns of stromal cell-derived factor 1alpha (SDF-1alpha) expression in the brains from HIV-positive patients suggests that in neuronal cells, SDF-1alpha might play a role in neuroprotection and neurite extension in response to HIV infection. In all cases analyzed, SDF-1alpha immunoreactivity was primarily present in astroglial cells. Patients with HIV encephalitis (HIVE) showed intense somato-dendritic neuronal SDF-1alpha immunoreactivity, while HIVE negative patients with neurodegeneration had a significant decrease in neuronal SDF-1alpha immunoreactivity. Neuronal cells treated with SDF-1alpha displayed increased neurite outgrowth. Similarly, neurons treated with HIV-Tat, which induced SDF-1alpha expression, also showed neurite outgrowth. Tat-mediated neurite outgrowth was blocked by anti-SDF-1alpha antibody. These results suggest that SDF-1alpha may play a role in the neuronal response to HIV in the brains of AIDS patients.  相似文献   
46.
E mu-pim-1 transgenic mice are predisposed to develop lymphomas. Due to their low spontaneous tumour incidence and their increased sensitivity towards the lymphomagen ethylnitrosourea these mice may present an interesting model for short-term carcinogenicity testing. Here, we report on the further exploration of this transgenic mouse model with two additional carcinogens known to have, among others, the lymphohaematopoietic system as target, i.e. benzo[a]pyrene (B[a]P) and 12-O-tetradecanoylphorbol-13-acetate (TPA). B[a]P, given three times a week (by gavage) for 13 weeks at 4.3, 13 or 39 mg/kg body weight, resulted in a dose-related increase in lymphomas up to a 90% incidence in E(mu)-pim-1 mice during the observation period of 40 weeks. B[a]P also induced tumours of the forestomach within this observation period, though at a lower incidence and apparently equally effective in wildtype and transgenic mice. TPA, on the other hand, was unable to induce lymphomas (or tumours in any other organ) in either transgenic or wildtype animals within the observation period of 44 weeks, when applied dermally at the maximum tolerated dose of 3 microg/mouse, twice a week for 35 weeks. Molecular analysis showed that B[a]P-induced lymphomas in transgenic mice were of T-cell origin, 80% of which had elevated levels of c-myc expression. None of the lymphomas had increased N-myc expression and mutation analysis of the ras-gene family revealed a K-ras mutation in only one out of eight tumours investigated. Also, none of the lymphomas showed aberrant expression of p53 as determined by immunohistochemistry. It is concluded that the E mu-pim-1 mouse model will not be very suitable for short-term carcinogenicity testing in general: only genotoxic chemicals that have the lymphohaematopoietic system as target for carcinogenesis in wild- type mice, appear to be efficiently identified.   相似文献   
47.
Ten haemophilia centres in northern Europe have pooled data on 202 haemophilic children who were infected with HIV between 1979 and 1986. All cases were under 16 years of age on 1 July 1985. The age at infection ranged from 1-15 years. Thirty seven cases (18%) had progressed to AIDS by 1 July 1991 and 15 of these have died. Persistent generalised lymphadenopathy has been noted in 102 patients of whom 18 (17%) have developed AIDS. Twenty three of the remaining patients (23%) have not. CD4+ T cell counts have fallen steadily. Of 36 patients who have had shingles since seroconversion, 19 (53%) had counts below 0.2 x 10(9)/l. Thirty five out of 145 patients without shingles (24%) had similar values. The mean IgA concentration in patients with CD4+ T cell counts above 0.5 x 10(9)/l was 2.38 g/l, between 0.2 and 0.5 was 3.07 g/l, and in those with CD4+ T cell counts below 0.2 x 10(9)/l the mean IgA concentration was 4.58 g/l. Treatment patterns have altered between 1989 and 1991, with increased use of zidovudine in patients without AIDS and a marked increase in primary prophylaxis against pneumocystis pneumonia. This has been associated with a decline in the incidence of pneumocystis as an indicator disease in new AIDS cases from 56% in 1989 to 20% in 1991. These observations indicate that persistent generalised lymphadenopathy does not worsen the outlook, but shingles does. Rising IgA concentrations are markers for disease progression. Modern prophylactic regimens are delaying the onset of indicator disease, but CD4 values continue to fall steadily.  相似文献   
48.
49.
Cytologic smears (CS) were taken from the lateral border of the tongue of HIV-seropositive patients (HIV+) (n = 39) and of seronegative controls (HIV-) (n = 19) and examined by immunocytochemistry (APAAP) and in situ hybridization (ISH) (biotinylated DNA probes) for the presence of viral antigens/DNA of EBV and CMV. While none of the HIV controls showed positive results for EBV antigen, 61% (APAAP) resp. 79% (ISH) of oral epithelial cells in the group of HIV+ patients were EBV-positive. While all CS taken from areas with the clinical diagnosis of hairy leukoplakia (HL) were EBV positive (APAAP and/or ISH), the detection of EBV in CS from uninvolved oral mucosa seemed to be associated with the later development of HL. In the group of HIV+ patients the detection rate for CMV was about five times (APAAP) resp. three times (ISH) higher than in HIV- persons. This non-invasive technique seems to be a valuable tool to screen for viral antigens/genomes.  相似文献   
50.
Risk factors in onychocryptosis   总被引:3,自引:0,他引:3  
A study is described in which the normal toes of 50 patients with unilateral ingrowing toenails were compared with those of 50 healthy subjects matched for age and sex. Twenty-one potential risk factors were compared between the groups. All measurements on patients were derived from unaffected toes in order to avoid anatomical distortion due to the disease process. Statistical analysis revealed significant differences between the groups for three anatomical measures, namely nail fold width (P less than 0.001), medial rotation (eversion) of the great toe (P less than 0.02) and nail thickness (P less than 0.03). Possible discriminating variables were assessed using linear discriminant function analysis and a mathematical equation was derived based on these three factors. This equation was found to possess a potentially high predictive value in that it correctly classified 86 per cent of the patients and 77 per cent of the controls. A further group of 62 unselected patients presenting with unilateral onychocryptosis and 35 unaffected controls were assessed for these three parameters. Of these, 80 per cent of controls and 85 per cent of patients could be classified correctly by the equation. It is thus proposed that, in the majority of subjects with onychocryptosis, a discrete anatomical predisposition exists and that the other factors act only as triggers in the development of the condition. This study provides a rationale for less traumatic surgical approaches to ingrown nail than nail avulsion, with or without nail bed ablation and may also provide a means of identifying high-risk groups.  相似文献   
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