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101.
The comparative study of HIV-positive and clinically healthy persons has indicated that the antigens of M. pneumoniae, M. fermentans and U. urealyticum are encountered nearly twice more frequently in the blood of HIV-infected patients than in that of healthy individuals. Mycoplasma antibodies are detected in HIV-positive persons 12 times more frequently than in healthy ones. Among the HIV-infected persons there are those who have simultaneously antigens of some Mycoplasma species.  相似文献   
102.
From 1979 to 1986, 82 infants underwent surgical treatment for necrotizing enterocolitis (NEC), with 36 deaths. The records of 30 of the 36 infants who died were available for review. Fungal colonization and sepsis, the sites of infection, and timing of diagnosis and therapy were determined. Sixteen of 30 (53%) neonates had no evidence of fungus. Six (20%) were colonized with Candida species. Eight (27%) had fungal sepsis, with two of these eight found only at necropsy. Positive fungal blood cultures were a late finding. In only four of the six patients with positive blood cultures were the results known in time to initiate treatment with amphotericin B. Two of these four babies received less than 2 days of amphotericin B treatment prior to death. Fungal sepsis is a significant lethal factor in the surgical mortality of NEC. Vigorous efforts at earlier diagnosis are mandatory.  相似文献   
103.
When children are ill enough to require admission to paediatric intensive care, parents may become distressed about their child's medical condition and this distress may be compounded by the unfamiliar nature of the highly technological environment Parents of children who are sick enough to warrant intubation are particularly likely to be exposed to a frightening array of technological equipment Seventy-one parents of intubated and non-intubated children completed the Parental Stressor Scale Paediatnc Intensive Care Unit (PSS PICU) Overall the findings suggest that parents were most distressed (a) by the painful procedures to which their children were subjected, (b) by the sights and sounds of the intensive care unit and (c) by their children's reactions to intensive care The behaviour of staff towards parents and the way that staff communicated with them caused the least distress When the levels of stress reported by parents of intubated children were compared with those reported by parents of non-intubated children, different patterns of stress were found Painful procedures were a source of greater stress to parents of intubated children whereas the behaviour of staff and the children's reactions to the intensive care experience caused greater stress to the parents of the non-intubated children In general the findings suggest that the needs of parents of non-intubated children are being overlooked, with staff focusing more of their attention on the parents of intubated children  相似文献   
104.
The authors report the clinicopathologic correlation of a patient with non-Hodgkin's mixed-cell lymphoma who had impairment of the circulation of the optic nerve and retina in both eyes. The results of histopathologic examination showed that the pial septa of the optic nerves were infiltrated by lymphoma and that there was extensive infarction of the orbital portions of both optic nerves and occlusion of both central retinal arteries and the right central retinal vein by thrombi with bacteria. The infiltration of the optic nerves seemed to be resistant to therapy.  相似文献   
105.
MHC class II antigens (DR) are not commonly expressed on parenchymal cells of kidney and liver except when they are allografts undergoing rejection. The objective of this study was to determine whether allograft rejection can also induce DR upregulation in parenchymal cells of autologous recipient organs. Dogs had unilateral renal autografts to facilitate kidney sampling. All kidneys were tubular cell DR-negative. After 8-14 days each dog received a tubular cell DR-negative allograft. Tubular cell DR became positive in both allograft and autograft simultaneously, its onset and intensity correlating with blast cell infiltration and rejection in the allograft. Blast cells were first detected in the autograft after allograft nephrectomy, and then disappeared as autograft tubular cell DR diminished over the next 6-8 days. This was reproduced on repeat allografting. In 2 untreated dogs hepatocytes became positive on day 4, with no hepatic blast infiltrate. Four other dogs received cyclosporine immunosuppression. Allograft and autograft tubular cell DR, and hepatocyte DR, increased in all dogs, but were delayed while on CsA until onset of rejection despite transient earlier allograft blast infiltration. Downregulation in autograft and liver occurred together after allograft nephrectomy. An interferon-like substance appeared in plasma after allografting in association with the DR changes in native kidney and liver. Renal allorejection therefore induces upregulation of parenchymal DR expression in autologous liver and kidney of the recipient. It is probably mediated by an interferon-like substance derived from cells infiltrating the allograft. The effect is modified by CsA.  相似文献   
106.
Global and regional cerebral blood flow (CBF) were evaluated with single photon emission computerized tomography (SPECT) utilizing both 133Xenon (133Xe) (47 subjects, 47–82 years old) and 99Tc-hexamethylpropyleneamine oxime (99Tc-HMPAO) (27 subjects, 47–80 years old). The 133Xe results showed: among total subjects, no age-related decline in global CBF, but a significant regional decline in the occipital lobe (p < 0.05); among men, significant age-related declines in global, frontal, temporal, occipital and right hemisphere CBF (all p < 0.05); among women, no age-related decline in global or regional CBF. The 99Tc-HMPAO results showed no age-related decline in either global or regional perfusion among total subjects, men or women. These results suggest that age-related global and regional (including frontal lobe) CBF declines do not occur in healthy control subjects after the age of 45 years. However, gender differences in age-related CBF changes warrant further study.  相似文献   
107.
Limbs of diabetic patients with distal tibial disease are frequently considered unreconstructible; however, when studied with intraarterial digital subtraction angiography, the dorsal pedal artery is frequently found to be patent. We have reviewed our recent experience with 96 patients, 94% of whom had diabetes and had 97 bypasses placed to the dorsal pedal artery. All procedures were for limb salvage. Superimposed infection was present in 42.3%. In 92 instances where intraarterial digital subtraction angiography successfully visualized the dorsal pedal artery, 91 bypasses were placed. In 12 other cases where the dorsal pedal artery was not visualized by intraarterial digital subtraction angiography but audible with the continuous-wave Doppler, bypasses were completed successfully in six. All procedures were performed with vein. Inflow was taken from the femoral artery in 48, popliteal artery in 45, tibial artery in 2, and from a femoral tibial graft in 2. Perioperative mortality was 1.92%. Actuarial graft patency, limb salvage, and patient survival were 82%, 87%, and 80%, respectively at 18 months. We conclude that bypass grafting to the dorsal pedal artery can be reliably performed with acceptable short-term results. An attempt should always be made to visualize the foot vessels angiographically, especially in diabetic patients, so that this valuable option in arterial reconstruction will not be overlooked.  相似文献   
108.
Role of oxidants in microbial pathophysiology.   总被引:19,自引:0,他引:19       下载免费PDF全文
Reactive oxidant species (superoxide, hydrogen peroxide, hydroxyl radical, hypohalous acid, and nitric oxide) are involved in many of the complex interactions between the invading microorganism and its host. Regardless of the source of these compounds or whether they are produced under normal conditions or those of oxidative stress, these oxidants exhibit a broad range of toxic effects to biomolecules that are essential for cell survival. Production of these oxidants by microorganisms enables them to have a survival advantage in their environment. Host oxidant production, especially by phagocytes, is a counteractive mechanism aimed at microbial killing. However, this mechanism may be contribute to a deleterious consequence of oxidant exposure, i.e., inflammatory tissue injury. Both the host and the microorganism have evolved complex adaptive mechanisms to deflect oxidant-mediated damage, including enzymatic and nonenzymatic oxidant-scavenging systems. This review discusses the formation of reactive oxidant species in vivo and how they mediate many of the processes involved in the complex interplay between microbial invasion and host defense.  相似文献   
109.
An outbreak of measles occurred in a community school and the surrounding area in Crowborough, East Sussex, UK, from December 1992 to February 1993. There were 96 suspected cases reported: 66 cases among 1673 students at one school and 30 community cases. The majority of suspected cases were in those aged 11-17 (78%), 2 cases occurred in infants < 1 year old and 8 cases in adults aged 18 years or over. Data collected on 60 (91%) of the 66 suspect school cases showed 56 (93%) had an illness which met a case definition of measles. Eighteen had confirmatory IgM measles antibody. Two cases were hospitalized. The local percentage uptake for measles immunization for the school age years affected varied between 64% and 84%. A survey of parents showed that approximately 74% of the students attending the school had a history of measles immunization. The immunization rates reported by parents for children who developed measles was 21%, (29% based on GP records) compared with 77% for those who remained well. Vaccine efficacy was estimated to be 92%. This outbreak, along with others recently reported in older unimmunized children in the UK, reinforces the need for catch-up immunization programmes to reach this susceptible group of adolescents.  相似文献   
110.
Seventeen patients were entered into a Phase I/II trial of concurrent hyperfractionated radiation therapy (7,440 cGy total dose; 120 cGy b.i.d.) combined with constant infusion of 5-fluorouracil (5-FU) (1,000 mg/m2/24 hours for 72 hours) and cisplatin (DDP) (50 mg/m2) for a total of three cycles. Thirteen patients had Stage IV disease; three, Stage III disease; and one, Stage II hypopharyngeal disease. Thirteen of 17 patients had positive cervical lymph nodes, and the mean size of the largest lymph node was 5.5 x 5.1 cm. The patients were not treated with planned adjunctive surgery except for one patient who had a radical neck dissection for massive, rapidly growing cervical adenopathy, which recurred promptly within 1 month before the initiation of protocol therapy. After the initial six patients were entered, mitomycin-C (Mito 8 mg/m2) was added during the second cycle. All the patients completed the planned course of radiotherapy with a median dose of 7,440 cGy and a mean dose of 7,248 cGy except for two patients who died--one from toxicity and the other, suicide. The predominant toxicity was mucositis, which was grade 3/4 in 11 of 15 patients, resulting in an average interruption of radiation therapy of 12 days. Weight loss was significant and was on the average 12% of baseline weight. Hematological toxicity was mild in the 5-FU/DDP group (only one grade 3 toxicity of six) and severe in the 5-FU/DDP/Mito-treated patients (five of eight patients having grade 3/4 toxicity including one leukopenic pneumonitis death). Additional toxicity included one parapharyngeal cellulitis, which responded to antibiotics. Noncompliance with the complex regimen was only seen in three patients. One patient refused b.i.d. radiation therapy, and one patient refused further chemotherapy after the first cycle. Additionally, one patient who had a severe ethanol withdrawal reaction during the first cycle of 5-FU/DDP did not receive further chemotherapy. The complete response rate of both primary site and neck by the protocol regimen alone was 71%. However, two patients, one from each group, did undergo salvage neck dissection, and the locoregional control is currently 73%, with a mean follow-up time of 18.4 months. The feasibility of combining hyperfractionated radiation therapy with aggressive concurrent chemotherapy was demonstrated. The response and local control rate justifies the added toxicity of concurrent chemotherapy and radiation therapy.  相似文献   
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