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71.
72.
OBJECTIVE: Adrenal failure, a treatable condition, can have catastrophic consequences if unrecognized in critically ill ED patients. The authors' objective was to prospectively study adrenal function in a case series of hemodynamically unstable (high-risk) patients from a large, urban ED over a 12-month period. METHODS: In a prospective manner, critically ill adult patients presenting to the ED were enrolled when presenting with a mean arterial blood pressure < or =60 mm Hg requiring vasopressor therapy for more than one hour after receiving fluid resuscitation (central venous pressure of 12-15 mm Hg or a minimum of 40 mL/kg of crystalloid). Patients were excluded if presenting with hemorrhage, trauma, or AIDS, or if steroids were used within the previous six months. An adrenocorticotropic hormone (ACTH) stimulation test was performed and serum cortisol was measured. Treatment for adrenal insufficiency was not instituted. RESULTS: A total of 57 consecutive patients were studied. Of these, eight (14%) had baseline serum cortisol concentrations of <20 microg/dL (<552 nmol/L), which was considered adrenal insufficiency (AI). Three additional patients (5%) had subnormal 60-minute post-ACTH-stimulation cortisol responses (<30 microg/dL) and a delta cortisol < or =9 microg/dL, which is the difference between the baseline and 60-minute levels. This is functional hypoadrenalism (FH). There were no laboratory abnormalities that distinguished patients with AI or FH from those with preserved adrenal function (PAF). Rates of survival to discharge did not differ between the AI group (7 of 8) and PAF patients (21 of 46; p = 0.052). CONCLUSIONS: Adrenal dysfunction is common in high-risk ED patients. Overall, it has a frequency of 19% among a homogeneous population of hemodynamically unstable vasopressor-dependent patients. The effect of physiologic glucocorticoid replacement in this setting remains to be determined.  相似文献   
73.
Lipid targets can be difficult to attain in familial hypercholesterolaemia. To compare atorvastatin with simvastatin- fenofibrate and simvastatin-cholestyramine therapy, we studied 54 patients with familial hypercholesterolaemia over periods of 2-6 months on each therapeutic regimen. The atorvastatin regimen reduced total cholesterol by 41.2 +/- 11.2%, LDL by 45.6 +/- 15.5%, triglycerides by 33.8 +/- 24.8%, and increased HDL by 2.3 +/- 37.0%. Simvastatin- fenofibrate therapy achieved reductions of 33.9 +/- 8.5% in cholesterol, 42.0 +/- 12.2% in LDL, 34.7 +/- 38.3% for triglycerides, and a 25.4 +/- 55.1% increase in HDL. Simvastatin-cholestyramine gave a reduction of 31.3 +/- 11.8% in cholesterol, 36.0 +/- 14.4% in LDL, 13.7 +/- 36.3% in triglycerides, and a 1.1 +/- 30.3% rise in HDL. The atorvastatin regimen was marginally but not significantly better than simvastatin-fenofibrate in improving the LDL:HDL ratio, LDL:apoB and and apolipoprotein B:A1 ratios. Eleven patients (20.4%) had side- effects: two discontinued atorvastatin due to side-effects; two patients had rashes; six had myalgia and two had diarrhoea. Gastrointestinal side-effects were described in 16 (30.1%) patients on simvastatin-cholestyramine therapy and four cases of myalgia (11.2%) were seen with simvastatin-fenofibrate. In nine patients on atorvastatin (20.4%) a 30% or greater fall in HDL was observed, compared to five patients with resin therapy (9.2%) and two with fibrate therapy (5.5%). There were no significant differences in liver or muscle biochemistry between the regimens, but atorvastatin did raise transaminase and creatine kinase concentrations significantly compared to pre-treatment values (p = 0.001). Atorvastatin significantly improves the lipid profile in most patients compared with other regimens. It has a comparable incidence of side-effects to combination therapy regimens.   相似文献   
74.
The present study shows that the ability of soluble immune complexes (IC), prepared with human IgG and rabbit IgG antibodies against human IgG, to trigger platelet activation was markedly higher for IC prepared with cationized human IgG (catIC) compared with those prepared with untreated human IgG (cIC). CatIC induced platelet aggregation and adenosine triphosphate release in washed platelets (WP), gel-filtered platelets (GFP), or platelet-rich plasma (PRP) at physiologic concentrations of platelets (3 x 10(8)/mL) and at low concentrations of catIC (1 to 30 micrograms/mL). On the contrary, under similar experimental conditions, cIC did not induce aggregation in PRP, WP, or GFP. Low aggregation responses were only observed using high concentrations of both WP (9 x 10(8)/mL) and cIC (500 micrograms/mL). Interestingly, catIC were also able to induce platelet activation under nonaggregating conditions, as evidenced by P-selectin expression. Cationized human IgG alone did not induce platelet aggregation in PRP but triggered either WP or GFP aggregation. However, the concentration needed to induce these responses, was about eightfold higher than those required for catIC. The responses induced either by catIC or cationized human IgG were completely inhibited by treatment with heparin, dextran sulphate, EDTA, prostaglandin E1, or IV3, a monoclonal antibody against the receptor II for the Fc portion of IgG (Fc gamma RII). The data presented in this study suggest that IgG charge constitutes a critical property that conditions the ability of IC to trigger platelet activation.  相似文献   
75.
Remission following an elemental diet or prednisolone in Crohn's disease   总被引:1,自引:0,他引:1  
The short- and long-term effects of an elemental diet in children with acute Crohn's disease were compared with those of prednisolone in historical controls. Clinical remission was induced in 25 of 30 and in 18 of 28 episodes treated for six weeks with an elemental diet and prednisolone. Patients with proximal disease had longer remission after treatment with an elemental diet (p < 0.05) than did patients with colonic disease after treatment with prednisolone (p < 0.01). Disease activity index score improved in both groups compared with the pretreatment scores (p < 0.05). However, the improvement in the elemental diet group was significantly better than in the prednisolone group (p < 0.001). Changes in linear growth were better after treatment with an elemental diet compared with steroids (p < 0.001). Serum albumin and haematocrit concentrations all improved significantly in the children treated with an elemental diet (p < 0.001) but not in those treated with steroids. Thus an elemental diet was better than prednisolone in proximal disease and confirmed improved growth and nutritional status.  相似文献   
76.
Pelvic ultrasound findings in different forms of sexual precocity   总被引:2,自引:0,他引:2  
Recently produced reference curves for various ultrasound dimensions were used to retrospectively assess 67 pelvic ultrasound scans carried out at the initial presentation in girls with sexual precocity. At presentation the group with precocious puberty had significantly increased uterine lengths and ovarian volumes compared with the normal population, and a significantly increased fundal–cervical ratio. Ovarian volume was also significantly increased in thelarche and thelarche variant. The fundal–cervical ratio was significantly increased in thelarche variant. There was considerable overlap between individuals with sexual precocity and normal subjects. The ultrasound findings that best discriminated early or precocious puberty from other forms of sexual precocity were the presence of a midline endometrial echo, and a uterine length above the 97th centile for age. An entirely normal pelvic ultrasound at presentation did not rule out the possibility of precocious puberty.  相似文献   
77.

Background

Nasopharyngeal carcinoma (NPC) and other head and neck cancer (HNCA) types show a great epidemiological variation in different regions of the world. NPC has multifactorial etiology and many interacting risk factors are involved in NPC development mainly Epstein Barr virus (EBV). There is a need to scrutinize the complicated network of risk factors affecting NPC and how far they are different from that of other HNCA types.

Methods

122 HNCA patients and 100 control subjects were studied in the region of the Middle East. Three types of HNCA were involved in our study, NPC, carcinoma of larynx (CL), and hypopharyngeal carcinoma (HPC). The risk factors studied were the level of EBV serum IgG and IgA antibodies measured by ELISA, age, sex, smoking, alcohol intake, histology, and family history of the disease.

Results

EBV serum level of IgG and IgA antibodies was higher in NPC than CL, HPC, and control groups (p < 0.01). NPC was associated with lymphoepithelioma (LE) tumors, males, regular alcohol intake, and regular smoking while CL and HPC were not (p < 0.05). CL and HPC were associated with SCC tumors (p < 0.05). Furthermore, NPC, unlike CL and HPC groups, was not affected by the positive family history of HNCA (p > 0.05). The serum levels of EBV IgG and IgA antibodies were higher in LE tumors, regular smokers, younger patients, and negative family history groups of NPC patients than SCC tumors, non-regular smokers, older patients and positive family history groups respectively (p < 0.05) while this was not found in the regular alcoholics (p > 0.05).

Conclusion

It was concluded that risk factors of NPC deviate much from that of other HNCA. EBV, smoking, alcohol intake, LE tumors, male patient, and age > 54 years were hot risk factors of NPC while SCC and positive family history of the disease were not. Earlier incidence, smoking, LE tumors, and negative family history of the disease in NPC patients were associated much clearly with EBV. It is proposed that determining the correct risk factors of NPC is vital in assigning the correct risk groups of NPC which helps the early detection and screening of NPC.  相似文献   
78.
Sphingosine-1-phosphate (S1P), produced by sphingosine kinase 1 (SphK1) or kinase 2 (SphK2), mediates biological effects through intracellular and/or extracellular mechanisms. Here we determined a role for these kinases in kidney injury of wild-type mice following ischemia-reperfusion. SphK1 but not SphK2 mRNA expression and activity increased in the kidney following injury relative to sham-operated animals. Although SphK1(-/-) mice had no alteration in renal function following injury, mice with a disrupted SphK2 gene (SphK2(tr/tr)) had histological damage and impaired function. The immune-modulating pro-drug, FTY720, an S1P agonist failed to provide protection in SphK2(tr/tr) mice. Injured kidneys of these mice showed increased neutrophil infiltration and neutrophil chemokine expression along with a 3- to 5-fold increase in expression of the G-protein-coupled receptor S1P(3) compared to heterozygous SphK2(+/tr) mice. Kidney function and reduced vascular permeability were preserved in S1P(3)(-/-) compared to S1P(3)(+/-) mice after ischemia-reperfusion injury, suggesting increased S1P(3) mRNA may play a role in the injury of SphK2(tr/tr) mice. Our study suggests that constitutive expression of SphK2 may contribute to reduced ischemia-reperfusion injury of the kidney, and its absence may enhance injury due to increased neutrophil infiltration and S1P(3) activation. We also confirm that SphK2 is necessary to mediate the protective effects of FTY720.  相似文献   
79.
The incidence of transient hypogammaglobulinaemia of infancy (THI) detected in a major paediatric centre over a 10 year period was examined. A total of 2468 subjects less than 2 years of age had an IgG measurement taken between July 1979 and March 1990. Subjects with known immunodeficiencies were excluded. Fifteen patients were classified as having THI with an initial IgG level less than the fifth centile followed by a second measurement within the normal range. A further 24 patients were identified as having possible THI with a single low IgG concentration. There were 60,174 live births each year in Victoria in the years 1979-88. This gives an incidence of proved THI of 23 per 10(6) births, and including proved and probable THI an incidence of 61 per 10(6) live births. Of those patients with proved THI 12/15 had symptoms of either atopic disease or food allergy/intolerance and three had gastrointestinal symptoms without any evidence of atopic disease. At presentation 12/15 (80%) were IgA deficient and 9/15 had IgM concentrations less than the 20th centile for age. It is suggested that in view of the preponderance of atopic and food intolerant patients that subclinical protein loss from the bowel due to allergic inflammation may be a contributing factor to the development of THI in some patients.  相似文献   
80.

Background  

Uganda began to implement the prevention of mother-to-child transmission (PMTCT) of HIV programme in 2000, and by the end of 2003 it had expanded to cover 38 of the 56 districts including Mbale District. However, reports from Mbale Hospital showed that less than 10% of pregnant women accepted antenatal HIV testing. We therefore conducted a study to determine the proportion of pregnant women who tested for HIV and the gaps and barriers in PMTCT implementation.  相似文献   
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