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81.
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   
82.
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   
83.
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   
84.
ObjectiveTo screen for Escherichia coli (E. coli) resistant to tetracycline, followed by identification of tet efflux genes by polymerase chain reaction (PCR). In addition, detection of tetracycline residues in chicken livers and kidneys were conducted using high performance liquid chromatography-tandem quadrupole mass spectrometry (HPLC-MS-MS).MethodsStrains of E. coli were isolated from samples of chicken colon and screened for tetracycline resistance. Tetracycline genes conferring resistance (Tcr) were detected by polymerase chain reaction (PCR). Most of the isolates were resistant to tetracycline (97.9%).ResultsPCR analysis indicated that Tcr E. coli R-plasmids contained tet(A), tet(B) and a combination of both efflux genes. None of the isolates contained other efflux tet genes tet (C, D, E and Y). High performance liquid chromatography-tandem quadrupole mass spectrometry (HPLC-MS-MS), a sensitive technique, was used to detect residues of chlortetracycline (CTC), oxytetracycline (OTC), doxycycline (DC) in chicken livers and kidneys. The samples containing tetracycline residues were at 0.13-0.65 pg/μL levels.ConclusionsTetracycline and other antibiotics are commonly used in the poultry and meat production industry for prevention of microbial infections. Multiple antibiotic resistant bacteria in Oman have increased to alarming levels, threatening public health, domestic and may have adverse effect on environment.  相似文献   
85.
Ten years have now passed since the College of Medicine of the University of Malawi was opened. The College''s Curriculum is firmly based on community needs. We describe the genesis and implementation of the curriculum of the College of Medicine and how it has persisted over the past ten years. The challenges that have so far been met are outlined.  相似文献   
86.
A cross sectional study was done between October 1999 and February 2000 to determine antimicrobial susceptibility patterns of consecutive bacterial isolates of 102 clinical samples among surgical in-patients at Lilongwe Central Hospital (LCH), Malawi. Antimicrobial susceptibility was determined using comparative disc diffusion techniques. 83 (81.4%) samples were culture positive for bacterial growth while 19 (18.6%) grew nothing. Of the 93 culture positive specimens, Staphylococcus aureus was the predominant organism 43(51.8%) followed by Proteus species 8(9.6%) and E. coli 7(8.4%). Overall, 98.6% of all isolates tested against ciprofloxacin were susceptible, and against gentamicin and flucloxacin were 84.8% and 66.7% respectively. 59.3% of isolates tested against chloramphenicol were resistant. We recommend a review on the use of chloramphenicol as first-line antimicrobial therapy among surgical in-patients at Lilongwe Central Hospital. We also recommend restricted use of antimicrobials so as to minimise development of drug resistance. Periodic susceptibility studies are necessary to guide judicious use of antibiotics.  相似文献   
87.

Introduction

Reconstruction of large abdominal wall defects not amenable to primary closure remains a challenging problem. These defects result from trauma, previous surgery, infection and tumour resection. The primary objectives of abdominal wall reconstructions are to protect abdominal contents and provide functional support. The abdominal wall reconstruction aims at providing basic component parts, i.e. skin, soft tissue and fascia. For large soft tissue defects, pedicled or free flap closure can be used. In clean wounds, fascial replacement is accomplished with synthetic mesh provided there is adequate soft tissue coverage.

Methods

We treated a total of 20 consecutive patients with complex abdominal wall defects utilizing various reconstructive procedures. There were 15 males (75%) and 5 females (25%). The aetiology included dehiscence of laparotomy wounds in eight (40%), following ablative surgery for malignant tumours in seven (35%), trauma in three (15%) and congenital defects in two (10%) cases. The reconstructive procedures consisted of onlay prolene mesh in seven (35%), Gore-Tex (PTFE) dual mesh both as inlay and onlay in five (25%), facial partition release technique in three (15%), inlay prolene mesh covered with omentum and split skin graft in two (10%), inlay prolene mesh covered with expanded skin in two (10%), and Gore-Tex dual mesh covered with latissimus dorsi myocutaneous flap in one (5%) case. Postoperatively none developed mesh infection or extrusion. Three patients with malignant aetiology received postoperative radiotherapy. During follow up, one patient developed ventral hernia cephalad to the repair and one died due to recurrence of abdominal wall malignancy.

Conclusion

The reconstruction of an abdominal wall defect requires a comprehensive plan of preoperative and post operative care of the patient and aims toward restoration of abdominal structural integrity by a variety of procedures. The use of new biomaterials and tissue expanders provides reliable and durable abdominal wall closure along with good aesthetic results.Key Words: Abdominal wall defect, Mesh repair, Abdominal wall reconstruction  相似文献   
88.
Hong J  Samudio I  Liu S  Abdelrahim M  Safe S 《Endocrinology》2004,145(12):5774-5785
1,1-Bis(3'-indolyl)-1-(p-trifluoromethylphenyl)methane (DIM-C-pPhCF3) and troglitazone activate peroxisome proliferator-activated receptor gamma (PPARgamma) in Panc-28 pancreatic cancer cells and also inhibit cell proliferation. DIM-C-pPhCF3 was more active than troglitazone and was used as a model to investigate the mechanism of PPARgamma-dependent inhibition of Panc-28 cell growth. DIM-C-pPhCF3 significantly inhibited G0/G1-->S phase progression, as determined by FACS analysis, and this was associated with decreased retinoblastoma protein phosphorylation and increased p21 protein and mRNA expression, but no change in p27 or cyclin D1. PPARgamma antagonists blocked DIM-C-pPhCF3-induced growth inhibition and induction of p21 protein, and similar inhibitory effects were observed in Panc-28 cells transfected with a construct (pWWP) containing a -2325 to +8 p21 promoter insert. Deletion analysis of the p21 promoter indicated that PPARgamma-dependent activation of p21 promoter constructs by DIM-C-pPhCF3 required GC-rich sites 3 and 4 in the proximal region (-124 to -60) of the p21 promoter. The results of RNA interference and protein expression/DNA binding assays suggest that DIM-C-pPhCF3 induced p21 expression through a novel mechanism that involves PPARgamma interactions with both Sp1 and Sp4 proteins bound to the proximal GC-rich region of the p21 promoter.  相似文献   
89.
Twenty patients with poor prognosis B-cell chronic lymphocytic leukemia (B-CLL) underwent uniform high-dose chemoradiotherapy followed by rescue with multiple monoclonal antibody-purged autologous bone marrow (BM) (12 patients) or T-cell-depleted allogeneic BM from HLA-identical siblings (8 patients) in a pilot study to assess the feasibility of BM transplantation (BMT) in this disease. All had poor prognosis disease by either staging, BM pattern, tumor doubling time criteria, or cytogenetics. All patients achieved remission criteria (defined as < or = 2 adenopathy, absence of splenomegaly, < or = 20% of the intertrabecular space involved on BM biopsy) before BMT. Despite the use of fludarabine, a median of three treatment regimens were required to achieve BMT eligibility. After BMT, all patients achieved complete hematologic engraftment. Toxicities were not significantly different between autologous versus allogeneic BMT. Two toxic deaths were observed. Of 19 evaluable patients, 17 clinical complete clinical remissions (89%) were observed, with 2 patients (1 allogeneic and 1 autologous) exhibiting persistent BM disease. Complete clinical remissions were documented at the phenotypic and molecular level for the majority of patients in whom dual fluorescence for CD5 and CD20 (15 of 15; 100%) and Ig gene rearrangements (11 of 14; 79%) were performed. Although long-term follow-up is needed to assess any potential impact on the disease-free and overall survival of these patients, this study shows the feasibility of using high-dose chemoradiotherapy and BMT in patients with poor prognosis B-CLL.  相似文献   
90.
Immunologic heterogeneity of diffuse large cell lymphoma   总被引:2,自引:0,他引:2  
The cellular lineage of 57 diffuse large-cell lymphomas (DLCLs) was determined using a panel of monoclonal antibodies directed against lineage-restricted and -associated T, B, and monocyte antigens. The majority (82%) were of B cell lineage as determined by the expression of sig and/or B1, with the remaining 16% being of T cell lineage and 2%, of monocyte-myeloid lineage. By the expression of other B cell- restricted and -associated antigens, two major and two minor subgroups could be identified. These subgroups expressed the following phenotypes: (1) B1+B4+sIG+B2- (51%); (2) B1+B4+sIg+B2+ (29%); (3) B1+B4+sIg-B2+ (10%); and (4) B1+B4-sIg+B2- (10)%. The morphology of transformed lymphocytes, the weak to absent expression of the early B cell antigens B2 and sIgD, and the absence of the late B cell differentiation antigens PCA-1 and PC-1 suggested that these tumors were the neoplastic counterparts of normal B cells at the mid-stages of differentiation. Further support for the notion that B-DLCLs correspond to transformed B lymphocytes was concluded from the observation that B cells could be identified in normal spleen that expressed the cell surface phenotype and morphological appearance of the majority of B- DLCLs.  相似文献   
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