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91.
Intensive control of blood glucose reduces the incidence and progression of many of the complications of type 2 diabetes. Newer insulin formulations that approach normal physiologic patterns have made it possible to achieve glycemic goals without excessive hypoglycemia.  相似文献   
92.
Bacteria that simultaneously produce multiple extended-spectrum beta-lactamases are frequently isolated. We report an Enterobacter cloacae isolate, ES24, producing four different beta-lactamases (AmpC type beta-lactamase, TEM-1, SHV-7, and a novel extended-spectrum beta-lactamase, SHV-30). Direct sequencing of bla(SHV) gene products gave a "double peak" at position 703, suggesting the presence of more than one allele. Using fluorescence resonance energy transfer real-time PCR to detect single-nucleotide polymorphisms, we were able to distinguish two different bla(SHV) genes in a single isolate. This may prove to be a useful technique in surveys of beta-lactamase production in contemporary clinical isolates.  相似文献   
93.
CD52 expression in hairy cell leukemia   总被引:2,自引:0,他引:2  
Hairy cell leukemia (HCL) is a rare chronic B-cell lymphoproliferative disorder characterized by splenomegaly, pancytopenia, and circulating atypical lymphocytes with circumferential cytoplasmic projections. Although uncommon, HCL cases refractory to standard therapy occur, and effective alternatives are limited. There is evolving literature supporting monoclonal antibody therapy in the treatment of B-cell lymphoid malignancies, including anti-CD52 (Campath-1H, alemtuzumab). We have examined nine cases of HCL and one case of HCL variant by flow cytometry for CD52 expression. All cases expressed CD52 antigen in 92-100% of the malignant cells. The demonstration of CD52 antigen expression on HCL cells provides the rationale for the use of alemtuzumab in refractory HCL.  相似文献   
94.
Hairy-cell leukaemia (HCL) is a low grade B-cell lymphoproliferative process that presents either with lymphocytosis or neutropenia/monocytopenia. It is a disease predominantly of bone marrow and spleen, although it can also involve other organs and sites. Recent advances including multi-parameter flow cytometry and the development of antibodies with high specificity for HCL have permitted precise distinction of typical HCL from other lymphoproliferative diseases that can morphologically mimic the appearance of HCL. Although there is a commonly held belief that HCL is associated with a significant increase in second neoplasms, several recent studies have not supported this notion. The development of extremely effective therapy for HCL results in a high incidence of complete remission. However, a significant percentage of patients continue to harbour minimal residual disease that can be revealed with immunohistochemical and flow cytometric studies.  相似文献   
95.
Knowledge of the amino acids that define recognition of anti-beta-lactamase antibodies is critical to the interpretation of sensitivity and specificity of these antibodies when they are used in a clinical or research setting. To this end, we mapped the epitopes of the CMY-2 and SHV-1 beta-lactamases by using the SPOT synthesis method. Eight linear epitopes in SHV-1 and seven linear epitopes in CMY-2 were identified by using anti-SHV-1 and anti-CMY-2 polyclonal antibodies, respectively. The epitopes of SHV-1 were mapped to amino acids at the Ambler positions ABL 28 to 38, 42 to 54, 88 to 100, 102 to 114, 170 to 182, 186 to 194, 202 to 210, and 276 to 288. In the epitope spanning amino acids 102 to 114, alanine and X-Scan analysis demonstrated that D104, Y105, P107, and S109 are essential residues for antibody recognition. In the epitope containing amino acids 170 to 182, N170, L173, P174, G175, and D176 were immunodominant. In CMY-2 beta-lactamase, amino acids 4 to 16, 70 to 79, 211 to 223, 274 to 286, 289 to 298, 322 to 334, and 343 to 358 of the mature enzyme defined the major linear epitopes. A detailed analysis of the recognition sites that are located in an area analogous to the omega loop of class A beta-lactamases (V211 to V223) showed that the amino acids Q215 to E219 are important in antibody binding. Incubation of CMY-2 beta-lactamase with a 10-fold molar excess of anti-CMY-2 antibody for 60 min resulted in greater than 80% inhibition of nitrocefin hydrolysis. A 10-fold molar excess of anti-SHV-1 antibody reduced the activity of SHV-1 by 69%. Analysis of the CMY-2 and SHV-1 structures suggest that this reduction of hydrolytic activity may be due in part to the direct binding of antibodies to the omega loop, thereby hindering access of substrate to the active site.  相似文献   
96.
97.
Palliation of esophageal malignancy with photodynamic therapy   总被引:3,自引:0,他引:3  
Sixteen patients with esophageal malignancies received photodynamic therapy after 3 mg of hematoporphyrin derivative (Photofrin I) or 2 mg of Photofrin II per kilogram of body weight was injected intravenously two to six days prior to treatment. A tunable dye argon laser system delivered 630 nm light through quartz fibers passed through the biopsy channel of a gastroscope. All patients obtained improvement in swallowing, usually from total obstruction or clear liquids only to a regular diet within three weeks and with new techniques, at least liquids within three days of treatment. Karnofsky Performance Status (KPS) and esophageal grades were measured before treatment, 1 month following treatment, and periodically until death. Ten patients died an average of 3.7 months after initial treatment (range, 0.6 to 19 months). Six patients are alive at 11, 10, 5, 2.5, 2 months, and 1 month after treatment. The median survival of 12 patients treated more than 6 months ago was 6.5 months and of 9 patients with an initial KPS higher than 30, 8.1 months.  相似文献   
98.
Insulin and insulin-like growth factors (IGFs) belong to the most biologically characterized family of peptides involved in metabolism, growth and development. The cellular responses to the IGFs are mediated primarily by the IGF-I receptor. The IGF-I receptor is a member of the family of tyrosine kinase growth factor receptors, and is highly homologous (70%) to the insulin receptor, especially in the tyrosine kinase domain (84%) ADDIN. Upon ligand binding to the extracellular region, the intrinsic tyrosine kinase domain of the receptor is activated. In the past it was believed that insulin activates primarily metabolic processes while IGFs promote cell growth and differentiation. However, in the last two decades many animal models of IGFI deficiency and excess revealed the importance of IGF-I in carbohydrate and lipid metabolism and now it is clear that these peptide hormones together with growth hormone (GH) work in a coordinate and interdependent manner. In the circulation, IGFs are bound in a binary complex with a family of high affinity IGF-binding proteins (IGFBPs) ADDIN. However, most of the circulating IGF-I associates with a high molecular weight complex approximately 150 KDa consisting of IGFBP-3 and the acid labile subunit (ALS) ADDIN. Once the ternary complex dissociates, the binary complexes of IGFBP-IGFs are removed from the circulation and by crossing the endothelium to reach the target tissues and to interact with cell surface receptors. In the present review we will summarize the role of GH and IGF in somatic growth and focus on the metabolic effects of IGF-I deficiency as assessed in various mouse models.  相似文献   
99.
Outcome of pregnancy in a woman with an increased body mass index   总被引:4,自引:4,他引:0  
OBJECTIVE: To show the increased risk of adverse outcomes in labour and fetomaternal morbidity in obese women (BMI > 30). DESIGN: A population-based observational study. SETTING: University Hospital of Wales. The study sample was drawn from the Cardiff Births Survey, a population-based database comprising of a total of 60,167 deliveries in the South Glamorgan area between 1990 and 1999. Population Primigravid women with a singleton uncomplicated pregnancy with cephalic presentation of 37 or more weeks of gestation with accurate information regarding height and weight recorded at the booking visit (measured by the midwives) were included in the study. METHODS: Comparisons were made between women with a body mass index of 20-30 and those with more than 30. SPSS version 10 was used for statistical analysis. Student's t test, chi(2) and Fisher's exact tests were used wherever appropriate. MAIN OUTCOME MEASURES: Labour outcomes assessed were risk of postdates, induction of labour, mode of delivery, failed instrumental delivery, macrosomia and shoulder dystocia. Maternal adverse outcomes assessed were postpartum haemorrhage, blood transfusion, uterine and wound infection, urinary tract infection, evacuation of uterus, thromboembolism and third- or fourth-degree perineal tears. Fetal wellbeing was assessed using Apgar <7 at 5 minutes, trauma and asphyxia, cord pH < 7.2, babies requiring neonatal ward admissions, tube feeding and incubator. RESULTS: We report an increased risk [quoted as odds ratio (OR) and confidence intervals CI)] of postdates, 1.4 (1.2-1.7); induction of labour, 1.6 (1.3-1.9); caesarean section, 1.6 (1.4-2); macrosomia, 2.1 (1.6-2.6); shoulder dystocia, 2.9 (1.4-5.8); failed instrumental delivery, 1.75 (1.1-2.9); increased maternal complications such as blood loss of more than 500 mL, 1.5 (1.2-1.8); urinary tract infections, 1.9 (1.1-3.4); and increased neonatal admissions with complications such as neonatal trauma, feeding difficulties and incubator requirement. CONCLUSION: Obese women appear to be at risk of intrapartum and postpartum complications. Induction of labour appears to be the starting point in the cascade of events. They should be considered as high risk and counselled accordingly.  相似文献   
100.
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