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41.
Summary Type 2 (non-insulin-dependent) diabetes is associated with the deposition of islet amyloid. The major formative peptide, islet amyloid polypeptide, has recently been characterised and an abnormality of the structure or expression of this gene is a possible candidate for the inherited component of Type 2 diabetes. A restriction fragment length polymorphism of the gene has been identified with Pvu II. To study the relationship between the islet amyloid polypeptide gene and Type 2 diabetes, two distinct genetic approaches have been undertaken. Firstly, non-linkage has been demonstrated in four pedigrees, with four normoglycaemic first degree relatives having an allele associated with diabetes in other family members, and one affected relative not having the putatively associated allele. The LOD score taking age-related penetrance into account was –1.68, making linkage unlikely (p=0.02). Secondly, in a population-based restriction fragment length polymorphism survey, no linkage disequilibrium of the alleles was found between a population of unrelated Caucasian subjects with Type 2 diabetes and a normal population. A mutation in or near the islet amyloid polypeptide gene is thus unlikely to be a common cause of Type 2 diabetes.  相似文献   
42.
We report the case of a lady with multiple presentations and admissions with fever. The eventual diagnosis was made of adrenocorticosteroid deficiency.  相似文献   
43.
Patients with intracerebral haematomas (ICH) secondary to aneurysmal bleeds usually have a poor prognosis or die if treated conservatively. Younger patients with rupture of a middle cerebral artery (MCA) aneurysm and temporal haematomas have the potential to return to useful life. They should be assessed separately from other subarachnoid haemorrhage (SAH) patients and considered for emergency surgery. Seven such cases are presented, five made an acceptable recovery. The experience of other units as represented in the literature is considered.  相似文献   
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During an 18-year period a consecutive series of 6591 patients underwent primary coronary bypass grafting and 508 patients underwent reoperative bypass. The mean patient age for the reoperative group was identical to that of the primary group, 59.8 years, but the mean age at initial operation for the reoperative group was 55.2 years. Mammary grafts were done at initial operation in 59% of patients who have had one operation versus only 46% of patients who subsequently required reoperation (p less than 0.001). The overall operative mortality rate was 2.0% (134/6591) for primary coronary bypass versus 6.9% (35/508) for reoperations (p less than 0.001). Patients with a reoperative interval of 1 to 10 years had a 6.0% (18/312) mortality rate, compared with 17.6% (13/74) for those in whom the interval between operations was greater than 10 years (p less than 0.01). Ventricular arrhythmias, excessive bleeding, prolonged ventilatory support, intraaortic balloon pump insertion (all p less than 0.05), and perioperative myocardial infarction (p less than 0.001) were all more prevalent after reoperations. Including perioperative mortality, the actuarial survival rate at 5 years was 80% for reoperations versus 90% for primary operations. The corresponding figures at 10 years were 65% and 75%. The probability of undergoing reoperation within 5 and 10 years was 0.034 +/- 0.003 and 0.055 +/- 0.005, respectively. Ten years postoperatively, 36% of patients having the initial operation had recurrent angina whereas 58% of the reoperative group had significant recurrent angina. Ten years after reoperation, 30% of operative survivors were free of heart-related morbidity and mortality compared with 50% of patients having a primary operation. Univariate analysis of factors increasing the probability of reoperation include the absence of a mammary graft and younger age at operation. Patients undergoing a second bypass operation represent a substantially higher risk subgroup than patients undergoing initial operation in terms of perioperative morbidity, mortality, decreased long-term survival, and decreased relief of recurrent cardiac morbidity.  相似文献   
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In the past two decades, there has been a gradual trend to regionalization of perinatal care, categorization of hospitals and transport services for neonatal health care. The literature alludes to both beneficial and deleterious effects of neonatal transport (T) but no controls such as a matched nontransport (NT) population have been utilized to date.The major goal of this study was to evaluate the effect of neonatal transport from Level I and II high risk 2500 gm. neonates (born in NYC in one calendar year, 1979) compared to a cohort nontransported population matched for hospital of birth, weight, race, sex and risk. All transported 2500 gm. from Level I and II (n=328) were studied and a stratified random sample of the nontransported (NT) infants 2500 gm. from these same hospitals (n=2042) was used for comparison. The principle outcome variable was survival. The major conclusion of this study is that in Level I and II hospitals the transport group had a significantly increased survival in infants who were sick (Apgar <6) compared to cohorted nontransported controls. Interhospital differences in survival were noted among Level I and II but not seen in the subdivisions of (A) and (B) hospitals.Angelo Ferrara, M.D., Ph.D., is Professor, Pediatrics, NYU Medical Center, New York, N.Y.: Melvin Schwartz, M.D., was Research Professor, Environmental Medicine, NYU Medical Center, New York, N.Y.; Helen Page, R.N., M.P.A., is Quality Assurance Reviewer, Manhattan Eye, Ear, Throat Hospital, New York, N.Y.: Morton Israel, M.A., is Research Scientist, Health Resources Administration, City of N. Y., New York, N.Y.; Yucel Atakent, M.D., M.S., is Clinical Associate Professor, NYU Medical Center, New York, N.Y.; C.E. Smith, Ph.D., is President, Health Policy Analysis & Accountability Network, Inc. (HPAAN), Edgewood, New Mexico; Leon Landovitz, Ph.D., is Vice President, Management Information Systems, Healthways System Inc., Islin, N.J.Supported by NCHSR Grant #5-R018-HSO3832  相似文献   
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Forty-one patients with adrenal cortical tumors were evaluated retrospectively for the presence of histologic and non-histologic features associated with malignant behavior. The patients who survived operation were followed at least five years. The association of these features with subsequent metastasis was examined by both parametric and nonparametric statistical methods. Twelve criteria were statistically significant in predicting subsequent metastasis. The most significant of these were: clinical evidence of weight loss, broad fibrous bands traversing the tumor, a diffuse growth pattern, vascular invasion, tumor cell necrosis, and tumor mass. The tendency toward metastasis for each tumor was expressed in indices that correlated well with diagnoses made by conventional histologic means, but were more accurate in predicting subsequent clinical behavior than nonquantitative methods of evaluation.  相似文献   
50.
Group B streptococci (GBS) usually behave as commensal organisms that asymptomatically colonize the gastrointestinal and urogenital tracts of adults. However, GBS are also pathogens and the leading bacterial cause of life-threatening invasive disease in neonates. While the events leading to transmission and disease in neonates remain unclear, GBS carriage and level of colonization in the mother have been shown to be significant risk factors associated with invasive infection. Surface antigens represent ideal vaccine targets for eliciting antibodies that can act as opsonins and/or inhibit colonization and invasion. Using a genetic screen for exported proteins in GBS, we identified a gene, designated lrrG, that encodes a novel LPXTG anchored surface antigen containing leucine-rich repeat (LRR) motifs found in bacterial invasins and other members of the LRR protein family. Southern blotting showed that lrrG was present in all GBS strains tested, representing the nine serotypes, and revealed the presence of an lrrG homologue in Streptococcus pyogenes. Recombinant LrrG protein was shown in vitro to adhere to epithelial cells in a dose-dependent manner, suggesting that it may function as an adhesion factor in GBS. More importantly, immunization with recombinant LrrG elicited a strong immunoglobulin G response in CBA/ca mice and protected against lethal challenge with virulent GBS. The data presented in this report suggest that this conserved protein is a highly promising candidate antigen for use in a GBS vaccine.  相似文献   
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