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81.
Previously, we identified the glycoprotein gO gene, UL74, as a hypervariable locus in the human cytomegalovirus (HCMV) genome [Virology 293 (2002) 281]. Here, we analyze gO from 50 isolates from congenitally infected newborns, transplant recipients, and HIV/AIDS patients from Italy, Australia, and UK. These are compared to four gO groups described from USA transplantation patients [J. Virol. 76 (2002) 10841]. Phylogenetic analyses identified seven genotypes. Divergence between genotypes was up to 55% and within 3%. Discrete linkage was shown between seven hypervariable gO and gN genotypes, but not with gB. This suggests interactions, while gN and gO are known to form complexes with distinct conserved glycoproteins gM, gH/gL, respectively, both are involved in fusogenic entry and exit. Codon-based maximum likelihood models showed evidence for sites of positive selection. Further analyses of disease relationships should take into account these newly defined gO/gN groups.  相似文献   
82.
Zusammenfassung Ein Radioimmunoassay für Angiotensin I und seine Anwendung für die Messung der Reninkonzentration im Plasma werden beschrieben. Die zur Herstellung von Angiotensinantikörpern und radioaktiv markiertem Angiotensin sowie zur Trennung von gebundenem und freiem Hormon benutzten Verfahren werden mitgeteilt. Die Empfindlichkeit der Methode erlaubt den Nachweis von zwanzig Pikogramm Angiotensin I.Zur Messung der Reninkonzentration wurde substratfreies Plasma mit Schafsubstrat im Überschuß versetzt und in Anwesenheit von Inhibitoren von converting enzyme und Angiotensinasen bei 37°C inkubiert. Das gebildete Angiotensin wurde in 20 µl des proteinfreien Inkubationsgemisches bestimmt. Die initiale Geschwindigkeit der Angiotensinbildung wurde zur Berechnung der Reninkonzentration herangezogen. Als eine Einheit wurde die Reninmenge definiert, die ein Nanogramm Angiotensin I pro Stunde Inkubation bildet.Normalwerte unter kontrollierter natriumreicher und natriumarmer Diät wurden ermittelt.Die Empfindlichkeit der Methode erlaubt die Messung der Reninkonzentration im Plasma von Patienten mit primärem Aldosteronismus.Mit Unterstützung der Deutschen Forschungsgemeinschaft.  相似文献   
83.
84.
To determine whether the pharmacokinetics and pharmacodynamics of beta-blockade differ among racial groups, we gave 10 men of Chinese descent and 10 American white men 10, 20, 40, and 80 mg of propranolol every eight hours; the dosages were given in random order, and each dose was given for one day. The degree of beta-blockade was measured as the reduction in the heart rate and blood pressure in the supine and upright positions and during treadmill exercise testing. The Chinese subjects had at least a twofold greater sensitivity to the beta-blocking effects of propranolol than the white subjects, as indicated by the mean (+/- SEM) plasma concentrations producing a 20 percent reduction in the heart rate in both the supine position (197 +/- 31 vs. 536 +/- 58 nmol per liter; P less than 0.05) and the upright position (131 +/- 27 vs. 343 +/- 39 nmol per liter; P less than 0.05) and after exercise testing (96 +/- 12 vs. 185 +/- 23 nmol per liter; P less than 0.05). In addition, the Chinese subjects had much greater sensitivity to the hypotensive effects of propranolol, as shown by the concentrations that reduced blood pressure by 10 percent in the supine position (73 +/- 5 vs. 748 +/- 7 nmol per liter; P less than 0.01) and in the upright position (89 +/- 5 vs. 401 +/- 6 nmol per liter; P less than 0.01). No difference in beta-receptor density or affinity of lymphocytes was found between the groups. The Chinese group had a 45 percent higher free fraction of propranolol in plasma, which may have contributed to the increased drug effect but cannot explain it entirely. This group metabolized propranolol more rapidly than the white group, which resulted in a 76 percent higher clearance of an oral dose (3740 +/- 737 vs. 2125 +/- 214 ml per minute; P less than 0.05) because of increased metabolism through multiple metabolic pathways. We conclude that Chinese men have greater sensitivity than white men to the effects of propranolol on heart rate and blood pressure. Decreased protein binding may be responsible in part, but most of the effect remains to be explained.  相似文献   
85.
A novel mutation was identified in two unrelated patients with medium-chain acyl-CoA dehydrogenase deficiency. First, a 19-year-old Caucasian female presented with a devastating illness, resulting in sudden death in adulthood which is unusual. The second patient, now a 3.5-year-old male, presented at 17 months of age with a hypoglycemic seizure and dehydration. Sequence analysis revealed a novel mutation G617T in exon 8 resulting in an arginine to leucine substitution at codon 206 (R206L). Both patients were compound heterozygous for this G617T and the common mutation A985G.  相似文献   
86.
We report a primary uterine sarcoma with classic histologic, immunohistochemical, and ultrastructural features of a malignant extrarenal rhabdoid tumor (MERT). It arose in a 71-year-old woman who presented with postmenopausal bleeding, ascites, and a right pelvic mass. Malignant cells with rhabdoid morphology were identified by cytologic examination of the peritoneal fluid. Exploratory laparotomy revealed a 10-cm right adnexal mass and disseminated peritoneal tumor. Pathologic study showed diffuse expansion of the endometrial stroma by rhabdoid-like cells with transmural infiltration of the myometrium and extensive involvement of uterine serosa and right ovary by tumor. Neoplastic cells were immunoreactive for vimentin, cytokeratin, and epithelial membrane antigen, and cytoplasmic whorls of intermediate filaments were observed by electron microscopy. Fluorescence in situ hybridization (FISH) studies with chromosome 22-specific probes showed no loss of the INI1 gene, and no coding sequence mutation was identified.  相似文献   
87.
88.
Current interest in determining the possible protective role of antibodies against group B streptococcal disease prompted this study of the feasibility of using a radioimmunoassay to measure type-specific immunity in humans. The radioimmunoassay was standardized as a quantitative test for antibodies against the carbohydrate (CHO) antigens of all five group B types. The data showed that the CHO antigens extracted by a cold trichloroacetic acid-sonification method measure more antibodies than do the corresponding CHO antigens extracted by hot hydrochloric acid; that the Ia CHOs extracted from two different types, Ia and Ic, measure the same quantity of Ia antibodies; and that human sera contain antibodies reactive with all five type-specific CHOs. No evidence of "protective" antibody was found in the serum samples studied, although there was evidence of and antibody response in adults to prolonged colonization by group B streptococci. The wide ranges of antibody concentration in a serum bank collection, the broad reactivity of all human sera tested, and the mixed populations of antibodies in human sera that react with different determinants on the same type-specific CHO antigen (type III) indicate that further studies must be done to better define normal and susceptible populations and to determine antigenic components important in protection.  相似文献   
89.
BACKGROUND: In our clinic we routinely patch test patients referred from occupational health for the investigation of latex contact urticaria. We also undertake both patch and prick testing (where indicated) in patients referred with persistent dermatitis/eczema. If investigation of allergic skin disease is undertaken by a non-dermatologist, it is unlikely that patch testing will be performed. OBJECTIVE: To carry out a retrospective analysis of patients who had been prick tested to establish whether an incomplete diagnosis would have been reached if patch testing had been omitted. METHODS: Details of patients who had attended for patch testing between July 2004 and December 2005 were analysed. Patients who had had prick tests and patch testing were identified. The outcomes of prick tests and patch testing were documented together with the clinical relevance. RESULTS: Three hundred and thirty out of 1060 patients referred to the clinic were prick tested. 54.2% patients were referred from dermatologists. 26.6% were referred from occupational health, 68 patients had positive reactions on prick testing of whom 36 had positive patch tests (52.9%), which were of current relevance in 27 patients (39.7%). Nine out of 106 health workers referred to exclude latex contact urticaria had positive prick tests to latex. Fifty of these patients demonstrated delayed-type hypersensitivity with nickel, cobalt, rubber and its additives being the most common allergens found. Of the 262 patients who had negative prick tests, 121 had positive patch tests (46.1%) of current relevance to patient history in 92 subjects (35.1%). While none of the six patients referred for investigation of reaction to local anaesthetics had a positive prick test, one was allergic to local anaesthetic on patch testing. CONCLUSION: Omission of patch testing from the investigation of allergic skin disease, even when contact urticaria may be the sole suspected diagnosis, would result in the frequent missed diagnosis of contact allergy. We recommend that patients with suspected allergic skin disease are investigated in an environment where investigation of both immediate- and delayed-type hypersensitivity can be undertaken. In particular, patients with atopic eczema, suspected latex rubber allergy, hand dermatitis (particularly occupational) and drug reactions should be targeted to receive both investigations.  相似文献   
90.
A questionnaire on general practitioners' use of community psychiatric nursing services was sent to a random sample of 100 general practitioners in two contrasting areas, Croydon and Cambridgeshire. General adult services were widely available though used less often by Cambridgeshire general practitioners than Croyden doctors. Apart from services for the elderly, specialist services were uncommon. Over a third of doctors reported that their adult services were based in a psychiatric hospital. Less than a quarter of general practitioners had access to primary care based nurses. The pattern of responses demonstrates the wide variety of ways in which general practitioners relate to community psychiatric nurses, even where the psychiatric nursing services are long-established. There remains a need for more consistent and coherent policies about the ways in which community psychiatric nurses are employed in primary care.  相似文献   
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