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1.
2.
Dubbelman and co-workers have determined intraocular spacings and surface shapes in living eyes by means of corrected Scheimpflug images in a large number of subjects of different age at several levels of accommodation. They give relationships for key anterior segment parameters as a function of age and level of accommodation. These are used in this paper to build a schematic eye incorporating aspheric surfaces. This eye model is analysed by means of ray tracing with a technique developed for use with a common spreadsheet computer program. The Dubbelman eye model appears to be well corrected for spherical aberration. Compared with measurements on real eyes it agrees well in general, but spherical aberration is negative, while in real eyes it tends to be positive.  相似文献   
3.
In vitro experiments have indicated that in primary hyperparathyroidism (HPT) the hyperfunctioning glands have a set point error, i.e., they are not autonomous but regulate serum calcium around a hypercalcémie value. In contrast, parathyroid function is suppressed in patients with hypercalcemia of causes other than HPT (e.g., malignancy or sarcoidosis). The basal measurements of serum parathyroid hormone (PTH) levels, however, cannot, alone, separate with precision HPT from other causes of hypercalcemia.Lowering of calcium, in order to stimulate secretion of PTH, was, therefore, achieved by either infusion of Na2 EDTA (24 mg/kg per hr) for 1 hour, or intramuscular injection of 100 IU salmon calcitonin. All 35 patients with primary HPT displayed a significant increase of serum PTH concentrations, evaluated by a midregion/intact hormone assay, during the EDTA infusion, which lowered plasma ionized calcium by an average of 0.16 mmol/l. The injection with calcitonin reduced the calcium concentrations by 0.10 mmol/l after 8 hours and caused a rise in PTH in 80% of HPT patients. With both tests, the secretory response by PTH to the reduction of plasma calcium was generally evident while the patients were still hypercalcemic. In 32 patients with other causes for hypercalcemia, primarily malignancy and sarcoidosis, similar reductions of plasma ionized calcium were obtained. In contrast to the HPT patients, none of them raised their serum PTH values during the test. Thus, stimulation of PTH secretion by a moderate reduction of serum calcium considerably improves the differential diagnosis of hypercalcemia since a significant secretory response appears to be exclusive for HPT.
Resumen Experimentos in vitro han señalado que en el hiperparatiroidismo primario (HPT) las glándulas hiperfuncionantes tienen un error en su set point, o sea que no son autónomas sino que regulan el calcio sérico alrededor de un valor hipercalcémico. Por el contrario, la función paratiroidea es suprimida en pacientes con hipercalcemia de causa diferente de HPT (e.g., neoplasias malignas o sarcoidosis). Las mediciones basales de los nivelés séricos de hormona paratiroidea (PTH) de por sí no son capaces de diferenciar con precision entre el HPT y la hipercalcemia de otras causas.La disminución del nivel de calcio sérico, con el objeto de estimular secreciones de PTH, fue lograda con la infusión de Na2 EDTA (24 mg/Kg por hora) por 1 hora o la inyección i.m. de 100 UI de calcitonina de salmón.Todos los 35 pacientes con HPT primario exhibieron un aumento significativo de las concentraciones séricas de PTH, determinadas mediante la medición de la fraction media/intacta de PTH en el curso de la infusion de EDTA, la cual redujo el nivel plasmático de calcio ionizado en un promedio de 0.16 mmol/l. La inyección de calcitonina redujo las concentraciones de sérico en 0.10 mmol/l a las 8 horas y resultó en un aumento de la PTH en 80% de los pacientes con HPT. Con ambas pruebas la respuesta secretoria de PTH a la reducción del calcio plasmático generalmente apareció evidente aún mientras los pacientes se hallaban hipercalcémicos.En 32 pacientes con hipercalcemia de causa diferente, se lograron reducciones similares de la concentration plasmática del calcio ionizado. Por el contrario de lo observado en los patientes con HPT, ninguno demostró elevatión de sus niveles séricos de PTH en el curso de la prueba. Por consiguiente, el estímulo de la secretión de PTH mediante la reductión moderada de calcio sérico incrementa considerablemente la (ie501-01)acidad de establecer el diagnóstico diferencial de la hipercalcemia, puesto que una significativa respuesta secretoria parece ser caracteristíca exclusiva del HPT.

Résumé L'expérimentation in vitro a démontré que dans l'hyperparathyroïdisme (HPT), les glandes hyperactives ont un point mort erroné, c'est-à-dire qu'elles ne sont pas autonomes mais règlent la calcémie autour d'une valeur de référence déjà hypercalcémique. En revanche, la fonction parathyroîde est déprimée chez le patient dont l'hypercalcémie est due à une cause autre que l'HPT (cancer ou sarcoïdose par exemple). La mesure des niveaux de base de la parathormone (PTH), cependant, ne permet pas de distinguer l'hypercalcémie de l'HPT des autres causes d'hypercalcémie avec précision.Dans le but de stimuler la sécrétion de PTH, la calcémie était abaissée soit en perfusant les patients avec une solution de Na2 EDTA (24 mg/Kg) pendant une heure, soit par une injection intramusculaire de 100 U de calcitonine de saumon.Trente-cinq patients ayant un HPT primitif présentaient une augmentation significative des concentrations en PTH sérique, évaluée par l'étude immunologique de la portion moyenne intacte, pendant la perfusion d'EDTA. La portion de calcium plasmatique ionisée a été abaissée en moyenne de 0.16 mmol/l. L'injection de calcitonine a réduit la concentration en calcium par 0.10 mmol/l après huit heures et a provoqué une augmentation en PTH chez 80% des patients à HPT. Quel que soit le test, la réponse de PTH à la réduction de calcium plasmatique était généralement évidente alors que le patient était toujours hypercalcémique.Chez 32 autres patients ayant pour cause d'hypercalcémie cancer ou sarcoïdose, des réductions similaires en calcium plasmatique ionisé ont été obtenues. Aucun malade, contrairement aux patients HPT, n'a vu son niveau de PTH monter pendant le test. Ainsi, la stimulation de sécrétion de PTH par une réduction modérée de calcium sérique améliore considérablement le diagnostic différentiel des hypercalcémies puisque la réponse sécrétoire significative paraît être le fait exclusif des HPT.


Presented at the International Association of Endocrine Surgeons in Sydney, Australia, September, 1987.

Supported by the Swedish Medical Research Council.  相似文献   
4.
Proportions of T cells and T cell subsets, as identified by their Fc receptors (FcR) for IgM and IgG (Tmu and T gamma), were determined in the peripheral blood lymphocyte (PBL) and cerebrospinal fluid (CSF) lymphocyte populations in patients with multiple sclerosis (MS). On average, MS patients had 79% total T cells (62% of which were T gamma, 66% Tmu) in CSF lymphocytes compared to 66% total T cells (30% T gamma, 63% Tmu) in PBL. Normal age- and sex-matched controls PBL had 74% total T cells (20% T gamma, 54% Tmu). By direct observation using an indirect immunofluorescence assay, 41% of the CSF T gamma cells in MS patients bore receptors for IgM; these cells were designated T gamma mu and, according to the double-marker analysis, did not seem to correlate with disease stage. In MS PBL, 20% of T gamma cells were T gamma mu compared to 9% in the control PBL T gamma population. Thus, MS patients had a higher proportion of total T cells, T gamma cells and T gamma mu cells in their CSF than in their peripheral blood and than those populations found in normal control blood. The significance of this T gamma mu population for the continuing disease state in MS is discussed.  相似文献   
5.
Cerebrospinal fluid (CSF) and serum from 19 patients with mumps meningitis and 19 patients with meningitis of other etiology were investigated on two or more occasions for at least 1 month after onset. Intrathecal synthesis of immunoglobulin (Ig) G was found in 55%, of IgA in 26%, and of IgM in 24% of the patients. Oligoclonal Ig was demonstrable by agarose gel electrophoresis in 37% of the patients, mostly already during the first week after onset, and could persist for years. Mumps virus antibody synthesis within the central nervous system occurred in 37% of the mumps meningitis patients. The inflammatory reaction within the central nervous system as reflected by mononuclear pleocytosis, Ig synthesis, and oligoclonal Ig was not correlated to the clinical course. The blood-brain barrier was evaluated by determination of the CSF total protein, CSF/serum albumin ratio, and CSF/serum alpha2-macroglobulin ratio. A significant correlation was found among these three parameters. Persistence of the elevated CSF/serum albumin ratio seems to influence prognosis, and this parameter is recommended for evaluation of the blood-brain barrier function.  相似文献   
6.
"Natural" hemagglutinin titers against a panel of fixed erythrocyte antigens were determined for groups of Minnesota miniature swine reared conventionally, in a specific pathogen-free facility, and in germfree isolators. Sera were assayed for hemagglutination (HA) titers by the microtiter method against 12 species of erythrocytes stabilized by treatment with pyruvic aldehyde and formaldehyde. These erythrocytes were stable for up to 2 years and gave slightly enhanced HA titers as compared to fresh, unfixed erythrocytes. Of the sera from conventional swine tested, the highest "natural" HA titers were directed towards rabbit, cat, swine dog, and burro erythrocytes (greater than 1:1,000), intermediate titers were detected against human A, B, and O, and sheep, pig, and chicken erythrocytes (1:64 to 1:1,000), whereas the lowest titers were found against ox and goat erythrocytes (less than 1:8). Titers obtained with sera from specific pathogen-free swine were 2- to 16-fold lower than those of conventional swine, but were of a similar distribution with regard to the species of erythrocyte tested. Germfree swine sera uniformly exhibited HA titers less than 1:4 against all species of erythrocytes. The majority of these hemagglutinins were immunoglobulin M class but there were some agglutinins of immunoglobulin A class and a slight amount of immunoglobulin G class. Specificity of these agglutinins was examined by absorption tests. The results are consistent with the hypothesis that natural hemagglutinins develop due to dietary or microbial antigenic stimulation, or both.  相似文献   
7.
Summary Experimental infection with HVJ (haemagglutinating virus of Japan—the Sendai strain of parainfluenza 1 virus) in mice was studied. Aerosol infection of newborn mice with the wild-type virus (HVJ-W) retarded the development of body weight and killed the animals within a few weeks. Large amounts of virus were isolated from both the lungs and the nasal turbinates of infected mice. In contrast, newborn mice exposed by inhalation to a temperature-sensitive(ts) mutant (HVJ-pB) derived from an HVJ carrier culture showed no clinical signs and grew equally well as mock-infected animals. No infectious virus could be recovered from the lungs although thets mutant grew to moderate titre in the nasal turbinates.The prior inoculation of newborn mice with thets mutant virus induced a state of significant resistance to subsequent challenge with the virulent wild-type virus.No replication of challenge virus in both lungs and nasal turbinates could be detected and the animals were protected a lethal infection. It is suggested that an avirulent temperature-sensitive mutant which has lost the capacity to replicate in the lower respiratory tract but is still capable of multiplying in the nasal turbinates may be a promising candidate for use in live vaccines especially against the infectious disease of the lower respiratory tract.With 2 Figures  相似文献   
8.
Togashi  T.  Örvell  C.  Vartdal  F.  Norrby  E. 《Archives of virology》1981,67(2):149-157
Summary Mouse hybridoma cell lines were produced by fusion of P3 × 63 Ag8 myeloma cells with spleen cells from BALB/c mice immunized with purified measles virions. About 60 per cent of single cell colonies in wells were found to produce measles antibodies as determined by a radioimmune assay. Selected measles antibody producing hybridoma cell lines were passaged intraperitoneally in mice and ascites fluids were collected. This material contained 20–200 times higher antibody titers than unconcentrated medium from hybridoma cell lines propagated in tissue culture. The ascites fluid antibody products of 23 hybridoma cell lines were characterized by different measles serological tests. Seventeen lines produced high titers of hemagglutination inhibiting (HI) and hemolysis-inhibition (HLI) antibodies. One hybridoma cell line produced Ig with low HI but high HLI activity and the remaining 5 hybridoma cell line products only carried HLI activity. Unexpectedly it was found in radioimmune precipitation assays that all hybridomas studied, including those showing HLI but no HI antibody activity, gave a selective precipitation of the 79K measles hemagglutinin polypeptide. Radioimmune precipitation assays with sera from immunized animals showed that they contained high titers of antibodies precipitating the 79 K polypeptide but in addition also somewhat lower titers of antibodies precipitating the 60 K nucleoprotein, 40 K fusion and 36 K matrix polypeptides. Homogeneous Ig products carrying measles antibody activity were demonstrated by imprint immunoelectrophoresis of ascites materials.With 2 Figures  相似文献   
9.
Two partially overlapping 19 and 22 amino acids long peptides representing a highly immunogenic site of the transmembranous glycoprotein (gp41) of human immunodeficiency virus (HIV) were used as antigen in ELISA tests. The results of antibody determination with this assay were compared with those of three or more conventional ELISAs and Western blot (WB) tests and radioimmunoprecipitation assay. Twenty-six sera from patients with AIDS or LAS and from asymptomatic carriers of HIV infection all showed a pronounced reaction in the peptide ELISA as well as positive results with other tests. In contrast, 27 sera from laboratory workers and blood donors were negative by all tests. A group of 39 blood donor sera, which had shown false positive or ambiguous results in the ELISAs and sometimes in WB tests employed for confirmation, also were negative in all cases with the peptide ELISA. Consecutive samples collected from individuals with primary HIV infection were also analyzed. In 6 out of 9 cases, the peptide ELISA revealed an antibody response within one month after onset of clinical symptoms and sensitivity for antibody detection equaled that of other ELISA tests. Eight sera from five West African persons infected with HIV-related viruses did not react in the peptide ELISA, reflecting differences in properties of the envelope components. The peptide ELISA used in this study appears to represent a simple technique employing chemically synthesized antigen for accurate and sensitive estimation of antibodies to the HIV group of nontransforming human retroviruses.  相似文献   
10.
Antibodies to surface antigens of intracellular naked vaccinia virus (INV) and in limited studies extracellular enveloped virus (EEV) were determined by single radial immunodiffusion tests (SRDT) with immobilized virions in agarose gels. Antibodies to INV were demonstrable in rabbit hyperimmune sera (one to four visible zones), smallpox convalescent sera and sera from re-vaccinated individuals. A difference in specificity of antibodies reacting with INV and EEV was detectable by SRDT. The SRDT provides a simple, reproducible and specific test for detection of antibodies against vaccinia or variola virus, but the technique requires large quantities of virions.  相似文献   
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