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101.
Severe combined immunodeficiency with B lymphocytes: in vitro correction of defective immunoglobulin production by addition of normal T lymphocytes. 总被引:3,自引:2,他引:3 下载免费PDF全文
R C Seeger R A Robins R H Stevens R B Klein D J Waldman P M Zeltzer S W Kessler 《Clinical and experimental immunology》1976,26(1):1-10
A 6 1/2-month-old male with severe combined immunodeficiency (SCID) had a low percentage and number of T cells (11%; 241/mm3) and a high percentage and number of B cells (52%; 1187/mm3) and null cells (37%; 868/mm3). In vitro studies were performed to determine if this child's primary defect involved differentiation of both T and B lymphocytes or if failure of B lymphocytes to differentiate into immunoglobulin producing cells was secondary to T lymphocyte abnormalities. Immunoglobulin production by lymphocytes in response to polyclonal mitogens (pokeweed mitogen and foetal calf serum) was measured by pulse-labelling cells with 3H-leucine and then precipitating cytoplasmic and secreted immunoglobulins with polyvalent anti-human immunoglobulin and S. aureus (Cowan strain I) protein A. The patient's lymphocytes did not synthesize immunoglobulins in vitro in response to mitogens. They did not suppress synthesis of immunoglobulins by normal lymphocytes. However, addition of normal purified T cells, which themselves did not synthesize immunoglobulins, enabled the patient's B lymphocytes to become immunoglobulin synthesizing and secreting cells. Gamma, mu, and light chains were secreted. This suggests that the primary abnormality was in the T-cell axis at the level of lymphoid stem cells or prothymocytes and that failure of B lymphocytes to become immunoglobulin-producing cells was secondary to this defect. 相似文献
102.
Joannis Theodorou Martine Raphaël Claude Bigorgne Christine Fourcade Chantal Lahet Gilles Cochet Marie-Paule Lefranc Philippe Gaulard Jean-Pierre Farcet 《The Journal of pathology》1994,174(4):233-242
The recombination events of the γ and β T-cell receptor (TCR) loci were analysed in a series of 39 peripheral T-cell lymphomas (PTCLs) in association with the expression of TCR chains. In TCR αβ PTCLs, 22/23 cases showed a γ-gene rearrangement while only 18/23 showed a concomitant β-gene rearrangement. The germline configuration of the β locus was found in angioimmunoblastic lymphadenopathy and lymphoepithelioid lymphomas. Three γδ PTCLs rearranged both γ and β genes. TCR silent PTCLs showed three different patterns of γ- and β-gene rearrangements. Three cases were in germline configuration for both loci; five cases had a rearranged γ and a germline β locus; and five cases had the two loci rearranged. Regarding the variable genes in the γ-rearranged alleles, members of the VγI subgroup were the most frequently presented (39/50), followed by VγII, VγIII, and VγIV (9/50, 1/50, and 1/50, respectively). Joining segment usage was as follows: J1 or J2 (32/50), JP1 or JP2 (17/50), and JP (1/50). Taken together, these data demonstrate that the γ locus is more frequently rearranged whatever the TCR expression. The γ-locus analysis provides a better diagnostic yield than the β locus in the study of PTCL clonality. 相似文献
103.
Detection of methicillin-resistant Staphylococcus aureus and simultaneous confirmation by automated nucleic acid extraction and real-time PCR 下载免费PDF全文
Grisold AJ Leitner E Mühlbauer G Marth E Kessler HH 《Journal of clinical microbiology》2002,40(7):2392-2397
A molecular assay for the simultaneous detection of a Staphylococcus aureus-specific gene and the mecA gene, responsible for the resistance to methicillin in staphylococci, was evaluated. The assay included an automated DNA extraction protocol conducted with a MagNA Pure instrument and real-time PCR conducted with a LightCycler instrument. The performance and robustness of the assay were evaluated for a suspension of methicillin-resistant S. aureus (MRSA) strain with a turbidity equivalent to a McFarland standard of 0.5, which was found to be the ideal working concentration. The specificity of the new molecular assay was tested with a panel of 30 gram-negative and gram-positive bacterial strains other than MRSA. No cross-reactivity was observed. In a clinical study, 109 isolates of MRSA were investigated. All clinical MRSA isolates gave positive results for the S. aureus-specific genomic target, and all but one were positive for the mecA gene. In conclusion, the new molecular assay was found to be quick, robust, and laborsaving, and it proved to be suitable for a routine molecular diagnostic laboratory. 相似文献
104.
Depression and level of disability are evaluated in acute and chronic low back pain (LBP) patients. To assess the possibility that some somatic symptoms are confounded with pain, the items of the Beck Depression Inventory arc divided into a cognitive-affective and somatic subscale. The sample consisted of 37 chronic LBP patients. 41 acute LBP patients, and 28 healthy participants. The level of disability was assessed by the Oswestry Low Back Pain Disability Questionnaire. Chronic LBP patients, but not acute LBP patients, have more depressive symptoms than controls. Additionally, chronic LBP patients report more somatic symptoms of depression (e.g.. emo ltional and self disturbance complaints) than cognitive-affective symptoms. Finally, correlation statistics reveal significant relations between the level of disability and depression scores. Whereas chronic patients show a significant correlation between the somatic subscale and level of disability, in acute patients the cognitive-affective subscale is significantly related to the level of disability. The findings suggest careful consideration of whether somatic symptoms of depression are related to pain when using self-report measurements of depression in pain patients. The separation of cognitive-affective and somatic symptoms of depression to evaluate pain problems seems appropriate. 相似文献
105.
Alain Leydet Véronique Barragan Bernard Boyer Jean-Pierre Roque Bernard Pucci André A. Pavia 《Macromolecular chemistry and physics.》1995,196(12):3877-3890
Three methyl 11-(N-acryloyl-N-alkylamino)undecanoates were synthesized from acryloyl chloride and amino-or alkylaminoundecanoic acid esters. These compounds were telomerized in the presence of 1-dodecanethiol as telogen to yield telomers with molecular weight lower than 5000. These telomers are likely to generate HIV inhibitor polyanions with good biocompatibility. The K/Kt value was assessed from a kinetic study of the telomerization reaction. NMR spectroscopy analysis indicates that the polymerization degree DP n are in good agreement with expectation for methyl 11-(N-acryloylamino)undecanoate. However, they were lower than expected for methyl 11-(N-acryloyl-N-alkylamino)undecanoate. 相似文献
106.
Alain Verloes Yves Gillerot Jean-Paul Langhendries Jean-Pierre Fryns Lucien Koulischer 《American journal of medical genetics. Part A》1992,43(4):669-677
We report on a case of neonatal hypothalamic hamartoblastoma with holoprosencephaly, Hirschsprung disease, and tetramelic postaxial polydactyly. Twenty-seven previous cases of congenital hypothalamic embryonic tumours with associated congenital defects are reviewed. A classification in isolated, associated, and syndromal forms is proposed. The difficulties encountered in differential diagnosis between the syndromal form (mainly represented by the Pallister-Hall syndrome) and related diseases as Smith-Lemli-Opitz type II, holoprosencephaly-polydactyly, orofaciodigital type VI and hydrolethalus syndromes are outlined. Two pathogenic mechanisms are discussed: a classical pleiotropic model and single sequence model. The latter is sufficient to delineate syndromal hypothalamic hamartoblastoma. With the former, syndromal hypothalamic hamartoblastoma cannot be clearly recognized in the absence of a CNS tumour, a child with syndromal hypothalamic hamartoblastoma cannot be reliably diagnosed as Pallister-Hall rather than another MCA syndrome, and, ultimately, the existence of Pallister-Hall syndrome could be questioned, as it could only be the extreme expression of one or several other syndromes. As this hypothesis cannot be proven or disproven at this point, the authors suggest creating the concept of multiplex phenotype. “Cerebro-Acro-Visceral Early lethality multiplex syndrome” is suggested to encompass all the ambiguous cases. Within this complex, an operative classification key is proposed. © 1992 Wiley-Liss, Inc. 相似文献
107.
Elabbassi EB Belghazi K Delanaud S Libert JP 《European journal of applied physiology》2004,92(6):679-682
Keeping premature newborns warm is crucial for their survival. Their ability to prevent excessive heat loss to the environment and to control their body temperature is limited. The risk of hypothermia is particularly important for low-birth-weight newborns with a large body surface area in relation to their mass of heat-producing tissues. The present study was performed to assess the body heat loss difference between small and large body-size premature newborns using two anthropomorphic thermal manikins of premature newborns of 900 g and 1,800 g (respective body surface areas of 0.086 and 0.150 m2). The dry heat loss from the six body segments of the small manikin (S) was measured and compared with that of the large manikin (L). The two manikins were exposed to five different environmental temperatures ranging between 29 and 35°C in a single-walled, air-heated closed incubator. The magnitudes of heat loss decreased significantly by 20.4% between the two manikins [small manikin 110.1 (44.3) W/m2 vs large manikin 87.6 (25.8) W/m2, mean values with one standard deviation]. The results obtained from the comparison of the heat loss measures from the two manikins confirm the fact that the heat loss increases with an increase in the ratio of the body surface area to body mass. The thermal manikin appears to provide an accurate method for the assessment of thermal conditions in neonatal care. 相似文献
108.
Jean-Pierre Monthard Marcel Camps Ahmed Belfkira Michel Chatzopoulos Robert Granger Luc Jorat Grard Noyel 《Macromolecular chemistry and physics.》1985,186(7):1519-1532
The relations between structure and isothermal, dielectric properties of poly(α-acetoxystyrene)s substituted in para position by ? OCOCH3 ( 1a ), ? OCOCH2CH3 ( 1b ), ? OCOCH2CH2CH3 ( 1c ), ? OCOC6H5 ( 1d ), ? OCOCH2CH2Cl ( 1f ) and ? OCOOCH3 ( 1g ) were studied. The dielectric constants, at 105 Hz and 20 ± 2°C, were found to be: 3,79 ( 1a ), 3,36 ( 1b ), 3,18 ( 1c ), 3,51 ( 1d ), 3,36 ( 1e ), 3,65 ( 1f ) and 3,07 ( 1g ). The polymers 1a – 1g do not show any α- or β-transition. Increasing bulkiness of the para substituent gives rise to a decreasing dielectric constant due to an increase of the degree of syndiotacticity, as determined from 1H and 13C NMR spectra. 相似文献
109.
Pierre Moine Colette Sauve Eric Vallee Jean-Pierre Bedos Esther Azoulay-Dupuis 《Clinical microbiology and infection》1997,3(6):608-615
Objective: To compare cefotaxime (CTX) to amoxicillin (AMO) (usually considered the definitive therapy for penicillinsusceptible Streptococcus pneumoniae infections) in an immunocompromised mouse pneumonia model.
Methods: Three S. pneumoniae clinical isolates were used: two serotype 19 strains, a penicillin-susceptible (Ps ) strain (penicillin MIC = 0.03 μ/mL) and a highly penicillin-resistant (Pr ) strain (penicillin MIC = 4 μ/mL), and one serotype 23F strain, a penicillin-cephalosporin-resistant (CFTR) strain (CTX MIC = 4 μ/mL).
Results: CTX activity in this mouse model of pneumonia induced by the highly penicillin-resistant strain of S. pneumoniae was lower than expected from its low MIC against this organism. Furthermore, AMO had greater efficacy than CTX against a CFTR S. pneumoniae strain.
Conclusion: Our data suggest that there is no major difference in the in vivo efficacy of the two agents, cefotaxime and amoxicillin, against penicillin-resistant and penicillin-cephalosporin-resistant S. pneumoniae. 相似文献
Methods: Three S. pneumoniae clinical isolates were used: two serotype 19 strains, a penicillin-susceptible (P
Results: CTX activity in this mouse model of pneumonia induced by the highly penicillin-resistant strain of S. pneumoniae was lower than expected from its low MIC against this organism. Furthermore, AMO had greater efficacy than CTX against a CFTR S. pneumoniae strain.
Conclusion: Our data suggest that there is no major difference in the in vivo efficacy of the two agents, cefotaxime and amoxicillin, against penicillin-resistant and penicillin-cephalosporin-resistant S. pneumoniae. 相似文献
110.
Emergency after-hour pharmacy services in many hospitals have been replaced by 24-hour, 7-day/week pharmacy services. A survey questionnaire was published in Hospital Pharmacy, February 1983, to be completed by hospital pharmacies that provide a pharmacist in the hospital 24 hours a day, 7-days a week. Usable responses were received from 185 hospitals. The type of hospitals and the number of beds of these hospitals varied greatly. The differing responses concerning staffing, scheduling, hours of the post-midnight shift, arrangement of vacations and holidays, the factors used in selling the concept to administration, and the handling of compensation are presented. 相似文献