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91.
X-linked agammaglobulinemia (XLA) is an immunodeficiency caused by mutations in the Bruton tyrosine kinase (BTK) gene. Twenty Australian patients with an XLA phenotype, from 15 unrelated families, were found to have 14 mutations. Five of the mutations were previously described c.83G>A (p.R28H), c.862C>T (p.R288W), c.904G>A (p.R302G), c.1535T>C (p.L512P), c.700C>T (p.Q234X), while nine novel mutations were identified: four missense c.82C>A (p.R28S), c.494G>A (p.C165Y), c.464G>A (p.C155Y), c.1750G>A (p.G584E), one deletion c.142_144delAGAAGA (p.R48_G50del), and four splice site mutations c.241-2A>G, c.839+4A>G, c.1350-2A>G, c.1566+1G>A. Carrier analysis was performed in 10 mothers and 11 female relatives. The results of this study further support the notion that molecular genetic testing represents an important tool for definitive and early diagnosis of XLA and may allow accurate carrier status and prenatal diagnosis. 相似文献
92.
Immune regulation by novel costimulatory molecules 总被引:10,自引:0,他引:10
CD4 helper T (Th)-cells and the cytokines that they produce play essential regulatory roles in immune and autoimmune responses.
Th activation and differentiation is regulated by costimulatory receptors. CD28 and CTLA-4 are important in maintaining the
threshold of T-cell activation. ICOS and PD-1 are novel costimulatory receptors expressed on activated T-cells. B7-H3 recognizes
a putative costimulatory receptor on activated T-cells. Here we summarize the latest developments in the novel costimulatory
molecules and their roles in regulating Th activation, differentiation, and function. 相似文献
93.
The recent implication of Helicobacter pylori in the pathogenesis of gastritis-peptic ulcer syndrome and its relevance for the development of upper gastrointestinal malignancy warrant efficient methods for the detection and demonstration of the organism in biopsy specimens. We have compared 5 staining methods, namely, haematoxylin and eosin (H & E), immunohistochemistry (IHC), the silver staining HpSS, the alcian yellow-toluidine blue (Leung) method (A-Y) and Genta staining, for the demonstration of the organism in gastric biopsies taken from antrum, body and fundus of 118 patients who presented to our hospital with upper gastrointestinal symptoms. We found no significant differences in the efficacy of H & E, IHC, HpSS and A-Y in the demonstration of H. pylori in all 3 gastric sites. The least reproducible stain in our hands was the Genta stain. We conclude that H & E is adequate for the initial assessment of gastric biopsies in symptomatic upper gastrointestinal patients. This is because it is a well-tested, cheap and easy staining method, requiring a relatively short period of time to perform, with highly reproducible results. It has an added advantage of enabling simultaneous assessment of morphological changes accompanying H. pylori infection. When the density of the organism is expected to be low, we recommend addition of HpSS staining because of its high sensitivity and low cost. The disadvantages of the other staining methods (IHC, A-Y and Genta) are discussed. 相似文献
94.
Rat F2408 cells transformed by polyoma virus contain, in addition to integrated viral genomes, a small number (an average of 20–50 copies per cell) of nonintegrated viral DNA molecules. On the other hand, SV40-transformed rat cells contain only integrated viral genomes. SV40-transformed rat cells also differ from the polyoma transformants, in that they grow in soft agar medium at a much slower rate. Cells doubly transformed by polyoma and SV40 can be easily isolated following polyoma superinfection of SV40-transformed rat cells, as their rate of growth in agar is enhanced. These doubly transformed cells yield polyoma or SV40, respectively, after fusion with cells permissive for each virus. However, only polyoma-specific DNA sequences can be detected in these cells in a “free” state. 相似文献
95.
Bhattacharya SK Singh NK Prasad RC Sinha PR 《The Journal of the Association of Physicians of India》1998,46(8):675-677
Thirty four patients aged 14 to 65 years (18 males and 16 females) admitted to the University Hospital with various unusual and severe forms of adverse drug reactions were studied. It comprised of toxic epidermal necrolysis in 8 patients, systemic vasculitis in 7 of which 3 patients had gangrene of fingers and/or toes, severe erosive gastritis in 9 patients, Stevens-Johnson syndrome in 7 patients, thrombocytopenic purpura in 2 patients and generalised convulsions in 1 patient. Various drugs responsible for causing these adverse drug reactions included antibacterials, antimalarials, anticonvulsants, antituberculars and nonsteroidal anti-inflammatory drugs. Most of the patients recovered. However, 5 of the 8 patients having toxic epidermal necrolysis died of which 2 patients had developed tetanus as a preterminal event. In view of ongoing addition of newer drugs to the therapeutic armamentarium and an increasing incidence of various unusual and severe forms of adverse drug reactions, it is our contention that a separate adverse drug reaction monitoring cell should be established in every hospital setting. 相似文献
96.
Vascular tumors of the breast are uncommon. Perilobular hemangiomas, the commonest histologic subtype of breast hemangiomas, constitute majority of microscopic, vascular mammary tumors. Macroscopic hemangiomas and vascular hamartomas of the breast are distinctly rare. We describe a giant, vascular hamartoma of the right breast in a five year old girl and discuss pertinent literature. 相似文献
97.
Reported complications rates for the construction of intestinal stomas are high. Many of these complications result from improper construction, improper location, or other technical errors. In order to sample the techniques of stoma construction currently in use, a survey was conducted at the 69th Annual Clinical Congress of the American College of Surgeons in Atlanta in conjunction with our scientific exhibit "Complications of Intestinal Stomas." A total of 245 surgeons completed the questionnaire with a mean age of 47.8 years. The routine use of fascial-seromuscular tacking sutures and primary maturation of a loop colostomy in the presence of distal obstruction were among the most controversial technical points considered. Many other subtle but important principles of stoma construction were also discussed. In addition, the authors contend that many of the techniques currently in use result from an underemphasis on the importance of proper stoma construction in many surgical training programs. 相似文献
98.
In the first 3 papers of this series (Furshpan et al., 1986a, b; Potter et al., 1986), a sensitive microculture procedure was used to show that sympathetic principal neurons, dissociated from newborn or adult superior cervical ganglia and grown singly on cardiac myocytes, display adrenergic, cholinergic, and purinergic functions, sometimes in isolation but more often in combination. In this paper we describe additional effects on cardiac myocytes evoked by these neurons; the effects were excitatory and insensitive to adrenergic blocking agents (and to agents that block the inhibitory effects of acetylcholine and purines). In some of these microcultures, evidence consistent with secretion of serotonin was obtained; the nonadrenergic excitatory effect was diminished or abolished by serotonin blockers or reserpine. Further evidence for serotonergic transmission is presented in the accompanying paper by Sah and Matsumoto (1987). In other cases, an as-yet-unidentified agent "X" also produced a nonadrenergic excitation. The X effect characteristically required a prolonged train of neuronal impulses, had a time course of 50-200 sec, and was insensitive to agents that affected the other transmitters, including serotonin. In addition, we discuss 2 remarkable features of the transmitter repertoire of the microcultured sympathetic neurons: expression of the several transmitters in a variety of combinations, including at-least-quadruple function, and expression of the transmitters within a particular combination in varying relative strengths. The result is a diversity of transmitter release greater than that previously reported for vertebrate or invertebrate neurons. 相似文献
99.
Journal of Public Health - Few studies have been performed to investigate multiorgan failure occurring with extrapulmonary symptoms like diarrhea, anorexia, and vomiting. There has been no attempt... 相似文献
100.
Kerkar Shweta Shankar Arti Boynton-Jarrett Renee Harville Emily W. 《Maternal and child health journal》2021,25(3):479-486
Maternal and Child Health Journal - To investigate whether adverse childhood experiences are associated with miscarriage. The Gulf Resilience on Women’s Health Consortium recruited from... 相似文献