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1.
Todd M. Getz 《Transfusion and apheresis science》2019,58(1):12-15
Platelet transfusions are a life-saving medical intervention used for the treatment of thrombocytopenia or hemorrhage. Extensive research has gone into trying to understand how to store platelets prior to the transfusion event. Much has been learned about storage bag materials, synthetic solutions, and how temperature impacts platelet viability and function. While room temperature storage of platelets preserves 24-hour in vivo platelet recovery and survival there is a greater risk for bacterial growth. Therefore, cold storage of platelets has become attractive due to the reduction in potential bacterial proliferation and the maintenance of platelet function beyond 5 days of storage. Cold stored platelets, however, have their own set of challenges. Cold stored platelets become activated through several mechanisms. The morphological and molecular changes that occur due to cold exposure enhance their ability to participate in the hemostatic process at the cost of rapid clearance from circulation. This review focuses on the underlying mechanisms leading to cold platelet activation and the receptor modifications involved in platelet clearance. 相似文献
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Gad Degani Rakefet Sharon Michael Warburg 《General and comparative endocrinology》1997,106(3):356-360
Gonadal steroid levels were determined in the ovary ofSalamandra salamandra infraimmaculataduring the reproductive cycle in populations from a xeric region in northern Israel. Varying proportions of previtellogenic and vitellogenic oocytes were present throughout the year, and mature oocytes were present in winter and spring. The numbers of mature oocytes were greater between December and April, after parturition. The levels of 17β-estradiol and testosterone rose during oocyte vitellogenesis and maturation. Levels of progesterone and 17α-hydroxy progesterone appeared to be related to the level of vitellogenesis. Gravid females contained greater quantities of all four steroids than did nongravid females. 相似文献
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Diagnosis of scaphoid fractures:A prospective multicenter study of 1,052 patients with 160 fractures
Bo Munk Johnny Fr kj r Claus Falck Larsen Hans Gad Johannsen Lars Lundager Rasmussen Annette Edal Lilla Demeney Rasmussen 《Acta orthopaedica》1995,66(4):359-360
In a prospective multicenter study of 1,052 patients with clinical signs of a scaphoid fracture, mammo-graphic films and fine intensifying screens were used at the radiographic examination. 5 standardized projections including 3 special projections focused on the scaphoid were taken. 150 fractures were diagnosed at the first examination but in 10 cases the fracture was first diagnosed at a second radiographic examination after 10-14 days.
The second examination still seems mandatory despite the use of high quality radiographs with optimal spatial resolution and contrast, and the value of supplementary special projections. 相似文献
The second examination still seems mandatory despite the use of high quality radiographs with optimal spatial resolution and contrast, and the value of supplementary special projections. 相似文献
6.
In 224 consecutive patients with hormone-resistant prostatic cancer referred to 2 European Cancer Centres for palliation of painful bone metastases the one year survival for all patients was 24% (2-year survival: 7%). The median survival was 8 months. In univariate analyses the following prognostic factors were identified: performance status, serum creatinine, alkaline phosphatase, duration of response to primary hormone treatment, degree of bone scan involvement and hemoglobin. Multivariate analyses confirmed the four first parameters to be independent factors. A prognostic model was established (no or one risk factors vs 2 risk factors vs 3 or 4 risk factors) based on performance status, creatinine, alkaline phosphatase and hormone response duration. The median survival of these groups was 10 months, 6 months and 3 months, respectively. This model proved to be discriminative in an external data set of 214 patients with hormone-resistant prostatic cancer entered in two prospective trials. The above differences in outcome between readily and simply defined prognostic groups are greater than the differences one can realistically hope to produce using new treatment strategies. These prognostic factors should be taken into account both in the design and interpretation of clinical studies dealing with the treatment of hormone-resistant progressing prostatic cancer and painful bone metastases. 相似文献
7.
Maya Koronyo-Hamaoui Eva Gak Daniel Stein Amos Frisch Yardena Danziger Shani Leor Elena Michaelovsky Neil Laufer Cynthia Carel Silvana Fennig Marc Mimouni Alan Apter Boleslav Goldman Gad Barkai Abraham Weizman 《American journal of medical genetics. Part B, Neuropsychiatric genetics》2004,(1):76-80
The human small-conductance Ca(2+)-activated potassium channel gene KCNN3 has been involved in mechanisms underlying neuronal function and plasticity. A multiallelic CAG repeat polymorphism within the KCNN3 has been associated with schizophrenia and bipolar disorder. We have previously reported in a family-based study that longer CAG repeats are preferentially transmitted to patients with anorexia nervosa (AN). The present study extends the analysis of KCNN3 allele distribution to a larger series of AN female patients and control groups, incorporating information on ethnicity and co-morbidities associated with AN. The data analysis is presented while considering separately the two alleles of each individual, namely a minor (shorter) and a major (longer) allele. This study has found that the KCNN3 allele distribution in the general Israeli population does not differ significantly in at least four Jewish ethnic groups of Ashkenazi, North African, Iraqi, and Yemenite origin. These have been used as control groups in a matched case-control analysis that has demonstrated a significant over-representation of KCNN3 alleles with longer CAG repeats among AN patients (P < 0.001 for the major allele and P = 0.035 for allele sum). Under dichotomization, a significantly higher prevalence of the L allele (>19 repeats) has been observed among AN patients (P < 0.001). While considering AN and co-morbid phenotypes, a tendency towards longer (L) alleles has been observed in the subset of patients with obsessive-compulsive disorder (OCD) co-morbidity. These findings further implicate KCNN3 as a significant contributor to predisposition to AN. 相似文献
8.
S. Shahabuddin I. Al-Ayed M. O. Gad El-Rab M. I. Qureshi 《Clinical and Vaccine Immunology : CVI》1998,5(5):632-635
The age-related changes in absolute and percentage values of lymphocyte subsets in the peripheral blood of healthy children of different ages (1 month to 13 years) were studied by flow cytometry. The absolute and percentage values for most lymphocyte subpopulations differed substantially with age. Comparisons among age groups from infants through adults revealed progressive declines in the absolute numbers of leukocytes, total lymphocytes, and T, B, and natural killer (NK) cells. The percentages of T cells increased with age. Within the T-lymphocyte population, the CD8+ subset increased but the CD4+ subset decreased, resulting in a declining CD4+/CD8+ ratio. The percentage of B cells declined, but that of NK cells remained unchanged. The percentage of HLA-DR+ T cells increased over time, but their number changed inconsistently. Our findings confirm and extend earlier reports on age-related changes in lymphocyte subpopulations. These data should be useful in the interpretation of disease-related changes, as well as therapy-dependent alterations, in lymphocyte subsets in children of different age groups. 相似文献
9.
Widespread IgE-mediated hypersensitivity in the Sudan to the 'green nimitti' midge, Cladotanytarsus lewisi (Diptera: Chironomidae) II. Identification of a major allergen. 下载免费PDF全文
A major allergen has been identified in an aqueous extract of the 'green nimitti' midge, Cladotanytarsus lewisi (Diptera: Chironomidae). Following chromatography on Sephadex G-100 allergenic activity, as assessed by skin ('prick') testing, eluted as two closely related peaks (pools I and II) at about 50% bed volume. When these pools were applied separately to columns of CM-cellulose, activity in each eluted with 0 . 05 M NaCl. Isoelectric focusing of the unfractionated allergen gave a single peak of activity at pI 4 . 3. By SDS--PAGE, biological activity in the whole 'green nimitti' extract and the material eluting from both pools I and II of the Sephadex G-100 column migrated to the same positions and were associated with a molecular size of 15,000--20,000 daltons. Skin test reactivity of the unfractionated material and the Sephadex G-100 pool I and II eluates were all destroyed following incubation with trypsin, chymotrypsin, thermolysin and neuraminidase. These experiments indicate that a major allergen derived from the 'green nimitti' midge, a cause of widespread and severe immediate-type allergy in the Sudan, is an acidic glycoprotein of 15,000--20,000 molecular weight. 相似文献
10.
Detection of Intimins α, β, γ, and δ, Four Intimin Derivatives Expressed by Attaching and Effacing Microbial Pathogens 下载免费PDF全文
Jeannette Adu-Bobie Gad Frankel Christopher Bain Azizedite Guedes Goncalves Luiz R. Trabulsi Gill Douce Stuart Knutton Gordon Dougan 《Journal of clinical microbiology》1998,36(3):662-668
Intimins are outer membrane proteins expressed by enteric bacterial pathogens capable of inducing intestinal attachment-and-effacement lesions. A eukaryotic cell-binding domain is located within a 280-amino-acid (Int280) carboxy terminus of intimin polypeptides. Polyclonal antiserum was raised against Int280 from enteropathogenic Escherichia coli (EPEC) serotypes O127:H6 and O114:H2 (anti-Int280-H6 and anti-Int280-H2, respectively), and Western blot analysis was used to explore the immunological relationship between the intimin polypeptides expressed by different clinical EPEC and enterohemorrhagic E. coli (EHEC) isolates, a rabbit diarrheagenic E. coli strain (RDEC-1), and Citrobacter rodentium. Anti-Int280-H6 serum reacted strongly with some EPEC serotypes, whereas anti-Int280-H2 serum reacted strongly with strains belonging to different EPEC and EHEC serotypes, RDEC-1, and C. rodentium. These observations were confirmed by using purified Int280 in an enzyme-linked immunosorbent assay and by immunogold and immunofluorescence labelling of whole bacterial cells. Some bacterial strains were recognized poorly by either antiserum (e.g., EPEC O86:H34 and EHEC O157:H7). By using PCR primers designed on the basis of the intimin-encoding eae gene sequences of serotype O127:H6, O114:H2, and O86:H34 EPEC and serotype O157:H7 EHEC, we could distinguish between different eae gene derivatives. Accordingly, the different intimin types were designated α, β, δ, and γ, respectively. 相似文献