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91.
Th activation of red cells is characterized by agglutination with the peanut lectin from Arachis hypogaea and is diminished by treatment with proteolytic enzymes. The first cases of Th activation were associated with bacterial infections. More recently, a high incidence of Th activation in congenital hypoplastic anemia has been reported, along with the finding that 13.5 percent of cord bloods are Th activated. The incidence of Th reactivity in newborn infants was confirmed by studying 200 paired samples of maternal and cord blood. Twenty-two (11%) of the cord samples and 13 (6.5%) of the maternal samples were Th activated. In 6 paired samples (6/22), both the mother and child had Th activation, a finding that demonstrates a high degree of concordance. Additionally, 3 (6%) of 50 pregnant women were Th positive. These findings indicate that Th activation is another of the red cell antigen alterations related to pregnancy. 相似文献
92.
Subunit composition of plasma von Willebrand factor in patients with the myeloproliferative syndrome 总被引:2,自引:0,他引:2
In order to evaluate the role of proteolysis in acquired von Willebrand's disease (vWD) associated with the myeloproliferative syndrome, we have determined the relative quantity of von Willebrand factor (vWF) fragments as compared with the intact 225 kDa subunit in four patients. The plasma vWF of each individual lacked large multimers; each had a prolonged bleeding time; and both platelet and leukocyte counts were elevated. Plasma was obtained from blood drawn into 1 mmol/L leupeptin, 6 mmol/L N-ethylmaleimide, and 5 mmol/L EDTA to prevent in vitro proteolysis. vWF was isolated from plasma by immunoadsorbent chromatography, reduced, subjected to SDS-5% polyacrylamide gel electrophoresis, and immunoblotted with a mixture of 55 anti-vWF monoclonal antibodies. In three patients with essential thrombocytosis (ET) the 176 and 140 kDa fragments were increased in proportion to the intact 225 kDa subunit indicating increased proteolysis. Treatment of one ET patient with CCNU (Lomustine) decreased the platelet count and, to a lesser extent, the white blood cell count. This was associated with a correction of the bleeding time, a partial correction of the multimeric abnormality, and a lessening of vWF cleavage. In a patient with polycythemia rubra vera (PRV) the proportion of the 176 kDa fragment was increased to the upper limit of normal but there was no definite evidence of increased proteolysis. These studies provide evidence that proteolysis plays a role in the acquired von Willebrand's disease associated with the myeloproliferative syndrome. However, other mechanisms must also be considered. 相似文献
93.
Longacre TA; Foucar K; Crago S; Chen IM; Griffith B; Dressler L; McConnell TS; Duncan M; Gribble J 《Blood》1989,73(2):543-552
Morphologically distinct lymphoid cells with homogeneous, condensed chromatin and scant cytoplasm can be observed in large numbers in the bone marrow of children with a variety of hematologic and nonhematologic disorders. In some patients, these cells may account for greater than 50% of the bone marrow cells, creating a picture that can be confused with acute lymphoblastic leukemia (ALL) or metastatic tumor. Although originally called hematogones (HGs), a variety of other names have been proposed for these unique cells. The clinical significance of expanded HGs has not been resolved, and the biologic features of these cells are incompletely described. In this study, we correlate the clinical, morphologic, cytochemical, flow cytometric, molecular, and cytogenetic properties of bone marrow samples from 12 children with substantial numbers of HGs (range 8% to 55% of bone marrow cells). Diagnoses in these patients included anemia, four; neutropenia, one; anemia and neutropenia, one; idiopathic thrombocytopenic purpura, two; retinoblastoma, two; Ewing's sarcoma, one; and germ cell tumor, one. Flow cytometric analyses of bone marrow cells demonstrated a spectrum extending from early B-cell precursors (CD10+, CD19+, TdT+, HLA-Dr+) to mature surface immunoglobulin-bearing B cells in these patients, corroborating our morphologic impression of HGs, intermediate forms, and mature lymphocytes. DNA content was normal, and no clonal abnormality was identified by either cytogenetic or immunoglobulin and T-cell receptor (TCR) gene rearrangement studies. Follow-up ranged from 3 months to 3 years. None of the patients has developed acute leukemia or bone marrow involvement by solid tumor. The possible role of HGs in immune recovery and hematopoiesis is presented. 相似文献
94.
95.
Takahashi H; Handa M; Watanabe K; Ando Y; Nagayama R; Hattori A; Shibata A; Federici AB; Ruggeri ZM; Zimmerman TS 《Blood》1984,64(6):1254-1262
We studied four patients who showed aggregation of platelets in platelet-rich plasma at lower concentrations of ristocetin than those required for normal platelet-rich plasma and who demonstrated an increased capacity of the platelets to bind normal von Willebrand factor. The four patients were from two Japanese families. Platelets from one family aggregated spontaneously in vitro, and platelets from both families aggregated upon the addition of normal plasma and cryoprecipitate, in the absence of ristocetin or other agonists. Analysis of the multimeric composition of von Willebrand factor by sodium dodecyl sulfate-agarose gel electrophoresis revealed a decrease in large multimers or a decrease in both large and intermediate multimers in plasma, but normal multimers in platelets. 1-Deamino-[8-D- arginine]-vasopressin caused by an immediate appearance of larger multimers in plasma, followed by the rapid disappearance of these multimers from circulating plasma. Analysis of platelet membrane glycoproteins from the patients showed that there were two distinct bands in the glycoprotein I region; one migrated in a slower region and the other in a faster region than normal glycoprotein Ib. We suggest that the platelet receptor abnormality in these patients is related to this abnormality of glycoprotein Ib. 相似文献
96.
Despite the use of HLA-matched platelets for alloimmunized recipients, transfusion failures occur. In order to reduce these failures, we investigated the use of a radiolabeled antiglobulin technique for platelet crossmatching. The principle of the test is that of an indirect Coombs test using 125I labeled goat anti-human IgG. Incompatibility is determined by calculating a radioactivity antiglobulin test (RAGT) index. Using this technique, we performed 89 crossmatches on 19 leukemic or aplastic patients who were refractory to random donor platelets and receiving varying degrees of HLA-matched platelets. Effectiveness of the transfusion was assessed from the posttransfusion corrected platelet count increment (CCI) determined at 1 and 20 hr. When the RAGT index was 1.9 or less, the mean CCI at 1 lhr was 17,570 +/- 7003/cu mm, n = 55. When the RAGT index was 2.0 or greater, the mean CCI was 4237 +/- 4100/cu mm, n = 34. At 20 hr when the RAGT index was 1.9 or less, the mean CCI was 8722 +/- 3143/cu mm, n = 33, and when the index was 2.0 or greater, the mean CCI was 571 +/- 1286/cu mm, n = 23. Using this technique, one false negative resulted. Nine positive crossmatches with good increments at 1 hr were found; at 20 hr, however, the survival of these units was zero. These data suggest that this method is a useful adjunct in the selection of platelets in the refractory patient. 相似文献
97.
Background
Obesity is a global epidemic with important health care and financial implications. The cold pressor test (CPT) which is considered to be a sympathy-excitatory manoeuvre is a simple, noninvasive and validated test. The objective of this study was to assess and compare the cardiovascular response to cold pressor test in non-obese and obese healthy adults.Methods
The study included 400 subjects, of which the study group included 200 adults who had body mass index (BMI) of more than 30 Kg/m,2 and 200 non-obese adults were enrolled as controls with BMI less than 25 kg/m2. The study was conducted for a period of two months. CPT was used to assess cardiac response to acute cold exposure in the present study. Baseline systolic and diastolic blood pressure recording was done using mercury sphygmomanometer during resting condition and following cold pressor test. The results were expressed as mean, standard deviation, and data were analyzed using ANOVA test. P < 0.05 was considered statistically significant.Results
The mean change in systolic blood pressure before and after cold pressor test (CPT) was less in obese (7.12 ± 5.28) as compared to non-obese subjects (10.38 ±6.35). This was statistically significant which indicates impaired sympathetic function in otherwise healthy obese.Conclusion
The study concluded that blood pressure response to cold pressor test was reduced in obese compared to non-obese subjects indicating reduced sympathetic activity in healthy obese adults. 相似文献98.
99.
Riall TS Stager VM Nealon WH Townsend CM Kuo YF Goodwin JS Freeman JL 《Journal of the American College of Surgeons》2007,204(5):803-13; discussion 813-4
BACKGROUND: Recent small studies have reported an incidence of 23% to 39% for additional primary cancers in patients with intraductal papillary mucinous neoplasms (IPMN) of the pancreas. There have been no population-based studies evaluating this incidence rate. METHODS: Using the Surveillance, Epidemiology, and End Results (SEER) database (1983 to 1991), we identified all patients with primary pancreatic cancers (sporadic and adenocarcinomas arising in IPMNs). We determined the incidence of additional primary cancers that developed either before or after the diagnosis of invasive IPMN and compared it to the incidence of additional primary cancers in patients with sporadic pancreatic adenocarcinoma. RESULTS: Nineteen thousand six hundred forty-seven patients were reported with pancreatic cancer. Ninety-five percent of cancers were sporadic and 5.0% were invasive IPMNs. Ten point three percent had one or more extra-pancreatic primary cancers in addition to their pancreatic primary (10.3% in patients with sporadic adenocarcinoma and 10.1% in patients with invasive IPMNs, p = NS). The most common sites of additional primary cancers were colorectal (20.1%), breast (19.9%), prostate (16.6%), urinary system (11.1%), and lung (9.8%). In the 2,017 patients with additional primary cancer, 86% occurred before the diagnosis of pancreatic cancer and 14% occurred after the diagnosis of pancreatic cancer. CONCLUSIONS: Our population-based analysis shows that the incidence of additional primary malignancies in patients with invasive IPMNs is 10%. Although not as high as previously reported in smaller studies, the incidence is significant and comparable to the incidence seen in patients with adenocarcinoma. Surveillance for other common malignancies in patients with IPMNs and pancreatic adenocarcinomas should be performed. 相似文献
100.