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101.
Marrow transplantation was attempted in a 13-yr-old boy with congenital hypoplastic anemia who had never responded to corticosteroid therapy. Prior to the transplant, he had received 238 transfusions, at least 12 of which were from his father. He was prepared for grafting with antilymphocyte globulin, procarbazine, and total body irradiation (1000 rads). The patient, whose red cells were Group B, then received marrow cells from his Group O, histocompatible, sister. Thereafter, reticulocytes, Group O erythrocytes, and female leukocytes appeared in the peripheral blood. Erythroid precursors were seen in the patient's marrow for the first time in his life, and all lacked fluorescent Y chromosomes. Dividing cells were all female. After initially progressing well, the patient developed interstitial pneumonia and died 55 days after the transplant. The successful erythroid graft suggested that this patient's failure to produce red blood cells was due to a defective stem cell rather than to a humoral defect, plasma inhibitor, or abnormal marrow microenvironment. It suggested further that sibling marrow may be engrafted in patients who have received multiple transfusions, even from a parent.  相似文献   
102.
103.
The cytoskeleton in Chediak-Higashi syndrome fibroblasts   总被引:2,自引:0,他引:2  
The Chediak-Higashi syndrome (CHS) trait is expressed in cultured human skin fibroblasts as an abnormal perinuclear concentration of moderately enlarged lysosomes. The cytoskeleton of CHS fibroblasts appears intact. Microtubules are normal in number and morphology, as assessed by colchicine binding studies, antitubulin immunofluorescence, and electron microscopy. Deformability by shear force is unaltered and microfilaments are abundant. However, CHS lysosomes appear to interact abnormally with the cytoskeleton, since the perinculear aggregation partially disperses after depolymerization of cell microtubules with colchicine. These results suggest that CHS is associated with a defect of either the lysosomal membrane itself or of lysosomal membrane- microtubule interaction.  相似文献   
104.
Human neonatal neutrophils manifest decreases in mobility, adherence, and emigration compared with adult neutrophils that may contribute to the increased susceptibility of neonates to infection. In a developmental rabbit model, we show a reduced ability of neutrophils from 1-day-old rabbit pups to emigrate to inflamed peritoneium (3.7 +/- 0.35 x 10(6) neutrophils/mL peritoneal exudate) compared with 14-day- old (8.5 +/- 0.7 x 10(6)/mL) and adult rabbits (9.4 +/- 1.4 x 10(6) mL, P < .05) despite significantly increased blood neutrophil counts. Because the reductions in functional Mac-1 (CD11b/CD18) as well as the amount of surface L-selectin are hypothesized to be primarily responsible for the differences in human neonatal neutrophil mobility, we examined CD11b/CD18 and L-selectin in our model. Using flow cytometric analysis we found that similar to human neonates, neutrophils from 1-day-old rabbit pups had 57% of adult rabbit levels of L-selectin and, in contrast with adults, failed to show significant decreases in L-selectin after chemotactic stimulation. In addition, neutrophils from 1-day-old pups compared with adults showed a significantly diminished capacity to upregulate CD11b/CD18 after chemotactic stimulation in vitro, or after emigration to the inflamed peritoneum. Systemic administration of anti-L-selectin monoclonal antibody (MoAb) resulted in significant reduction in peritoneal neutrophils in adult (47%, P < .05) and 14-day-old rabbits (47%, P < .05), but was without effect in 1-day-old rabbits. Administration of anti-CD18 MoAb resulted in significant reduction in peritoneal neutrophil accumulation in all age groups though less in 1 day and 14 day (58% and 65%, respectively) than in adults (91%, P < .05). Only in the 14-day-old rabbits was there an additive effect of anti-L-selectin and anti-CD18 MoAbs compared with anti-CD18 alone (84% v 65%, P < .05). The findings in this in vivo rabbit model support the hypothesis that the previously described in vitro defects in human neonatal L-selectin and CD11b/CD18 may be major contributors to human neonatal inflammatory deficits.  相似文献   
105.
Introduction: We report the electrodiagnostic (EDX) features of 32 patients with surgically verified true neurogenic thoracic outlet syndrome (TN‐TOS). Methods: Retrospective record review. Results: We found uniform EDX evidence of a chronic axon loss process that affected the lower portion of the brachial plexus and disproportionately involved the T1 more than the C8 sensory and motor fibers. Because of this relationship, the medial antebrachial cutaneous sensory nerve (T1) and median motor (T1 > C8) study combination was abnormal in 89%, whereas response combinations that primarily assessed the C8 fibers were less frequently affected. Conclusions: The characteristic EDX features of TN‐TOS are T1 > C8 nerve fiber involvement. A comprehensive EDX examination of the lower plexus with contralateral comparison studies is imperative to diagnose this disorder accurately. Muscle Nerve 49 : 724–727, 2014  相似文献   
106.
AimsThe aim of the literature review was to identify new and emerging out of hospital emergency care roles and to describe their activity and impact.BackgroundDemographic changes, increased demands for health services, altered working practices, and health system economic pressures have led to the development of a disparate set of new health care roles.Data sourcesMEDLINE, EMBASE and CINAHL databases, and the two search engines Google and Google Scholar were searched for contemporary studies in the identified study area.Review methodsAll publications identified through the search were assessed for relevance. Those that discussed new roles were included (n = 34) and empirical studies (n = 14) analysed in detail.ResultsEmergency care and paramedic practitioner roles (ECP & PP) are having an impact on patient care, including an average 25% reduction in the conveyance rate to hospital, improved inter-professional working, immediacy of treatment and referral, and high patient satisfaction. Limited economic data suggests savings of between £31 (USD 55) and £37 (USD 65) per case when ECPs replace standard ambulance responders. Concerns have been expressed about patient safety, recruitment and training levels, regulatory and role implementation issues.ConclusionFurther work is required to fully understand the patient safety, clinical practice, professional role and financial implications of these new roles.  相似文献   
107.
108.
The objective of this study was to determine whether the proposed Malan radiological sinusitis typing (RST) system facilitated a level of agreement and ease of use comparable with the Lund–Mackay (LM) system for chronic rhinosinusitis. Ten observers (one otolaryngologist and nine radiologists), in two separate centres (regional and tertiary), blinded to all clinical data, used these two systems to independently and randomly score and type 15 sets of scans, recording the time to score each film. Using unweighted kappa scores, both methods facilitated a moderate level of agreement, slightly better with the LM system. The Malan system is more time efficient. Preliminarily, this study shows that the Malan RST system is easy to apply with a comparable level of agreement. The Malan RST system is a focused attempt at classifying disease extent radiologically and correlating it to a surgical approach. It emphasizes that scoring systems are vulnerable and proves to be superior to the LM system as a surgical planning tool. To score sinus disease, a Quality‐of‐Life questionnaire in association with this typing method is more appropriate.  相似文献   
109.
亚临床甲状腺功能亢进和甲状腺功能减退属于试验诊断。2002年美国甲状腺协会、美国临床内分泌医师协会和内分泌腺协会的委员组成的一个专家小组,明确了亚临床甲状腺疾病的概念,回顾了涉及风险和治疗益处的文献,并且建议进行评估和人口筛查。  相似文献   
110.
Topotecan (1.5 mg/m(2)/day for 5 consecutive days of a 21-day cycle) is an established recurrent ovarian cancer treatment, but myelosuppression can be dose limiting. This study evaluates the activity and tolerability of low-dose topotecan in our clinical experience. Case records were reviewed for patients with recurrent ovarian cancer in first through third relapse. Eligible patients had received > or =2 cycles of < or =1.25 mg/m(2) topotecan. Adverse events were evaluated using laboratory and clinical evaluation data. Twenty-seven eligible patients, most with advanced disease, received a total of 209 cycles (median, six cycles). Grade 3 or 4 hematologic toxicities during 184 cycles in 24 assessed patients were neutropenia, leukopenia, thrombocytopenia, and anemia in 35%, 28%, 36%, and 11% of cycles, and 21, 19, 16, and 10 patients, respectively. Only four grade 4 toxicities occurred: anemia (one) and thrombocytopenia (three). Myelosuppression was reversible, noncumulative, and manageable. Moreover, nonhematologic toxicity was generally mild to moderate, and the only two grade 3 events were constipation and deep vein thrombosis. Low-dose topotecan was active in this setting. Lower-dose topotecan is generally well tolerated and active in patients with pretreated ovarian cancer. Prospective clinical trials of low-dose topotecan in recurrent ovarian cancer are warranted.  相似文献   
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