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排序方式: 共有412条查询结果,搜索用时 15 毫秒
1.
Rigor and resistance to stretch in vertebrate smooth muscle 总被引:2,自引:0,他引:2
2.
OBJECTIVE: Because the survival rate has increased for extremely low birth weight neonates, many have raised the concern that the rate of developmental disability among survivors will also increase. To address this concern, we analyzed changes over time in survival and major neurosensory impairment in a sample of extremely low birth weight infants born between July 1, 1979, and June 30, 1994. METHODS: The study sample included 513 infants with birth weights of 501 to 800 g who were cared for in either of the two neonatal intensive care units that serve a 17-county region in northwest North Carolina and who were born to mothers residing in that region. At 1 year of age (corrected for gestation), survivors were examined by a pediatrician and were tested using the Bayley Scales of Infant Development. Major neurosensory impairment was defined as cerebral palsy, a Bayley Mental Developmental Index <68, or blindness. A total of 209/216 (97%) of survivors were examined at 1 year of age. Epoch of birth was defined as follows: epoch 1, July 1, 1979 to June 30, 1984; epoch 2, July 1, 1984 to June 30, 1989; and epoch 3, July 1, 1989 to June 30, 1994. RESULTS: Survival rates for epochs 1, 2, and 3 were, respectively, 24/120 (20%), 63/175 (36%), and 129/218 (59%). In contrast, the proportions with a major neurosensory impairment did not increase over time; rates for successive epochs were 6/24 (25%), 17/61 (28%), and 26/124 (21%). Rates of cerebral palsy were 3/24 (13%), 12/61 (20%), and 9/124 (7%); rates of delayed mental development were 4/24 (17%), 12/61 (20%), and 17/124 (14%); and rates of blindness were 2/24 (8%), 0/62, and 5/124 (4%), respectively. CONCLUSIONS: This analysis suggests that the increasing survival of extremely low birth weight neonates since the late 1970s has not resulted in an increased rate of major developmental problems identifiable at 1 year of age. 相似文献
3.
Jelinek J; Fairbairn LJ; Dexter TM; Rafferty JA; Stocking C; Ostertag W; Margison GP 《Blood》1996,87(5):1957-1961
A human O6-alkylguanine-DNA-alkyltransferase (ATase) cDNA-containing retrovirus was used to infect murine long-term primary bone marrow cultures. High levels of ATase expression were obtained, and colony- forming cells of the granulocyte-macrophage lineage from the cultures transduced with the human ATase retrovirus were three times more resistant to the alkylating agent, N-methyl-N-nitrosourea (MNU), than control cultures. Furthermore, expression of the human ATase protected long-term hematopoiesis, measured as the output of progenitor cells to the nonadherent fraction of the culture, against the cytotoxic effects of repeated exposures to MNU. These results clearly show that a human ATase cDNA-containing retrovirus can be used to infect long-term primary bone marrow cultures and that this attenuates their sensitivity to nitrosoureas. 相似文献
4.
Background Negative surgical margins minimize the risk of local recurrence after breast-conserving surgery. Intraoperative frozen section
analysis (FSA) is one method for margin evaluation. We retrospectively analyzed records of patients who received breast-conserving
therapy with intraoperative FSA of the lumpectomy cavity to assess re-excision rates and local control.
Methods Records were retrospectively reviewed for individuals who underwent breast-conserving surgery for ductal carcinoma in situ
(DCIS) or invasive carcinoma between 1993 and 2003. Inclusion criteria were a minimum of 2 years follow-up and intact tumor
at the time of operation. The major outcome measure was local recurrence. The Kaplan-Meier test was used to evaluate local
recurrence rates between groups.
Results 290 subjects with an average age of 57.2 years (range 27–89) underwent 292 lumpectomies with FSA. 11.3% had DCIS, 73.3% had
infiltrating ductal, 5.8% had infiltrating lobular, and 9.6% exhibited other forms of invasive carcinoma. 70 subjects underwent
additional resection at the time of breast surgery, 16 underwent subsequent re-excision, and 17 underwent subsequent mastectomy.
At a median follow-up of 53.4 months (range 5.8–137.8), there were six local recurrences (2.74%) in patients who had breast-conserving
procedures and two local recurrences in patients who underwent mastectomy. There were no statistically significant associations
among local recurrence rate, tumor size, nodal status, or overall stage. Local recurrences were higher in patients with DCIS
compared with invasive carcinoma, and tumors >2cm.
Conclusions Intraoperative FSA allows resection of suspicious or positive margins at the time of lumpectomy and results in low rates of
local recurrence and re-excision. The low local recurrence rate reported here is comparable to those reported with other margin
assessment techniques. 相似文献
5.
6.
CALLA-positive myeloma: an aggressive subtype with poor survival 总被引:5,自引:0,他引:5
Detailed immunotyping was carried out on 21 direct myeloma bone marrow aspirates and eight human myeloma cell lines. Four previously untreated common acute lymphoblastic leukemia antigen (CALLA)-positive myeloma patients were identified and six of eight cell lines (75%) were also positive. CALLA positivity, as part of an immature B phenotype, was found to correlate with very aggressive clinical disease: median survival six months v 56 months for the CALLA-negative group. 相似文献
7.
Marsh JC; Will AJ; Hows JM; Sartori P; Darbyshire PJ; Williamson PJ; Oscier DG; Dexter TM; Testa NG 《Blood》1992,79(12):3138-3144
We have used the long-term bone marrow culture (LTBMC) system to analyze hematopoiesis in three patients with dyskeratosis congenita (DC), two of whom had aplastic anemia, and the third had a normal blood count (apart from mild macrocytosis) and normal BM cellularity. Hematopoiesis was severely defective in all three patients, as measured by a low incidence of colony-forming cells and a low level of hematopoiesis in LTBMC. The function of the marrow stroma was normal in its ability to support the growth of hematopoietic progenitors from normal marrows seeded onto them in all three cases, but the generation of hematopoietic progenitors from patients marrow cells inoculated onto normal stromas was reduced, thus suggesting the defect to be of stem cell origin. The parents and unaffected brother of one of the families have also been studied in LTBMC and all showed normal hematopoietic and stromal cell function. From this study we speculate that there are some similarities between DC and the defect in the W/Wv mouse. 相似文献
8.
C. Beglinger MD C. Knezevic MD L. Jeker U. Grötzinger MD PD Dr. K. Gyr MD MPH & TM 《Digestive diseases and sciences》1983,28(4):350-352
In five conscious dogs with chronic gastric fistulas we studied the effect of somatostatin solutions on pentagastrin-stimulated acid secretion. Somatostatin was dissolved in 0.154 M NaCl alone or in the same amount of saline to which dog albumin had been added to give a 0.5% solution. Somatostatin produced a dose-dependent inhibition of pentagastrin-stimulated gastric secretion. However, the inhibition was significantly less when somatostatin was dissolved in saline as compared to saline plus albumin. This study suggests that albumin should be added to somatostatin solutions to preserve biological activity, and it confirms previous reports indicating that, without albumin, basic peptides have a tendency to stick to infusion systems. 相似文献
9.
10.
手术是脉管性病变治疗的一种手段,其主要作用是与放射治疗及各种药物治疗协同作用。对于血管瘤患者,手术仅限于普萘洛尔治疗无效,出现并发症及位于眼部的病变。整形手术可使血管瘤消退后遗留的面部畸形得到改善。对于一些范围较小的局灶性病变,手术往往可以取得满意的效果;对于巨大、多发的血管瘤,手术治疗往往作用有限,常常为减瘤术。手术患者一般在术前均经过栓塞硬化治疗,这样可以大大减少术中出血。手术无法治愈脉管性疾病,是一种辅助 相似文献