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991.
Granulocyte-macrophage colony-stimulating factor and interleukin-3 mRNAs are produced by a small fraction of blood mononuclear cells 总被引:1,自引:0,他引:1
Wimperis JZ; Niemeyer CM; Sieff CA; Mathey-Prevot B; Nathan DG; Arceci RJ 《Blood》1989,74(5):1525-1530
Northern blot analysis has identified granulocyte macrophage colony stimulating factor (GM-CSF) mRNA in monocytes and both GM-CSF and interleukin-3 (IL-3) mRNA in lymphocytes. However, these results have not addressed whether all cells or a subset of the population is capable of hematopoietic growth factor (HGF) production. To resolve this question, we applied in situ hybridization of radiolabeled antisense RNA probes to centrifuged preparations of total blood mononuclear cells (BMCs) and fractionated lymphocyte subpopulations. Without stimulation, no circulating cells expressed detectable levels of GM-CSF or IL-3 mRNA. On stimulation of BMCs with phorbol myristate acetate (PMA) and phytohemagglutinin or PMA and the calcium ionophore ionomycin, approximately 5% expressed GM-CSF mRNA and approximately 1% IL-3 mRNA. Control sense probes produced no labeled cells. To determine the subsets of lymphocytes capable of GM-CSF and IL-3 expression, BMCs were fractionated by FACS into CD8+ and CD4+ lymphocyte subsets and CD16+ (NK) cells. The unfractionated cells and cell fractions were then stimulated with PMA and ionomycin. Results demonstrated that 3% to 5% of the CD16+, CD8+, and CD4+ lymphocytes produced GM-CSF mRNA. However, the number of IL-3 mRNA-positive cells in the FACS-sorted subsets was greatly reduced (0.02% to 0.05%) as compared with the unseparated cells (1%). Treatment of BMCs with high-dose interleukin-2 (IL-2) for 1 week followed by PMA plus ionomycin resulted in a lymphocyte population in which 50% and 3% of cells expressed GM-CSF and IL-3 mRNA, respectively. Thus, GM-CSF and IL-3 mRNA expression in T cells and NK cells is restricted to a small fraction of cells that can be greatly expanded by IL-2 stimulation. These results suggest a possible physiologic mechanism for increasing HGF production by circulating lymphocytes. 相似文献
992.
993.
994.
R Asirvatham H G Watts R J Rooney 《The Journal of bone and joint surgery. British volume》1990,72(3):409-411
After severe poliomyelitis, which is still relatively common in some developing countries, lateral rotation deformity of the tibia may occur. We have reviewed 51 patients treated by O'Donoghue's rotation osteotomy of the tibia. An average lateral rotation deformity of 57 degrees was fully corrected in all the patients, and in 38 of them the graft obtained during the osteotomy was used for a simultaneous Grice-Green subtalar arthrodesis in one or both feet. All the osteotomies united in an average of 11 weeks, some with relatively minor and unintentional posterior angulation. There was no posterior angulation when the length of the step cut osteotomy was 4.5 cm or more. O'Donoghue's osteotomy is a simple and safe operation, being particularly advantageous if a Grice-Green procedure is also required. 相似文献
995.
In a series of three consecutive pilot studies carried out between 1977 and 1981 at Wayne State University, Detroit, Michigan, designed to test the feasibility of multimodality therapy in patients with previously untreated advanced squamous cell carcinoma of the head and neck, patients received three different induction chemotherapy regimens: cisplatin + Oncovin (vincristine) + bleomycin (COB) for two courses; 96-hour 5-fluorouracil (5-FU) infusion and cisplatin for two courses, or 120-hour 5-FU infusion + cisplatin for three courses. Over-all response rates (complete response + partial response) to each of the three induction chemotherapy regimens were high: 80%, 88%, and 93%, respectively. Superior complete response rate in the group receiving three courses of 120-hour 5-FU infusion + cisplatin was 54% versus 29% for COB and 19% for two-course 96-hour 5-FU infusion + cisplatin (P = 0.04). Significant survival advantage at 18 months minimum follow-up for the group receiving three courses of 120-hour 5-FU + cisplatin induction therapy was found. Actual T and N stage may influence the clinical complete response rate. Responders to initial chemotherapy have significantly better survival as compared to nonresponders regardless of subsequent surgery and/or radiotherapy. These studies show that a multimodality approach to management of advanced head and neck cancer is feasible. Superior complete response rate and survival in one of the treatment groups suggest that choice of induction chemotherapy regimens and/or number of courses is of prime importance in such multimodality treatment programs. 相似文献
996.
A 1 MHz continuous wave sound field of intensity 0.6 W/cm2 was applied to a suspension of avian erythrocytes in vitro for 30 min. Sound induced alteration of membrane transport was tested by post treatment incubation of the insonated and control cells for 10 min. in labelled leucine. The total uptake (mediated transport plus diffusion and non-specific binding) was assayed by standard liquid scintillation counting procedures. The percentage of the total uptake due to mediated transport was determined by a similar incubation in a mixture of isoleucine/leucine (50:1, by mole). At the intensity used total uptake by sonated cells was approximately 5% less than by control cells. Analysis shows the effect, although small, to be statistically significant (p < 0.05). Similar analysis showed that the nonmediated component of transport was likewise diminished (p < 0.01). However, results for the effect of ultrasound on mediated transport are not statistically significant (p>0.9). 相似文献
997.
Edmundo B. Nery D.M.D. Kenneth L. Lynch Ph.D. George E. Rooney D.D.S. 《The Journal of prosthetic dentistry》1978,40(6):668-675
Tricalcium phosphate ceramic, with 50% porosity and 400 to 500 micrometer pore diameter, was used to augment the edentulous alveolar ridge of 10 adult mongrel dogs. The implants were evaluated histologically at different time intervals (7, 30, 90, 180, and 360 days). Preoperative and postoperative blood chemistry studies were also evaluated. The results showed that, other than for the expected acute nonspecific inflammatory response due to the surgery, the material was well tolerated by the tissues and was nontoxic. Bone and soft tissues grew into the pores, thereby creating an excellent biomechanical bond between the ceramic implant and surrounding structures. Preoperative and postoperative blood chemistry studies demonstrated no significant change. 相似文献
998.
999.
Graczykowski JW; Francis MM; Paulson RJ; Sokol RZ 《Human reproduction (Oxford, England)》1998,13(3):670-675
The zona pellucida binding assay assesses the ability of spermatozoa to
bind to the zona pellucida. The present study investigated the influence
of: (i) prior oocyte exposure to spermatozoa on subsequent sperm-zona
pellucida binding in vitro; and (ii) cryopreservation of oocytes. Only
oocytes obtained from fertile donors were used and the binding capacity of
non-inseminated, cryopreserved oocytes was compared with both
inseminated/unfertilized, cryopreserved oocytes and
inseminated/unfertilized, non-cryopreserved oocytes recovered from in-
vitro fertilization cultures on sperm-zona pellucida binding using an
intact zona model. There was no statistically significant difference in
sperm-zona binding between non-inseminated, cryopreserved oocytes (range
9.6-23.2), inseminated/unfertilized, cryopreserved oocytes (range
15.0-16.0) and inseminated/ unfertilized, non-cryopreserved oocytes (range
3.3-23.0). The coefficient of variation for sperm binding to all oocyte
groups was very large (range 37-121%). We conclude that neither prior
exposure of human oocytes to human spermatozoa nor cryopreservation of
human oocytes influences the subsequent binding of a different population
of spermatozoa to the zona pellucida. However, large oocyte-to-oocyte
variation of sperm-zona binding may diminish the usefulness of this assay
in clinical practice and as a research tool.
相似文献
1000.
应用荧光原位杂交技术分析乳糖不耐受者结肠菌群 总被引:3,自引:0,他引:3
目的 : 探讨结肠菌群构成与乳糖不耐受 (lactose intolerance,LI)症状之间的关系 ,以及饮奶对结肠双歧杆菌数量的影响。方法 : 根据乳糖负荷试验 ,结合问卷调查筛选成人乳糖吸收不良者、轻度及重度乳糖不耐受者作为试验对象。收集受试者一次新鲜全便 ,选用 5种特异性的 1 6S r RNA寡核苷酸探针 ,应用荧光原位杂交技术检测结肠细菌总数以及几种主要菌属 (种 )的构成。结果 : 乳糖不耐受组与吸收不良组相比 ,细菌总数和双歧杆菌数有显著性差异 (P<0 .0 5) ,细菌总数与乳糖不耐受症状评分之间呈负相关 (P<0 .0 5) ;每次饮奶以平均 2 0 0 ml计 5~ 7次 / w饮奶组与 0~ 2次 / w饮奶组或 0次 / w饮奶组相比 ,双歧杆菌数量显著增高 (P<0 .0 5)。结论 : 结肠细菌总数和双歧杆菌数可能与 LI症状的产生有关 ,同时饮奶习惯可能对双歧杆菌数量有潜在影响。 相似文献