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31.
OBJECTIVE: Computed tomographic screening is detecting ever smaller peripheral non-small cell lung cancers. These smaller cancers are amenable to sublobar resection, but sublobar resection is not currently the treatment of choice. This study compared sublobar resection with lobar resection for stage IA non-small cell lung cancers to assess whether sublobar resection is appropriate treatment for certain lesions. The use of adjuvant brachytherapy was also evaluated. METHODS: A retrospective multicenter study of 291 patients with T1 N0 disease was done. Outcomes after sublobar resection (n = 124) were compared with those after lobar resection (n = 167). Brachytherapy was used in conjunction with 60 (48%) sublobar resection operations. Analysis based on tumor diameter was performed. RESULTS: There were 137 cancers smaller than 2 cm and 154 cancers ranging from 2 to 3 cm. Patients undergoing sublobar resection were older (68.4 vs 66.1 years, P = .018) with poorer pulmonary function (forced expiratory volume in 1 second of 53.1% vs 78.2%, P = .001). Mean follow-up was 34.5 months. Brachytherapy decreased local recurrence rate significantly among patients undergoing sublobar resection, from 11 (17.2%) to 2 (3.3%). For tumors smaller than 2 cm, there was no difference in survival between sublobar resection and lobar resection groups. For the larger tumors (2-3 cm), median survival was significantly better in the lobar resection group, at 70 versus 44.7 months ( P = .003). CONCLUSION: Intraoperative brachytherapy may reduce the local recurrence that is usually reported with sublobar resection. Our experience supports the further investigation of the use of sublobar resection with brachytherapy for peripheral stage IA non-small cell lung cancers smaller than 2 cm.  相似文献   
32.
Boufous S  Finch C  Lord S  Close J 《Injury》2005,36(11):1323-1329
Despite their significant health burden, epidemiological information regarding pelvic fractures is scarce. In this study, we examine trends in admission for pelvic fractures to acute hospitals in New South Wales, Australia, between July 1988 and June 2000, using routinely collected hospital separations statistics. Over this period, the number of admissions for pelvic fractures among those aged 50 years and over increased by 58.4% in men and 110.8% in women. Age-specific rates of admissions per 100,000 population for pelvic fracture also rose significantly, particularly for those aged at least 75 years. The number and proportion of transport related pelvic fractures fell significantly for both men (chi(2)=23.82, d.f.=1, p<0.001) and women (chi(2)=49.26, d.f.=1, p<0.001) while those resulting from falls increased significantly over the 12-year-period. Falls are increasingly becoming the single most important cause of pelvic injuries in older people, suggesting that preventive measures aimed at reducing the risk of falls need to be pursued. Factors contributing to the rise of fall-related pelvic fractures need to be investigated to inform strategies aimed at reversing the observed increase in the number and age-specific rates of pelvic fractures in older people.  相似文献   
33.
Mitropoulos  KA; Martin  JC; Reeves  BE; Esnouf  MP 《Blood》1989,73(6):1525-1533
The endogenous, negatively charged surface that induces activation of the contact coagulation factors was investigated in plasmas taken from women in late pregnancy and control subjects of child-bearing age. The plasmas from the two groups of subjects were incubated at 4 degrees C for 24 hours either in plastic or in glass tubes and the factor VII coagulant activity (VIIc) was assayed in the treated plasmas. The activation of factor VII under these conditions involves the generation of enzymes derived from factor XII (XIIa). The contact surface is rate- limiting for the activation of factor VII in the plasmas in both groups of subjects and can be supplemented by large multilamellar liposomal vesicles carrying the appropriate density of negative charge. The size of these vesicles is within the range of sizes of the large lipoprotein particles (chylomicrons, very low and intermediate-density lipoproteins). The relationship between the density of negative charge on the liposomal vesicles and VIIc was similar in the late pregnancy and the control plasmas incubated in plastic tubes. At a saturating density of negative charge the observed relative VIIc was similar in both sets of plasmas. The incubation of late pregnancy or control plasma in plastic tubes in the presence of sodium stearate caused VIIc to increase with increasing concentration of the added fatty acid. These results suggest that large lipoprotein particles carrying the appropriate free fatty acid at a sufficient density of negative charge could provide the contact surface that induces the generation of factor XIIa and the subsequent activation of factor VII. Moreover, plasmas from women in late pregnancy have a higher concentration of potential surface and a higher density of negative charge than the plasmas from nonpregnant women.  相似文献   
34.
直到最近为止,冠心病的内科治疗原则仍是降低心肌需氧量。由于粥样硬化病变一直认为是固定不变的狭窄,不可能增加冠脉血流量,因此认为用药物扩张冠状动脉是徒劳的。在近几年内这些概念有了基本转变。然而仅能引起远端心肌内小动脉扩张的药物却起着相反的作用。当心外膜冠状动脉有粥样硬化时,冠状小动脉扩张可加重血流分布异常,导致心肌缺血。冠状循环由近端大冠状动脉及其分枝小动脉组成的心肌内动脉网构成。近端大冠状  相似文献   
35.
Medullary carcinoma of the breast: mammographic and US appearance   总被引:4,自引:0,他引:4  
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36.
37.
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   
38.
39.
Young  JC; Bruno  E; Luens  KM; Wu  S; Backer  M; Murray  LJ 《Blood》1996,88(5):1619-1631
Thrombopoietin (TPO) or MpI ligand is known to stimulate megakaryocyte (MK) proliferation and differentiation. To identify the earliest human hematopoietic cells on which TPO acts, we cultured single CD34+Thy- 1+Lin- adult bone marrow cells in the presence of TPO alone, with TPO and interleukin-3 (IL-3), or with TPO and c-kit ligand (KL) in the presence of a murine stromal cell line (Sys1). Two distinct growth morphologies were observed: expansion of up to 200 blast cells with subsequent differentiation to large refractile CD41b+ MKs within 3 weeks or expansion to 200-10,000 blast cells, up to 25% of which expressed CD34. The latter blast cell expansions occurred over a 3- to 6-week period without obvious MK differentiation. Morphological staining, analysis of surface marker expression, and colony formation analysis revealed that these populations consisted predominantly of cells committed to the myelomonocytic lineage. The addition of IL-3 to TPO-containing cultures increased the extent of proliferation of single cells, whereas addition of KL increased the percentage of CD34+ cells among the expanding cell populations. Production of multiple colony- forming unit-MK from single CD34+Thy-1+Lin- cells in the presence of TPO was also demonstrated. In limiting dilution assays of CD34+Lin- cells, TPO was found to increase the size and frequency of cobblestone areas at 4 weeks in stromal cultures in the presence of leukemia inhibitory factor and IL-6. In stroma-free cultures, TPO activated a quiescent CD34+Lin-Rhodamine 123lo subset of primitive hematopoietic progenitor cells into cycle, without loss of CD34 expression. These data demonstrate that TPO acts directly on and supports division of cells more primitive than those committed to the MK lineage.  相似文献   
40.
Objective:To investigate the wound healing properly of Napoleona vogelii leaf extract in folkloric medicine.Methods:Roth sexes of adult albino rats(n=25) were used in this study and another group(n=30) were subjected to acute toxicity test(LD_(50)) of the plant extract.For the LD_(50),three randomized groups of 5 rats were first treated with 10,100,1 000 mg/kg body weight(bw),orally.This w as followed by a second treatment of 1500,3000,and 5 000 mg/kg bw of the leaf extract with continual monitoring of the animals for mortality or non-mortality.Incision wounds(1.3cm) were created on the skin of five groups of 5 rals using surgical blade under anesthesia.The first group was topically treated with petroleum jelly alone,group 2 was topically applied 400 mg/mL w/v of the reference drug,Neobaein,while group 3-5 were topically treated with 5-50 mg/mL w/v of the plant extract,respectively.Results:The percentage yield of the extract was 49.80%w/w dry matter.The phytochemical analysis revealed several bioactive constituents including glycosides,tannins,alkaloids,perpenoids.saponins,steroids,proteins,and carbohydrates.The LD_(50) was beyond our experimental limit and was not determined.Increased concentrations(5,20,and 50mg/mL w/v) of the extract had significant(ANOVA,P0.05) healing effect on the incision wounds giving rise to 125%-140% while treatmentawith Neobacin resulted in 150% healing effect on the third treatment regimen compared to the control(100%).Conclusions:These data indicate that Napoleona vogelii leaf extract contains potent bioactive compounds containing wound healing activity,substantiating its use as a wound healer in folkloric medicine.  相似文献   
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