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排序方式: 共有912条查询结果,搜索用时 31 毫秒
61.
Radiologically guided balloon catheters were used to dilate 94 gastrointestinal strictures in 92 patients over a 6-year period. Fifty strictures were esophageal and 44 nonesophageal (22 gastroenterostomies, 11 antral-pyloric strictures, four colorectal strictures, four enteroenterostomies, and three miscellaneous strictures). Factors influencing the success of stricture intubation included patient age, stricture location (esophageal vs. nonesophageal and proximal vs. distal esophageal), and association with a surgical anastomosis. Malignancy was associated with greater postdilation irregularity and a smaller increase in stricture diameter, as measured radiographically. Procedural failures occurred in 8% of cases (2% of esophageal and 30% of nonesophageal lesions). Two small, asymptomatic mucosal tears were seen after dilation (one esophageal and one colonic); no other procedural complications occurred. Following successful dilation, 16 patients (17%; six with esophageal and ten with non-esophageal strictures) had recurrence of symptoms during short-term (30-day) follow-up. 相似文献
62.
Data obtained on 426 consecutive patients referred to a breast center by 122 physicians, including family practitioners, general surgeons, and other specialists, showed that the obstetricians-gynecologists referred the greatest average number of patients per physician, with more than 50% of these referrals for screening mammography. Internists referred fewer patients by nearly a factor of ten, with only one-third of these patients referred for screening mammography. Internists may be the weakest link in the utilization of screening mammography. 相似文献
63.
64.
Different materials have been studied in order to produce the epithermal neutron beam between 1eV and 10KeV, which are extensively used to irradiate patients with brain tumors such as GBM. For this purpose, we have studied three different neutrons moderators (H(2)O, D(2)O and BeO) and their combinations, four reflectors (Al(2)O(3), C, Bi, and Pb) and two filters (Cd and Bi). Results of calculation showed that the best obtained assembly configuration corresponds to the combination of the three moderators H(2)O, BeO and D(2)O jointly to Al(2)O(3) reflector and two filter Cd+Bi optimize the spectrum of the epithermal neutron at 72%, and minimize the thermal neutron to 4% and thus it can be used to treat the deep tumor brain. The calculations have been performed by means of the Monte Carlo N (particle code MCNP 5C). Our results strongly encourage further studying of irradiation of the head with epithermal neutron fields. 相似文献
65.
Autoantibodies against bactericidal/permeability-increasing protein in patients with cystic fibrosis 总被引:5,自引:0,他引:5
Zhao MH; Jayne DR; Ardiles LG; Culley F; Hodson ME; Lockwood CM 《QJM : monthly journal of the Association of Physicians》1996,89(4):259-265
Cystic fibrosis (CF), a genetic disorder, is characterized by chronic
pulmonary infection/inflammation which leads to respiratory failure. The
presence of anti-neutrophil cytoplasmic autoantibodies (ANCA) has
previously been observed in the sera of patients with CF. In view of the
known relationship of ANCA with primary vasculitis and of their putative
pathogenetic role in these disorders, we studied the presence, specificity
and isotype of ANCA and their clinical associations in 66 adult CF
patients. None of the 66 CF samples had autoantibodies to the major ANCA
antigens, proteinase 3 or myeloperoxidase. However, 60/66 (91%) CF samples
contained IgG and 55/66 (83%) IgA, autoantibodies to
bactericidal/permeability increasing protein (BPI), a recently
characterized ANCA specificity. All the IgA anti-BPI-positive samples were
also IgG anti-BPI-positive. The autoantibody specificity was confirmed by
inhibition assay and immunoblotting of CF sera against a neutrophil granule
preparation. Furthermore, in this cross-sectional study, anti-BPI levels
were inversely correlated with the observed reductions in FEV1 and FVC (IgA
anti-BPI and FEV1: r = 0.508, <it>p</it> < 0.0001), and
both IgG and IgA anti-BPI levels were higher in CF patients with secondary
vasculitis (<it>n</it> = 6) than in those without
(<it>p</it> < 0.05). ANCA with specificity for BPI were
present in the majority of CF sera in this study and autoimmune processes
may be associated with the development of pulmonary injury in CF.
相似文献
66.
Stanworth SJ; Bhavnani M; Chattopadhya C; Miller H; Swinson DR 《QJM : monthly journal of the Association of Physicians》1998,91(1):49-56
Felty's syndrome (FS) (rheumatoid arthritis with neutropenia and
splenomegaly) has a poor prognosis, largely because of the high risk of
severe infection. Granulocyte colony-stimulating factor (G-CSF) is an
emerging treatment for chronic neutropenia. We prospectively monitored its
use in eight patients with recurrent infections or who required joint
surgery. Significant side-effects were documented in five, including
nausea, malaise, generalized joint pains, and in one patient, a vasculitic
skin rash. In two patients treatment had to be stopped, and in these cases
G-CSF had been started at full vial dosage (300 micrograms/ml filgrastim or
263 micrograms/ml lenograstim) alternate days or daily. G-CSF treatment was
continued in three patients by restarting at reduced dose, and changing the
proprietary formulation. G- CSF raised the neutrophil count, reduced severe
infection, and allowed surgery to be performed. A combined clinical and
laboratory index suggested that long-term treatment (up to 3.5 years) did
not exacerbate the arthritis. Once on established treatment, it may be
possible to use smaller weekly doses of G-CSF to maintain the same clinical
benefit. One of the three patients whose FS was associated with a large
granular T-cell lymphocytosis showed a reduction in this subset of
lymphocytes during G-CSF treatment.
相似文献
67.
The effect of sterilization on transforming growth factor beta isolated from demineralized human bone 总被引:1,自引:0,他引:1
Growth factors have been identified as the primary cause of osteoinduction in bone healing. Transforming growth factor beta (TGF- beta) has been shown to promote bone formation and is present in bone in high quantities. The aims of the present study were to isolate TGF- beta from human bone, demonstrate its biologic activity, and analyze the effects of conventional sterilization techniques on activity. Bone, obtained from femoral heads of five patients (mean age, 70 years) was ground, demineralized, and freeze-dried, and samples from each patient were divided into three groups: no treatment, sterilization with 1.60 to 1.94 Mrad of 60Co irradiation, and sterilization with ethylene oxide (ETO). Carrier-free recombinant TGF-beta control was also treated and was totally inactivated by ETO but not by irradiation (p < 0.01). TGF- beta activity in demineralized bone was not significantly diminished (p > 0.1) by either sterilization procedure, and substantial amounts of active TGF-beta were recovered in all bone samples: 1.04 +/− 0.77 ng per mg of protein in irradiated samples, 0.67 +/− 0.26 ng per mg in ETO- treated samples, and 1.04 +/− 0.33 in untreated samples, respectively (mean +/− SD). Although a recent report demonstrated that the osteoinductive activity of bone morphogenetic protein in bone powder is diminished considerably by ETO and by 2.5 Mrad of irradiation sterilization of bone powder, these data demonstrate that TGF-beta activity, with its osteoinductive properties, was not destroyed in more coarsely ground, demineralized bone by ETO or by lower doses of irradiation. These findings support the use of human bone allografts in clinical instances involving impaired bone formation. 相似文献
68.
David Galloway Ethan Mezoff Wujuan Zhang Melissa Byrd Conrad Cole Inmaculada Aban Samuel Kocoshis Kenneth DR Setchell James E Heubi 《JPEN. Journal of parenteral and enteral nutrition》2019,43(2):263-270
Background: We determined qualitative and quantitative serum unconjugated bile acid (SUBA) levels among children with history of intestinal failure (IF) and suspected small bowel bacterial overgrowth (SBBO). Methods: This was a single‐center, case‐control pilot study conducted at Cincinnati Children's Hospital Medical Center. Children with history of IF and suspected SBBO were enrolled as subjects. Age‐matched children without IF or suspected SBBO served as controls. All participants underwent small bowel fluid sampling for microbial culture analysis. Additionally, serum fractionated and total bile acids were measured by liquid chromatography‐mass spectrometry at enrollment and following treatment for SBBO. Results: SUBA concentrations were elevated in IF subjects (median 1.16 μM, range 0.43–10.65 μM) compared with controls (median 0.10 μM, range 0.05–0.18 μM, P = 0.001). Among SUBA, chenodeoxycholic acid (CDCA) was significantly elevated in subjects (median 0.8 μM, range 0–7.08 μM) compared with controls (median 0 μM, range 0–0.03 μM, P = 0.012). When controls were excluded from analysis, IF subjects with positive aspirates for SBBO demonstrated higher concentration of CDCA (median 7.36 μM, range 1.1–8.28 μM) compared with IF subjects with negative aspirates (median 0.18 μM, range 0–1.06 μM, P = 0.017). Treatment for SBBO did not alter SUBA concentration. Conclusions: SUBA concentrations are elevated in children with history of IF and presumed SBBO compared with non‐IF controls. CDCA was more prevalent in IF subjects with positive aspirates for SBBO compared with IF subjects with negative aspirates. The determination of SUBA concentration may be a useful surrogate to small bowel fluid aspiration in the diagnosis of SBBO in children with history of IF. 相似文献
69.
白介素与溃疡性结肠炎 总被引:17,自引:1,他引:17
近年来对白介素(interleukin,IL)和溃疡性结肠炎(ulcerative colitis,UC)的研究取得了很大进展,我们通过总结整理以前有关IL和UC的文献,概括出IL的产生和在UC发病及病理变化中的作用机制:IL-1直接介导了UC初期阶段炎症的发生:IL-8、IL-6直接促进炎性细胞过度分泌和/或抑制了炎性细胞的凋亡,IL-2分泌减少导致免疫系统内细胞间网络调节失衡, 使局部炎症介质和自由基释放,引起细胞毒作用,IL主要通过影响机体整体和/或局部免疫系统的功能介导UC的产生,并与UC的迁延难愈和反复发作有关. 相似文献
70.
H Boralessa DR Goldhill K Tucker AJ Mortimer J Grant-Casey 《Annals of the Royal College of Surgeons of England》2009,91(7):599-605