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排序方式: 共有1747条查询结果,搜索用时 31 毫秒
1.
John P Elliott Hugh S Miller Suzanne Coleman Debbie Rhea Diana Abril Karen Hallbauer Niki B Istwan Gary J Stanziano 《Journal of perinatology》2005,25(10):626-630
OBJECTIVE: To assess the impact of activity restriction (AR) on the incidence of preterm birth in women treated for preterm labor testing negative for fetal fibronectin (fFN). STUDY DESIGN: Women who were diagnosed with preterm labor and tocolyzed with magnesium sulfate were concurrently screened with fFN for the purpose of subsequent management. Included were consenting patients with negative fFN, gestational age 23 0/7-33 6/7 weeks, cervical dilation < or =3 cm, and minimal vaginal bleeding. Patients were randomized to AR or no AR. Primary study outcome was incidence of preterm delivery and interval from randomization to delivery. RESULTS: A total of 73 women with negative fFN were randomized (36 with AR, 37 without AR). The overall preterm birth rate was 40%, with 44.4% of patients with AR and 35.1% of patients without AR delivering preterm, p=0.478. CONCLUSION: Maternal AR did not impact pregnancy outcome. The incidence of preterm birth in symptomatic women testing fFN negative was higher than previously reported. 相似文献
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3.
Masaki Hata Akinori Nango Hisateru Niki Yoshifumi Hayafune Atsushi Kato 《Journal of orthopaedic science》1997,2(1):3-9
To elucidate the growth of the tarsal bones in congenital clubfoot, relative to the growth of these bones in the unaffected feet and compared to growth in the feet of normal volunteers, we used a computed tomography (CT) scanner to measure the volume of all tarsal bones. The subjects of the study were 10 adults (7 men and 3 women) with unilateral congenital clubfoot (average age 20 years and 1 month). As controls, we examined 11 healthy volunteers. We calculated the ratio of the volume of each tarsal bone to the total bone volume and the ratio of the volume of each tarsal bone in clubfoot to the corresponding bone in the unaffected foot. The volume ratio of each tarsal bone was compared between clubfeet and unaffected feet because the differences of each tarsal bone ratio between the normal foot group and unaffected foot group were not significant. In the clubfeet (n=10), the talus and the medial cuneiform bones were smaller than those in the unaffected feet (n=10) but the cuboid bone was larger. The growth of the navicular did not differ from as that in unaffected feet. Our results suggested hypoplasia on the medial side of the foot in adult patients with congenital clubfoot. The 3 patients who had undergone medial release showed particularly marked hypoplasia of the medial side. In congenital clubfoot cases with severe deformities who had undergone wide soft-tissue release operations, there were clear growth suppressions in the talus and the medial cuneiform. We could not determine whether the cause of the growth suppression was the hypoplastic nature of tarsal bones themselves or the surgical obstacles to tarsal bone growth. 相似文献
4.
John P Elliott Niki B Istwan Ann Collins Debbie Rhea Gary Stanziano 《Journal of perinatology》2005,25(1):4-7
OBJECTIVE: To identify the etiology and impact of preterm delivery in twin gestations. STUDY DESIGN: Twin gestations delivered at 33.0 to 36.9 weeks were identified in a perinatal database, and categorized by indication for delivery. Deliveries were identified as indicated, or non-indicated (discretionary). Neonatal outcomes were measured by birth weight, length of stay, NICU admission, and ventilator utilization. Data were divided and analyzed by indicated or discretionary delivery, and gestational age at delivery. RESULTS: Analyzed were 3252 twin gestations (6504 infants), with 78% having indicated delivery. Of the 22% with discretionary delivery, nearly 40% required NICU admission. With each advancing week of gestation, there was a significant decrease in incidence of NICU admission and nursery days. CONCLUSION: The majority of preterm deliveries were indicated, though 22% were discretionary. It is vital to consider neonatal morbidity and costs related to gestational age when choosing discretionary delivery. 相似文献
5.
Summary The effects of the and anomers of D-glucose on insulin release were studied in a rat model of non-insulin-dependent diabetes, which was induced by streptozotocin injection at 2 days of age. Glucose tolerance of the streptozotocin-treated rats at 8–10 weeks of age was mildly diabetic. Insulin release from the isolated perfused pancreas of the diabetic rats in response to 10 mmol/l -D-glucose was markedly impaired, while insulin response to 10 mmol/l -D-glucose in the diabetic pancreas was only slightly reduced as compared to that in the control pancreas. 相似文献
6.
Dimitri A. Adamopoulos M.D. Sophia Kampyli M.D. Fotis Georgiacodis Ph.D. Niki Kapolla B.Sc. Anahit Abrahamian-Michalakis M.D. 《Archives of sexual behavior》1988,17(5):421-429
Sexual activity was evaluated in 51 women with hirsutism associated with increased levels of circulating androgens before and while on combined treatment with the antiandrogen cyproterone acetate (CA) and ethinyl estradiol (EE2) and compared to a reference group of 52 subjects. The percentage of unbound testosterone (T) was higher (p < 0.001), the coital frequency lower (p < 0.05), and the masturbation frequency higher (p< 0.04) in hirsute women. Mean frequency of total activity (coitus plus masturbation) was similar in the two groups. Treatment with combination of CA and EE2 resulted in a decline of unbound T (p< 0.001). There was no change of total sexual activity, but coital frequency increased (p < 0.05) and masturbation frequency declined (p < 0.04). It is concluded that raised levels of circulating androgens, as judged by free T concentration, are not of crucial importance in the expression of sexual behavior in hirsute women. 相似文献
7.
Metal ions induce bone-resorbing cytokine production through the redox pathway in synoviocytes and bone marrow macrophages 总被引:6,自引:0,他引:6
Niki Y Matsumoto H Suda Y Otani T Fujikawa K Toyama Y Hisamori N Nozue A 《Biomaterials》2003,24(8):1447-1457
To evaluate the biological reactions to metal ions potentially released from prosthetic implants, we examined the ability of metal ions to produce bone-resorbing cytokines and the underlying mechanism using synoviocytes and bone marrow (BM) macrophages. The cells were incubated with NiCl(2), CoCl(2), CrCl(3) or Fe(2)(SO(4))(3) at optimal concentrations, which are detectable in joint fluid following total joint arthroplasty. The production of interleukin-1beta, interleukin-6 and tumor necrosis factor-alpha were enhanced by all metal ions tested as determined by enzyme-linked immunosorbent assay. From the results of electrophoresis mobility shift assay, all metal ions enhanced the DNA-binding activity of nuclear factor kappaB (NF-kappaB), and p50-p65 heterodimers and p50 homodimers were the major subunits. These effects of the metal ions were considerably blocked by pyrrolidine dithiocarbamate (PDTC) known as a radical scavenger. An electron spin resonance study clearly demonstrated the ability of metal ions to generate activated oxygen species (AOS), especially hydroxyl radicals (*OH), which accounts for PDTC-blockade of metal ion-induced NF-kappaB activation and subsequent cytokine production. Taken together, our data raised the possibility that small amounts of metal ions released from prosthetic implants activate synoviocytes and BM macrophages through the AOS-mediated process (i.e. the redox pathway), and contribute to the initiation of osteolysis at the bone-implant interface. 相似文献
8.
Vladimir Ivancev Ivan Palada Zoran Valic Ante Obad Darija Bakovic Niki M. Dietz Michael J. Joyner Zeljko Dujic 《The Journal of physiology》2007,582(2):723-730
Hypercapnic cerebrovascular reactivity is decreased in obstructive sleep apnoea and congestive heart disease perhaps as a result of repeated apnoeas. To test the hypothesis that repeated apnoeas blunt cerebrovascular reactivity to hypercapnia, we studied breath hold divers and determined cerebrovascular reactivity by measuring changes in middle cerebral artery velocity (MCAV, cm s−1 ) per mmHg change in end-tidal partial pressure of CO2 ( ) in response to two hyperoxic hypercapnia rebreathing manoeuvres (modified Read protocol) in elite breath-hold divers (BHD, n = 7) and non-divers (ND, n = 7). In addition, ventilation and central (beat-to-beat stroke volume measurement with Modelflow technique) haemodynamics were determined. Ventilatory responses to hypercapnia were blunted in BHD versus ND largely due to lower breathing frequency. Cerebrovascular reactivity did not differ between groups (3.7 ± 1.4 versus 3.4 ± 1.3% mmHg−1 in BHD and ND, respectively; P = 0.90) and the same was found for cerebral vascular resistance and MCAV recovery to baseline after termination of the CO2 challenge. Cardiovascular parameters were not changed significantly during rebreathing in either group, except for a small increase in mean arterial pressure for both groups. Our findings indicate that the regulation of the cerebral circulation in response to hypercapnia is intact in elite breath-hold divers, potentially as a protective mechanism against the chronic intermittent cerebral hypoxia and/or hypercapnia that occurs during breath-hold diving. These data also suggest that factors other than repeated apnoeas contribute to the blunting of cerebrovascular reactivity in conditions like sleep apnoea. 相似文献
9.
Panagiota Lambrou Eleftherios Zervas Erasmia Oikonomidou Niki Papageorgiou Manos Alchanatis Mina Gaga 《Annals of allergy, asthma & immunology》2007,98(6):567-572
BACKGROUND: Asthma and rhinitis often coexist, and there is evidence to suggest that they have similar histopathologic features. OBJECTIVE: To examine whether the inflammatory infiltration in the nasal mucosa in rhinitis is affected by the presence of asthma and allergy. METHODS: Nasal mucosa biopsy samples were collected from 44 individuals: 18 with rhinitis and asthma (9 allergic and 9 nonallergic), 16 with rhinitis and no asthma (8 allergic and 8 nonallergic), and 10 nonallergic control subjects. The alkaline phosphatase-anti-alkaline phosphatase method was applied to 6-microm-thick cryostat sections using monoclonal antibodies against T cells (CD4 and CD8) and eosinophils (EG2). Slides were counted blindly, and results are expressed as cells per high-power field. RESULTS: Eosinophil counts were higher in the nasal mucosa of rhinitic patients vs controls. No differences in cellular infiltration were detected between rhinitic patients with and without asthma or between allergic and nonallergic patients. A trend toward higher CD4+ T-cell counts in the nasal mucosa of rhinitic patients was observed, whereas no differences were noted in CD8+ T-cell infiltration among the groups. CONCLUSION: Inflammatory infiltration, characterized by the presence of eosinophils and CD4+ T cells, was similar in the nasal mucosa in noninfectious rhinitis irrespective of the presence of asthma or the allergic status of the patient. 相似文献
10.
Use of immunoblotting to detect Aspergillus fumigatus antigen in sera and urines of rats with experimental invasive aspergillosis. 总被引:5,自引:2,他引:5 下载免费PDF全文
Immunoblotting was used to detect Aspergillus fumigatus antigen in sera and urines of immunosuppressed rats experimentally infected with A. fumigatus. Organisms were administered by both intravenous and intratracheal injections. Intravenously infected rats developed disseminated aspergillosis, but intratracheally infected rats developed pulmonary disease only. Fungal cultures of blood and urine samples from infected rats were negative. In the urines of intravenously infected rats, antigen was detected 24 to 48 h after infection; in the urines of intratracheally infected animals, antigen was detected on days 4 to 5 after infection. Antigen in serum was detected later than antigen in urine was. Following sodium dodecyl sulfate-polyacrylamide gel electrophoresis and immunoblotting of serum and urine samples, the most strongly reacting antigenic materials were found in the 88-, 40-, 27-, and 20-kilodalton regions. These dominant antigens appeared to be the same as those of control antigens prepared from A. fumigatus grown in vitro. Rabbit antiserum to Aspergillus filtrate antigen was found to be more immunoreactive than antiserum to mycelial or conidial antigen. No mycelium-specific antigens were detected. 相似文献