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941.
942.
Invariant CD1d-restricted natural killer T (iNKT) cells function during innate and adaptive immune responses. A functional
and numerical deficiency of iNKT cells is well documented in both nonobese diabetic (NOD) mice and humans with autoimmune
type 1 diabetes (T1D). Restoring the numerical and/or functional deficiency of iNKT cells in NOD mice by either treatment
with α-galactosylceramide, transgenic induction of V α14-Jα18 expression, or transgenic expression of CD1d in NOD islets under
the control of the human insulin promoter confers protection from T1D in these mice. Recently, considerable progress has been
made in understanding the developmental and functional activities of iNKT cells. In this review, we discuss the role of iNKT
cell deficiency and defective development in the onset of T1D in NOD mice and the different protective mechanisms known to
restore these defects. 相似文献
943.
Akihiro Takemura Kenneth R. Hoffmann Masayuki Suzuki Zhou Wang Hussain S. Rangwala Hajime Harauchi Stephen Rudin Tokuo Umeda 《Journal of digital imaging》2008,21(1):99-108
Currently, a large number of endovascular interventions are performed for treatment of intracranial aneurysms. For these treatments,
correct positioning of microcatheter tips, microguide wire tips, or coils is essential. Techniques to detect such devices
may facilitate endovascular interventions. In this paper, we describe an algorithm for tracking of microcatheter tips during
fluoroscopically guided neuroendovascular interventions. A sequence of fluoroscopic images (1,024 × 1,024 × 12 bits) was acquired
using a C-arm angiography system as a microcatheter was passed through a carotid phantom which was on top of a head phantom.
The carotid phantom was a silicone cylinder containing a simulated vessel with the shape and curvatures of the internal carotid
artery. The head phantom consisted of a human skull and tissue-equivalent material. To detect the microcatheter in a given
fluoroscopic frame, a background image consisting of an average of the four previous frames is subtracted from the current
frame, the resulting image is filtered using a matched filter, and the position of maximum intensity in the filtered image
is taken as the catheter tip position in the current frame. The distance between the tracked position and the correct position
(error distance) was measured in each of the fluoroscopic images. The mean and standard deviation of the error distance values
were 0.277 mm (1.59 pixels) and 0.26 mm (1.5 pixels), respectively. The error distance was less than 3 pixels in the 93.0%
frames. Although the algorithm intermittently failed to correctly detect the catheter, the algorithm recovered the catheter
in subsequent frames. 相似文献
944.
Eberechukwu Onukwugha Candice Yong Michael Naslund Corinne Woods C. Daniel Mullins Brian Seal Arif Hussain 《Urologic oncology》2017,35(4):150.e17-150.e23
Background
The urologist generally manages the treatment of men immediately following the diagnosis of prostate cancer (PCa). The role of other physician specialists in this setting is less clear. We investigated whether involvement of other physician specialty types immediately following diagnosis affects initiation of cancer-directed treatment.Methods
This is a retrospective cohort study using linked cancer registry and claims data from 1999 to 2009, excluding stage I/II PCa. A physician visit index (PVI) served as the exposure variable and captured the “dispersion of care” across specialties, that is, the extent to which patient care involved different types of physician specialties such as the primary care physician, urologist, or oncologist. The PVI score was calculated using visits occurring within 30 days postdiagnosis. This score was dichotomized to measure “low PVI” (reflects seeing multiple specialist types). Competing risk Cox proportional hazard regression models provided adjusted hazard ratios (HR) for treatment receipt associated with a low PVI.Results
The sample included 33,380 patients: 4,910 metastatic and 28,470 nonmetastatic groups. The top 3 visit categories within 30 days postdiagnosis were “urologist only” (59%) and “urologist plus primary care physician” (21%) and no visit (6%). The median time to receipt of cancer-directed treatment was 51 days. Overall, 29% of individuals in the metastatic group and 38% in the nonmetastatic group were categorized as low PVI. A low PVI was associated with a shorter time to treatment receipt in the nonmetastatic (HR = 1.12 [95% CI: 1.09–1.15]) and metastatic (HR = 1.21 [95% CI: 1.14–1.29]) groups.Conclusions
Multispecialist involvement in the weeks following diagnosis is associated with a shorter time to treatment initiation, highlighting a role for exposure to different specialty types in the weeks following an initial diagnosis of PCa. This study provides important baseline data for future studies examining coordination of care across cancer and noncancer specialists. 相似文献945.
Jeffrey P. Carpenter Robert Cuff Clifford Buckley Christopher Healey Sajjad Hussain Michel M.P.J. Reijnen Jose Trani Dittmar Böckler 《Journal of vascular surgery》2017,65(2):330-336.e4
Objective
The Nellix EndoVascular Aneurysm Sealing (EVAS) System (Endologix, Inc, Irvine, Calif) is a novel approach to abdominal aortic aneurysm (AAA) treatment whereby polymer is used to fill the AAA sac. We report 1-year results of the investigational device exemption pivotal trial.Methods
Eligible patients were treated at 30 sites in the United States and Europe. Inclusion criteria required an asymptomatic infrarenal AAA, with a neck length ≥10 mm and ≤60° angle, iliac artery blood lumen diameter 9 to 35 mm, access artery diameter ≥6 mm, and serum creatinine ≤2 mg/dL. Follow-up included computed tomography angiography scans at 30 days, 6 months, and 1 year that were evaluated by a core laboratory. The primary safety end point was 30-day major adverse events (MAEs), which were compared with a performance goal of <56% (the Society for Vascular Surgery open repair control group rate). The primary effectiveness end point was treatment success at 1 year, which was compared with a performance goal of >80%. Treatment success required procedural technical success and absence of AAA rupture during follow-up, conversion to open surgical repair, endoleak (type I or III) at 1 year, migration >10 mm causing complications or requiring secondary intervention, aneurysm enlargement, or secondary procedures through 1 year for resolution of endoleak, device obstruction or occlusion, or device defect.Results
Of 150 treated patients, 149 (99.3%) completed 1-year follow-up. The MAEs rate at 30 days was 2.7% (95% confidence interval, 0.7%-6.7%), satisfying the primary safety end point (<56%). The 1-year treatment success was 94% (95% confidence interval, 88.6%-97.4%), achieving the primary effectiveness end point (>80%). At 1 year, key secondary outcomes included 6.7% MAEs, 4.7% serious device-related events, 1.3% AAA-related mortality, 3.7% secondary interventions, and 0.7% surgical conversions. MAEs through 1 year included death (n = 6), stroke (n = 3), bowel ischemia (n = 2), renal failure (n = 2), respiratory failure (n = 2), and myocardial infarction (n =1). One iatrogenic AAA rupture occurred and one AAA rupture was reported during follow-up. AAA sac enlargement (>5 mm) was 1.5% at 1 year. Endoleaks were present in four patients (3.1%) at 1 year (1 type Ib and 3 type II). Migration >10 mm occurred in three patients (2.3%), but none required secondary intervention.Conclusions
Outcomes with this novel endovascular therapy for AAA, the Nellix EVAS System, are encouraging. The primary safety and effectiveness end points have been met. Low morbidity, low mortality, and high procedural and treatment success were achieved despite the inevitability of a learning curve and unique risks associated with a new device and technique. Long-term follow-up is in progress. 相似文献946.
Rikke Løvendahl Eefsen Jim S. Larsen Louise L. Klarskov Rahim Altaf Estrid Høgdall Peter Ingeholm Jakob Lykke Dorte L. Nielsen Per Pfeiffer Laurids Ø. Poulsen Camilla Qvortrup Jakob V. Schou Morten Mau-Sørensen Kell Østerlind Benny V. Jensen 《International journal of cancer. Journal international du cancer》2023,152(10):2145-2152
Therapy with immune checkpoint inhibitors (ICI) is effective in patients with metastatic mismatch-repair deficient (dMMR) colorectal cancer (CRC); however, data on treatment with neoadjuvant ICI in patients with locally advanced CRC are limited. From March 2019 to June 2020, five Danish oncological centers treated 10 patients with a treatment-naïve dMMR CRC with preoperative pembrolizumab, 9 with a nonmetastatic, unresectable colon cancer and 1 with a locally advanced rectum cancer. All 10 patients were evaluated regularly at a multidisciplinary team (MDT) meeting, and they all had a radical resection after a median of 8 cycles (range 2-13) of pembrolizumab. A microscopic evaluation of the resected tumors revealed no remaining tumor cells in five patients, while five still had tumor cells present. The patients were given no additional therapy. No recurrences were reported after a median follow-up of 26 months (range 23-38.5 months). Biopsies from Danish patients with CRC are routinely screened for dMMR proteins. In 2017, data from the Danish Colorectal Cancer Group showed that 19% (565/3000) of the patients with colon cancer and 1.5% (19/1279) of those with rectum cancer had an dMMR tumor. Among the patients with MMR determination, 26% (99/384) patients had a T4 dMMR colon cancer; thus, the 10 patients treated with neoadjuvant pembrolizumab comprised about 9% of the patients with a T4 dMMR colon cancer (9/99) and 5% of patients with dMMR rectal cancer (1/19). Therapy with pembrolizumab was feasible and effective. Larger prospective trials are needed to confirm our findings. 相似文献
947.
948.
Bhogal Rashmeet Hussain Abid Balaji Ariyur Bermingham William H. Marriott John F. Krishna Mamidipudi T. 《International journal of clinical pharmacy》2021,43(3):461-475
International Journal of Clinical Pharmacy - Background A label of penicillin allergy is held by 6–10% of the general population and 15–20% of inpatients.?>?90% of... 相似文献
949.
950.
Ferulic (FA) and p-hydroxybenzoic acid (pHBA) are commonly found as phenolic compounds (PHC) in many forage and cereal crops. Although the effects of these PHC on seedling growth are relatively explored, not many information is available regarding the phytotoxicity on ecophysiological processes of perennial ryegrass adult plants. The experiment was conducted with the aim to evaluate the phytotoxic potential of PHC on the seedling growth, leaf water relation, chlorophyll fluorescence attributes and carbon isotope discrimination adult plants of perennial ryegrass (Lolium perenne L.). The results clearly indicated that PHC behaved as potent inhibitors of chlorophyll fluorescence yield (Fv/Fm) in leaves of L. perenne and plants showed poor tolerance against allelochemicals stress. Quantum yield (ΦPSII), chlorophyll fluorescence quenching (qP) and non-photochemical quenching (NPQ) were decreased following exposure to FA and pHBA. The portion of absorbed photon energy that was thermally dissipated (D) in L. perenne was decreased. Exposure of the L. perenne seedlings to FA and pHBA stress led to a decrease in fresh/dry weight, relative water content and leaf osmotic potential. Carbon isotope composition ratio (δ13C) was significantly less negative than the control following treatment with FA or pHBA. The results suggested that PHC uptake was a key step for the effectiveness of these secondary metabolites and their phytotoxicity on L. perenne adult plants was mainly due to the alteration of leaf water status accompanied by photosystem II damage. Acquisition of such knowledge may ultimately provide a better understanding about the mode of action of the tested compounds. 相似文献