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排序方式: 共有1124条查询结果,搜索用时 15 毫秒
51.
52.
Cong Yu Hui Yin Tan Meerim Choi Adam J. Stanenas Alicia K. Byrd Kevin D. Raney Christopher S. Cohan Piero R. Bianco 《Genes to cells : devoted to molecular & cellular mechanisms》2016,21(2):163-184
The E. coli single‐stranded DNA‐binding protein (SSB) binds to the fork DNA helicases RecG and PriA in vitro. Typically for binding to occur, 1.3 m ammonium sulfate must be present, bringing into question the validity of these results as these are nonphysiological conditions. To determine whether SSB can bind to these helicases, we examined binding in vivo. First, using fluorescence microscopy, we show that SSB localizes PriA and RecG to the vicinity of the inner membrane in the absence of DNA damage. Localization requires that SSB be in excess over the DNA helicases and the SSB C‐terminus and both PriA and RecG be present. Second, using the purification of tagged complexes, our results show that SSB binds to PriA and RecG in vivo, in the absence of DNA. We propose that this may be the ‘storage form’ of RecG and PriA. We further propose that when forks stall, RecG and PriA are targeted to the fork by SSB, which, by virtue of its high affinity for single‐stranded DNA, allows these helicases to outcompete other proteins. This ensures their actions in the early stages of the rescue of stalled replication forks. 相似文献
53.
DL?MagerEmail author AD?Haffajee PM?Devlin CM?Norris MR?Posner JM?Goodson 《Journal of translational medicine》2005,3(1):27
Background
The purpose of the present investigation was to determine if the salivary counts of 40 common oral bacteria in subjects with an oral squamous cell carcinoma (OSCC) lesion would differ from those found in cancer-free (OSCC-free) controls. 相似文献54.
LN Barlow-Mosha DS Bagenda PK Mudiope MC Mubiru LM Butler MG Fowler PM Musoke 《African health sciences》2012,12(3):249-258
Background
Access to pediatric antiretroviral formulations is increasing in resource-limited countries, however adult FDCs are still commonly used by antiretroviral therapy (ART) programs.Objective
To describe long-term effectiveness of using adult FDC of d4T+3TC+NVP (Triomune) in children for HIV treatment.Methods
Clinical, immunologic, and virologic outcomes of HIV-infected ART-naïve children aged six months to 12 years, were evaluated up to 96 weeks post-ART initiation.Results
From March 2004 to June 2006, 104 children were followed with a median age of 5.4 years, median CD4 cell percent and HIV-1 RNA were 11.0% (IQR 6.7–13.9) and 348,846copies/mL (IQR 160,941–681,313) respectively at baseline. Using Kaplan-Meir estimates, 75% of children had undetectable viral loads (<400copies/mL) at 96weeks of ART. Children with a baseline CD4 cell percent >15% were 3 times more likely to achieve viral load <400copies/mL than those with baseline CD4 cell percent <5% after adjusting for baseline age {aHR = 3.03 (1.10–8.32), p=0.03}; no difference was found among those with CD4 cell percent >5–14.9% and <5%.Conclusion
Treatment with generic adult FDC for HIV-infected Ugandan children led to sustained clinical, immunologic and virologic response during 96 weeks of ART. Early initiation of ART is key to achieving virological success. 相似文献55.
56.
PN McDOUGALL PM LOUGHNAN NT CAMPBELL M HOCHMANN BJ TIMMS WW BUTT 《Journal of paediatrics and child health》1995,31(4):292-296
Objective: To report ventilation strategies, survival and complications in 39 outborn infants treated with high frequency oscillatory ventilation (HFOV).
Methodology Data were collected prospectively between 1 May 1992 and 31 December 1993 on all infants treated with HFOV who had severe respiratory failure despite optimal conventional ventilation.
Results Twenty-eight out of 39 (72%) survived. Of the 15 infants with birthweights <1500g, eight survived. Best survival rates were for infants with pulmonary interstitial emphysema with air leak (4/5) and for infants of birthweight >1500g with hyaline membrane disease (8/8), and meconium aspiration syndrome (7/7). Three infants deteriorated while on HFOV and required extracorporeal membrane oxygenation. Complications were: (i) development of pulmonary interstitial emphysema (1); (ii) recurrence of pneumothorax (3); (iii) hypotension (2); and (iv) bronchopulmonary dysplasia (9). One of the eight infants weighing <1500g who received HFOV in the first week of life developed periventricular haemorrhage.
Conclusion The initial results of HFOV for severe respiratory failure were encouraging although a learning curve was encountered with its introduction. 相似文献
Methodology Data were collected prospectively between 1 May 1992 and 31 December 1993 on all infants treated with HFOV who had severe respiratory failure despite optimal conventional ventilation.
Results Twenty-eight out of 39 (72%) survived. Of the 15 infants with birthweights <1500g, eight survived. Best survival rates were for infants with pulmonary interstitial emphysema with air leak (4/5) and for infants of birthweight >1500g with hyaline membrane disease (8/8), and meconium aspiration syndrome (7/7). Three infants deteriorated while on HFOV and required extracorporeal membrane oxygenation. Complications were: (i) development of pulmonary interstitial emphysema (1); (ii) recurrence of pneumothorax (3); (iii) hypotension (2); and (iv) bronchopulmonary dysplasia (9). One of the eight infants weighing <1500g who received HFOV in the first week of life developed periventricular haemorrhage.
Conclusion The initial results of HFOV for severe respiratory failure were encouraging although a learning curve was encountered with its introduction. 相似文献
57.
Monica Matus-Ridley R. Beverly Raney Hasina Thawerani Anna T. Meadows 《Pediatric blood & cancer》1983,11(2):99-105
The pathologic materials and clinical courses of 36 children aged 1 month-22 years, with histiocytosis × (H-X) seen at the Philadelphia Children's Cancer Research Center from 1970 to 1979 were reviewed. The pathologic subtype of H-X was favorable (type II) in 31 patients, unfavorable (type I) in one patient, and unclassified in four patients whose specimens were limited to a skin biopsy. Sixteen patients had localized H-X involving bone (14 patients), soft tissue (1 patient), or skin only (1 patient); all are alive and well after treatment with surgery alone (12 patients), radiation therapy (RT) (3 patients), or observation (1 patient); only 1 of the 16 developed recurrent H-X. The other 20 patients presented with multifocal H-X involving the skeleton alone (3 patients); the skeleton and soft tissues other than liver (7 patients); soft tissue exclusive of the liver (3 patients); soft tissue including the liver (4 patients); or soft tissues, skeleton, and liver or multiple drugs ± RT (15 patients). Seven of the 20 patients are alive and well without recurrence at a median of 4 years after diagnosis. Nine of the 20 patients, including 3 with liver dysfunction, responded completely to initial therapy but developed recurrence; each was retreated with drugs and is alive and well at a median of 4 years. The remaining 4 patients had widespread disease with dysfunction of the liver and/or hematopoietic system at diagnosis, failed to respond, and died. We conclude that (1) patients with multiple bony lesions with or without associated soft tissue disease or skin involvement have a favorable outlook and do not require systemic chemotherapy; (2) systemic treatment also is unnecessary for patients with localized H-X since recurrence is rare; (3) drugs can benefit patients with multifocal H-X, although the optimal duration of therapy is unclear; and (4) favorable response to treatment indicates high probability of disease-free survival. However, organ dysfunction at diagnosis is ominous: four of seven patients with liver dysfunction are dead, as are all three patients who prsented with peripheral blood count depression. 相似文献
58.
Richard Beverly Raney Jane Meza James R. Anderson Christopher J. Fryer Sarah S. Donaldson John C. Breneman Thomas J. Fitzgerald Edmund A. Gehan Jeff M. Michalski Jorge A. Ortega Stephen J. Qualman Eric Sandler Moody D. Wharam Eugene S. Wiener Harold M. Maurer William M. Crist 《Pediatric blood & cancer》2002,38(1):22-32
59.
Kroese ED; Dortant PM; van Steeg H; van Oostrom CT; van der Houven van Oordt CW; van Kranen HJ; de Vries A; Wester PW; van Kreijl CF 《Carcinogenesis》1997,18(5):975-980
E mu-pim-1 transgenic mice are predisposed to develop lymphomas. Due to
their low spontaneous tumour incidence and their increased sensitivity
towards the lymphomagen ethylnitrosourea these mice may present an
interesting model for short-term carcinogenicity testing. Here, we report
on the further exploration of this transgenic mouse model with two
additional carcinogens known to have, among others, the
lymphohaematopoietic system as target, i.e. benzo[a]pyrene (B[a]P) and
12-O-tetradecanoylphorbol-13-acetate (TPA). B[a]P, given three times a week
(by gavage) for 13 weeks at 4.3, 13 or 39 mg/kg body weight, resulted in a
dose-related increase in lymphomas up to a 90% incidence in E(mu)-pim-1
mice during the observation period of 40 weeks. B[a]P also induced tumours
of the forestomach within this observation period, though at a lower
incidence and apparently equally effective in wildtype and transgenic mice.
TPA, on the other hand, was unable to induce lymphomas (or tumours in any
other organ) in either transgenic or wildtype animals within the
observation period of 44 weeks, when applied dermally at the maximum
tolerated dose of 3 microg/mouse, twice a week for 35 weeks. Molecular
analysis showed that B[a]P-induced lymphomas in transgenic mice were of
T-cell origin, 80% of which had elevated levels of c-myc expression. None
of the lymphomas had increased N-myc expression and mutation analysis of
the ras-gene family revealed a K-ras mutation in only one out of eight
tumours investigated. Also, none of the lymphomas showed aberrant
expression of p53 as determined by immunohistochemistry. It is concluded
that the E mu-pim-1 mouse model will not be very suitable for short-term
carcinogenicity testing in general: only genotoxic chemicals that have the
lymphohaematopoietic system as target for carcinogenesis in wild- type
mice, appear to be efficiently identified.
相似文献
60.
Expression of differential nitric oxide synthase isoforms in human normal gastric mucosa and gastric cancer tissue 总被引:10,自引:2,他引:10
The present study investigated the expression and distribution of three
isoforms of nitric oxide synthase (NOS) in different anatomical regions of
the human stomach and in gastric neoplastic tissues by immunohistochemistry
using specific antibodies. Intracellular localization of individual
isoenzymes of NOS was detected in normal gastric mucosa. Gastric cancer
tissues had a marked reduction of all three NOS isoforms expression. The
expression of the endothelial NOS, neuronal NOS and inducible NOS in the
tumor tissue was significantly lower than in normal gastric mucosa (P =
0.01, P = 0.02, P < 0.01, respectively). In the tumor tissue the
expression of inducible NOS was significantly lower than the expression of
both constitutive forms of NOS (P < 0.01). There was a tendency to
higher expression of both constitutive forms of NOS in earlier stages T2 of
the tumor compared to advanced T4 tumor. In contrast, the expression of
inducible NOS was higher than in the advanced T4 tumor than in the earlier
stages T2 of the tumor. The mapping of the expression of endothelial NOS,
neuronal NOS and inducible NOS in human stomach showed higher expression of
NOS isoforms in the distal third than in the proximal third of the stomach
(P = 0.03, P = 0.04, P = 0.01, respectively). We conclude that there is
greater expression of NOS in the stomach corpus and in antrum than in the
proximal third of the normal human stomach mirroring the anatomical
predilection of common pathological changes in this part of the human
stomach. Furthermore, there was loss of the expression of individual
isoenzymes in gastric neoplasms.
相似文献