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2.
Lily Shum A B M Rabie Urban H?gg 《American journal of orthodontics and dentofacial orthopedics》2004,125(2):185-190
This study assessed the amount of vascular endothelial growth factor (VEGF) expression and related the findings to new bone formation in the posterior glenoid fossa during stepwise mandibular advancement. A total of 250 female Sprague-Dawley rats, 35 days old, were randomly divided into 10 groups, each including 5 control and 20 experimental rats. Within each group, 10 experimental rats were fitted with functional appliances with a 1-step advancement of 3.5 mm. Another 10 were fitted with stepwise appliances with an initial advancement of 2 mm and a subsequent increase to 3.5 mm on day 30. The rats in the experimental groups were killed on days 3, 7, 14, 21, 30, 33, 37, 44, 51, and 60, respectively. The matched controls were killed on the same time points. Sections (7 microm) were cut through the glenoid fossa sagittally and stained with anti-VEGF antibody. VEGF expression in the posterior glenoid fossa was evaluated with a computer-assisted image-analyzing system. Both VEGF expression and new bone formation were greater in the experimental rats than in the controls. During stepwise advancement, initial VEGF expression was less than that of 1-step advancement, but the second advancement elicited another peak on day 44. New bone formation was also less than that of 1-step advancement during early stages of stepwise advancement but then began to increase from day 37 onward. The maximum increase was observed on day 60. Stepwise advancement of the mandible delivers mechanical stimuli that produce a series of tissue responses that lead to increased vascularization and bone formation. 相似文献
3.
Metastatic tumours of the testes are uncommon, making up little more than 2% of all testicular neoplasms. The most frequent primary sites are the lung and prostate. Only rarely do these lesions present clinically either as the first sign of malignant disease or as a complicating factor during the course of known disease. The authors present two cases illustrating both of these occurrences. The first, a man with carcinoma of the common bile duct, initially had a mass in the testicle and the second, a patient with carcinoma of the prostate, had his clinical course complicated by a symptomatic metastasis to the right testis. The authors also reviewed their local autopsy experience and identified 16 more cases. Metastases were grossly visible in 38% (6 of 16). The most frequent primary sites were lung (four cases), stomach (four) and prostate (three). Routes of spread as well as possible explanations for the low incidence are discussed. 相似文献
4.
A method has been derived for calculating the mean absorption time of an oral drug and its interconversion metabolite which is generated from the drug systemically and presystemically. The method evolves from the convolution integral and requires plasma AUC and AUMC values after separate intravenous administration of the drug and its interconversion metabolite and oral administration of the drug. It can also be used to calculate the mean input time of a drug undergoing reversible metabolism and administered by any other extravascular route. Results of a simulation study using both errorless and errant data indicate that, when the absorption rate constant of a drug or its interconversion metabolite is not much larger than the apparent elimination rate constant, the proposed method performs satisfactorily. However, when the absorption rate constant of a drug or its interconversion metabolite is much larger than the apparent elimination rate constant, the proposed method appears to be inaccurate. 相似文献
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6.
Krushkal J; Xiong M; Ferrell R; Sing CF; Turner ST; Boerwinkle E 《Human molecular genetics》1998,7(9):1379-1383
Elevated blood pressure is an important risk factor for renal-, cerebro-
and cardiovascular diseases. We used an efficient discordant sib-pair
ascertainment scheme to investigate the impact of the distal end of the
long arm of human chromosome 5 (chromosomal region 5q31.1-qter) containing
genes for the alpha1B and beta2 adrenergic receptors and the dopamine
receptor type 1A on variation of systolic blood pressure in young
Caucasians. We measured eight highly polymorphic markers spanning this
positional candidate gene-rich region in 427 individuals from 55
three-generation pedigrees containing 69 discordant sibling pairs, and
calculated multipoint identity by descent (MIBD) probabilities. The results
of genetic linkage and association tests indicate that the region between
markers D5S2093 and D5S462 is significantly linked to one or more
polymorphic genes influencing interindividual variation in systolic blood
pressure levels. Since the alpha1B adrenergic receptor and dopamine
receptor type 1A genes are located close to these markers, these data
suggest that genetic variation in one or both of these G protein-coupled
receptors, which participate in the control of vascular tone, plays an
important role in influencing interindividual variation in systolic blood
pressure levels.
相似文献
7.
Kenneth Siu-Sing Leung Timothy Ting-Leung Ng Alan Ka-Lun Wu Miranda Chong-Yee Yau Hiu-Yin Lao Ming-Pan Choi Kingsley King-Gee Tam Lam-Kwong Lee Barry Kin-Chung Wong Alex Yat Man Ho Kam-Tong Yip Kwok-Cheung Lung Raymond Wai-To Liu Eugene Yuk-Keung Tso Wai-Shing Leung Man-Chun Chan Yuk-Yung Ng Kit-Man Sin Kitty Sau-Chun Fung Sandy Ka-Yee Chau Wing-Kin To Tak-Lun Que David Ho-Keung Shum Shea Ping Yip Wing Cheong Yam Gilman Kit-Hang Siu 《Emerging infectious diseases》2021,27(1):196
Initial cases of coronavirus disease in Hong Kong were imported from mainland China. A dramatic increase in case numbers was seen in February 2020. Most case-patients had no recent travel history, suggesting the presence of transmission chains in the local community. We collected demographic, clinical, and epidemiologic data from 50 patients, who accounted for 53.8% of total reported case-patients as of February 28, 2020. We performed whole-genome sequencing to determine phylogenetic relationship and transmission dynamics of severe acute respiratory syndrome coronavirus 2 infections. By using phylogenetic analysis, we attributed the community outbreak to 2 lineages; 1 harbored a common mutation, Orf3a-G251V, and accounted for 88.0% of the cases in our study. The estimated time to the most recent common ancestor of local coronavirus disease outbreak was December 24, 2019, with an evolutionary rate of 3.04 × 10−3 substitutions/site/year. The reproduction number was 1.84, indicating ongoing community spread. 相似文献
8.
Acute porphyria is rare in orientals. We describe a Chinese woman with recurrent generalised tonic-clonic seizures and abdominal pain. Genomic DNA studies identified a heterozygous base substitution from guanine to adenine at nucleotide position 503, resulting in substitution of arginine by histidine at position 168 of the protein (R168H). This genetic abnormality is similar to the mutation reported in Caucasians with variegate porphyria. To the best of our knowledge, this is the first report in the English literature a Chinese patient with variegate porphyria with an identifiable mutation. A brief review of porphyria is presented. 相似文献
9.
PEG-Hemoglobin as a resuscitation solution in the treatment of hypovolemic shock in the anesthetized rat 总被引:2,自引:0,他引:2
This study was designed to determine the advantages of using the hemoglobin-based oxygen carrier, polyethylene glycol conjugated bovine hemoglobin (PEG-Hb), as an additive to Ringer's lactate solution (RLS) for the treatment of acute hemorrhage in anesthetized female rats. Different compositions of PEG-Hb and RLS were administered intravenously in a paradigm that provided 30 ml/kg of resuscitation fluid following an episode of 15 min of hypotension. Hypotension was achieved by the removal of blood (1 ml/min) from the femoral vein until the mean arterial pressure was lowered to or below 50 mmHg and subsequently maintained until resuscitation. Short-term cardiovascular assessment showed that resuscitation fluids containing PEG-Hb resulted in higher mean arterial pressure, aortic blood flow, renal blood flow, and less dramatic shifts in arterial base excess and respiratory blood gases than plain RLS. The long-term survival experiment showed lower lactate dehydrogenase, alkaline phosphatase, and serum glutamic pyruvic transaminase levels in most groups resuscitated with solutions containing PEG-Hb, but no differences in survival (100%) were observed. The data suggest that the addition of PEG-Hb to RLS improves its resuscitative effects. Specifically, a solution of 50% RLS:50% PEG-Hb appeared to have the most favorable cardiovascular and metabolic effects in this anesthetized rat hypovolemic shock resuscitation model. Presumably, the improved effects seen with the addition of PEG-Hb were due to its innate plasma expansion and oxygen-delivery capabilities. 相似文献
10.
H J Pieniaszek A F Davidson J E Chaney L Shum C A Robinson M Mayersohn 《Xenobiotica; the fate of foreign compounds in biological systems》1999,29(9):945-955
1. The metabolism of moricizine.HCl was studied in 12 male volunteers dosed with 250 mg (300 microCi) 14C-radiolabelled drug. 2. Moricizine was biotransformed to many metabolites in humans (at least 35 plasma and 51 urine metabolites). 3. Urine and faecal combined mean (range) recovery accounted for 90.2% (73.4-101.6%) of the administered radioactivity, with most of the recovered radioactivity present in faeces (mean 58.4%; range 45.6-64.7%). Mean (range) urinary recovery was 31.8% (26.2-36.9%), with <1% of the dose recovered as intact moricizine, and no one metabolite accounting for >2.5% of the dose. 4. Total radioactivity (TR) plasma t1/2 was 85.2 h, while that for moricizine was 2.4 h. Mean half-lives for plasma metabolites ranged from 2.9 to 23.6 h. The largest portion (11%) of TR AUC (area under the plasma concentration-time curve) was attributed to 2amino-10-glucuronophenothiazine. Each of the other metabolites accounted for less of the TR AUC than parent drug except for two unidentified peaks which had comparable areas (approximately 5% of the total radioactivity area). 5. Two identified moricizine metabolites, 2-amino-10-(3-morpholinopropionyl) phenothiazine and ethyl [10-(3-aminopropionyl) phenothiazin-2-yl] carbamate, possess the structural characteristics proposed for class 1 anti-arrhythmic activity (pendant amine functionality) and have plasma half-lives 4-7-fold longer than moricizine. 相似文献