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Introduction : Hypertrophic scar is a devastating sequel to burns and other tangential skin injuries. It follows deep dermal injuries and does not occur after superficial injuries. Nitric oxide (NO) plays many important roles in wound healing from inflammation to scar remodeling. Studies have shown that expression of nitric oxide synthase and nitric oxide production are decreased in human hypertrophic scar. However little is known about NO involvement in the early stages of hypertrophic scarring, because of the lack of an animal model. It was recently reported that the female red Duroc pig (FRDP) makes thick scar, which is similar to human hypertrophic scar. We hypothesized that NO production in wounds on the female, red Duroc pig is similar to that of human hypertrophic scar and that NO involvement in deep wounds is different from that in superficial wounds. Methods : Superficial (0.015” to 0.030”) and deep (0.045” to 0.060”) wounds were created on the backs of four FRDPs. Biopsies were collected at weeks 1.5, 4, 8 and 21 post wounding including samples of uninjured skin. Nitric oxide levels were measured with the Griess reaction assay and normalized with tissue protein level. Results : Superficial wounds healed with an invisible scar whereas the deep wounds healed with scar resembling mild hypertrophic scar. The thickness of the scars from the deep wounds was significantly greater than uninjured skin and healed superficial wounds (p < 0.01). NO levels were increased at 1.5 weeks in deep wounds compared to superficial wounds and uninjured skin (p < 0.05). At 8 weeks, NO levels in deep wounds had returned to the level of uninjured tissue and superficial wounds. By 21 weeks, NO levels had decreased significantly when compared to superficial wounds (p < 0.01). There were no differences in NO levels between uninjured skin and superficial wounds at any time point (p > 0.05). Conclusions : NO production is similar in late, deep wounds on the female, red Duroc pig to that reported in the literature for human hypertrophic scar further validating this animal model. NO production is quite different after deep wounds as compared to superficial wounds in the FRDP. Early elevation in nitric oxide production might account for excessive inflammation in deep wounds that become thick scars in the FRDP. Nitric oxide regulators and effects at early stages of scar formation should be elucidated further and the FRDP appears to be a useful model. 相似文献
3.
乳腺管状小叶癌(Tubulolobular carcinoma,TLC)最初是被作为小叶癌的管状变型。作者总结了27例TLC的组织学、免疫表型和临床特征,并与纯小管癌和经典型小叶癌进行了比较。此组患者年龄43-79岁(中位年龄60岁)。1例双侧乳腺受累,5例病变为多灶性。肿瘤直径0.5-2.5cm,色灰褐,质硬。组织学观察:TLC的肿瘤细胞形成管状和条索状两种结构模式并相互混杂,且两者比例相当(统称为管状小叶模式)。 相似文献
4.
Hugues JN Soussis J Calderon I Balasch J Anderson RA Romeu A;Recombinant LH Study Group 《Human reproduction (Oxford, England)》2005,20(3):629-635
BACKGROUND: In anovulatory women undergoing ovulation induction, addition of recombinant human LH (rLH) to FSH treatment may promote the dominance of a leading follicle when administered in the late follicular phase. The objective of this study was to find the optimal dose of rLH that can maintain the growth of a dominant follicle, whilst causing atresia of secondary follicles. METHODS: Women with infertility due to anovulation and over-responding to FSH treatment were randomized to receive, in addition to 37.5 IU recombinant human FSH (rFSH), either placebo or different doses of rLH (6.8, 13.6, 30 or 60 microg) daily for a maximum of 7 days. The primary efficacy endpoint was the proportion of patients who had exactly one follicle > or = 16 mm on hCG day. RESULTS: Among 153 enrolled patients, the five treatment groups were similar in terms of baseline characteristics. The proportion of patients with exactly one follicle > or = 16 mm ranged from 13.3% in the placebo group to 32.1% in the 30 microg rLH group (P = 0.048). The pregnancy rate ranged from 10.3% in the 60 microg group to 28.6% in the 30 microg rLH group. Adverse events were similar between groups. CONCLUSIONS: In patients over-responding to FSH during ovulation induction, doses of up to 30 microg rLH/day appear to increase the proportion of patients developing a single dominant follicle (> or = 16 mm). Our data support the 'LH ceiling' concept whereby addition of rLH is able to control development of the follicular cohort. 相似文献
5.
Dopamine D2 receptor occupancy by olanzapine or risperidone in young patients with schizophrenia 总被引:1,自引:0,他引:1
Lavalaye J Linszen DH Booij J Reneman L Gersons BP van Royen EA 《Psychiatry research》1999,92(1):33-44
A crucial characteristic of antipsychotic medication is the occupancy of the dopamine (DA) D2 receptor. We assessed striatal DA D2 receptor occupancy by olanzapine and risperidone in 36 young patients [31 males, 5 females; mean age 21.1 years (16-28)] with first episode schizophrenia, using [123I]iodobenzamide (IBZM) SPECT. The occupancy of DA D2 receptors was not significantly different between olanzapine and risperidone. However, in subgroups of most prescribed doses, DA D2 occupancy was higher in the risperidone 4-mg group (79%) compared to the olanzapine 15-mg group (62%). [123I]IBZM binding ratios decreased with olanzapine dose (r = -0.551; P < 0.01), indicating higher DA D2 receptor occupancy with higher olanzapine dose. Akathisia and positive symptoms were correlated with [123I]IBZM binding ratio (r = -0.442; P < 0.01; and r = -0.360; P < 0.05, respectively). Prolactin (PRL) levels were elevated in the risperidone, but not in the olanzapine group, at comparable D2 receptor occupancy levels. In the olanzapine group, PRL levels were correlated with [123I]IBZM binding ratio (r = -0.551; P < 0.01). In conclusion, both olanzapine and risperidone induce a high striatal D2 receptor occupancy, dependent on dose and group formation. The lower incidence of prolactin elevation with olanzapine, compared to risperidone, may not be attributed to a lower D2 receptor occupancy. 相似文献
6.
Harley B Messinger Egilius LH Spierings Arnaud JP Vincent John Lebbink 《Cephalalgia : an international journal of headache》1991,11(1):13-18
In two headache questionnaire surveys we inquired about the occurrence of headache in the mothers, fathers, siblings and children of the respondents. In total, 633 people completed valid questionnaires, 260 in the first survey and 373 in the second. The hypothesis was that familial headache occurrence would be positively associated with headache frequency. In each survey, the regression of headache frequency on the number of parents having headache was highly significant. Neither sex nor the sibling and children variables were significant predictors. In the cross-tabulations of the parental occurrence of headache with headache frequency we saw a clear "break-point" between the "no headache" and the headache frequency categories studied. For the final analyses the dichotomy "headache/no headache" was related in fourfold tables to headache occurrence in the father and the mother separately, and to the number of headache parents. The positive associations were not simply due to the large number of migraine cases since they remained after removing the migraineurs. 相似文献
7.
Although pancuronium has fewest side effects compared to other currently used non-depolarizing muscle relaxants, it is still not the ideal relaxant. Its structural analogues have been studied to derive such an ideal relaxant. Org-Nc45 meets the requirements for such a relaxant best and is therefore extensively studied. It is more potent than pancuronium, has a shorter onset and duration of action and is free from cardiovascular side effects. Histamine release could not be demonstrated. It can be easily reversed by neostigmine, pyridostigmine or 4-aminopyridine. Interaction with antibiotics and anaesthetic drugs is not different from that of pancuronium. 相似文献
8.
L. Viinikka O. Ylikorkala R. Vihko H. P. Wijnand M. Booij F. van der Veen 《European journal of clinical pharmacology》1979,15(5):349-355
Summary The pharmacokinetics of a new synthetic progestagen, Org 2969 (13-ethyl-11-methylene-18,19-dinor-17-pregn-4-en-20-yn-17-ol) and its presumed active metabolite, 3-keto-Org 2969, were studied in five healthy female volunteers. During the first part of the study (Phase I), four volunteers ingested as a single dose 50 µg (about 100 µCi) of [16-3H]-Org 2969 together with 50 µg of ethinyl oestradiol. During the second part (Phase II), ten days of pretreatment with non-readioactive Org 2969 and ethinyl oestradiol preceded dosing, which was similar to that in Phase I. The fifth volunteer ingested 2500 µg of Org 2969 as a single dose. The concentrations of Org 2969 and 3-keto-Org 2969 in serum were measured by specific radioimmunoassay, and by as radioactivity. The maximum serum level of Org 2969 of 0.2–0.3% of the dose/litre was obtained 0.8–1.3 h after administration, and it was followed by a mono-exponential decrease, the half-life being 1.3–1.5 hours. No difference in Org 2969 levels was seen between Phase I and Phase II studies. The maximum 3-keto-Org 2969 serum level in Phase I was 0.4–0.8% of the dose/litre, 1–3 h after administration. A two-compartment open body model adequately described the data. The half-life of elimination was 16 hours. There was a considerable change in the single dose kinetics between Phase I and Phase II in the case of 3-keto-Org 2969. In Phase II the maximum serum level was 2.0–3.4% of the dose/litre, and there was no significant change in half-life. The change was considered to be due to a decrease in the apparent volume of distribution as a result of an increased number of binding sites on sex hormone-binding globulin induced by ethinyl oestradiol during the pretreatment period, and/or to an increase in the fraction of Org 2969 metabolized to 3-keto-Org 2969. The two simultaneous processes contributed to the change in kinetics and to the production of a steady state level of 3-keto-Org 2969 which resulted in a steady state within the first 10 days of daily administration of Org 2969 and ethinyl oestradiol.The following codes and trivial names were used Org 2969
13-ethyl-11-methylene-18, 19-dinor-17-pregn-4-en-20-yn-17-ol
- 3-keto-Org 2969
13-ethyl-17-hydroxy-11-methylene-18, 19-dinor-17-pregn-4-en-20-yn-3-one
- ethinyl oestradiol
17-ethinyl-1,3,5(10)-oestratriene-3,17-diol
- lynestrenol
19-nor-17-pregn-4-en-20-yn-17-ol
- norgestrel
13-ethyl-17-hydroxy-18,19-dinor-17-pregn-4-en-20-yn-3-one 相似文献
9.
Early stage nasopharyngeal carcinoma: radiotherapy dose and time factors in tumor control 总被引:1,自引:0,他引:1
Chang JT; See LC; Liao CT; Chen LH; Leung WM; Chen SW; Chen WC 《Japanese journal of clinical oncology》1998,28(3):207-213
OBJECTIVE: To evaluate radiotherapy dose and length of treatment in the
control of early stage nasopharyngeal carcinoma (NPC) treated with a
combination of external radiotherapy and brachytherapy, MATERIALS &
METHODS: We reviewed the records of 133 patients with early stage
nasopharyngeal carcinoma (stage I or II, AJC/UICC staging system) who
received definitive radiotherapy in Chang Gung Memorial Hospital from 1979
to 1991. The median follow-up time was 7.1 years with a minimum of 2 years.
All patients were treated with megavoltage external radiotherapy to the
nasopharynx area (63-72 Gy) followed by high dose rate intracavitary
brachytherapy (5-16.5 Gy in one to three fractions, spaced 1-2 weeks
apart). The median total dose and time of irradiation was 75 Gy (69.8-81.4
Gy) and 11.6 weeks (7.8-20 weeks) respectively. Survival analysis was used
to examine the effect of several variables on prognosis. RESULTS: The
5-year rates were 86.4% for local control, 84.7% for disease free survival,
88.5% for actuarial survival and 84.2% for overall survival. The treatment
group (combination of time and dose of irradiation) was the most important
prognostic factor according to Cox's proportional hazard model. Patients
receiving radiation at a total dose of < or = 75 Gy completed in < 12
weeks showed the best prognosis. CONCLUSION: Treatment time and total
treatment dose are both important factors in treating early stage NPC.
Decreasing the total radiation time to < 12 weeks and not exceeding a
radiation dose of 75 Gy gave the best results.
相似文献
10.
Jan-Peter van Wieringen Jan Booij Vladimir Shalgunov Philip Elsinga Martin C. Michel 《Naunyn-Schmiedeberg's archives of pharmacology》2013,386(2):135-154
Dopamine D2 receptors, similar to other G-protein-coupled receptors, exist in a high- and low-affinity state for agonists. Based upon a review of the methods for detecting D2 receptor agonist high-affinity states, we discuss alterations of such states in animal models of disease and the implications of such alterations for their labelling with positron emission tomography (PET) and single-photon emission computed tomography (SPECT) tracers. The classic approach of detecting agonist high-affinity states compares agonist competition for antagonist radioligands, in most cases using [3H]-spiperone as the radioligand; alternative approaches and radioligands have been proposed, but their claimed advantages have not been substantiated by other investigators. In view of the advantages and disadvantages of various techniques, we critically have reviewed reported findings on the detection of D2 receptor agonist high-affinity states in a variety of animal models. These data are compared to the less numerous findings from human in vivo studies based on PET and SPECT tracers; they are interpreted in light of the finding that D2 receptor agonist high-affinity states under control conditions may differ between rodent and human brain. The potential advantages of agonist ligands in studies of pathophysiology and as diagnostics are being discussed. 相似文献