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81.
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83.
Macdonald RL Zhang ZD Curry D Elas M Aihara Y Halpern H Jahromi BS Johns L 《Neurosurgery》2002,51(3):761-8; discussion 768-70
OBJECTIVE: Hemoglobin contributes to vasospasm after subarachnoid hemorrhage. One mechanism may involve binding of nitric oxide, destruction of nitric oxide, or both. Support for this mechanism would be evidence that nitric oxide donors prevent vasospasm. This study attempted to provide such evidence. METHODS: A randomized, blinded study was conducted in which 13 monkeys underwent cerebral angiography and creation of a right subarachnoid hemorrhage. Subcutaneous osmotic pumps were implanted to deliver sodium nitroprusside (n = 7) or vehicle (n = 6) via catheters into the right basal cisterns. Seven days later, angiography was repeated, and the animals were humanely killed. Levels of cyclic nucleotides, hemoglobins, and thiocyanate were measured. RESULTS: Significant vasospasm of the right middle cerebral artery was present in animals treated with sodium nitroprusside (35 +/- 22% reduction in diameter, P < 0.05, paired t test) and placebo (28 +/- 20% reduction, P < 0.05, not significantly different from nitroprusside group by unpaired t test). Adequate delivery of sodium nitroprusside was supported by the finding of a significant increase in cyclic guanosine monophosphate levels in the cerebral arteries of treated animals compared with placebo (P < 0.05, unpaired t test). Thiocyanate was not present in significantly increased amounts in animals treated with nitroprusside, although this group did display elevated concentrations of nitrosyl hemoglobin (measured by electron paramagnetic resonance spectroscopy) and cyanomethemoglobin (measured by spectrophotometry) in the cerebrospinal fluid on Day 7. CONCLUSION: The lack of effect of sodium nitroprusside was not the result of inadequate drug delivery because cyclic guanosine monophosphate levels were significantly increased in vasospastic arteries. Vasospasm may not have been prevented because of a toxic effect of sodium nitroprusside metabolites, involvement of smooth muscle relaxation or contraction processes downstream of cyclic guanosine monophosphate, or both. 相似文献
84.
Wang JF; Bashir M; Engelsberg BN; Witmer C; Rozmiarek H; Billings PC 《Carcinogenesis》1997,18(2):371-375
Chromium (Cr) is a human carcinogen and a potent DNA damaging agent.
Incubation of DNA with CrCl3 resulted in dose-dependent binding of Cr to
DNA and, at concentrations >20 microM, altered the electrophoretic
mobility of a 100 bp oligonucleotide. We also demonstrate that high
mobility group (HMG) proteins 1 and 2 bind Cr-damaged DNA (Cr-DNA). Protein
binding was lesion density-dependent, with maximal binding to DNA treated
with 100 microM CrCl3. HMG2 binds to Cr-DNA with a calculated Kd of
approximately 10(-9) M. These proteins also bound DNA obtained from
chromate-treated cells. These results suggest that the covalent attachment
of Cr to DNA induces alterations in DNA structure which are recognized by
HMG1 and HMG2. Therefore, these proteins may function as Cr-damaged DNA
recognition proteins in vivo and as a consequence of binding, may play a
role in directing the cellular response to Cr-DNA adduct formation.
相似文献
85.
Bahia Namavar Jahromi Jaleh Zolghadri Elham Rahmani Shohreh Alipour Zahra Anvar Afsun Zarei Pegah Keramati 《Taiwanese journal of obstetrics & gynecology》2019,58(2):255-260
Objective
Ovarian hyperstimulation syndrome (OHSS) is a major complication of assisted reproductive technologies (ART). Polycystic ovary syndrome (PCOS) is a risk factor for OHSS. The aim of this randomized clinical trial (RCT) was to study the effect of low-dose aspirin (LDA) on the development of OHSS and ART outcomes in PCOS during ART.Materials and methods
This double-blinded placebo controlled RCT was performed on 232 PCOS infertile women in their first ART cycles during 2010–2016. LDA and placebo capsules were prepared, packed and specified by code numbers in similar shapes. One package was given to every woman and asked to take one capsule/day since the 21st day of her cycle prior to the gonadotropin stimulation. Gonadotropin releasing hormone agonist long protocol and triggering by human chorionic gonadotropin were used. Development of moderate to severe OHSS and their ART outcomes were documented then the codes were broken and data analyzed. Chi-square and Mann–Whitney U tests were used for the statistical analyses.Results
Eighteen cases that did not follow the study design were excluded. 214 cycles remained for the final analyses with 109 cases in LDA and 105 in the placebo group. Rate of the moderate to severe OHSS in LDA group was 34.9% compared to 30.5% in placebo group (P = 0.494). Fertilization rate was 71.8% vs 65.1% (P = <0.001) and the mean number of grade III embryos were 3.28 ± 3.53 vs 1.46 ± 1.42 (P = 0.014) in LDA and placebo groups, respectively. The mean number of the oocytes in different grades, total and frozen embryos also implantation and clinical pregnancy rates were not different between the groups.Conclusion
Moderate to Severe OHSS was not decreased but fertilization rate and the mean number of poor quality embryos were increased in LDA arm.Registration number
IRCT 201105216541N1. 相似文献86.
Arthrofibrosis following total knee replacement (TKR) is a relatively common complication which results in a reduction in knee range of movement and patient dissatisfaction. A retrospective study examined the relationship between anticoagulation with therapeutic warfarin and rates of arthrofibrosis following TKR. Arthrofibrosis was defined as less than 80 degrees of knee flexion 6-8 weeks post-TKR. Patients were warfarinised if they had a history of thrombophilic tendencies or medical conditions necessitating anti-coagulation, rather than as routine thromboprophylaxis. All other patients received thromboprophylaxis using low molecular weight heparin. A total of 728 patients underwent 874 primary TKR between 1993 and 2002 in one centre, performed by four surgeons. Mean age was 68 years (range 48-89 years) and there were 483 female and 391 male knees. Eighty cases were warfarinised post-operatively (53 female, 27 male). Overall, 83 of 874 TKRs (9%) had arthrofibrosis (57 female, 26 male) requiring manipulation under anaesthetic (MUA). In the warfarinised group, 21 knees (26%) had an MUA (15 female, 6 male). This compared to 62 cases (8%) requiring MUA in the non-warfarinised group (42 female, 20 male). There was a statistically significant difference on Fisher's exact testing (P<0.0001) between groups. Following MUA, knee flexion improved in 95% cases to a minimum 95 degrees but 8 cases had a fixed flexion deformity of 5-10 degrees . In conclusion, therapeutic warfarinisation post-TKR leads to a statistically greater chance of the patient developing arthrofibrosis compared to prophylactic low molecular weight heparin and that patients should be counseled appropriately. 相似文献
87.
Parsanezhad ME Alborzi S Namavar Jahromi B 《Archives of gynecology and obstetrics》2004,269(2):125-129
Objective: The purpose of this study was to examine the effects of of bromocriptin combined with clomiphene citrate in clomiphene-resistant
patients with polycystic ovary syndrome and normal prolactin level. Design: Prospective, double-blind, controlled study. Setting: University teaching hospital. Patients: One hundred polycystic ovary patients and normal prolactin (PRL) who were clomiphene citrate resistant. Interventions: Treatment group received 150 mg clomiphene citrate on days 5–9 and 7.5 mg bromocriptin continuously. Control group received
the same protocol of clomiphene citrate combined with placebo. Main outcome measures: Hormonal status, follicular monitoring, ovulation rate. Results: Follicular development (follicular size greater than 15 mm) was observed in 12 (25.5%) and eight (15.1%) women in treatment
and placebo group respectively (P=0.29). The serum prolactin level was within normal limits in all patients before treatment. After 3 and 6 months of treatment
with bromocriptin, there was a significant decrease in serum level of prolactin (P=0.000001).No any significant differences was seen in ovulation, and serum levels of follicle-stimulating hormone (FSH), luteinizing
hormone (LH), dehydroepiandrosterone sulfate (DHEAS), progesterone (P) between treatment and placebo group after treatment.
Conclusions: The only significant effect of long-term bromocriptin therapy in clomiphene citrate resistant polycystic ovary women was
to lower the serum prolactin concentration. It was also concluded that 10–15% of patients with polycystic ovaries experienced
occasional ovulatory cycles and pregnancy whether or not they were on treatment.
This work was performed at the Division of Infertility, Department of Obstetrics and Gynecology, School of Medicine, Shiraz
University of Medical Sciences, Shiraz, Iran. 相似文献
88.
INTRODUCTION: Allogeneic stem cell transplantation as a curative treatment for thalassemia major was established in Shiraz in 1993. In this article we describe our results of 10 years experience with allogeneic bone marrow transplantation for thalassemia major. METHODS: From June 1993 to January 2003, 112 cases of beta-thalassemia major underwent allogeneic marrow transplantation from HLA-identical or one antigen-mismatched related donors. Conditioning chemotherapy included busulfan (14 to 15 mg/kg), cyclophosphamide (200 mg/kg), and antithymocyte globulin (ATG; 40 mg/kg). Prophylaxis for graft-versus-host disease consisted of cyclosporine, prednisolone, and methotrexate. RESULTS: One hundred twelve patients with a diagnosis of beta-thalassemia major underwent allogeneic marrow transplantation during this period. The mean age of the patients was 9.5 years with the range of 2 to 20 years. The distribution of cases according to the Lucarelli classification were: 27 cases class I, 38 cases class II, and 47 cases class III. Eighty-seven of 112 patients (77.6%) with diagnosis of beta-thalassemia major are living with full engraftment at a median follow-up of 6 years (range 2 to 119 months). CONCLUSION: Allogeneic bone marrow transplantation has changed the outcome of disease dramatically. According to our results stem cell transplantation is the treatment of choice for class I and II (Lucarelli risk groups). Also, we recommend transplantation as a curative method for treatment of class III beta-thalassemic patients. 相似文献
89.
Treatment of allergic bronchopulmonary aspergillosis (ABPA) has remained both problematic as well as controversial. Although the sheet anchor in treatment of ABPA still remains steroids, various workers have tried oral antifungals (fluconazole and itraconazole) with encouraging results. This study evaluates the effect of fluconazole or itraconazole in the treatment of ABPA patients and compares them with the patients who had received palliative therapy other than antifungals. Case records of 44 proven cases of ABPA treated at our referral service hospital during February 1998 to April 2001 were analyzed. In addition to oral and inhaled bronchodilators, 16 patients received fluconazole 150 mg OD and 13 patients itraconazole 200 mg OD for six months. Response to therapy was assessed clinically, radiologically and by spirometry every 3 months. Patients who did not receive antifungals had chronic course characterized by airway obstruction, recurrent pulmonary consolidation and obstructive defect on pulmonary function test (PFT). Patients treated with itraconazole had better control of asthma symptoms, less requirement of reliever inhalers, steroids and lesser exacerbations of asthma during follow-up even after stopping antifungal. Fluconazole group had better control of symptoms but improvement in other parameters was not statistically significant. From this study it was evident that itraconazole improved the symptoms of airway obstruction, pulmonary functions, pulmonary opacities and decreased exacerbations during follow up.Key Words: Allergic bronchopulmonary aspergillosis, Fluconazole, Itraconazole 相似文献
90.
Parsanezhad ME Alborzi S Jahromi BN 《International journal of fertility and women's medicine》2002,47(6):272-277
OBJECTIVE: To evaluate the effects of administration of bromocriptine combined with clomiphene citrate (CC) in CC-resistant patients with polycystic ovary syndrome (PCOS) and normal prolactin (PRL) level. DESIGN: Prospective double-blind, placebo-controlled, randomized. SETTING: Referral university hospitals. PATIENTS: One hundred women with PCOS and normal PRL who failed to ovulate with a routine protocol of CC. INTERVENTIONS: Treatment group received 150 mg of CC from day 5 to 9 and 7.5 mg bromocriptine continuously, with hCG 10,000 units on day 16 or 17. Control group received the same protocol of CC combined with placebo. MAIN OUTCOME MEASURES: Follicular development, hormonal changes, ovulation rate, pregnancy rate. RESULTS: Follicular development (follicular size greater than 15 mm) was observed in 12 (25.5%) and 8 (15.1%) women in the treatment and placebo group, respectively (p = 0.29). The serum prolactin level was within normal limits in all patients before treatment. After 3 and 6 months of treatment with bromocriptine, there was a significant decrease in serum level of prolactin (p = 0.000001). No significant differences were seen in ovulation, pregnancy rate, or serum levels of FSH, LH, DHEAS, and progesterone between treatment and placebo groups after treatment. CONCLUSIONS: The only significant effect of long-term bromocriptine therapy in CC-resistant women with PCOS was to lower the serum PRL concentration. It is also concluded that 10%-15% of patients with PCOS experienced occasional ovulatory cycles and pregnancy whether or not they were on treatment. 相似文献