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An examination was made of neurogenesis in the anteroventral periventricular nucleus (AVPv) of the preoptic area of the rat using bromodeoxyuridine (BrdU), a thymidine analog, and a BrdU-specific antibody. Cells in the AVPv of adult rats were labeled with the antibody when BrdU was injected into pregnant rats once during day 13 to 18 of gestation, but not during day 10 to 12 nor 19 to 20 of gestation nor on postnatal day 1, indicating that neurogenesis of the AVPv occurs during a limited period from day 13 to 18 of gestation. Next, to examine the effects of androgen on neurogenesis, BrdU was injected once on day 15 into pregnant rats that also received injections of testosterone propionate (TP). The number of BrdU-labeled cells in the AVPv was similar in control female and male fetuses and female fetuses from pregnant rats that received daily injections of TP during days 14 to 16, when fetuses were examined on day 17 of gestation. These results suggest that the neurogenesis that was recognized by labeling with BrdU was not affected by the treatment with TP. On day 21 of gestation, BrdU-labeled cells in the AVPv of control male fetuses and female fetuses that received TP during days 14 to 18 were fewer in number than those in female fetuses of the control group, whereas treatments with TP during days 14 to 16 and during days 17 to 18 did not cause any significant decrease in number of BrdU-labeled cells. These findings support the hypothesis that elimination of a population of cells, for example, by cell death as described previously, is enhanced in male fetuses and in female fetuses treated with TP repetitively.  相似文献   
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OBJECTIVE: The study goal was to evaluate whether quantitative analysis of neck drainage contents is an important parameter of objective and early diagnosis of chylous fistula (CF) in the postoperative period. STUDY DESIGN AND SETTING: We prospectively evaluated 103 consecutive neck dissections during a 2-year period at a tertiary academic referral center. Six of the patients (5.8%) had CF. The data obtained from the patients with CF were matched with normal data obtained from patients without CF. RESULTS: A statistically significant difference was found between total drainage volumes of the patients with and those without CF (P < 0.05). In almost all patients with CF, drainage levels of triglycerides and cholesterol on postoperative day 1 were higher than serum levels. The difference between the drainage levels of triglycerides and cholesterol of the patients with and without CF was highly significant (P < 0.001). CONCLUSIONS: Serum and drainage levels of triglycerides and cholesterol on postoperative day 1 can be used as objective and early predictive parameters of CF.  相似文献   
4.
Discontinuation of medication is the treatment of choice for patients with chronic daily headache (CDH) who overuse their medications. This treatment may be difficult due to increased headache severity observed in patients immediately after withdrawal. We retrospectively evaluated the efficacy of valproic acid therapy in 66 patients with overuse of CDH medication during withdrawal therapy. Patients were all withdrawn from medications and valproic acid started at 250 mg or 500 mg daily. Forty-two (63.6%) patients had decreased headache severity, including 27.3% objective responses in the first week. At the last visit in the 12th week, 50 patients were headache-free and only one patient had persistent headache. Fifteen patients withdrew from therapy due to side effects and lost to follow-up within this timeframe. Thus, low dose valproic acid appears to be safe and effective in the management of withdrawal therapy.  相似文献   
5.
OBJECTIVE: The aim of this study was to assess the efficacy of inhaled morphine for preemptive analgesia in patients who undergo septoplasty or septorhinoplasty. STUDY PLAN AND METHODS: Eighty ASA I-II patients scheduled for septoplasty or septorhinoplasty were recruited and randomly divided into 2 groups that received different treatments 10 minutes prior to induction. The preemptive analgesia group (Group P, n = 40) received 65 mug kg(-1) morphine sulphate (a 3-mL volume) via an oral nebulizer, and the control group (Group C, n = 40) received 3 mL 0.9% sodium chloride (physiological saline) via the same type of nebulizer. Blood pressure, oxygen saturation, heart rate, time to first requirement for analgesia, and occurrence of nausea/vomiting were recorded. RESULTS: There were no significant differences between Groups P and C with respect to age, body weight, sex distribution, or duration of surgery. There was also no significant difference between the group frequencies of postoperative nausea/vomiting. The time to first requirement for analgesia was significantly longer in Group P than Group C. CONCLUSION: The results of this preliminary study suggest that a single dose of inhaled morphine administered preemptively prior to septoplasty or septorhinoplasty provides effective postoperative analgesia. EBM rating: B-3b.  相似文献   
6.
We investigated the effects of activated protein C resistance (APCR), Factor V Leiden (FVL) mutation, and high lipoprotein (a) levels in 32 young patients with branch retinal vein occlusion (BRVO) vs 30 controls. No difference between patients with BRVO and controls was found with regard to APCR, FVL mutation, or lipoprotein (a) levels. These factors do not seem important in the etiology of BRVO. The authors have stated that they do not have a significant financial interest or other relationship with any product manufacturer or provider of services discussed in this article. The authors also do not discuss the use of off-label products, which includes unlabeled, unapproved, or investigative products or devices.  相似文献   
7.
Eight patients with a delayed-onset heparin-induced thrombocytopenia, with thrombotic complications requiring immediate anticoagulation in 7 of them, were given low molecular weight heparin (LMWH) fractions as alternative therapy. This treatment led to normalization of platelet count within 3-5 days in 6 patients with clinical recovery in 5. In 2 patients, thrombocytopenia persisted despite LMWH therapy. In vitro platelet aggregation tests performed in all patients gave evidence of a relationship between the presence (or absence) of a LMWH-dependent platelet-aggregating factor in the patients' plasma and the persistence (or correction) of the thrombocytopenia with LMWH therapy. Although positive in vitro tests may not necessarily be associated with thrombocytopenia, in vitro testing may prove to be a useful guide before giving LMWH fractions as an alternative therapy in patients with heparin-induced thrombocytopenia requiring immediate anticoagulation.  相似文献   
8.
BACKGROUND AND OBJECTIVE: The complications of 25-gauge transconjunctival sutureless vitrectomy based on the surgical indications were reviewed. PATIENTS AND METHODS: Thirty-eight patients underwent 25-gauge transconjunctival sutureless vitrectomy. Indications for vitrectomy, preoperative and postoperative best-corrected visual acuity, preoperative and postoperative intraocular pressure, and any intraoperative or postoperative complications were recorded. RESULTS: Complications included the need to suture a leaking sclerotomy intraoperatively in four eyes (9%), all of which involved oil removal; postoperative hypotony with choroidals in two eyes (5%); mild progression of nuclear sclerotic cataract in one eye (2% of all eyes, 4% of phakic eyes); the need to switch to 20-gauge pars plana vitrectomy in one eye (2%); corneal abrasion in one eye (2%); and retinal detachment in one eye (2%). Sclerotomy leakage and hyopotony with choroidals were only encountered in cases involving previously vitrectomized eyes, whereas none of the eyes without previous vitrectomy had leakage-related complications. CONCLUSIONS: Previously vitrectomized eyes have a higher incidence of complications related to postoperative leakage, possibly due to the lack of plugging effect of peripheral vitreous on the unsutured sclerotomy. One should consider suturing any leaking sclerotomy at the conclusion of surgery involving previously vitrectomized eyes.  相似文献   
9.
The synthesis of high-molecular-weight polyethers and copolyethers based on 4-hydroxyacetophenone azine and α,ω-dibromoalkanes was carried out in N-methyl-2-pyrrolidone via Williamson etherification using the caesium salt of the diol. Polyethers were composed of a homologous series of flexible methylene spacers with m = 5?12, while the copolyethers contained a 1:1 mole ratio of two different spacers with m = 5/7, 6/8, 7/9, 8/10, 9/11 and 10/12. Polymers with relatively short spacers (m = 5?8 methylene groups) exhibit enantiotropic mesomorphism, whereas those having m = 8?11 are tentatively identified to be monotropic. The polyether with m = 12 is crystalline. Copolyethers are enantiotropic and their mesophase ranges are considerably wider than those of the homopolyethers. The mesophases were identified to be nematic by polarised light microscopy. The transition temperatures of both the homopolymers and copolymers show classical even-odd variations as a function of the spacer length.  相似文献   
10.
OBJECTIVE: Polycystic ovary syndrome (PCOS) is frequently associated with insulin resistance and a consequent increased risk of metabolic diseases. The aim of the present study was to investigate the role of adiponectin in insulin resistance in PCOS women. MATERIALS AND METHODS: Forty-seven patients with PCOS and 23 control subjects, matched for age and body mass index (BMI), were enrolled in the study. Clinical, metabolic and hormonal parameters and adiponectin levels were measured, and HOMA-IR score (homeostasis model assessment-insulin resistance index) was calculated for each subject. RESULTS: There was no difference in adiponectin levels between PCOS patients and the control group. However, adiponectin levels were negatively correlated with obesity-associated parameters and HOMA-IR score in PCOS patients and controls. As adiponectin is modulated by BMI we adjusted for BMI among the PCOS patients, and found a negative correlation between adiponectin levels and HOMA-IR score (r = -0.51, p < 0.001). Adiponectin and BMI were independent determinants of insulin resistance in PCOS patients (adjusted R2 = 0.66, p < 0.001). CONCLUSION: Adiponectin did not seem to be actively involved in the pathogenesis of PCOS. However, adiponectin levels were independently associated with insulin resistance in PCOS patients, suggesting that adiponectin might play a role in the complicated metabolic abnormalities of PCOS.  相似文献   
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