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821.
Role of prostaglandin E in the biphasic fever response to endotoxin   总被引:5,自引:0,他引:5       下载免费PDF全文
Biphasic fevers were induced in sheep with intravascular infusions or injections of 4-10 μg (80-200 ng/kg) of endotoxin, whereas monophasic fevers were obtained with doses of 1-2/μg (20-40 ng/kg). A marked increase in arterial blood pressure invariably accompanied the onset of fever; the latency of responses to the higher and lower doses of endotoxins averaged 26 min and 42 min, respectively. Prostaglandin (PG) assays of plasma from the carotid artery and jugular vein during fever episodes revealed a surge of PGE and PGF coincident with the pressor response and the first phase of fever, but PG were not detected in plasma samples taken throughout the second phase of fever. PG measurements of arterial and venous plasma collected at a distal site (hind limb) showed a similar surge of PGE and PGF in association with the early fever response, indicating that intravascular PG synthesis and release represents a generalized systemic response to circulating endotoxin. Carotid arterial infusions of PGE(2) produced immediate monophasic fevers and pressor responses, whereas PGD(2) infusions produced an immediate pressor effect but no fever. Infusions of PGF(2α) or prostacyclin, however, evoked neither fever nor pressor effects. Intracarotid infusions of leukocyte pyrogen (LP) caused monophasic fevers with latent periods of 15-20 min but pressor responses were not seen and neither PGE nor PGF were detected in plasma samples from the carotid artery or jugular vein before or during fever. Indomethacin, a potent inhibitor of arachidonic acid metabolism, blocked fever responses to endotoxin and to LP. These findings implicate PGE as the mediator of the early phase of endotoxin fever and imply a role for another pyrogenic metabolite ofarachidonic acid in the mediation of the second phase of fever, i.e., the phase associated with circulating LP. It is possible that both pyrogenic metabolites are generated within the vascular compartment, reaching thermoregulatory centers of the brain by transfer across the blood-brain interface.  相似文献   
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823.
International Journal of Diabetes in Developing Countries -  相似文献   
824.
Chehab  FF; Der Kaloustian  V; Khouri  FP; Deeb  SS; Kan  YW 《Blood》1987,69(4):1141-1145
A study of the molecular lesions of beta-thalassemia in Lebanon revealed the presence of eight different mutations in 25 patients with Cooley's anemia. The IVS1 position 110 mutation predominated with a frequency of 62% and was almost invariably associated with Mediterranean chromosome haplotype I. Five other mutations commonly found in the Mediterranean area occurred with frequencies of 2% to 8%. In addition a G----C substitution in IVS1 position 5 (a lesion previously found in Chinese and Asian Indians) was demonstrated in a patient with Mediterranean haplotype IX. A new mutation at codon 29 was found in two other patients with haplotype II. The characterization of these beta-thalassemia mutations should allow the implementation of a prenatal diagnosis program in that country.  相似文献   
825.
Elbasvir (EBR; HCV NS5A inhibitor) and grazoprevir (GZR; HCV NS3/4A protease inhibitor) are approved as a fixed‐dose combination to treat patients chronically infected with HCV genotypes 1 and 4. During the development programme and supported by in vitro potency, the efficacy of EBR+GZR was assessed in HCV GT3‐infected patients. This study's aim was to determine the efficacy and tolerability of 12 or 18 weeks of EBR+GZR with ribavirin (RBV) in treatment‐naïve, noncirrhotic HCV GT3‐infected patients. Randomized patients received open‐label EBR (50 mg once daily) + GZR (100 mg once daily) + RBV. The primary efficacy objective was to evaluate the sustained virologic response rates 12 weeks after the end of all study therapy (SVR12). SVR12 rates (95% confidence interval) were 45.0% (23.1, 68.5) and 57.1% (34.0, 78.2) after treatment with EBR+GZR+RBV for 12 weeks or 18 weeks, respectively. On‐treatment virologic failure was observed in 41% (17 of 41) of patients. At virologic failure, resistance‐associated substitutions (RASs) with a >five‐fold shift in potency occurred in the NS3 region in six (35%) patients and in the NS5A region in 16 (94%) patients. The most common RAS at virologic failure was Y93H in NS5A which was identified in 13 of 17 (76%) patients. The efficacy of EBR+GZR+RBV was suboptimal in HCV GT3‐infected patients due to a high rate of on‐treatment virologic failure and treatment‐emergent RASs which demonstrates an inadequate barrier to the development of GT3 resistance. However, rapid viral clearance demonstrated the antiviral activity of EBR+GZR+RBV in GT3‐infected patients.clinicaltrials.gov: NCT01717326.  相似文献   
826.
PurposeTo describe a case of a young woman who presented for fertility preservation and underwent ovarian stimulation with an etonogestrel implant in place.MethodsA 24-year old, gravida 0, with an etonogestrel implant and newly diagnosed lower extremity sarcoma and DVT desiring oocyte cryopreservation prior to adjuvant chemotherapy and radiation. To avoid delay in her oncologic care and allow for continued use of contraception post-retrieval, the patient underwent controlled ovarian hyperstimulation (COH) without removal of the etonogestrel implant.ResultsBaseline labs included follicle-stimulating hormone 9 mIU/mL, luteinizing hormone 4.9 mIU/mL, estradiol 42 pg/mL, anti-Müllerian hormone 5.1 ng/mL, and antral follicle count greater than 40. The patient was placed on an antagonist protocol and stimulated with 125 IU Gonal-F and 75 IU Menopur. She received a total of 12 days of gonadotropin stimulation. On the day of trigger, her estradiol was 1472 pg/mL, lead follicle 21.5 mm with a total of 25 follicles measured > 12 mm. She was triggered with 5000 U hCG. She had a total of 23 oocytes retrieved, 17 of which were metaphase II and vitrified.ConclusionsCOH and successful oocyte cryopreservation can be achieved in patients with an etonogestrel implant in situ without apparent detrimental effects to oocyte yield or maturity. Due to the etonogestrel implant’s inhibitory effects on LH, it is recommended to use an hCG trigger for final oocyte maturation.  相似文献   
827.
828.
Idiopathic hypogonadotrophic hypogonadism (IHH) is a potentially correctable cause of male infertility. However hormonal treatment is usually a slow process and artificial reproductive techniques such as intracytoplasmic sperm injection (ICSI) might be resorted to before full testicular response has been achieved. We report here an unusual variant of IHH of post-pubertal onset in which early intervention with ICSI was attempted. Our patient was 37 years old and presented with male infertility due to azoospermia and undetectable serum gonadotrophin concentrations. He had an apparently normal pubertal development, a testicular volume of 8 ml, normal pituitary-thyroid and pituitary-adrenal function, as well as normal computerized tomographic appearance of the sella region. A combination of human chorionic gonadotrophin (HCG) and menopausal gonadotrophins (HMG) was administered. Spermatozoa were first detected in the semen after 3 months and reached a concentration of approximately 2x10(6)/ml after 9 months. ICSI was attempted at this point; the spermatozoa had good fertilizing ability and three embryos were obtained and replaced. Unfortunately no pregnancy resulted. Treatment with 5000 IU HCG and 150 IU HMG three times per week was continued and sperm counts rose rapidly thereafter to reach 28.3x10(6)/ml after 16 months of injections. His wife conceived naturally during this period and the pregnancy is now in the second trimester. This case illustrates the good prognosis of the rare patient with IHH of post-pubertal onset when treated with gonadotrophins, and suggests that ICSI procedures should be delayed until final testicular maturation is attained.   相似文献   
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830.
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