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31.
External cephalic version has been used periodically for centuries to manage breech presentations. As cesarean section rates have escalated in the last two decades, ways to curb this rise have been evaluated. By reducing the number of infants that arrive in labor in a representation, it is possible to impact the overall cesarean section rate. External cephalic version is a safe, effective method when used in appropriate cases of breech presentation. A forward or backward roll can be accomplished in women at term with singleton gestations, adequate amniotic fluid, and reactive nonstress tests. Parity, fetal and placental position, and descent of the presenting part may all influence the success rate of the version.  相似文献   
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The effect of human recombinant interleukin-2 (IL-2) and human recombinant granulocyte-macrophage colony-stimulating factor on the growth of a virulent strain of Escherichia coli in tissue culture medium and in untreated, normal mouse serum was investigated. Both of these cytokines enhanced the growth of the microorganism two- to threefold in tissue culture medium with or without additional fetal calf serum and in untreated mouse serum. IL-4 did not have any effect on the growth of this microbe under the conditions tested. That the enhancement of growth seen with recombinant IL-2 was due to the active cytokine was shown by the following data: (i) addition of an antibody to IL-2 abrogated the growth-promoting effect; (ii) the excipient buffer, which contained everything except the active cytokine, was inactive in modifying bacterial growth; and (iii) heat-inactivated recombinant IL-2 did not promote enhanced microbial growth. The enhancement of growth with IL-2 was significant with concentrations as low as 1 U/ml. Growth of an avirulent strain of E. coli was not stimulated by IL-2. Moreover, addition of IL-2 to growth virulent E. coli in tissue culture medium led to rapid removal of the cytokine from the medium. Collectively, these data suggest that cytokines may act as growth factors for some virulent bacteria.  相似文献   
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The diffusion of ofloxacin in infected and healthy human and rabbit eyes was investigated. In the human study, cataract surgery patients were given intravenous ofloxacin either as a single 200 or 400 mg dose or as two 400 mg infusions 12 hours apart. Samples of aqueous humor and plasma were collected between 1 and 12 hours after the end of the infusion. Levels in the anterior chamber increased with the dose; peak levels, which occurred after three hours, were 0.33 mg/l after 200 mg and 1.24 mg/l after two 200 mg doses given 12 hours apart. In the rabbit study, 16 hours after experimental infection of the left eye by injection of S. epidermidis into the vitreous, animals were given an intraperitoneal injection of 20 or 50 mg/kg ofloxacin. Dosages in the various ocular tissues showed that penetration into the eye varied with race (albinos greater than pigmented) and dose. Intraocular ofloxacin levels, including in the vitreous, increased two fold when the eye was infected; however, penetration into the sclera, choroid, and retina was comparable in infected and noninfected eyes. These findings in humans and animals suggest that ofloxacin in a dose of a least 400 mg is a useful agent for the treatment of prophylaxis of ocular infections.  相似文献   
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Sixty-seven patients with advanced carcinoma of the lower female genital tract (cervix, vagina, and vulva) were treated with radiation and concomitant intravenous cisplatin and/or 5-fluorouracil. Fifty-seven patients (85%) responded completely clinically. Thirty-five (61%) complete responders recurred with a median time to recurrence of 6 months. Twenty-six of the thirty-five patients who recurred had some component of local failure. The 22 complete responders who have not recurred have been followed a median of 13 months. Acute toxicity was minimal, with only 6 patients requiring interruption of therapy. Nine (13%) patients developed severe late complications and eight required surgery. The actuarial 5-year survival is 22%. This treatment regimen is disappointing in terms of both survival and local control.  相似文献   
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Thirty-seven DR4-positive patient-unrelated bone marrow donor pairs previously DR/DQ restriction fragment length polymorphism (RFLP) typed and tested in mixed lymphocyte culture (MLC), have been DR4-Dw subtyped retrospectively using sequence specific oligonucleotide probes. We found that DR4-Dw subtyping substantially increased the accuracy of pre-MLC matching and could potentially accelerate donor searches by avoiding unnecessary MLC tests on Dw-mismatched donors.  相似文献   
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Background: During labor, ephedrine is widely used to prevent or to treat maternal arterial hypotension and restore uterine perfusion pressure to avoid intrapartum fetal asphyxia. However, the effects of ephedrine on uterine blood flow have not been studied during uterine contractions. The purpose of the study was to assess the effects of ephedrine on uterine artery velocities and resistance index using the Doppler technique during the active phase of labor.

Methods: Ten normotensive, healthy parturients with uncomplicated pregnancies at term received intravenous ephedrine during labor to increase mean arterial pressure up to a maximum of 20% above their baseline pressure. Peak systolic and end-diastolic Doppler flow velocities and resistance indices were measured in the uterine artery before and immediately after administration of bolus intravenous ephedrine and after ephedrine washout. Umbilical and fetal middle cerebral arterial resistance indices and fetal heart rate were also calculated.

Results: After ephedrine administration, mean arterial pressure increased by 17 +/- 4%. End-diastolic flow velocity in the uterine artery at peak amplitude of uterine contraction was restored to 74% of the value observed in the absence of contraction. The systolic velocity was totally restored, and the uterine resistance index was significantly decreased, compared with the values in the absence of contraction. Between uterine contractions, ephedrine induced similar but less marked effects. Fetal hemodynamic parameters were not altered by ephedrine administration.  相似文献   

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