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31.
ABSTRACT: Background: Most women will sustain some degree of trauma to the genital tract after vaginal birth. This study aimed to examine the association between maternal position at birth and perineal outcome in women who had a midwife‐attended, spontaneous vaginal birth and an uncomplicated pregnancy at term. Methods: Data from 3,756 births in a major public tertiary teaching hospital were eligible for analysis. The need for sutures in perineal trauma was evaluated and compared for each major factor studied (maternal age, first vaginal delivery, induction of labor, not occipitoanterior, use of regional anesthesia, deflexed head and newborn birthweight >3,500 g). Birth positions were compared against each other. Subgroup analysis determined whether birth positions mattered more or less in each of the major factors studied. The chi‐square test was used to compare categorical variables. Results: Most women (65.9%) gave birth in the semi‐recumbent position. Of the 1,679 women (44.5%) who required perineal suturing, semi‐recumbent position was associated with the need for perineal sutures, whereas all‐fours was associated with reduced need for sutures; these associations were more marked in first vaginal births and newborn birth weight over 3,500 g. When regional anesthesia was used, semi‐recumbent position was associated with a need for suturing, and lateral position associated with a reduced need for suturing. The four major factors significantly related to perineal trauma included first vaginal birth, use of regional anesthesia, deflexed head, and newborn weight more than 3,500 g. Conclusions: Women should be given the choice to give birth in whatever position they find comfortable. Maternity practitioners have a responsibility to inform women of the likelihood of perineal trauma in the preferred birth position. Ongoing audit of all clinicians attending births is encouraged to further determine effects of maternal birth position and perineal trauma, to investigate women's perception of comfortable positioning at birth, and to measure changes to midwifery practice resulting from this study.  相似文献   
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1. Opioid receptors have been localised on sensory fibres in the vagus nerve and opioids have previously been shown to inhibit non-adrenergic, non-cholinergic (NANC) neurotransmission in guinea-pig bronchi in vitro and in vivo. We have now investigated whether an inhibitory effect could be demonstrated on cholinergic neurotransmission. 2. Electrical field stimulation (EFS) (8 Hz, 0.5 ms, 40 V for 20 s) produced only a rapid, cholinergic response in the upper trachea but in the lower trachea and main bronchi a cholinergic response which was atropine-sensitive and a longer lasting NANC contraction that was atropine-insensitive was demonstrated. This slow contraction could be blocked by tetrodotoxin and capsaicin pretreatment. 3. [D-Ala2, NMePhe4, Gly-ol5]enkephalin (DAMGO), a selective mu-opioid receptor agonist, inhibited the cholinergic response to EFS at 8 Hz in a dose-dependent manner in main bronchi (IC50 = 113 nM with a maximal inhibition of 35.7 +/- 5.6% 10 microM, n = 5). In the lower trachea, DAMGO inhibited the cholinergic response to a similar extent (inhibition of 35.8 +/- 3.5% at 10 microM, n = 5). However, DAMGO had no effect on the contractile response to exogenously applied acetylcholine in the main bronchi. By contrast, opioids had no inhibitory effect on cholinergic neurotransmission in the upper trachea. DAMGO (1 microM) inhibited the cholinergic response to EFS in a frequency-dependent manner in the main bronchi with greater inhibition at lower frequencies of stimulation.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
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Syntheses of several tripeptide analogues of leupeptin containing C-terminal argininal, lysinal, or ornithinal units are presented. The synthetic analogues were tested as inhibitors of trypsin, plasmin, and kallikrein. (Benzyloxycarbonyl)-L-leucyl-L-leucyl-L-argininal (2a) was significantly less effective as an inhibitor of trypsin and plasmin activity than leupeptin. (Benzyloxycarbonyl)-L-leucyl-L-leucyl-L-lysinal (2e) and (benzyloxycarbonyl)-L-leucyl-L-leucyl-L-ornithinal (2i) display different inhibition characteristics than (benzyloxycarbonyl)-L-leucyl-L-leucyl-L-argininal (2a). While (benzyloxycarbonyl)-L-leucyl-L-leucyl-L-argininal (2a) showed moderate inhibition of all three enzymes tested, (benzyloxycarbonyl)-L-leucyl-L-leucyl-L-lysinal (2e) was less effective as an inhibitor of trypsin and plasmin activity. Of the three enzymes tested, (benzyloxycarbonyl)-L-leucyl-L-leucyl-L-ornithinal (2i) showed significant inhibition of kallikrein activity only. Modifications made in the composition and sequence of the P2 and P3 amino acids also resulted in variations in the inhibitory activity of the analogues. In general, plasmin showed a strong preference for inhibitors which contain an L-phenylalanyl-L-leucyl or an L-leucyl-L-valyl unit in the P2 and P3 positions.  相似文献   
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J M Goldman  D J Barnes    D V Pohl 《Thorax》1990,45(1):76
A case of obstructive sleep apnoea is reported that was caused by a dermoid cyst of the floor of the mouth and cured by surgery.  相似文献   
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Summary The glycosphingolipid galactosylceramide (GalCer) has been identified as an alternate receptor for the human immunodeficiency virus type 1 (HIV-1). Here we review a liposome flotation assay used to study the interaction of the HIV-1 envelope glycoprotein (env) with artificial membrane vesicles containing GalCer. The properties of binding, the nature of the env binding site for GalCer, and the implications of this interaction for HIV-1 infection are discussed.  相似文献   
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There is little agreement about the methodology of clinical trials of antipsychotic drugs in patients with negative symptoms. A literature review revealed wide variation in experimental design, rating scales and study duration. This reflects differing views as to the definition and response to treatment of negative symptoms. Some degree of standardization would improve comparability of studies and aid the development of new compounds. Patients included in such studies should have displayed negative symptoms for at least 6 months. Depressive symptoms, positive schizophrenic symptoms and extrapyramidal signs may all influence or be confused with negative symptoms and may respond to treatment; they should be at a low level at baseline and should be measured during the study period. Studies should last at least 8 weeks. Several scales are available for measuring negative symptoms and are reviewed; a global impression score should be used additionally.  相似文献   
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