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21.
EDITORIAL COMMENT: In medicine, human judgment is fallible, but obstetrics is the discipline in which an error of judgment is most rapidly revealed, to the obstetrician, the patient and the labour ward staff, due to the unpredictability of the duration of labour and imminence of delivery in any individual patient. When the editor was a house officer he was called to the antenatal ward because a multipara, near term had abdominal pain. Vaginal examination revealed an undiluted cervix, but within the minute or so it took a walk to the handbasin to wash his hands the woman had delivered a live baby into the bed. It is always wise, and should be a routine. unless operating in haste for an emergency such as bleeding from placenta praevia, to perform a vaginal examination after anaesthesia is established before commencing Caesarean section in a woman in labour. The editor has performed many safe easy-forceps deliveries in this circumstance, in theatre, in women in whom Caesarean section was planned for cephalopelvic disproportion with or without fetal distress. This finesse is more important if the consultant has agreed to perform a Caesarean on the findings recorded by others, but the fact remains that labour and delivery can accelerate most unexpectedly. We accepted this case report for publication, not merely because it is the first such case reported, but also for the opportunity it provided to stress to readers the need for final evaluation of the stage of labour before Caesarean section, when the conditions are most favourable for assessment. Nonetheless, as this case tells us. it is possible for labour and delivery to proceed faster than the obstetrician can perform a Caesarean section.  相似文献   
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A co-operative study was conducted to determine the clinical characteristics of patients with moyamoya disease who were diagnosed and treated at neurosurgical institutes in Korea before 1995. Twenty-six hospitals contributed 505 cases and among them, the clinical characteristics of 334 patients with definite moyamoya disease were evaluated. The number of patients began to increase from the late 1980s, and after that approximately 20 patients were treated each year. There were two age peaks: from six to 15 and from 31 to 40 years of age. Haemorrhagic manifestations occurred in approximately 43% of the patients. The major clinical manifestations were haemorrhage in adults (62.4%) and ischaemia in children (61.2%). Overall 54.5% of the patients experienced decreased consciousness levels, mainly due to intracranial haemorrhage or cerebral infarction. In the patients with ischemic manifestations, the adult patients were more likely to have cerebral infarction than the pediatric patients (80% vs. 39%) and the pediatric patients were more likely to have TIA (61% vs. 25%). Thirty eight percent of the patients underwent bypass surgery and 53% of these procedures were performed bilaterally. Treatment policies, including indications for bypass surgery and commonly used drugs, were somewhat different according to the institution. Overall favorable outcome was 73%, and the most significant factor affecting poor outcome was haemorrhagic manifestation. This article describes the characteristics of 334 patients with moyamoya disease, who were diagnosed and treated at neurosurgical institutes in Korea before 1995.  相似文献   
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Background: Aggravated melasma after treatment is vulnerable to stimulation, can easily deteriorate, and may be distressing without proper management. Objective: To retrospectively assess the effectiveness and safety of combination therapy using low-fluence Q-switched neodymium-doped yttrium aluminum garnet (Nd:YAG) laser (QSNY) and long-pulse Nd:YAG laser (LPNY) (dual toning) in patients with rebound melasma. Materials and methods: A total of 30 patients with aggravated melasma after previous therapy who were treated with dual toning were enrolled. A total of 10 sessions were conducted at 1-week intervals, followed by maintenance treatment. The results were evaluated using the modified Melasma Area and Severity Index (mMASI) and the physician's global assessment (PGA) before and 2 months after completing the 10 treatment sessions. Results: The baseline mMASI was 10.48 ± 3.64, which significantly decreased to 3.22 ± 1.45 2 months after completing the 10 treatment sessions (p < 0.001). Twenty-four patients (80%) had PGA grade 4 (76–100% improvement) and 6 patients (20%) had PGA grade 3 (51–75% improvement). Conclusion: Dual toning may be a safe and effective salvage treatment for patients with aggravated melasma after previous treatment. LPNY may stabilize melasma activity to prevent rebound hyperpigmentation via dermal remodeling.  相似文献   
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Nematodes use an extensive chemical language based on glycosides of the dideoxysugar ascarylose for developmental regulation (dauer formation), male sex attraction, aggregation, and dispersal. However, no examples of a female- or hermaphrodite-specific sex attractant have been identified to date. In this study, we investigated the pheromone system of the gonochoristic sour paste nematode Panagrellus redivivus, which produces sex-specific attractants of the opposite sex. Activity-guided fractionation of the P. redivivus exometabolome revealed that males are strongly attracted to ascr#1 (also known as daumone), an ascaroside previously identified from Caenorhabditis elegans hermaphrodites. Female P. redivivus are repelled by high concentrations of ascr#1 but are specifically attracted to a previously unknown ascaroside that we named dhas#18, a dihydroxy derivative of the known ascr#18 and an ascaroside that features extensive functionalization of the lipid-derived side chain. Targeted profiling of the P. redivivus exometabolome revealed several additional ascarosides that did not induce strong chemotaxis. We show that P. redivivus females, but not males, produce the male-attracting ascr#1, whereas males, but not females, produce the female-attracting dhas#18. These results show that ascaroside biosynthesis in P. redivivus is highly sex-specific. Furthermore, the extensive side chain functionalization in dhas#18, which is reminiscent of polyketide-derived natural products, indicates unanticipated biosynthetic capabilities in nematodes.  相似文献   
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