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991.
This article provides an overview of medication abortion in the United States 6 years after the approval of mifepristone (RU486; Mifeprex; Danco Laboratories, LLC, New York, NY) by the US Food and Drug Administration (FDA). The adoption of mifepristone is considered in the context of epidemiologic data on abortion, abortion access, and the safety of abortion. The risks of medication and aspiration abortion are discussed in the context of abortion-related mortality, recent experience with obstetric and gynecologic infection with Clostridium sordellii, and the limits of scientific knowledge on the incidence of this infection in women. Innovative protocols studied since FDA approval of mifepristone are presented, and implications for clinical practice are discussed.  相似文献   
992.
Horner syndrome     
Horner syndrome is an uncommon but important clinical entity, representing interruption of the sympathetic pathway to the eye and face. Horner syndrome is almost always diagnosed clinically, though pharmacological testing can be used to confirm the diagnosis. Imaging modalities such as PET, CT and MRI are important components of work‐up for patients presenting with acquired Horner syndrome. Our patient’s presentation with Horner syndrome unmasked the causative superior sulcus squamous cell carcinoma and a coincidental lower lobe adenocarcinoma. Successful radical treatment of these cancers resulted in complete resolution of the syndrome and disease‐free survival at 18 months. We review the anatomy and pathophysiology underlying this and other causes of Horner syndrome.  相似文献   
993.
Summary Co-dergocrine has recently been demonstrated acutely to lower plasma norepinephrine (NE) and blood pressure (BP) in patients with essential hypertension, and similar results have been obtained during chronic administration of co-dergocrine to healthy men. The present study investigated the effect of 3 weeks of treatment with co-dergocrine 4 mg/day on BP, plasma catecholamines, certain other BP-regulating factors and serum lipoproteins in patients with essential hypertension. Compared to placebo conditions, co-dergocrine decreased supine BP and heart rate by −7% and the upright plasma NE level by −24%. Supine plasma NE also fell (−24%). Total cholesterol and the LDL + VLDL-cholesterol lipoprotein fraction were lowered by −6%. No significant change was observed in plasma renin activity, angiotensin II, aldosterone and epinephrine levels, whole blood and plasma volume, exchangeable sodium, and the cardiovascular responsiveness to NE, angiotensin II and isoproterenol. The findings suggest that in patients with essential hypertension, chronic treatment with co-dergocrine may slightly decrease sympathetic outflow and, at least in the short-term, lower the potentially atherogenic serum LDL + VLDL − cholesterol fraction.  相似文献   
994.
以23例肾功能不全与20例肾功正常患者的唾液尿素氮、钠、钾、舌面pH值和血液的相应生化检查作对照。结果唾液尿素氮、钾与血尿素氮、钾成正相关性。证实了中医“津血同源”“肾为唾”的理论。  相似文献   
995.
668颗后牙镍铬合金PFM边缘适合性的临床观察   总被引:4,自引:0,他引:4  
目的:观察采用2种边缘形式的后牙烤瓷熔附金属全冠边缘适合性和对牙龈健康的影响.方法:对668颗后牙,分别采用2种边缘形式的后牙烤瓷熔附金属全冠(单冠或桥的基牙)在修复2年后进行复查,检测其边缘适合性及牙龈指数(GI)和牙周探诊深度(PD),用统计学方法分析修复体边缘形式与牙龈病变间的关系.结果:采用羽状边缘360°金属脚边的PFM边缘适合性明显优于凹面肩台型边缘PFM,凹面肩台型边缘的PFM的牙龈病变发生率,明显高于羽状边缘360°金属脚边的PFM,而边缘适合性差者较适合性好者牙龈病变发生率显著增高.结论:后牙PFM的边缘采用羽状边缘360°金属脚边是一种好的选择.  相似文献   
996.
997.
Structure and permeability of the ependymal lining the infundibular recess were studied in perinatal rats with silver impregnation, electron microscopy, radioautography, and tracer techniques. According to our data basal processes of ependymal cells reach the primary portal plexus linking the 3rd ventricle and the hypophysial portal system all through the perinatal period. After birth, some of the processes penetrate into the perivascular space of the primary portal plexus and abut there on the endothelium of capillaries. Ependymal cells of fetuses and neonates are joined by specialized junctions (tight junctions, gap junctions and zonulae adhaerentes). Intraventricularly injected ionic lanthanum crosses the ependymal lining of fetuses both trans- and extra-cellularly everywhere in the infundibular recess. By postnatal day 9 only the rostral portion of the recess remains readily permeable. Caudally, extracellular leakage becomes highly restricted, apparently due to the appearance of circumferential tight junctions. Finally, [3H]dopamine seems to penetrate through the ependymal lining in the same way as ionic lanthanum entering the portal capillaries. These findings suggest that the adenohypophysiotropic neurohormones can penetrate from the cerebrospinal fluid into the portal circulation from the very beginning of the establishment of the hypothalamo-hypophysial functional relationships during ontogenesis.  相似文献   
998.
N-(Acetoxyethoxycarbonyl) derivatives of primary amines released a major fraction of the parent amine in the desired free form in plasma but a significant fraction of the undesired N-acetylated parent amine was also produced. The fraction of the parent amines released from the carbamate derivatives of the primary amines was greater in human plasma than in pH 7.4 buffer. In human plasma, the N-(acetoxyethoxycarbonyl) derivative of a secondary amine released the parent amine in a quantitative manner at a rate higher than that observed in pH 7.4 buffer. Experimental results suggested that the observed catalysis of the release of the parent amines from N-(acetoxyethoxycarbonyl) derivatives of primary and secondary amines was due to participation by plasma esterases. The data suggested that N-(acetoxyethoxycarbonyl) derivatives are well suited for use as prodrugs of secondary amines. Their utility as prodrugs of primary amines is more problematic and cannot be predicted prior to in-vivo studies for the individual compound.  相似文献   
999.
Zusammenfassung Es wird über einige Fälle mit Stichverletzung von Schädel und Gehirn berichtet, diagnostische Probleme werden angesprochen. Die Verletzungen werden oft verkannt, weil die äußere Wunde nicht selten harmlos aussieht, keine neurologische Symptomatik vorliegt oder weil klinische Symptome als Folge von Trunkenheit, stumpfem Trauma oder einer Erkrankung interpretiert werden. Die Wichtigkeit einer genauen Untersuchung des Kopfes des Patienten — auch mit der verfeinerten Technik der modernen Radiodiagnostik — wird betont; denn bei richtiger Diagnose in angemessener Zeit ist die Prognose nicht immer schlecht.  相似文献   
1000.
Neuron-enriched cultures derived from 6-day-old chick embryo cerebral hemispheres were treated with morphine or methadone, 10(-5) M or 10(-6) M, on days 4-6 or 6-8 in culture and were evaluated morphologically and biochemically at day 9 using phase contrast microscopy and choline acetyltransferase activity (ChAT) as a cholinergic marker. The treatment of the cultures with morphine markedly affected their growth pattern; specifically, we observed an increased number of flat cells presumptively glia, and aggregates sided by flat cells and devoid of thick bundles of neuritic processes that normally characterize neuron-enriched cultures. These morphologic changes were reflected in a drastic decrease of ChAT activity in cultures treated from day 4 to day 6 but not from 6 to 8. In contrast to morphine, exposure to 10(-6) M methadone from day 4 to day 6 resulted in reduced ChAT activity but the growth pattern of the cultures remained morphologically intact. We suggest that morphine exerts a general neurotoxic effect whereas methadone may affect some specific cholinergic function.  相似文献   
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