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81.
The cyclic vomiting syndrome is defined by episodes of vomiting lasting from hours to days with free intervals between episodes. Various symptoms can be associated with vomiting: nausea, abdominal pain, photophobia, fever, pallor, dehydratation, excess salivation, social withdrawal. Some factors often precipitate the crisis: infection, psychological stresses, menstruation. Excluding a medical condition, especially a gastro-intestinal or a neurological disease is compulsory for the diagnostic of cyclic vomiting syndrome. The cyclic vomiting syndrome shares many common features with migraine including treatment. Due to negative paraclinical testing, a psychiatric disease is often suspected in these children. Pathophysiology of cyclic vomiting syndrome is unknown. As for migraine, mitochondrial and ionic channels abnormalities are thought to play a role. Overactivation of hypothalamic-pituitary-adrenal axis and autonomic dysfunction seem to be involved too. Three clinical vignets will illustrate these aspects. 相似文献
82.
Effects of different cellulose derivatives on drug release mechanism studied at a preformulation stage. 总被引:2,自引:0,他引:2
O Chambin D Champion C Debray M H Rochat-Gonthier M Le Meste Y Pourcelot 《Journal of controlled release》2004,95(1):101-108
As a matter of fact, in vitro dissolution is well known to be the method of choice for the pharmaceutical industry to develop effective medicines. However, many experiments must be performed all along a new product life and they represent an overcharge of work for researchers. The purpose of this paper was to assess the relevance of new parameters obtained during preformulation stage by Nuclear Magnetic Resonance (NMR) experiments to better understand drug release mechanism. This study was carried out with three cellulose derivatives currently used as carrier matrices (Microcrystalline cellulose (MCC), Hydroxypropylmethyl cellulose (HPMC) and Ethyl cellulose (EC)). Granules and tablets were produced with these three excipients (60% w/w) and theophylline as drug model (40%). On the one hand, in vitro dissolution studies were performed with the rotating paddle method displaying the different release behaviour of these three matrices (immediate release for MCC, steady release for HPMC and sustained release for EC). On the other hand, the evolution of the T2m spin-spin relaxation time in NMR experiments during granules hydration was recorded. NMR findings shore up dissolution data, both depending on interactions between the matrix and water. NMR spectroscopy appears to be a valuable tool for obtaining, at an earlier stage of drug development, more information about drug release mechanism. 相似文献
83.
G G Varela A López-Loredo J F García León 《JSLS, Journal of the Society of Laparoendoscopic Surgeons》2007,11(1):127-130
BACKGROUND AND OBJECTIVE: We present the case of a female patient 29 years of age with antecedents of laparoscopic laser ablation for endometriosis, laparoscopic appendectomy, and umbilical hernioplasty. METHODS: The patient was admitted to the hospital's emergency room for abdominal pain in the epigastrium, transfixing, irradiating to both upper quadrants and to the lumbar region, accompanied by nausea and gastrobiliary vomiting. Lipase determination was 170 mg/dL. Other laboratory findings were normal. Plain abdominal films on the patient's admission were normal, and computed tomography (CT) showed data compatible with acute pancreatitis. Without improvement during the patient's hospital stay, pain and vomiting increased in intensity and frequency. RESULTS: New abdominal x-rays revealed dilatation of small bowel loops. Management was begun for intestinal obstruction, with intravenous hydration and placement of a nasogastric tube without a good response. At 48 hours, a diagnostic laparoscopy was performed, revealing a 3-cm internal hernia in the left broad ligament in which a 20-cm segment of terminal ileum was encased. We performed liberation of the ileal segment and closed the hernial orifice by using the laparoscopic approach. CONCLUSION: The patient's evolution was excellent. 相似文献
84.
Thellea K. Leveque Le Yu David C. Musch Ronald D. Chervin David N. Zacks 《Sleep & breathing》2007,11(4):253-257
Patients with obstructive sleep apnea (OSA), in comparison to controls, have increased levels of circulating epinephrine and
norepinephrine, both of which are risk factors for the development of central serous chorioretinopathy (CSCR). The aim of
this pilot study was to investigate the frequency of symptoms that suggest OSA in CSCR patients and normal controls. The Berlin
Questionnaire, a validated research tool to assess risk for OSA, was administered to 29 patients who met the criteria for
active, acute, non-steroid-induced CSCR and 29 controls matched for age and sex. In this retrospective case-controlled study,
the main outcome measure was increased risk for OSA. The mean age of the patients was 47.8 years (range 29–72) and the mean
age of controls was 47.3 years (range 25–70). Seventy-six percent (22) of both groups were men. Survey scores showed 58.6%
(17) of patients with CSCR to be at an increased risk for OSA compared to 31.0% (nine) of controls. A conditional logistic
regression analysis showed that the CSCR group had a higher proportion with an increased risk for OSA compared to the control
group (odds ratio=3.67; 95% CI: 1.02, 13.14; P = 0.046). Patients with CSCR may be more likely than other adults to have OSA, and screening for this sleep disorder should
be considered in this population. Further research is warranted to determine whether sleep apnea may contribute to the development
of CSCR, and to assess whether treatment of sleep apnea might offer a new therapeutic option for some patients with CSCR. 相似文献
85.
86.
87.
Prospective study of the occurrence of monoclonal gammapathies following bone marrow transplantation in young children 总被引:2,自引:0,他引:2
We have prospectively studied the occurrence of monoclonal serum immunoglobulins in 38 recipients of BMT. Patients were young children with primary immunodeficiencies (n = 31), other inherited diseases (n = 4), leukemia (n = 2), or aplastic anemia (n = 1). Twenty-nine received an HLA-nonidentical marrow and nine an HLA-identical marrow. Serum monoclonal immunoglobulins were detected by the immunofixation method. Monoclonal immunoglobulins were found in 26 patients. Monoclonal components were more frequently detected in patients with primary severe T cell deficiencies (21/25) rather than in the other patients (6/13). In 7 of 29 recipients of HLA-nonidentical transplants, versus 0 out of 9 recipients of HLA-identical transplants, serum monoclonal immunoglobulins were found associated with a B lymphocyte proliferation syndrome due to an Epstein-Barr virus infection. In this group, monoclonal immunoglobulins were detected early, prior to the onset of the clinical syndrome. The simultaneous occurrence of several monoclonal immunoglobulins was more frequent in these patients, while monoclonal immunoglobulin concentrations increased faster, especially those of IgM isotype. These characteristics may allow in patients at risk (recipients with primary T cell immunodeficiencies and receiving HLA-nonidentical transplantation) an earlier diagnosis of B lymphocyte proliferative syndrome that may eventually lead to early and more efficient therapy. 相似文献
88.
89.
D Komiotis C T Lim J P Dieter G C Le Breton D L Venton 《Journal of medicinal chemistry》1992,35(16):3033-3039
Previous observations implicating PgH2 as a direct activator of platelets suggested that derivatives of U46619, a well-characterized TxA2 receptor agonist having structural homology with PgH2, might possess antiplatelet activity. The present work describes the synthesis of [1S-(1 alpha,2 beta,3 alpha,4 alpha)]-3-[(tetrahydropyranyloxy)methyl]- 2-[2-[(triphenylmethyl)oxy]ethyl]-5-oxabicyclo[2.2.1]heptane (14) a potentially useful intermediate for the synthesis of various epoxymethano derivatives. The latter was converted to [1S-(1 alpha,2 beta (Z),3 alpha,4 alpha)]-7-[3-[[2- [(phenylamino)carbonyl]-hydrazino]methyl]-5-oxabicylo[2.2.1]hept-2 - yl]-5-heptenoic acid (23), an epoxymethano derivative of PgH2 containing a hydrazide lower side chain as previously used in the TxA2 antagonist, SQ 29,548. The intermediate 14 was also converted to [1S-(1 alpha,2 beta (Z),3 alpha,4 alpha)]-7- [3-[(hexylamino)methyl]-5-oxabicyclo[2.2.1]hept-2-yl]-5-heptenoic acid (25) which contained a simple aza side chain as used in earlier antagonists. Derivatives 23 and 25 appeared to be specific antagonists of the human platelet TxA2 receptor as evidenced by their inhibition of U46619 (1.5 microM) induced aggregation of human platelet rich plasma (IC50 = 22 and 7 microM, respectively), while having little effect on ADP (2 microM) induced aggregation at much higher concentrations. In addition, one of these derivatives, the bicycloamine 25, was shown to compete for [3H]U46619 binding to washed human platelets with an IC50 value of 25 microM, supporting the notion that these derivatives were acting at the thromboxane receptor. However, the potency of these derivatives was less than for previously reported TxA2 antagonists, suggesting that simple linear combinations of functionality from molecules active at the human platelet thromboxane receptor will be of limited predictive value. 相似文献
90.
乳腺癌患者血中角蛋白mRNA基因的表达 总被引:1,自引:0,他引:1
目的 分析乳腺癌患者外周血液中角蛋白(CK19)mRNA基因的表达。方法 取20例经病理证实的乳腺癌患者外周血,用Tirizol法提取总RNA,然后进行RT-PCR荧光定量检测,并与正常人群进行对照。结果 正常人群外周血中无CK19表达,20例乳腺癌中有6例阳性表达,总阳性率为29.65%,其中单纯癌阳性率为30.7%(4/13),浸润性导管癌阳性率为28.6%(2/7)。结论 CK19可作为检测外周血循环癌细胞的标志物。 相似文献