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81.
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Heterotopic pregnancy has been traditionally considered a rare event; however, with the use of assisted reproductive technology, the incidence of heterotopic pregnancies is increasing. Diagnosing a heterotopic pregnancy can be challenging. This report describes a 30-year-old female at 11 weeks' gestation with an intrauterine twin pregnancy after gonadotropin stimulation and intrauterine insemination who presented complaining of left lower quadrant abdominal pain with constipation and cramps. The patient was empirically treated for diverticulitis but failed to respond to therapy. A heterotopic triplet pregnancy was ultimately diagnosed at laparoscopy. Heterotopic pregnancy must be considered in the differential diagnosis of abdominal pain in the first trimester, especially in patients who conceived by means of assisted reproductive technology. Surgical treatment is the most frequently used method of treatment.  相似文献   
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Evidence demonstrating that the neuroendocrine system (brain, corpus cardiacum, and corpus allatum) of the tobacco hornworm, Manduca sexta (L.), contains a peptide that is gastrin-like in its antigenicity, size, and susceptibility to degradative enzymes is presented. No immunoreactive gastrin was found in gut extracts from four species of insects. These results suggest the existence of a peptide in insect nervous tissue having structural similarities to vertebrate gastrin.  相似文献   
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Pharmacological studies suggest a role for CB1 cannabinoid receptors (CB1R) in regulating neurogenesis in the adult brain. To investigate this possibility, we measured neurogenesis by intraperitoneal injection of bromodeoxyuridine (BrdU), which labels newborn neurons, in wild-type and CB1R-knockout (CB1R-KO) mice. CB1R-KO mice showed reductions in the number of BrdU-labeled cells to approximately 50% of wild-type (WT) levels in dentate gyrus and subventricular zone (SVZ), suggesting that CB1R activation promotes neurogenesis. To test this further, WT mice were given the CB1R antagonist N-(piperidin-1-yl)-5-(4-chlorophenyl)-1-(2,4-dichlorophenyl)-4-methyl-1H-pyrazole-3-carboximide hydrochloride (SR141716A) before measuring neurogenesis with BrdU. SR141716A paradoxically increased the number of BrdU-labeled cells by approximately 50% in SVZ; another CB1R antagonist, 1-(2,4-dichlorophenyl)-5-(4-iodophenyl)-4-methyl-N-1-piperidinyl-1H-pyrazole-3-carboxamide (AM251), had a similar effect. To investigate this discrepancy, SR141716A was given to CB1R-KO mice, in which it still stimulated neurogenesis, indicating involvement of a non-CB1 receptor. Action at one such non-CB1, SR141716A-sensitive site, the VR1 vanilloid receptor, was tested by administering SR141716A to VR1-KO mice, in which the ability of SR141716A to enhance neurogenesis was abolished. Thus, CB1 and VR1 receptors both seem to have roles in regulating adult neurogenesis.  相似文献   
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BACKGROUND: The effect of Helicobacter pylori in provoking or protecting against gastro-oesophageal reflux disease is unclear and studies have given conflicting results. Recent guidelines recommend H. pylori eradication in patients on long-term proton pump inhibitors. AIM: To ascertain the effect of H. pylori eradication on gastro-oesophageal reflux disease outcomes (reflux oesophagitis and heartburn) in patients with duodenal ulcer disease, and to ascertain the effect of H. pylori infection on reflux oesophagitis concerning heartburn, pH, severity, healing and relapse rates. METHODS: A systematic review of electronic databases was undertaken to September 2003. Experts in the field, pharmaceutical companies and journals were contacted about unpublished trials. Studies were reviewed according to predefined eligibility and quality criteria. Twenty-seven studies/trials were included in the systematic review. RESULTS: Study variation rather than therapy-influenced results in relation to the presence or absence of oesophagitis in patients with duodenal ulcer who underwent H. pylori eradication at 6-48 months follow-up. In patients with reflux oesophagitis no obvious differences were discovered in heartburn scores, 24-h pH values, healing and relapse rates between H. pylori-positive and -negative cases. CONCLUSION: There is no evidence to indicate that H. pylori eradication in duodenal ulcer disease provokes reflux oesophagitis or worsens heartburn; (ii) there are insufficient data to draw firm conclusions about the impact of H. pylori in patients with reflux oesophagitis.  相似文献   
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The study sought to evaluate the response to cyclophosphamide (CPM) in hepatoblastoma (HB). Patients with a refractory or relapsing HB after first-line therapy as per SIOPEL 2 and 3 protocols were eligible. All patients were to receive two courses of CPM 2 g/m(2) on days 1 and 2 at 3-week intervals. Eighteen patients were included; 17 were evaluable for response. Prior treatment was cisplatinum alone (1 patient) or cisplatinum-carboplatin-doxorubicin (17 patients). The disease status at the beginning of CPM was: progressive during first-line treatment (10 patients), persistent unresectable disease at the end of the protocol (2 patients), relapse (6 patients). Tumour response was partial response (1 patient), stable disease (1 patient), progressive disease (15 patients) and not evaluable in one. All patients died, 17 of progressive disease and one of surgery complications. The low response rate (1/17) led the SIOPEL group to conclude that single-agent CPM is not effective for the treatment of relapsing or refractory HB.  相似文献   
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