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21 patients, whose age ranged from 17 to 60 years and who had not been previously treated with antibiotics or other drugs, received bacampicillin as a perioperative prophylaxis for minor operations in the oral cavity. Four oral doses of bacampicillin were administered: each dose of 800 mg every 12 h, and the last dose was administered 2 h before surgery. To assess bacampicillin serum concentrations two blood samples were collected from each patient: the first sample was obtained 1 h before surgery and the second one during surgery. Together with the second blood sample, small quantities of gingiva and bone were obtained from each patient to also assess the antibiotic concentrations in these tissues (microbiological method). The results show that bacampicillin reaches high concentrations in both the blood and tissues studied by us, and that a direct correspondence exists between blood and gingival and bone tissue concentrations. Furthermore, it should be noted that no postoperative infections developed in our patients. These results lead to the conclusion that bacampicillin appears to be a suitable drug in the therapy of dental infections. 相似文献
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Duncan WC; Illingworth PJ; Young FM; Fraser HM 《Human reproduction (Oxford, England)》1998,13(9):2532-2540
The molecular mechanisms involved in luteolysis are still unclear in the
primate. This study aimed to investigate the effect of induced luteolysis
on the ovarian luteinizing hormone (LH) receptor and the steroidogenic
enzyme, 3beta-hydroxysteroid dehydrogenase (3beta-HSD) in the marmoset
monkey. Luteolysis was induced in the mid-luteal phase either directly by
systemic prostaglandin F2alpha (PGF2alpha), or indirectly by LH withdrawal
using systemic gonadotrophin releasing hormone antagonist (GnRHant)
treatment. The LH receptor was studied by isotopic mRNA in-situ
hybridization and in-situ ligand binding and 3beta-HSD expression was
studied using isotopic mRNA in-situ hybridization and immunohistochemistry.
Induced luteolysis was associated with a reduction in the expression of LH
receptor (P < 0.0001) and 3beta-HSD mRNA, closely followed by a
reduction in the LH receptor (P < 0.05) and 3beta-HSD protein
concentrations within 24 h. There were no differences in the findings
whether luteolysis was induced with PGF2alpha or GnRHant. This study shows
that disparate mechanisms to induce luteolysis in the primate result in an
identical rapid loss of the LH receptor and 3beta-HSD. In conclusion,
induced luteolysis leads to rapid loss of the steroidogenic pathway in
luteal cells.
相似文献
16.
A case of somatostatin-producing pancreatic tumor associated with severe insulindependent diabetes mellitus and ketoacidotic
coma is reported. The tumor, a 10-cm expansile mass arising from the pancreatic tail of a 70-yr-old woman, was first detected
by ultrasonography, performed because of abdominal pain, and subsequently confirmed by computed tomography and fine-needle
tumor aspiration. Pathologic investigation showed a predominatly solid-trabecular structure with scattered microacini and
psammomatous bodies. A large proportion of tumor cells expressed somatostatin and/or calcitonin. Following resection of the
primary tumor and three peripancreatic lymph nodes with metastases, the patient recovered rapidly from her diabetic syndrome
and remained in substantially good health during a subsequent 8-yr follow-up period, without evidence of tumor recurrence. 相似文献
17.
Hepatocyte growth factor (HGF), a stimulator of angiogenesis and cell migration, regulates the growth of a wide variety of
cells by binding to its high-affinity receptor met and is involved in the growth and aggressiveness of several tumors. In
this study we investigated the expression of HGF and met in normal endocrine cells and related neoplasms of the gut and pancreas
to verify their possible role in tumor pathogenesis, growth, and aggressiveness. Normal tissues and 60 different endocrine
tumors were immunostained using specific antibodies directed against HGF, met, and various hormones. HGF immunoreactivity
(IR) was found in antroduodenal G cells, rectal enterochromaffin (EC) cells, and pancreatic A and B cells, whereas met IR
was detected in antral EC and G cells, and in pancreatic B cells; 46 of 60 tumors examined were positive for HGF, and they
were mainly represented by ECL-, EC-, and L-cell neoplasms. met IR was identified in 50/60 tumors of various phenotypes. HGF
and met coexpression was found in 42/60 cases, most of which were represented by EC-cell tumors. HGF/met coexpression was
significantly more frequent in ileolonic EC-cell tumors, which in the majority of cases were malignant, than in appendiceal
EC-cell tumors, which were all benign. Our results demonstrated, for the first time, that HGF and met are specifically distributed
in normal gut and pancreatic endocrine cells and, in addition, suggest that HGF and met may be implicated as autocrine/paracrine
factors regulating the growth of gastroenteropancreatic endocrine tumors, mainly of ileocolonic EC-cell carcinoids. 相似文献
18.
Fausto Sessa Daniela Furlan Anna Genasetti Paola Billo Maddalena Feltri Carlo Capella 《Diagnostic molecular pathology》2003,12(2):96-102
We studied the MSI (microsatellite instability) status and p53 expression in a series of 71 gallbladder cancers (GCs) of different histologic type. All neoplasms were examined combining a microsatellite analysis at mononucleotide locus BAT-26 and an immunohistochemical study for hMSH2, hMLH1, and p53 proteins and markers of gastric and intestinal differentiation. All the 71 GCs were MSS (microsatellite stable). The p53 protein was found in 100% of undifferentiated GCs, 67% of conventional gallbladder adenocarcinomas, 50% of mucinous adenocarcinomas, and 20% GCs with squamous differentiation. All 71 MSS tumors showed presence of immunohistochemical expression of both hMLH1 and hMSH2 gene products. We concluded that microsatellite instability does not play a role in the developing of GC while p53 seems to be the most important alteration found in a large proportion of these cancers, with the only exception of mucinous and squamous gallbladder carcinomas. 相似文献
19.
We studied the expression of p53 in 80 gallbladder carcinomas, 43 peritumoral mucosae, 5 adenomas and 20 mucosae of non tumoral gallbladders. Gallbladder cancers were classified according to WHO criteria. We found p53 overexpression in 51 out of the 80 gallbladder cancers (64%). p53 expression was variable in different histologic subtypes: 100% of intestinal type, 66% of papillary type, 83% of adenosquamous carcinomas and 66% of giant cells cancers showed immunoreactive cells. In well and moderately differentiated conventional gallbladder adenocarcinomas we found 60% of positive cases, while, among poorly differentiated conventional cancers, 83% were immunoreactive. All mucinous adenocarcinomas were p53-negative. In peritumoral dysplastic mucosae, p53 was expressed in 23 out 38 cases (60%), 22 (96%) of which were associated to a p53-positive adenocarcinoma. On the contrary, only 5 of the 15 p53-negative dysplastic lesions (33%) were associated to an p53-immunoreactive adenocarcinoma. Metaplastic lesions, of gastric and intestinal type, and adenomas were completely p53-negative. In conclusion, our data suggest that p53 expression is an early event, frequently involved in gallbladder carcinogenesis, and related to different histologic subtypes of gallbladder adenocarcinomas. 相似文献
20.
Carlo Capella Cristina Riva Guido Rindi Fausto Sessa Luciana Usellini Annamaria Chiaravalli Luciano Carnevali Enrico Solcia 《Endocrine pathology》1991,2(2):92-110
Forty-two duodenal and 3 upper jejunum tumors from 44 patients were investigated. All tumors were tested immunohistochemically for gastroenteropancreatic hormones and general endocrine cell markers. Twenty-eight of the 45 tumors (62%) proved to be gastrin cell tumors, with (12 cases) or without (16 cases) associated Zollinger-Ellison syndrome. Zollinger-Ellison syndrome was part of type 1 multiple endocrine neoplasia syndrome in 3 cases. Twenty-three of the 28 gastrin cell tumors (82%) were from proximal duodenum, 2 were from the second part of the duodenum, and 3 were from the upper jejunum. Seven cases were somatostatin cell tumors, 6 of which were from the ampullary region; 5 cases were associated with biliary tract disease and 2 with associated cutaneous neurofibromatosis. Four ganglioneuromatous paragangliomas, from the ampullary region or nearby duodenum, showed somatostatin cells, coupled with pancreatic polypeptide cells in 2 cases. Two serotonin-producing argentaffin carcinoids were also identified. In addition to the main cell type, 30 tumors showed one or more, usually minor, cell populations producing somatostatin, serotonin, cholecystokinin, pancreatic polypeptide, insulin, neurotensin, or the alpha chain of human chorionic gonadotropin. Only 3 tumors lacked hormone immunoreactivity. Some correlation has been noted between histological structure and hormone content of tumor cells, with prevalence of broad gyriform trabeculae and vascular pseudorosettes among gastrin cell tumors, tubuloacinar patterns among somatostatin cell tumors, thin parallel trabeculae among PP cell growths, and a solid nest pattern among argentaffin carcinoids. Deep infiltration of the intestinal wall was observed in 22 tumors, 6 of which also had metastases to local lymph nodes. All metastatic cases were among ZES tumors or ampullary somatostatin cell tumors. Ganglioneuromatous paragangliomas and nonfunctioning gastrin cell tumors had essentially benign behavior, even when involving deep strata of the intestinal wall. Post operative follow-up study of 36 cases, including all metastatic tumors, showed no evidence of tumor-related death or progressive tumor disease. 相似文献