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61.
In clinical settings, Lactobacillus johnsonii La1 administration has been reported to have a favorable effect on Helicobacter pylori-associated gastritis, although the mechanism remains unclear. We administered, continuously through the water supply, live La1 to H. pylori-infected C57BL/6 mice and followed colonization, the development of H. pylori-associated gastritis in the lamina propria, and the levels of proinflammatory chemokines macrophage inflammatory protein 2 (MIP-2) and keratinocyte-derived cytokine (KC) in the serum and gastric tissue over a period of 3 months. We documented a significant attenuation in both lymphocytic (P=0.038) and neutrophilic (P=0.003) inflammatory infiltration in the lamina propria as well as in the circulating levels of anti-H. pylori immunoglobulin G antibodies (P=0.003), although we did not observe a suppressive effect of La1 on H. pylori colonizing numbers. Other lactobacilli, such as L. amylovorus DCE 471 and L. acidophilus IBB 801, did not attenuate H. pylori-associated gastritis to the same extent. MIP-2 serum levels were distinctly reduced during the early stages of H. pylori infection in the La1-treated animals, as were gastric mucosal levels of MIP-2 and KC. Finally, we also observed a significant reduction (P=0.046) in H. pylori-induced interleukin-8 secretion by human adenocarcinoma AGS cells in vitro in the presence of neutralized (pH 6.8) La1 spent culture supernatants, without concomitant loss of H. pylori viability. These observations suggest that during the early infection stages, administration of La1 can attenuate H. pylori-induced gastritis in vivo, possibly by reducing proinflammatory chemotactic signals responsible for the recruitment of lymphocytes and neutrophils in the lamina propria.  相似文献   
62.
The objectives of this study were to measure the concentrations of PAHs (polycyclic aromatic hydrocarbons) in three particle fractions [particulate matter (PM) <1 μm in diameter (PM1), PM <2.5 μm in diameter (PM2.5) and the respirable fraction (<4 μm in diameter)] in the air of offices in which smoking was allowed and forbidden, respectively, and to identify the potential sources by applying the Positive Matrix Factorization (PMF) model. We sampled the indoor air of both environments during 24-h periods for PM1 and PM2.5 and conducted personal exposure measurements for the respirable PM fraction during working hours. The measurements indicated a clear difference in the levels of carcinogenic PAHs (PAHcancer) in the two office environments. In the smokers’ office, PAHcancer levels fell by >70% during the weekend relative to working days, implying the importance of smoking and dust resuspension sources. The PMF model identified four contributory factors–sources: smoking, dust resuspension and two different vehicle-related sources. For 15 PAHs, the same factor made the largest contribution to both the PM1 and PM2.5 fractions, implying a common origin and further supporting the validity of the proposed approach. For the majority of the carcinogenic PAHs, smoking and dust resuspension made the strongest contribution (>90%) to both the PM1 and PM2.5 fractions. Although our PMF analysis confirmed the well-known contribution of smoking and traffic-related sources to levels of PAHs, the identification of dust resuspension as a separate source of PAHs is of great interest and requires further study.  相似文献   
63.
Purpose: Our objective was to apply ooplasmic round spermatid nuclear injections for the treatment of nonobstructive azoospermia. Materials: Participants were nine azoospermic men who had previously undergone diagnostic testicular biopsy. Spermatogenetic arrest was diagnosed at the round spermatid stage (n=6) or primary spermatocyte stage (n=3). A second (therapeutic) testicular biopsy was performed and round spermatid nuclei were recovered from all the participants. Results: Forty-nine mature oocytes were successfully injected with nuclei and then cultured for 72 hr. Twenty-four embryos were transferred to nine women. No pregnancy was achieved. Conclusions: Round spermatids can be recovered from therapeutic testicular biopsy material of men negative for round spermatids in previous routine diagnostic testicular biopsy specimens. Round spermatid nuclear injections may play a role in the treatment of nonobstructive azoospermia.  相似文献   
64.
Laparoscopic versus open appendectomy: Which way to go?   总被引:19,自引:0,他引:19  
AIM: To compare the outcome of laparoscopic versus open appendectomy. METHODS: Prospectively collected data from 293 consecutive patients with acute appendicitis were studied. These comprised of 165 patients who underwent conventional appendectomy and 128 patients treated laparoscopically. The two groups were compared with respect to operative time, length of hospital stay, postoperative pain, complication rate and cost. RESULTS: There were no statistical differences regarding patient characteristics between the two groups. Conversion to laparotomy was necessary in 2 patients (1.5%). Laparoscopic appendectomy was associated with a shorter hospital stay (2.2 d vs 3.1 d, P = 0.04), and lower incidence of wound infection (5.3% vs 12.8%, P = 0.03). However, in patients with complicated disease, intra-abdominal abscess formation was more common after laparoscopic appendectomy (5.3% vs 2.1%, P = 0.002). The operative time and analgesia requirements were similar in the two groups. The cost of treatment was higher by 370 in the laparoscopic group. CONCLUSION: Laparoscopic appendectomy is as safe and efficient as open appendectomy, provided surgical experience and equipment are available.  相似文献   
65.
STUDY OBJECTIVE: To assess whether laparoscopy is a reliable technique for the investigation of women presenting with ascites and in whom the diagnosis remains obscure. DESIGN: Prospective nonrandomized clinical study (Canadian Task Force classification II-2). SETTING: University Departments of a tertiary referral center. PATIENTS: Women presenting in our institution with ascites in whom the diagnosis remained obscure after an extensive nonoperative diagnostic work-up. INTERVENTION: Undiagnosed cases were submitted to laparoscopy, and selective biopsy specimens were taken for histologic study. MEASUREMENTS AND MAIN RESULTS: Over a 3-year period, 73 patients were admitted to our institution with diffuse ascites. In 9 patients (12.3%), the diagnosis remained obscure, and these patients were further investigated with laparoscopy. Selective biopsy specimens obtained at laparoscopy clarified the specific cause of the ascites in all 9 patients. Peritoneal carcinomatosis was responsible in 5 patients (a metastatic gastrointestinal tumor in 1 patient, a malignant mesothelioma of the peritoneum in 1 patient, and a serous papillary carcinoma of the peritoneum and of the ovary in 2 and 1 patients, respectively). Three patients were found with miliary peritoneal tuberculosis, and the last patient had an unusual peritoneal reaction to methylene blue after laparoscopic adhesiolysis. CONCLUSION: Laparoscopy is a valuable means of assessing the peritoneal cavity in patients with unexplained ascites, where the primary cause remains unclear. The diagnosis can be accurately made with selective biopsy specimens, and appropriate treatment can be instituted without delay.  相似文献   
66.
Primary malignant melanoma of the oral mucosa.   总被引:3,自引:0,他引:3  
PURPOSE: The occurrence of primary oral melanoma is very rare. Large clinical series suggesting appropriate treatment modalities are lacking; the clinician has to rely on case reports to gain insight into the management of this tumor, which is much more aggressive than its skin counterpart.Patients and methods The cases of 5 patients with primary oral melanoma during a 6-year period were retrospectively reviewed. Four patients presented with tumors located in the maxilla. Preoperative workup included microscopic examination of incisional biopsy specimens for the confirmation of the diagnosis and thorough imaging of the body to rule out distant metastases. Histologically significant vertical invasion was found in all patients. No patient had distant metastases initially, and only 1 patient presented with neck disease. Primary treatment included wide local excision in 4 patients and therapeutic modified radical neck dissection in the 1 patient with neck node involvement on presentation. One patient was treated primarily with radiation therapy due to medically compromised status. Adjuvant immunochemotherapy (DAV protocol) was administered to 4 patients. Radiation therapy was used in an adjuvant fashion in 3 patients. RESULTS: All of the patients developed distant metastases to the lung and liver and eventually died of their disease. Survival ranged from 14 to 38 months (mean, 25.6 months). Local recurrence occurred in 1 patient and was attributed to positive surgical margins. Contralateral neck disease developed in the patient who underwent therapeutic neck dissection. CONCLUSIONS: The prognosis of primary oral melanoma remains poor despite adequate locoregional control of the disease. It seems that diagnosis is made late in the course of the disease when the primary tumor has already shed microscopic distant metastases.  相似文献   
67.

Background  

The aim of this study was to evaluate the risk factors of wound dehiscence and determine which of them can be reverted.  相似文献   
68.
69.

Introduction  

Modern treatment of posterior fossa ependymomas in children has improved the overall survival, but as more children live longer, the neuropsychological problems that they endure as result of the disease and its treatment become more the focus of attention.  相似文献   
70.
The immunodominant myelin basic protein (MBP) peptide comprising residues 87-99 is a self-antigen in multiple sclerosis (MS). In Lewis rats this epitope induces experimental allergic encephalomyelitis (EAE), a demyelinating disease of the central nervous system, and is a model of MS. Structure-activity studies have shown that Lys(91) and Pro(96) residues are important for encephalitogenicity. Replacement of Lys and/or Pro residues with Arg and/or Ala, respectively, results in suppression of EAE. A potent linear altered peptide ligand of the immunodominant sequence MBP(83-99) has been selected for clinical trial (Nat. Med. 2000, 6, 1167, 1176). In the present report, two cyclic analogues, cyclo(91-99)[Ala(96)]MBP(87-99) and cyclo(87-99)[Arg(91), Ala(96)]MBP(87-99) were designed by NMR and molecular modeling data on human MBP(87-99) epitope (Val(87)-His-Phe-Phe-Lys-Asn-Ile-Val-Thr-Pro-Arg-Thr-Pro(99)) and its linear antagonist peptide analogue [Arg(91), Ala(96)]MBP(87-99). These analogues (altered peptide ligands) inhibited EAE in Lewis rats and decreased inflammation in the spinal cord. In addition, the analogue cyclo(87-99)[Arg(91), Ala(96)]MBP(87-99) induced proliferation of human peripheral blood T-cells. These cyclic MBP(87-99) peptide analogues may lead to the design of potent antagonist mimetics for treating MS.  相似文献   
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