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1.
Two cases of internal herniation through a defect in the broad ligament of the uterus are described. Both were successfully treated laparoscopically. This rare condition should be borne in mind when a middle-aged woman presents with colicky lower abdominal pain. The cause is unknown, but both congenital and acquired origins have been proposed. As far as emergency situations are concerned, laparoscopy has proven to be both a diagnostic and a therapeutic tool.  相似文献   
2.
BACKGROUND: Retroperitoneal leiomyosarcomas (RLMS) are a challenging clinical entity. The vast majority of patients are operated on when tumors are advanced. We report herein a case of RLMS, mimicking acute appendiceal disease and treated successfully via laparoscopy. METHODS: A 37-year-old woman, para 1, was admitted to our department for right lower quadrant abdominal pain, fever, and leukocytosis. She had no changes in gastrointestinal and urologic function. A physical examination revealed the presence of abdominal guarding, rebound, and a tender mass in the right lower quadrant. The abdominal ultrasound showed an inhomogeneous ovoid mass (6 cm in diameter) located below the cecum, with no definite margins, and consistent with an appendiceal abscess. The patient was referred for laparoscopy. The procedure was performed with the aid of 3 ports: a 12-mm trocar in the umbilicus (open technique), a 10-mm trocar in the left iliac fossa, and a 5-mm one in the supra-pubic space. On inspection of the abdominal cavity, a retroperitoneal 6-cm mass was immediately found below the cecum and the appendix. Neither intraperitoneal seeding nor suspected lymph nodes were present. After dissection of the parietal peritoneum, the mass appeared to be encapsulated and well demarcated from all surrounding structures. It was eventually dissected and removed via a plastic bag. A standard appendectomy was also performed. The postoperative course was uneventful, and the patient was discharged on the 3rd day. The histology analysis of the resected specimen showed a totally excised G2 leiomyosarcoma. The appendix had no signs of inflammation. Postoperatively, the patient underwent a total-body CT-scan, which had no signs of residual or distant disease. No adjuvant therapy was necessary. At an 18-month follow-up, the patient was doing well and was disease free. CONCLUSION: Surgery represents the main therapeutic option for resectable RLMS. Laparoscopy is a useful diagnostic tool that allows safe resection of incidentally discovered, small and well encapsulated RLMS.  相似文献   
3.
Local control of Leydig cell arginine vasopressin receptor by naloxone   总被引:2,自引:0,他引:2  
Arginine vasopressin (AVP) and beta-endorphin are present within the testis where they could act as paracrine effectors of steroidogenesis. In this study we investigated the effect of naloxone, an opioid receptor antagonist on Leydig cell AVP receptor. Intratesticular injection of increasing doses of naloxone (0.1-100 micrograms) resulted 24 h later in a dose-dependent increase in Leydig cell AVP binding capacity. This effect occurred locally since s.c. injection of similar doses of naloxone did not alter the testicular AVP receptor content and intratesticular injection enhanced AVP receptor density only in the naloxone-treated testis but not in the contralateral vehicle-treated testis. Scatchard plot analysis of the data revealed that naloxone locally injected altered AVP binding capacity without change in affinity. These results suggest that in addition to their known paracrine effects in the testis, endogenous opioid peptides may locally control the testicular AVP system by modulating AVP receptor capacity.  相似文献   
4.
We report the first case of microfilaria infection in a free‐flying owl Athene noctua in Italy. A macroparasite, about 10.1‐mm long, was observed in the right chamber of the heart. On microscopic examination microfilariae were seen in liver, kidney, myocardium and lungs, although no cellular reaction was present in association with the parasites in any of these tissues. Because of the low pathogenicity of this parasite, infection with microfilaria may be not harmful in wild owls.  相似文献   
5.
These data collect the advance made in the last few years in our laboratory in defining one epitope from the thyroglobulin (Tg) molecule (660 KDa) inducing Experimental Autoimmune thyroiditis (EAT) in CBA/J mice. We achieved the characterization of one EAT-inducer Tg peptide by combining "in vitro" biochemical and immunological approaches and "in vivo" studies. Since T cells recognize degraded forms of the antigen and since endogenous antigens preferentially activate class I-restricted T cells, we hypothesized that one cytotoxic T cell hybridoma, named HTC2, which prevents further EAT induction in mice injected with Tg would be specific for one EAT inducer peptide. In order to identify one Tg epitope inducing EAT, enzymatic treatment of the protein by trypsin, HPLC purification and sequence analysis were performed. Simultaneously, tryptic digests were used to pulse CBA/J macrophages and tested for their ability to be recognized by HTC2 cells. Lastly, when digests were recognized by HTC2 cells their capacity to induce EAT in CBA/J mice was evaluated. To further assess the pathogenicity of the sequenced Tg peptide, one synthetic peptide was made and its capacity to induce EAT verified. By this procedure we identified for the first time one 40 amino-acid peptide from human thyroglobulin inducing EAT in CBA/J mice.  相似文献   
6.
BACKGROUND AND AIM: The wide diffusion and increasing use of laparoscopic surgery prompts the authors to broaden discussion to its validity and diagnostic-therapeutic use in emergency abdominal surgery. The aim was to evaluate the efficacy of laparoscopic surgery in the light of reports in the international literature and in relation to the situation in our hospital. METHODS: From April 1994 to May 1998, out of 1016 emergency abdominal operations performed at our hospital, 783 (77.5%) used a laparoscopic approach for diagnostic and therapeutic purposes: intestinal occlusion: 26 cases; gastrointestinal ulcer pathology: 15 cases; hepatobiliary pathology: 398 cases; "pelvic" pathology: 305 cases; colic pathology: 39 cases. These represent 24.4% of all laparoscopic procedures carried out during the same period. We preferred to use immediate laparotomic access in patients with the following characteristics: anamnesis of previous surgery for malignant pathologies; anamnesis of more than two major abdominal operations; massive intestinal distension; patients whose general conditions were a contraindication to a laparoscopic approach. RESULTS: The conversion rate was 6.2% (49 cases) with morbidity of 3.4% (25 cases) and a mortality rate of 0.2% (2 cases). A final diagnosis was made in 763 patients (97.4%) with the possibility of treating 719 of them (94.2%), again using a laparoscopic approach. CONCLUSIONS: It is right to regard the laparoscopic approach in emergency abdominal surgery as a feasible and safe model, offering a high potential for diagnosis and therapy if appropriately performed by an expert and well coordinated team. The increased experience of mini-invasive surgery and the improved range of instruments available make the laparoscopic approach a valid alternative to laparotomy, even in the event of emergency abdominal pathologies.  相似文献   
7.
From 1989 to 1998 we treated 94 patients with pancreatic pseudocysts. 55 patients underwent laparotomy (external drainage of the cyst, sequestrectomy). 14.5% patients of this group presented with postoperative complications, mean hospital stay was 36 days. During 1997-1998 we performed US-controlled punctures and drainage in 37 patients with pancreatic pseudocysts. This method was efficient in 83.7% of the cases without sequesters in the cystic cavity. Use of this method allowed to decrease the percentage of complications and lethality rate, and reduce the mean hospital stay by 47.2%.  相似文献   
8.
Inhibition of rat liver fibrogenesis through noradrenergic antagonism   总被引:25,自引:0,他引:25  
The effect of adrenergic innervation and/or circulating catecholamines on the function of liver fibrogenic cells is poorly understood. Our aim was to investigate the effects of noradrenergic antagonism on carbon tetrachloride (CCl4)-induced liver fibrosis in rats. Two weeks of CCl4 induced an approximately 5-fold increase in the area of fibrosis as compared with controls. The addition of 6-hydroxydopamine (OHDA), a toxin that destroys noradrenergic fibers, decreased fibrosis by 60%. After 6 weeks of CCl4, the area of fibrosis increased about 30-fold in CCl4-treated animals and was decreased by 36% with OHDA. At 2 weeks, OHDA abrogated the CCl4-induced increase in mRNA level of tissue inhibitor of matrix metalloproteinases-1 (TIMP-1), an inhibitor of extracellular matrix degradation, and it greatly reduced it at 6 weeks. Finally, when rats treated with CCl4 for 2 weeks also received prazosin, an antagonist of alpha1-adrenergic receptors, fibrosis was decreased by 83%. In conclusion, destruction of noradrenergic fibers or antagonism of noradrenergic signaling through alpha1 receptors inhibited the development of liver fibrosis. Because adrenoreceptor antagonists have a very sound safety profile, they appear as attractive drugs to reduce liver fibrogenesis.  相似文献   
9.
Safety is considered an important aspect of life and well‐being. However, few studies have examined the relationship between safety and well‐being among children, especially in Latin American. This study aims at analyzing the relationship between perceptions of safety and children's subjective well‐being, considering children's school, city context, and sex. Participants were 2,200 Brazilian children (10–13 years old) who answered the single item on Overall Life Satisfaction, the Satisfaction With Life Student Scale, and four items regarding safety perceptions. Through analysis of variance and structural equation modeling (SEM), results indicate that children who live in inner cities and study in private schools have significantly higher averages of safety perception. Also, boys present higher averages about how safe they feel. SEM presents a positive and significant relationship between safety perception and children's subjective well‐being and multigroup SEM indicates invariance of the model across groups. Safety is presented as an important component of well‐being. Interventions aimed at promoting safety and community ties can enhance children's well‐being.  相似文献   
10.

Background

A limited number of studies aimed at investigating the possible association of Y‐chromosome haplogroups with microdeletions of the azoospermia factors (AZFs) or with particular infertile phenotypes, but definitive conclusions have not been attained. The main confounding elements in these association studies are the small sample sizes and the lack of homogeneity in the geographical origin of studied populations, affecting, respectively, the statistical power and the haplogroup distribution.

Materials and methods

To assess whether some Y‐chromosome haplogroups are predisposing to, or protecting against, azoospermia factor c (AZFc; b2/b4) deletions, 31 north Italian patients carrying the AZFc b2/b4 microdeletion were characterised for 8 Y‐chromosome haplogroups, and compared with the haplogroup frequency shown by a north Italian population without the microdeletion (n = 93).

Results and discussion

A significant difference was observed between the two populations, patients with microdeletions showing a higher frequency of the E haplogroup (29.3% vs 9.7%, p<0.01). The geographical homogeneity of the microdeleted samples and of the control population, controlled at microgeographical level, allows the possibility that the geographical structure of the Y genetic variability has affected our results to be excluded.

Conclusion

Thus, it is concluded that in the north Italian population Y‐chromosome background affects the occurrence of AZFc b2/b4 deletions.Y‐chromosome long‐arm microdeletions are found in 5–10% of men with severe oligospermia and non‐obstructive azoospermia, and encompass one or more azoospermia factor (AZF) loci. Deletions of the azoospermia factor c (AZFc) region are clearly among the most commonly known molecular causes of spermatogenic failure in men.1 These deletions are caused by homologous recombination between the 229‐kb‐long b2 and b4 amplicons2 and span 3.5 Mb. Eight different gene families are removed by AZFc deletions, including all members of the DAZ gene family, which represents the stronger candidate for the AZFc phenotype.1,2,3,4,5,6,7 Although all AZFc deletions are essentially identical in molecular extension, people carrying these microdeletions present variable infertile phenotypes, suggesting the involvement of environmental factors and/or other genetic regions. Furthermore, the function of the AZF genes in human spermatogenesis and the role of the Y‐chromosome background in the predisposition to occurrence of deletions is still largely unknown.At present, around 250 Y single‐nucleotide polymorphisms have been discovered and their phylogenetic relationships are well known.8 These polymorphic markers of the male‐specific region of the Y chromosome define monophyletic groups of the Y chromosome, which hereafter we will name as “haplogroups”.A limited number of studies have investigated the possible association of Y‐chromosome haplogroups with microdeletions or with a particular infertile phenotype,9 but the contribution of predisposing factors or genetic background to causing deletions is still debated. In particular, only three studies have investigated the possible association between Y‐chromosome haplogroups and AZF deletions,10,11,12 all of them failing to establish important associations. These works studied such associations in an European population involving 73 microdeleted samples of heterogeneous geographical origin,10 in a northwestern European population involving 50 patients11 and in a Japanese population, more geographically localised but represented by a very low number of people with microdeletions (six patients).12 All the previous studies that found some suggestion of an association with Y‐chromosome haplogroups dealt with infertility. They reported a considerable over‐representation of the haplogroup K(xL,N,O1,O3c,P) in Danish men with reduced sperm count, which did not reach significance probably because of a small sample size,13 and D2b Y lineage in Japanese men with reduced sperm count,14 not confirmed by a later study.12However, these association studies require particular attention to two principal factors: (1) the geographical structure of the Y‐chromosome variations in the population under investigation, because the Y‐chromosome genetic variability is highly geographically structured and the Y‐haplogroup distribution changes over different geographical areas15; and (2) the number and selection criteria of the patient and control groups.To assess whether some Y‐chromosome haplogroups predispose to, or protect against, AZFc deletion, we have defined and compared Y‐chromosome haplogroup distribution in a group of unrelated Italian infertile men harbouring the b2/b4 deletion (n = 41, 31 of whom were from north Italy) and in a control group represented by fertile men without microdeletions (fathers of at least one child) from north Italy (n = 93).  相似文献   
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