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排序方式: 共有1306条查询结果,搜索用时 31 毫秒
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Laureano Fernández-Cruz Rebeca Cosa Laia Blanco Sammy Levi Miguel-Angel López-Boado Salvador Navarro 《Journal of gastrointestinal surgery》2007,11(12):1607-1622
Laparoscopic pancreatic surgery (LPS) has seen significant development but much of the knowledge refers to small and benign
pancreatic tumors. This study aims to evaluate the feasibility, safety, and long-term outcome of the laparoscopic approach
in patients with benign, premalignant, and overt malignant lesions of the pancreas. This study, currently, is the largest
single center experience worldwide. One hundred twenty-three consecutive patients underwent laparoscopic pancreatic surgery
from April 1998 to April 2007, 20 patients with cysts or pseudocysts for acute and chronic pancreatitis, laparoscopic pancreatic
drainage was performed, and were excluded from the analysis. The 103 patients were divided based on preoperative diagnosis:
group I, inflammatory tumors for chronic pancreatitis (eight patients); group II, cystic pancreatic neoplasms (29 patients);
group III, intraductal papillary mucinous neoplasms (10 patients); group IV, neuroendocrine pancreatic tumors (NETs) (43 patients);
and group V ductal adenocarcinoma (13 patients). The median tumor size was 5.3 cm. Pathologic data include R
0 or R
1 resection (transection margins on the specimen were inked). Perioperative data, postoperative complications, and resection
modalities were compared using statistical analysis. Long-term outcomes were analysed by tumor recurrence and patient survival.
The overall conversion rate was 7%. Laparoscopic distal pancreatic resection was performed in 82 patients (79.6%). Laparoscopic
spleen-preserving distal pancreatectomy (Lap SPDP) was performed in 52 patients (63.7%), but with splenic vessels preservation
in 22% and without splenic vessels preservation in 41.5%. Laparoscopic en-bloc splenopancreatectomy (Lap SxDP) was performed
in 30 patients (36.6%) and laparoscopic enucleation (Lap En) in 20 patients (19.4%). There was no mortality. The overall complication
rate was 25.2, 16.7, and 40% after Lap SPDP, Lap SxDP, and Lap En, respectively. The overall morbidity rate was significantly
higher (p > 0.05) in the group of Lap SPDP without splenic vessels preservation comparing with Lap SPDP with splenic vessels preservation
because of the occurrence of splenic complications (20.6%). The overall pancreatic fistulas was 7.7, 10, and 35% after Lap
SPDP, Lap SxDP, and Lap En, respectively; the severity of fistula was significantly higher in the Lap En group (p > 0.05). The mean hospital stay was within 1 week in all groups, except in the group of ductal adenocarcinoma, which is 8 days.
In this series, 27 patients (26.2%) had malignant disease. R
0 resection was achieved in 90% of ductal adenocarcinoma and 100% for other malignant tumors. The median survival for ductal
adenocarcinoma patients was 14 months. This series demonstrates that LPS is feasible and safe in benign-appearing and malignant
lesions of the pancreas. 相似文献
4.
HIV-1 vertical transmission is thought to mainly take place by virus crossing the placental barrier. However, the mechanism by which HIV-1-infects placental cells remains to be elucidated. We have found that purified cytotrophoblasts as well as trophoblastic cell lines are susceptible to infection by different HIV-1 isolates as detected by DNA-PCR and release of infectious virus, although with very low efficiency. Purified trophoblast or trophoblastic cell lines express low levels of chemokine receptors CCR-5 and CXCR-4 but not CD4 on the cell surface. To test if those molecules were used as receptors for HIV-1 infection, placental cells were pretreated with antibodies to CD4, CC-chemokines, C-X-C chemokines. None of those treatments inhibited HIV-1 infection. In contrast, we have found that HIV-1 infection of placental cells was increased in cocultures of infected T-cell blasts and placental cells. More interestingly, antibodies to beta(2) integrins and to LFA-1 were able to significantly block infection of placental cells. Cell surface expression of ICAM-1, an adhesion molecule involved in attachment of leukocytes to placenta, was upregulated in HIV-1-infected placental cells. Placental cells were able to transfer HIV-1 infection to T-cell blasts. This transmission required cell to cell contact and was also inhibited by anti-LFA-1 antibodies. In summary our results suggest that placental trophoblast could be infected by HIV-1 by a mechanism involving T cell to placental contact. Moreover, placental infection enhanced ICAM-1 expression and leukocyte adherence, an event which was required to transfer HIV-1 infection to T cells. This provides an explanation of the virus passing through the placental barrier during in utero HIV-1 vertical transmission. 相似文献
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de Oliveira NM Vaca Sánchez R Rodriguez Fiesta S Lopez Salgado T Rodríguez R Bethencourt JC Blanes Zamora R 《Human reproduction (Oxford, England)》2004,19(2):262-265
BACKGROUND: There are few reports of pregnancy using immotile sperm, and none using a purely mechanical assessment of viability. METHODS: In this pilot study, we retrospectively analysed 66 cycles in 61 patients with determinant male factor, recording rates of fertilization, implantation, normal pregnancy and take-home babies achieved with ICSI. Sperm selection was based on morphologically normal appearance under the inverted microscope. Viability of immotile spermatozoa was assessed by the mechanical touch technique to observe tail flexibility and tail shape recovery. RESULTS: Of 17 ICSI cycles using frozen-thawed testicular sperm, six microinjected with immotile and 11 with motile sperm, we achieved fertilization rates of 65.7 and 74.3%, respectively, and five pregnancies (two and three, respectively). Of 49 ICSI cycles using fresh testicular sperm, 10 microinjected with immotile and 39 with motile sperm, we achieved fertilization rates of 73.4 and 64.4%, respectively, and 12 pregnancies (three and nine, respectively). CONCLUSIONS: Immotile (fresh and frozen-thawed) testicular sperm of normal morphological appearance can be used to achieve clinical pregnancy with ICSI. Our results strongly suggest that immotile sperm viability can be assessed by the mechanical touch technique. 相似文献
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Lucía Melguizo-Rodríguez Víctor J. Costela-Ruiz Enrique García-Recio Elvira De Luna-Bertos Concepcin Ruiz Rebeca Illescas-Montes 《Nutrients》2021,13(3)
The prevalence of hypovitaminosis D has risen in developed countries over the past few years in association with lifestyle changes and an increase in unhealthy habits. Vitamin D deficiency has been implicated in various diseases, including metabolic syndrome (MetS), which is clinically defined by a set of metabolic and vascular disorders. The objective of this study was to review scientific evidence on the relationship between MetS and vitamin D deficiency to support the development of prevention strategies and health education programs. An inverse relationship has been reported between plasma vitamin D concentrations and the features that define MetS, i.e., elevated serum concentrations of glucose, total cholesterol, low-density lipoproteins, triglycerides, glycosylated hemoglobin, and a high body mass index. Numerous studies have described the benefits of vitamin D supplementation to improve outcomes in individuals with MetS. Interventions to maintain optimal vitamin D concentrations are proposed as a preventive strategy against MetS. 相似文献
8.
Claudio Pinto María Raquel Ibez Gloria Loyola Luisa Len Yasmin Salvatore Carla Gonzlez Víctor Barraza Francisco Castaeda Rebeca Aldunate Loretto Contreras-Porcia Karen Fuenzalida Francisca C. Bronfman 《Nutrients》2021,13(6)
The biomedical potential of the edible red seaweed Agarophyton chilense (formerly Gracilaria chilensis) has not been explored. Red seaweeds are enriched in polyunsaturated fatty acids and eicosanoids, which are known natural ligands of the PPARγ nuclear receptor. PPARγ is the molecular target of thiazolidinediones (TZDs), drugs used as insulin sensitizers to treat type 2 diabetes mellitus. Medical use of TZDs is limited due to undesired side effects, a problem that has triggered the search for selective PPARγ modulators (SPPARMs) without the TZD side effects. We produced Agarophyton chilense oleoresin (Gracilex®), which induces PPARγ activation without inducing adipocyte differentiation, similar to SPPARMs. In a diet-induced obesity model of male mice, we showed that treatment with Gracilex® improves insulin sensitivity by normalizing altered glucose and insulin parameters. Gracilex® is enriched in palmitic acid, arachidonic acid, oleic acid, and lipophilic antioxidants such as tocopherols and β-carotene. Accordingly, Gracilex® possesses antioxidant activity in vitro and increased antioxidant capacity in vivo in Caenorhabditis elegans. These findings support the idea that Gracilex® represents a good source of natural PPARγ ligands and antioxidants with the potential to mitigate metabolic disorders. Thus, its nutraceutical value in humans warrants further investigation. 相似文献
9.
By means of injecting soot into the vessels of the uveal tract of the rabbit eye the character of changes in the architectonics of the vascular bed in dynamics of the burn process could be detected. It was found that a burn trauma produces changes in practically the whole uveal tract, but to a greater extent, in its anterior segment. Reduction of blood filling of the vessels or their total segmentary "switching-off" is connected with the development of reversible (thrombosis, oedema of endotheliocytes and surrounding stroma, hemolysis) and irreversible (destruction of the vascular wall, obliteration of vessels) structural changes. The degree of disturbances in blood circulation and reversibility of these changes depend on the severity of the burn. In case of less severe burns, total structural restoration of the vascular network in the nearest time is recorded, while in severe burns--partial restoration with elements of vascular net reconstruction of adaptive character. 相似文献
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