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161.
Comparison of the performance of the Gea extracorporeal knot with the Roeder extracorporeal knot and the classical knot 总被引:2,自引:0,他引:2
Moreno M Magos FJ Arcovedo R Olachea P Palacios JA Salazar A Ramírez ME Herrera JJ 《Surgical endoscopy》2004,18(1):157-160
Background: Laparoscopy is useful to treat surgical diseases, yet tying sutures in the cavity is a challenge. A knot to secure tissue approximation, which would be hand-made, secure, simple, easy, quick, reliable, and extracorporeal without extra mechanical devices, was developed and named the Gea knot. Methods: A comparative study of the Gea knot, the Roeder knot, and the classical surgical knot, as the gold standard, using polypropylene, silk, catgut, polyglycolic acid, and Polyglactin 910, all of them of 1-0 caliber, was performed in pigs. Measurements were time to perform, slippage, and breaking point which was measured with a manual digital tensiometer. Results: The Gea knot was significantly faster statistically to perform than the Roeder knot and more resistant against rupture and slippage. The slippage rate was significantly lower statistically in the Gea knot than in the Roeder knot when Polyglactin 910 and polypropylene were used. Conclusion: The Gea knot is a good alternative for laparoscopic procedures. 相似文献
162.
Ramírez JM Ramírez AI Salazar JJ Rojas B De Hoz R Triviño A 《Cells, tissues, organs》2004,178(3):180-185
We studied Schlemm's canal (SC) and other posttrabecular structures of aqueous humor outflow in eyes from human fetuses (at 24, 26, 33 and 36 weeks of gestation), eyes from normal children (2 months and 8 years old) and normal adult eyes, using mesoscopy/diaphanization and light microscopy. This study points to the presence of a collector canal parallel to the outer wall of SC (the outer collector). At 24 weeks of gestation, the SC was observable throughout the entire circumference (360 degrees) and the anlage of the outer collector was present. At 26 weeks of gestation, the outer collector was still growing. At 33 weeks of gestation, the outer collector was parallel to the SC and had become visible in some sectors. At 36 weeks, the SC and the outer collector were clearly defined and connected by intercanal links. The intrascleral plexus was growing. At 2 months, the deep intrascleral plexus and the episcleral plexus continued to grow, developing by sectors. At 8 years of age, the same structures corresponded to those in adults. The outer collector and the intrascleral plexuses were divided into sectors not greater than 120 degrees. 相似文献
163.
164.
Santin M Alcaide F Benitez MA Salazar A Ardanuy C Podzamczer D Rufi G Dorca J Martin R Gudiol F 《Epidemiology and infection》2004,132(3):425-432
A retrospective population-based study was conducted between January 1990 and December 1998 to investigate the incidence of Mycobacterium kansasji disease and the heterogeneity of the isolates in a well-defined geographical area in Catalonia, Spain. A total of 136 patients were identified. Overall incidence and incidence in AIDS patients was 1.5 (95% CI 1.2-1.8) and 1089.6 (95% CI 689-1330) cases/100,000 persons per year respectively, which is comparable to that reported from most of other geographical areas. Surprisingly, although 7 subtypes of M. kansasii have been consistently reported, in the present study 91 of the 93 isolates (97.8%) tested for genotype were subtype I, regardless of HIV status of the patients. In conclusion, the high rate of infection observed in the AIDS population contributes significantly to the burden of the M. kansasii disease in our area. M. kansasii disease in our geographical area was almost exclusively caused by subtype I regardless of HIV status. 相似文献
165.
Le Brazidec JY Kamal A Busch D Thao L Zhang L Timony G Grecko R Trent K Lough R Salazar T Khan S Burrows F Boehm MF 《Journal of medicinal chemistry》2004,47(15):3865-3873
The heat shock protein Hsp90 has increasingly become an important therapeutic target especially for treatment of cancers. Inhibition of the ATPase activity of Hsp90 by natural products (e.g., 17-allylaminogeldanamycin or radicicol) leads to the ubiquitination of oncogenic client proteins such as Her-2, Raf-1, and p-Akt followed by their proteasomal degradation. Hsp90 inhibitors simultaneously target multiple oncogenic proteins and provide an advantage for cancer therapy due to the potential for increased efficacy and overcoming drug resistance. In an effort to convert geldanamycin into a druglike compound with better pharmacokinetic properties and efficacy in human tumor xenograft models, geldanamycin was derivatized on the 17-position to prepare new analogues such as 17-geldanamycin amides, carbamates, and ureas and 17-arylgeldanamycins. All the compounds were first evaluated ex vivo using a cell-based Her-2 degradation assay and in vitro using biochemical assays that measure recombinant Hsp90 (rHsp90) competitive binding and changes in rHsp90 conformation. In addition, we confirmed the selectivity of geldanamycin analogues for Hsp90 derived from tumor cells using a novel cell lysate binding assay. 相似文献
166.
OBJECTIVE: To investigate multiple levels of influence with respect to the lack of recent condom use among a high risk sample of adolescent males recruited from short term detention facilities. METHODS: A cross sectional survey of 231 adolescent males serving, predominantly, short term detention sentences. Assessments were conducted using audiocomputer assisted self interviewing. Condom use during the most recent sexual event was assessed as well as 20 potential correlates of not using condoms. Correlates were assessed within five levels of causation: personal, relational, peer affiliation, family, and societal. RESULTS: Nine correlates achieved bivariate significance (p<0.05). Of these, the personal level correlates were particularly important in a multivariate model. The motivation subscale from the Condom Barriers Scale was the strongest multivariate correlate of recent condom use. Adolescents scoring below the median were about 3.4 times more likely to report lack of recent condom use (p=0.0006). Adolescents indicating they had ever caused a pregnancy were about 2.5 times more likely to report lack of condom use (p=0.02). Finally, those reporting their peers did not use condoms were about twice as likely to report lack of use (p=0.048). CONCLUSION: Upon investigating multiple levels of potential influence on condom use, the multivariate findings suggest that personal level factors may be the most important determinant of non-use among adolescent males in short term detention facilities. Although structural changes may be needed to influence some forms of safer sex behaviour, direct intervention with adolescent males may be justified to favourably alter determinants of condom use. 相似文献
167.
Each year an estimated 500,000 to 600,000 women die due to complications from childbirth, making this one of the leading causes of death globally for women in their reproductive years. In 1987 a global initiative was launched to address the problem, but few developing countries since then have experienced a documented significant decline in maternal mortality levels. Honduras represents an exception. Between 1990 and 1997 the country's maternal mortality ratio--the number of deaths due to complications during pregnancy, childbirth and the postpartum period per 100,000 live births--declined 40% from 182 to 108, one of the largest reductions ever documented in such a short time span in the developing world. This paper draws on three political science literatures--constructivist international relations theory, policy transfer and agenda-setting--to explain how political priority for safe motherhood emerged in Honduras, a factor that underpinned the decline. Central to the explanation is the unusually cooperative relationship that developed between international donors and national health officials, resulting in effective transfer of policy and institutionalization of the cause within the domestic political system. The paper draws out implications of the case for understanding the political dynamics of health priority generation in developing countries. 相似文献
168.
169.
Structural requirements of the N-terminal region of GLP-1-[7-37]-NH2 for receptor interaction and cAMP production 总被引:2,自引:0,他引:2
Sarrauste de Menthière C Chavanieu A Grassy G Dalle S Salazar G Kervran A Pfeiffer B Renard P Delagrange P Manechez D Bakes D Ktorza A Calas B 《European journal of medicinal chemistry》2004,39(6):473-480
A series of GLP-1-[7-36]-NH(2) (tGLP-1) and GLP-1-[7-37] analogs modified in position 7, 8, 9 and 36, have been designed and evaluated on murine GLP-1 receptors expressed in RIN T3 cells for both their affinity and activity. Ten of the synthesized peptides were found full agonists with activities superior or at least equal to that of the native hormone. Five of them were investigated for their plasmatic stability and the most stable, [a(8)-desR(36)]GLP-1-[7-37]- NH(2) (Compound 8), evaluated in vivo in a glucose tolerance test which confirmed a clearly longer activity than that of the native hormone. We also performed circular dichroism study and propose a hypothetical structural model explaining the most part of observed activities of GLP-1 analogs on RIN T3 cells. 相似文献
170.