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Ten protein coding loci (6‐PGD, A1‐AT, ACP1, CaII, ESD, GC, GPX1, Hbβ, PGM1, and TF) were analyzed in the Mbenzele Pygmies from the Central African Republic. The frequency data were used to calculate the genetic distances between Mbenzele Pygmies and other African groups. In the principal coordinate plot of FST genetic distances, the Mbenzele cluster together with other Pygmies of the western cluster, the Biaka from C.A.R., Gielli from Cameroon, and Babinga from Congo. By contrast, they are considerably distanced from other Pygmy groups of the eastern cluster (Twa from Rwanda, Mbuti from Zaire). Genetic distances obtained using protein loci were compared with those based on microsatellite loci. The two distance matrices are insignificantly correlated (r = 0.268; one tail probability = 0.332), and the main difference is in the higher genetic affinity between the Mbenzele and Biaka Pygmies observed at the protein level. Although reasons underlying the discrepancy between inter‐populational variation at protein and DNA loci are not established with certainty, the comparison suggests that the genetic distance between the Mbenzele and Biaka Pygmies at microsatellite loci could have been shaped by genetic drift. Am. J. Hum. Biol. 14:9–14, 2002.© 2002 Wiley‐Liss, Inc.  相似文献   
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The results of the first 3 year' collaboration of the Italian Registry of Paediatric Chronic Peritoneal Dialysis (CPD) (1986–1988) are presented. This Registry acquired data on the majority of the paediatric patients treated with CPD in Italy, thus providing a national picture in a field where few nationwide surveys are available. Patients of less than 15 years of age at the start of dialysis were enrolled and clinical data collected until the age of 19 years. The number of nephrological paediatric centres participating in the Registry increased from 7 in 1986 to 11 in 1988. The total number of patients on CPD was 70 and the percentage of dialysed children treated with CPD ranged from 40.2% to 43.6%. Data on 89 peritoneal catheters were collected: during 1417 dialysis-months 70 catheter-related complications were observed (1:20.8 dialysis-months); actuarial catheter survival was 92.7% at 6 months, 84.8% at 1 year and 68.8% at 2 years. The incidence of peritonitis changed from 1 episode every 10.9 patient-months in 1986 to 1 every 19.8 in 1988. Abdominal hernias were the other main clinical complication observed. The survival of patients was 92.5% at 3 years, while the technique survival at the same time was 84%.  相似文献   
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BACKGROUND: We aimed to determine whether serum concentrations of anti-Müllerian hormone (AMH) can be used as a tool for prediction of the efficacy of sperm retrieval. METHODS: This was a prospective cohort observational study. AMH levels were determined in 47 men presenting for infertility evaluation. Group 1 consisted of 24 infertile patients diagnosed with non-obstructive azoospermia. Group 1 was further divided into two subgroups. The patients with spermatozoa in their testicular samples constituted group 1a (n = 13), while the patients with absence of spermatozoa constituted group 1b (n = 11). Twenty-three normozoospermic fertile men constituted group 2. Serum AMH was measured before obtaining testicular specimens. RESULTS: Testicular spermatozoa were recovered in 13 out of the 24 patients (54%). Demographic characteristics of the three groups were similar. The difference between serum AMH levels among the three groups did not reach statistical significance. CONCLUSIONS: We speculated that although AMH is secreted predominantly into the seminiferous tubules, studying serum samples might be more advantageous than seminal plasma because the presence of seminal proteases could influence AMH levels in the latter. However, our results did not demonstrate differences in serum concentrations of AMH between the studied groups. Studies with extended patient populations focusing on seminal plasma concentrations of AMH are warranted.  相似文献   
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Background Exploratory laparoscopy is commonly undertaken in patients with highly suspicious biliary and pancreatic lesions to facilitate diagnosis and staging cancer is present. If an unresectable tumor is identified, a second endoscopic procedure may be required do deploy a self-expandable metal stent (SEMS) for palliation. As endoscopic retrograde cholangio pancreatography (ERCP) may be unsuccessful in up to 20% of patients, we evaluated the feasibility and safety of deployment of self-expandable metal stents at the same time as the initial laparoscopy. Patients and Methods A total of 23 eligible patients (8 male and 15 female) with malignant obstruction of the common bile duct underwent deployment of SEMS at laparoscopy. Primary outcome measure was the successful laparoscopic deployment of stent and secondary outcome measure was complications rates. Results Indications for stent deployment were unresectable pancreatic cancer in 18, cholangiocarcinoma in two, neuroendocrine tumor in one and ampullary adenocarcinoma in two patients. The median age was 73 years (range 49–93). Twenty-two of 23 stents were deployed successfully: 17 stents were deployed transcystically and five via a choledochotomy. Median times for laparoscopic exploration and SEMS deployment were 165 min (range 105–230) and 20 min (range 10–50), respectively. Pre- and post-procedures median total bilirubin were 9.4 mg/dl (range 5.4–17.5) and 4.0 (range 2.6–7.1). The median size of the pancreatic mass was 3 cm (range 2–5 cm) and that of the common bile duct (CBD) from 9.2 mm (range 7.2–17.4). The mean duration of laparoscopy was 170 min (range 120–230 min) and that for stent deployment 23 min (range 10–50 min). Complications included bleeding, obstruction, and wound infection. Bleeding occurred on day 7 in two patients and on day 30 in one patient; bleeding occurred at the gastrojejunal anastomosis site and was successfully treated with endoscopic hemostasis. A total of three stent obstructions were identified: one each at 60, 90, and 120 days follow-up. All complications were successfully managed endoscopically. There were a total of seven deaths, six as a result of progressive cancer and one of surgical wound infection and ensuing complications. Conclusion This study demonstrates that laparoscopic deployment of self-expandable metal bile duct stents is feasible and safe. This option appears to be a reasonable option in patients with inoperable malignant obstruction of the distal common bile duct.  相似文献   
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Whole-heart cine MRI using real-time respiratory self-gating.   总被引:1,自引:0,他引:1  
Two-dimensional (2D) breath-hold cine MRI is used to assess cardiac anatomy and function. However, this technique requires cooperation from the patient, and in some cases the scan planning is complicated. Isotropic nonangulated three-dimensional (3D) cardiac MR can overcome some of these problems because it requires minimal planning and can be reformatted in any plane. However, current methods, even those that use undersampling techniques, involve breath-holding for periods that are too long for many patients. Free-breathing respiratory gating sequences represent a possible solution for realizing 3D cine imaging. A real-time respiratory self-gating technique for whole-heart cine MRI is presented. The technique enables assessment of cardiac anatomy and function with minimum planning or patient cooperation. Nonangulated isotropic 3D data were acquired from five healthy volunteers and then reformatted into 2D clinical views. The respiratory self-gating technique is shown to improve image quality in free-breathing scanning. In addition, ventricular volumetric data obtained using the 3D approach were comparable to those acquired with the conventional multislice 2D approach.  相似文献   
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PURPOSE: Biofeedback treatment is often offered to patients in colorectal centers; however, standards of treatment are still lacking. A dedicated team approach is desirable but difficult to coordinate. We present our three-year experience of electromyographic-based biofeedback treatment offered within a multicenter, statewide organization. METHODS: Between October 1992 and October 1995, 188 patients completed a biofeedback treatment program in one of five coordinated centers within a 200-mile radius. A unified common database was established and continuously updated. A colorectal surgeon served as statewide director, and dedicated teams were established at each location. Each local team included the medical director and a certified biofeedback therapist and had access to a dietitian and a nurse data coordinator. Electromyographic-based biofeedback sessions were given weekly, and a home trainer program was established. RESULTS: A total of 116 patients with chronic constipation had a mean of eight (range, 2–14) weekly sessions. A total of 72 patients with fecal incontinence had a mean of seven (range, 2–11) weekly sessions. A total of 84 percent of the constipated and 85 percent of the incontinent patients had significant improvement with biofeedback treatment. Patient compliance and satisfaction were high. Constipated patients increased the mean number of weekly unassisted bowel movements from 0.8 to 6.5. Incontinent patients decreased the mean number of weekly gross incontinence episodes from 11.8 to 2. CONCLUSIONS: Biofeedback treatment can be extremely successful in both incontinent and constipated patients. A large geographic area can be covered with coordinated centers in which each dedicated team uses a unified treatment protocol, and a common database is established.Poster presentation at the meeting of The American Society of Colon and Rectal Surgeons, Seattle, Washington, June 9 to 14, 1996.  相似文献   
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