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1.
Njideka U Okubadejo James H Bower Walter A Rocca Demetrius M Maraganore 《Movement disorders》2006,21(12):2150-2156
Parkinson's disease (PD) occurs worldwide, but little is known about PD in Africa. We systematically reviewed publications on PD in Africa, with emphasis on epidemiologic and genetic studies. Articles published between 1944 and December 2004 were identified using several strategies. The studies emanated from 13 African countries (Kenya, Uganda, Tanzania, Ethiopia, Nigeria, Senegal, Ghana, Togo, Libya, Tunisia, Algeria, Zimbabwe, and South Africa). The publications fell into four categories: clinical series (n = 17), prevalence studies (n = 7), incidence studies (n = 1), and genetic studies (n = 3). The clinical series documented the occurrence of PD in Africa and described its clinical characteristics. The prevalence studies suggested some intracontinental geographic variation in PD prevalence. Overall, the prevalence figures and the incidence rates of PD in Africa appeared lower than those reported for European and North American populations. Few genetic studies of PD have been reported from Africa, and none in blacks. There are no case-control or cohort studies of PD reported from Africa. This review provides a summary of PD research in Africa over the past 60 years and highlights the information gaps and potential areas for future research. 相似文献
2.
Demetrius M Maraganore Matthew J Farrer Timothy G Lesnick Mariza de Andrade James H Bower Dena Hernandez John A Hardy Walter A Rocca 《Movement disorders》2003,18(11):1233-1239
We conducted a case-control study of the alpha-synuclein-interacting protein gene (SNCAIP, also known as synphilin-1) and Parkinson's disease (PD). A total of 319 PD cases and 195 controls were genotyped for four SNCAIP variants, including a microsatellite repeat in intron 4 and three restriction fragment length polymorphisms (RFLP) proximal to the 5' terminal of exons 1, 4, and 6. None of the variants were found associated with PD overall. Global score statistics were not significant for four, three, and two loci haplotypes. All four loci were in linkage disequilibrium for cases, controls, or both groups combined (P < 0.0001). Recursive partitioning showed no interactions between variants of the SNCAIP gene and variants of the alpha-synuclein gene (SNCA) or the parkin (PARK2) gene. 相似文献
3.
Transbronchial needle aspiration (TBNA) was performed as a diagnostic procedure in 91 consecutive patients ultimately proven to have bronchogenic carcinoma. Results of TBNA were compared, in the same patients, to the diagnostic yield of cytologic examination of sputum, endobronchial brushings and washings, and endobronchial/transbronchial biopsy. The diagnostic yield for sputum was 13 percent (10 of 75); brushings, 40 percent (34 of 84); washings, 29 percent (26 of 89); biopsy, 56 percent (42 of 75); and TBNA, 45 percent (41 of 91). Aspirates were positive in 35 percent of patients with adenocarcinoma, 41 percent with squamous cell carcinoma, 52 percent with large cell undifferentiated carcinoma, and 55 percent of patients with small cell carcinoma. Carinal aspirates were positive in 54 percent (6 of 11); paratracheal aspirates, 57 percent (13 of 23); parabronchial aspirates, 39 percent (11 of 28); endobronchial, 78 percent (7 of 9), and peripheral mass or solitary pulmonary nodule, 40 percent (17 of 42). The overall diagnostic yield for brushings, washings, and biopsy was 64 percent. The addition of TBNA increased the yield to 71 percent. Bronchogenic carcinoma was diagnosed solely by TBNA in six patients, all with extrabronchial or extratracheal lesions. We conclude that TBNA increases the diagnostic yield of bronchoscopy, particularly in patients with extratracheal and extrabronchial lesions. An equally important observation is that TBNA fails to contribute significantly to the diagnosis of cancer in patients with lesions readily accessible by conventional bronchoscopic techniques. Exceptions to this observation include occasional patients with necrotic endobronchial tumors, submucosal lesions, and rarely patients with peripheral lung nodules or masses. 相似文献
4.
Sequential contrast-enhanced MR imaging of the penis 总被引:1,自引:0,他引:1
5.
Acquired and innate resistance to the haemoflagellate cryptobia salmositica in sockeye salmon (Oncorhynchus nerka) 总被引:2,自引:0,他引:2
Juvenile sockeye salmon (Oncorhynchus nerka, Fulton River stock) were protected from otherwise lethal challenges with the haemoflagellate Cryptobia salmositica by acclimation to elevated water temperatures (20 degrees C). Fish treated in this manner displayed increased immunity to C. salmositica and yielded plasma showing enhanced lytic activity against the parasite. The acquired lytic activity was antibody- and complement-mediated. In contrast, a stock of naive O. nerka from Weaver Creek, previously identified as having a high innate resistance to the lethal effects of C. salmositica, also had plasma factors that destroyed the parasite in vitro. This anti-Cryptobia activity also involved complement because 1) it resulted in lysis of the parasite, 2) it was heat-labile (40 degrees C for 20 min), and 3) it was largely removed from the plasma by substances capable of activating (binding) complement by the classical pathway (an antigen:antibody complex of Renibacterium salmoninarum and its specific antibody) and the alternate pathway (Escherichia coli lipopolyssacharide). The complement-mediated lysis associated with innate resistance was apparently the result of activation by the alternate pathway because it occurred in fish lacking antibodies against the parasite. The reaction was unusual in that a long incubation period (about 2 days) was required for maximum lysis of the parasite. At least one component of the innate lytic system depended on disulphide bonds because lytic activity was destroyed by 2-mercaptoethanol. 相似文献
6.
Juvenile sockeye salmon (
, Fulton River stock) were protected from otherwise lethal challenges with the haemoflagellate
by acclimation to elevated water temperatures (20°C). Fish treated in this manner displayed increased immunity to
.
and yielded plasma showing enhanced lytic activity against the parasite. The acquired lytic activity was antibody- and complement-mediated. In contrast, a stock of naive
.
from Weaver Creek, previously identified as having a high innate resistance to the lethal effects of
.
, also had plasma factors that destroyed the parasite
. This anti-
activity also involved complement because 1) it resulted in lysis of the parasite, 2) it was heat-labile (40°C for 20 min), and 3) it was largely removed from the plasma by substances capable of activating (binding) complement by the classical pathway (an antigen:antibody complex of
and its specific antibody) and the alternate pathway (
lipopolyssacharide). The complement-mediated lysis associated with innate resistance was apparently the result of activation by the alternate pathway because it occurred in fish lacking antibodies against the parasite. The reaction was unusual in that a long incubation period (about 2 days) was required for maximum lysis of the parasite. At least one component of the innate lytic system depended on disulphide bonds because lytic activity was destroyed by 2-mercaptoethanol. 相似文献
7.
Tunnelled silicone rubber right atrial catheters are commonly used to administer long-term total parenteral nutrition (TPN), cancer chemotherapeutic agents, and antimicrobial agents. The indwelling devices potentiate platelet-fibrin thrombi formation, providing a nidus for infection. Although many episodes of sepsis associated with thrombotic tunnelled catheters respond to antimicrobial therapy alone, a significant number require catheter removal. Evidence from case studies and small clinical trials suggests that fibrinolytic agents may increase the response rate and prevent removal of the device when combined with antimicrobial therapy. We present the first case reported of bacterial sepsis secondary to a thrombotic indwelling Hickman catheter for long-term TPN successfully treated with a combination of streptokinase and antibiotic therapies. 相似文献
8.
U.M. Hodges BSc Hons MBBS FRCA S. Berg BSc MBBS FRCA S.K. Naik FRCS S. Bower MBChB PhD A. Lloyd-Thomas MBBS FRCA M. Elliot MD FRCS 《Journal of cardiothoracic and vascular anesthesia》1994,8(6)
Modified ultrafiltration after cardiopulmonary bypass in children has been shown to be associated with an increase in arterial blood pressure. As part of a series of studies to investigate the possible causes of this blood pressure elevation, the hypothesis that if filtration was removing a significant amount of fentanyl, then the increase in blood pressure might be due to pain was proposed. Ten children, aged between 0.5 and 9.3 years (median 3.8 years), weighing 5.9 to 25..5 kg (median 15.7 kg), underwent corrective cardiac surgery (incorporating modified ultrafiltration). A standard anesthetic protocol was followed, with up to 78 μg/kg of fentanyl given prebypass for analgesia. After completion of cardiopulmonary bypass, modified ultrafiltration was commenced at 100 mL/min until a hematocrit of 35% was reached. Samples were taken of arterial blood (prefiltration, 3, 10, and 20 minutes postfiltration), the venous reservoir blood (prefiltration) and the filtrate (5 and 10 minutes into filtration). Hemodynamic data were recorded both prefiltration and postfiltration. The hemodynamic data showed the expected rise in both systemic arterial pressure and cardiac index after ultrafiltration. The plasma fentanyl concentrations did not significantly change after ultrafiltration: 1.59 to 12.39 ng/mL (median 6.27 ng/mL) prefiltration and 2.05 to 15.59 ng/mL (6.29 ng/mL) at 3 minutes, 2.22 to 12.64 ng/mL (6.87 ng/mL) at 10 minutes, and 1.83 to 11.52 ng/mL (5.85 ng/mL) at 20 minutes postfiltration. The concentration of fentanyl in the venous reservoir, 2.06 to 11.64 ng/mL (7.04 ng/mL), was not significantly different from the plasma levels. The level of fentanyl in the filtrate was significantly less than the plasma levels, 0.243 to 1.87 ng/mL (0.894 ng/mL) at 5 minutes and 0.385 to 1.688 ng / mL (0.952 ng / mL) at 10 minutes into filtration; (P < 0.02 by the Wilcoxon signed-rank method). The data show that the plasma fentanyl concentration was not significantly reduced by modified ultrafiltration. The fentanyl levels found prefiltration were maintained postfiltration, and the observed changes in systemic arterial pressure were not due to an acute fall in the plasma concentration of analgesic drug. 相似文献
9.
Genotype-phenotype correlation for nucleotide substitutions in the IgII- IgIII linker of FGFR2 总被引:6,自引:3,他引:3
10.
D. D. Coster W. H. Bower V. T. Wilson R. T. Brebrick G. L. Richardson 《Surgical endoscopy》1997,11(6):625-631
Background: Since 1992, all patients at our institution who have met standard accepted criteria for surgical intervention for complicated
gastroesophageal reflux disease have been entered into a prospective sequential clinical study to evaluate outcomes of the
laparoscopic approach to the Nissen-Rosetti procedure and a modified Toupet procedure.
Methods: A standardized workup with upper GI series, esophagography, and endoscopy was used in all patients. Manometry, pH testing,
and other special tests were used selectively. A measuring technique was used to determine wrap size without the use of dilators.
The short gastric vessels were left intact in all patients. A cosurgeon approach was used, with technical factors described
herein.
Results: Some 226 of 231 cases were completed laparoscopically (98%)—125 patients in the Nissen-Rosetti group and 101 in the partial
fundoplication group. There were no clinical failures in either group. The partial fundoplication group performed better than
the Nissen-Rosetti group in all categories of comparison. Return to normal eating habits was much earlier in the partial wrap
group (p < 0.0001). Postop distal esophageal sphincter pressures in the two groups were equal at 15 mmHg. Eight patients suffered
significant dysphagia requiring endoscopy and dilatation, all in the Nissen-Rosetti group (p < 0.01). Minor complications occurred in 12% of the total group. There was a total surgical revision rate of 3%. There were
no gastric or esophageal perforations. Average operative time was 30 min. Average hospital stay was 1.4 days. Hospital charges
for the laparoscopic approach averaged $6,000 dollars compared to $12,000 for the open approach.
Conclusion: Laparoscopic partial fundoplication is as effective as laparoscopic Nissen-Rosetti fundoplication, with a higher satisfaction
rate and fewer side effects. Measuring for wrap and hiatus size eliminates the need for and risk of using stiff dilators.
By utilizing cosurgeons and currently available technology, cost, operative time, hospital time, and complications can be
reduced to a finite minimum.
Received: 12 December 1995/Accepted: 12 August 1996 相似文献