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101.
NOTES transvaginal cholecystectomy: preliminary clinical application   总被引:19,自引:8,他引:19  
Background Natural orifice translumenal endoscopic surgery (NOTES) is an emerging concept in the recent literature that could lead to potential benefits in clinical applications. Restricted to animal experiments, however, human procedures have not yet been published. Because of the technical and ethical challenges involved in perforation and closure of a healthy organ—as is also seen in operating via the transgastric route—and because of the lack of understanding of the physiopathology and infection risk with these approaches, they have not been applied in the clinical setting. Thus the present study, based on previous animal experiments, describes preliminary clinical application in four cases of transvaginal NOTES cholecystectomy, and discusses safety, feasibility, and potential benefits of the method. Methods Preliminary acute and survival animal experiments developed by the NOTES Research Group at our institution solved such technical problems for transvaginal NOTES as spatial orientation, insufflation, and instrumentation, making possible the introduction of NOTES as a clinical application. The trials were approved by ethics committee of our institution, and informed consent was obtained from all patients. Since 13 March 2007, four female patients with elective surgical indication for cholecystectomy have undergone transvaginal NOTES cholecystectomy. All intraoperative and postoperative parameters were documented. Vaginal access was achieved under direct vision with conventional instruments, and a 2-channel colonoscope was inserted into the abdominal cavity. After endoscopic insufflation to achieve pneumoperitoneum with CO2, instruments were inserted through and alongside a colonoscope, allowing successful NOTES cholecystectomy in all patients, with vaginal extraction of the gallbladder. The vaginal wound was closed by direct vision using conventional instruments. Results The procedure was successful in all patients, with operative time of 45–115 min. Patients experienced low need for postoperative analgesia. Free oral intake was permitted 2 h after the procedure. There were no postoperative complications, and patients were discharged, according to the study protocol, 48 h after the procedure. Conclusions Preliminary results showed the feasibility and safety of the transvaginal NOTES method in this small initial study population. The technique, developed in our institution, and not transgastric NOTES, may be the preferred approach to serve as the basis for clinical studies.  相似文献   
102.
Adhesion molecules play a role in the migration of hematopoietic progenitor cells and regulation of hematopoiesis. To study whether the mobilization process is associated with changes in expression of adhesion molecules, the expression of CD31, CD44, L-selectin, sialyl Lewisx, beta 1 integrins very late antigen 4 (VLA-4) and VLA-5, and beta 2 integrins lymphocyte function-associated 1 and Mac-1 was measured on either bone marrow (BM) CD34+ cells or on peripheral blood CD34+ cells mobilized with a combination of granulocyte colony- stimulating factor (G-CSF) and chemotherapy. beta 1 integrin VLA-4 was expressed at a significantly lower concentration on peripheral blood progenitor cells than on BM CD34+ cells, procured either during steady- state hematopoiesis or at the time of leukocytapheresis. No differences in the level of expression were found for the other adhesion molecules. To obtain insight in which adhesion molecules may participate in the homing of peripheral blood stem cells (PBSCs), the number of CD34+ cells expressing these adhesion molecules present in leukocytapheresis material was quantified and correlated with hematopoietic recovery after intensive chemotherapy in 27 patients. The number of CD34+ cells in the subset defined by L-selectin expression correlated significantly better with time to platelet recovery after PBSC transplantation (r = - .86) than did the total number of CD34+ cells (r = -.55). Statistical analysis of the relationship between the number of CD34+L-selectin+ cells and platelet recovery resulted in a threshold value for rapid platelet recovery of 2.1 x 10(6) CD34+ L-selectin+ cells/kg. A rapid platelet recovery (< or = 14 days) was observed in 13 of 15 patients who received > or = 2.1 x 10(6) CD34+ L-selectin+ cells/kg (median, 11 days; range, 7 to 16 days), whereas 10 of 12 patients who received less double positive cells had a relative slow platelet recovery (median, 20 days; range, 13 to 37 days). The L-selectin+ subpopulation of CD34+ cells also correlated better with time to neutrophil recovery (r = - .70) than did the total number of reinfused CD34+ cells (r = -.51). However, this latter difference failed to reach statistical significance. This study suggests that L-selectin is involved in the homing of CD34+ cells after PBSC transplantation.  相似文献   
103.
Previous attempts to show a quantitative relationship between maternal hormone levels and early milk output have used small sample sizes and simple correlations. Women of mixed parity and similar socio-economic status and education were recruited to a study using multivariate analysis to look for these associations. Hormone levels (oestradiol, progesterone, prolactin and thyrotropin (TSH)) were determined for 91 mothers at four time points (ante- and postnatally) from finger-prick blood spots by fluoro-immunoassay. Milk output at 1 and 4 weeks was determined from 24-h test weighings. Parity was found to be the most significant factor affecting breast milk volume at 1 wk postpartum (multiparous women delivered 142 ml more milk in 24 h than primiparous women). Total time spent feeding had a strong association with breast milk volume, with increasing time having a negative effect. Multiple regression analysis, controlling for parity and time spent feeding, showed a positive association of milk output at 1 wk with antenatal progesterone and antenatal prolactin levels. At 4 wk, higher postpartum oestradiol levels had a negative association and antenatal progesterone levels a positive association with milk output. This study demonstrates that there are quantitative associations between antenatal maternal hormone levels and breast milk output in the early postnatal period.  相似文献   
104.
BACKGROUND: A good blood bank must be able to provide compatible blood units promptly to operating room patients with minimal wastage. A "self- service" by nursing staff blood banking system that is safe, efficient, and well-accepted has been developed. STUDY DESIGN AND METHODS: Specific blood units are no longer assigned to surgical patients who have a negative pretransfusion antibody screen, irrespective of the type of surgery. A computer-generated list of the serial numbers of all group-identical blood units currently in the blood bank inventory is provided for each patient. The units themselves are not labeled with a patient's name. The group O list will be provided for group O patients, the group A list for group A patients, and so forth. Should the patient require transfusion during surgery, the operating room nurses go to the refrigerator, remove any group-identical unit, and check the serial number of the unit against the serial numbers on the patient's list. If the serial number is on that list, the blood bank will accept responsibility for compatibility. The system was implemented in 1995. RESULTS: Since implementation, a total of 2154 patients have undergone operations at this hospital. Thirty-two patients received more than 10 units of red cells each. There were no transfusion errors. The crossmatch-to-transfusion ratio was reduced from 1.67 to 1.12. Turnaround time for supplying additional or urgent units to patients in operating room was shortened from 33 to 2.5 minutes. There was no incidence of a blood unit's serial number not being on the list. Work by nurses and technical staff was reduced by nearly 50 percent. CONCLUSION: The "self-service" (by nursing staff) blood banking system described is safe and efficient. It saves staff time and can be easily set up.  相似文献   
105.
Hatton  MW; Moar  SL; Richardson  M 《Blood》1988,71(5):1260-1267
The behavior of purified rabbit plasminogen at the luminal surface of the uninjured and deendothelialized rabbit aorta has been studied in vivo and in vitro. After intravenous injection, 125I-plasminogen associated rapidly with the endothelium (approximately 0.1 pmol/cm2 at saturation) and passed through to accumulate in the subendothelium. At two to 15 hours after injection, 11 to 15 times more radioactivity was associated with the subendothelium than with the endothelium. Removal of the endothelium by balloon catheter led to a rapid adsorption of 125I-plasminogen by the luminal surface of the vessel; saturation (9.1 pmol/cm2) was attained at ten to 20 minutes after deendothelialization. Of the adsorbed plasminogen (radioactivity), only 2% to 4% was associated with the adherent platelet monolayer. Uptake of 125I- plasminogen by the deendothelialized vessel was not significantly inhibited by epsilon-aminohexanoic acid whether injected before or after the 125I-plasminogen. No evidence of plasmin activity at the aorta surface was found from either transmission electron microscopy studies or from amidolytic assays of plasminogen-saturated deendothelialized aorta samples before or after urokinase treatment. Balloon catheter treatment in vivo, however, generated significant antiplasmin activity of the deendothelialized aorta surface. We conclude that plasmin formed in vivo is probably inactivated by the antiplasmin activity that is associated with the subendothelium.  相似文献   
106.
Thrombophilic factors in chronic thromboembolic pulmonary hypertension.   总被引:4,自引:0,他引:4  
Chronic thromboembolic pulmonary hypertension (CTE-PH) is an infrequent cause of pulmonary hypertension that develops in 0.1-0.2% of patients who survive after an acute venous thromboembolic event. According to the largest series so far reported, 15-30% of patients with diagnosis of CTE-PH have an underlying congenital or acquired hypercoagulable state. To determine the prevalence of thrombophilic factors in our population, we analyzed 24 patients admitted to our institution between November 1992 and March 2000 fulfilling criteria for CTE-PH. Eighteen patients disclosed abnormal results in the screening for thrombophilia. The presence of antiphospholipid antibodies (lupus anticoagulant and/or anticardiolipin antibodies) was the abnormality most frequently found (12 out of 24 patients). We found hyperhomocysteinaemia in 7/14, true protein S deficiency in 1/10, protein C deficiency in 1/13, activated protein C resistance in 1/22, antithrombin III deficiency in 1/24, and prothrombin gene G20210A mutation in 1/18 patients. Factor V Leiden was normal in all 18 patients studied. Five patients (20.8%) disclosed more than one thrombophilic abnormality. In conclusion, contrary to the largest series of patients with CTE-PH so far reported, we found that 75% of patients with CTE-PH presented at least one thrombophilic risk factor, being antiphospholipid antibodies in 50% of the cases. We recommend a thorough screening for thrombophilia in all patients with diagnosis of CTE-PH.  相似文献   
107.
108.
A plasma fibronectin-rich component was prepared by heparin-induced 4 degrees C precipitation of fresh or stored (21 days at 4 degrees C), single-donor plasma. The recovery of plasma fibronectin was 45 percent at a concentration of 0.05 mg heparin per ml (7.5 units/ml) and 75 percent at 0.1 mg per ml (15 units/ml). The biologic activity of plasma fibronectin, as assessed by the spreading of Chinese hamster ovary cells or attachment of monocytes to gelatin-coated surfaces, was similar to that of plasma fibronectin concentrates made from fresh or stored plasma. Only 20 to 30 percent of the factor VIII activity in fresh plasma was recovered in cryoprecipitate produced after the heparin-induced precipitate containing fibronectin was removed. Cryoprecipitate prepared from the supernatant plasma that remains after heparin-induced cold precipitation in the presence of CaCl2 (5 mM) contained approximately 50 percent less factor VIII. The relatively low recovery of factor VIII in cryoprecipitate prepared from fibronectin-depleted plasma makes cryoprecipitation an unsuitable method of producing fibronectin-rich and factor VIII-rich components effectively from a single unit of fresh plasma. However, heparin-induced cold precipitation provides an efficient method for preparing plasma fibronectin concentrates from small plasma pools or single units of stored or fresh plasma.  相似文献   
109.

Background  

Studies show that tuberculosis notification declines with increasing altitude. This can be due to declining incidence or declining case detection. In Vietnam notification rates of new smear-positive tuberculosis in the central mountainous provinces (26/100,000 population) are considerably lower than in Vietnam in general (69/100,000 population). In order to clarify whether this is explained by low incidence or low case detection, we aimed to assess the prevalence of new smear-positive tuberculosis among adults with prolonged cough in three mountainous provinces in central Vietnam.  相似文献   
110.
Herpesvirus-like DNA sequences (KSHV/HHV-8) have recently been described in AIDS-associated Kaposi's sarcoma (KS) lesions. Many questions remain regarding the role of this virus in KS and the therapeutic implications of this finding. In the current study, KSHV/HHV-8 DNA was detected in peripheral blood mononuclear cells (PBMCs) from human immunodeficiency virus (HIV)-infected patients with KS (34/98) more often than in HIV-infected individuals without KS (12/64, P = .03). The detection of KSHV/HHV-8 DNA did not correlate with the CD4 lymphocyte count. Five patients demonstrated KSHV/HHV-8 DNA in their PBMCs during administration of intravenous foscarnet and/or ganciclovir. The continued detection of KSHV/HHV-8 DNA in the PBMCs of patients receiving these anti-herpesvirus drugs has potential implications regarding the virus-cell relationship of KSHV/HHV-8, as well as for the value of these drugs in treating or preventing KS, but additional studies are needed.  相似文献   
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