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951.
OBJECTIVE: To determine the feasibility of intraoperative radioisotopic mapping using an endoscopic gamma probe associated with patent blue dye injection in patients with early stage cervical cancer. METHODS: Between April 2001 and March 2002 a total of 12 patients underwent laparoscopic bilateral pelvic lymphadenectomy (squamous carcinoma in 10 cases, all stage FIGO IB1, and adenocarcinoma in 2 cases, stages IA2 and IB1). Lymphoscintigraphies were performed on the day before surgery to visualize sentinel lymph nodes, 31 +/- 22.5 and 174 +/- 34 min after injection of 200 microCi of technetium 99m rhenium sulfur colloid. The marker was injected at the 3, 6, 9, and 12 o'clock positions. The day of surgery 2 ml of patent blue dye plus 2 ml of physiological serum was injected in the cervix, at the same locations as the radioactive isotope injection. RESULTS: A total of 35 sentinel lymph nodes were detected. Eight sentinel lymph nodes were only detected by color, 8 sentinel lymph nodes were only detected by the endoscopic gamma probe, and 19 sentinel lymph nodes were "hot and dyed." We found 3 metastatic lymph nodes. In one case, bilateral positive sentinel nodes were only detected by the endoscopic gamma probe. Permanent section identified one inframillimetric micrometastasis in a lymph node that was neither blue nor hot intraoperatively (sensitivity = 66%, specificity = 100%, positive predictive value = 100%, negative predictive value = 90%). CONCLUSION: The identification of the sentinel lymph node with blue dye and radioisotope using an endoscopic gamma probe is feasible and improves detection rate. False negatives still occur, but the proportion is low even at the beginning of the learning curve. Isotopic imaging identifies nodes in areas outside the pelvis not routinely sampled in early cervical cancer patients.  相似文献   
952.
In cardiac myocytes of new-born rats, the degree of intercellular communication through gap junctional channels closely depends on the metabolic state of the cells. In contrast, in stably transfected HeLa cells expressing rat cardiac connexin43 (Cx43, the main channel-forming protein present in ventricular myocytes), a major part of junctional communication persisted in ATP-depleted conditions, in the presence of a metabolic inhibitor (KCN) or of a broad spectrum inhibitor of protein kinases (H7). However, another metabolic inhibitor, antimycin A, which like cyanide inhibits electron transfer in the respiratory chain, totally interrupted cell-to-cell communication between Cx43-HeLa cells, even in whole-cell conditions, when ATP (5 mM) was present. Antimycin A caused a modest increase in cytosolic calcium concentration; however, junctional uncoupling still occurred when this rise was prevented. Conditions of ischemic insult (e.g. ischemia or chemical hypoxia) frequently cause the activation of protein kinases, particularly of Src and MAP kinases, and such activations are known to markedly disrupt gap junctional communication. Antimycin-induced junctional uncoupling occurred even in the presence of inhibitors of these kinases. Antimycin A appears able to cause junctional uncoupling either through the ATP depletion it induces as a metabolic poison or via a direct action on gap junction constituents.  相似文献   
953.
OBJECTIVE: Nerve-sparing dissection of the lateral portion of the cardinal ligament (paracervical lymphadenectomy) has been recently developed with the goal of reducing the late urinary adverse effects of radical hysterectomy without impairing the outcome. This work has been carried out in order to investigate the influence of additional paracervical lymph node dissection at the time of laparoscopically assisted modified radical hysterectomy on outcome and urinary sequelae. METHODS: A total of 95 patients underwent a modified radical hysterectomy using a combined laparoscopic and vaginal approach since 1991. In 47 of these patients treated since 1996 an additional laparoscopic paracervical lymphadenectomy was performed. The operative, postoperative, and survival outcomes were assessed. In 60 patients, 32 and 28 in the groups of patients with or without paracervical dissection, respectively, a careful interview on urinary symptoms was conducted by an independent investigator. RESULTS: Paracervical dissection involves no operative complication and lenghthens the postoperative urinary retention, but has no adverse influence on long-term urinary discomfort. The yield of paracervical dissection is negligible for small tumors: no positive node was found in 38 patients with tumors less than 2 cm in diameter. The outcome of patients after minimal access surgery for tumors less than 2 cm is excellent whether or not a paracervical dissection has been performed. CONCLUSION: Paracervical dissection does not worsen the late urinary symptoms after vaginal radical hysterectomy. It has a limited value in the surgical management of small-size (less than 2 cm) cervical cancers, although it may prevent long-term lateropelvic recurrences.  相似文献   
954.
OBJECTIVE: The purpose of this pilot study was to document speech perception and localization abilities in patients who use a cochlear implant in one ear and a hearing aid in the other ear. DESIGN: We surveyed a group of 111 cochlear implant patients and asked them whether they used a hearing aid on their unimplanted ear. The first three patients who were available were tested on word and sentence recognition and localization tasks. Speech stimuli were presented from the front in quiet and in noise. In the latter conditions, noise was either from the front, the right, or the left. Localization was tested with noise bursts presented at 45 degrees from the right or left. In addition we asked the patients about their abilities to integrate the information from both devices. RESULTS: Speech perception tests in quiet showed a binaural advantage for only one of the three patients for words and none for sentences. With speech and noise both in front of the patient, two patients performed better with both devices than with either device alone. With speech in front and noise on the hearing aid side, no binaural advantage was seen, but with noise on the cochlear implant side, one patient showed a binaural advantage. Localization ability improved with both devices for two patients. The third patient had above-chance localization ability with his implant alone. CONCLUSIONS: A cochlear implant in one ear and a hearing aid in the other ear can provide binaural advantages. The patient who did not show a clear binaural advantage had the poorest hearing aid alone performance. The absolute and relative levels of performance at each ear are likely to influence the potential for binaural integration.  相似文献   
955.
956.
Most countries in oriental Asia have not yet experienced the 'western' coronary heart disease (CHD) epidemic despite substantial economic development. An exception has been Singapore. We compared mortality and CHD risk factors in Singapore with two Oriental locations, Hong Kong and mainland China, which have not experienced the CHD epidemic. Mortality data from World Health Statistics Annuals age standardised for each location and were supplemented by local data. Risk factor data was obtained from population-based surveys using similar protocols in each location. Measures included diet, blood lipids, blood pressure, height and weight. CHD mortality in the year chosen for comparison, 1994, was significantly higher for Singapore Chinese males [108 (95.2-119.1)] than Chinese males in Hong Kong [44.3 (40.2-48.2)] or China [45.5 (44.2-46.8)]. Female CHD mortality was also relatively higher in Singapore Chinese. The only CHD risk factor markedly higher in Singapore Chinese was serum cholesterol; Singapore males [5.65 (5.55-5.75)], females [5.60 (5.50-5.70)], Hong Kong males [5.21 (5.11-5.31)], females [5.20 (5.10-5.29)] and China males [4.54 (4.46-4.62)], females [4.49 (4.42-4.55)]. Dietary differences in saturated fat consumption were consistent with this. Although there was little difference in total fat intake, a higher consumption of dietary saturated fat and lower consumption of polyunsaturated fat, accompanied by higher serum cholesterol, appear to explain the relatively high CHD mortality in Singapore compared with Hong Kong and mainland China. Differences in body mass index, blood pressure and smoking between locations did not explain the differences in CHD mortality.  相似文献   
957.
The bactericidal activities of ciprofloxacin, ofloxacin, levofloxacin, moxifloxacin, and gatifloxacin were tested in three models of rifampin-tolerant Mycobacterium tuberculosis persisters. Model 1 was a 100-day-old, unshaken, anaerobically adapted culture in which serial dilutions of the quinolones were incubated for 5 days and CFU counts were then done In models 2 and 3, 100 mg of rifampin/liter was added to the 100-day culture for 5 or 7 days to produce tolerant organisms that did not grow on plates; the rifampin was then washed off, fresh medium was added to allow recovery of growth on plates, and the culture was incubated for 7 days before CFU counts. In model 2, the quinolones were added after rifampin had been washed off, whereas in model 3 the quinolones were added to the cultures containing rifampin. In models 1 and 2, ciprofloxacin had the least bactericidal activity, ofloxacin and levofloxacin had greater activities, and moxifloxacin and gatifloxacin had the greatest activities. In model 3, ofloxacin had no detectable activity whereas moxifloxacin killed about log(10) 0.279 CFU of the persisters per ml at concentrations attainable in lesions; isoniazid had virtually no activity. These findings predict that ofloxacin will not be found to have effective sterilizing activity in clinical studies now planned whereas moxifloxacin will be able to shorten treatment.  相似文献   
958.
This study's objective was to determine the effect of paramedic experience on orotracheal intubation success in prehospital adult nontraumatic cardiac arrest patients. This retrospective study analyzed all attempted intubations of prehospital adult nontraumatic cardiac arrest patients between January 1, 1997 and April 30, 1997 in an urban, all ALS service. Data were abstracted from EMS reports and intubation data forms. Variables included months of experience, number of patients in whom intubation was attempted, number of intubation attempts, success per attempt, and success per patient. Ninety-eight paramedics performed 909 intubations on 1066 cardiac arrest patients, yielding an intubation success rate of 85.3%. The median months of experience was 59.5 (Range 5-223). The median number of patients in whom intubation was attempted per paramedic was 10 (Range 1-36). The mean intubation success rate per paramedic was 80.6% (+/- 22.4, 95% CI 76.1, 85.1). There was significant correlation between total number of patients in whom intubation was attempted and intubation success rate (p <.001, R = 0.32). There was no correlation between months of experience and intubation success rate. In conclusion, the number of patients in whom intubation was attempted per paramedic was significantly correlated with the intubation success rate. Months of experience per paramedic had no significant correlation with intubation success rate.  相似文献   
959.
alpha-2-macroglobulin (alpha-2-M), a plasma proteinase inhibitor, plays an important role in the pathogenesis of lung inflammation. The purpose of this study was to develop a sensitive ELISA assay for rabbit alpha-2-M to allow us to define the role of this protein in a rabbit model of lung inflammation/injury. Therefore, we developed hybridomas which secrete monoclonal antibodies (mAbs) against rabbit alpha-2-M. From the antibodies produced, two (5B6 and 3C5) were selected. Both of them were of the IgG1 subclass. 5B6 reacted with native alpha-2-M as well as with the "fast" form of alpha-2-M (native alpha-2-M or the "slow" form is converted to the "fast" form by reaction with a proteinase). On the other hand, 3C5 reacted only with "fast" form of alpha-2-M. With these antibodies, we developed two ELISA assays which were used to determine the concentration of alpha-2-M in the lung fluids from rabbits with lung injury.  相似文献   
960.
The distributions of the antibiotic resistance patterns in a population of Staphylococcus aureus isolates from a teaching hospital were studied over a 9-year period. The results indicate the existence of successive major epidemic methicillin-resistant strains and the emergence of a methicillin-susceptible strain with an unusual resistance pattern. Our findings suggest that this methicillin-susceptible S. aureus strain could be derived from the dominant gentamicin-susceptible methicillin-resistant S. aureus strain with the loss of a 40-kb DNA fragment.  相似文献   
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