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11.
Background: Expanding upon our experience with laparoscopic surgery for colonic benign and malignant processes and for bowel obstruction, we have reviewed our experience with minimal access laparoscopic surgery for complicated diverticular disease. We propose an approach of surgical care incorporating diagnostic laparoscopy in those not responding to medical therapy alone. Methods: Our study includes data from two different surgical teams working in separate hospital-and-patient environments. Our theory that laparoscopy could be widely applicable to this complex disease process is borne out by experience in both locations. One hundred forty-eight patients were managed by laparoscopic or laparoscopically assisted methods with 18 patients requiring drainage only without resection. Results: Our management of 148 of 164 patients (90%) by laparoscopic approach was successful, with a very acceptable morbidity of 5% in the elective cases and decreased ileus (20% of open vs 7% laparoscopic) in acute complicated cases. Elective resections required hospitalization of 4–5 days, demonstrating the benefits of incorporating laparoscopy in the care of these cases, particularly when compared to standard open procedures requiring 8 days' hospitalization. Conclusions: We believe complications of diverticular disease including abscess, perforation, fistula, and bleeding can potentially be managed in this way by minimal access procedures, decreasing postoperative wound problems, decreasing length of hospitalization and overall morbidity, and improving patient care.  相似文献   
12.
BACKGROUND: There are obvious advantages to increasing donor retention. However, for reasons of blood safety, certain donors may, in fact, be more desirable to retain than others. “Safe” donors are defined as those who provided a blood donation that was negative on all laboratory screening tests and who subsequently reported no behavioral risks in response to an anonymous survey. This study identifies the most important factors affecting the intention of “safe” donors to provide another donation. STUDY DESIGN AND METHODS: An anonymous survey asking about donation history, sexual history, injecting drug use, and recent donation experience was mailed to 50,162 randomly selected allogeneic donors (including directed donors) who gave blood from April through July or from October through December 1993 at one of the five United States blood centers participating in the Retrovirus Epidemiology Donor Study. Before mailing, questionnaires were coded to designate donors with nonreactive laboratory screening tests at their most recent donation. RESULTS: A total of 34,726 donors (69%) responded, with substantially higher response among repeat donors. According to reported intentions only, the vast majority of “safe” donors indicated a high likelihood of donating again within the next 12 months. Only 3.4 percent reported a low likelihood of donating again. A comparison of those likely to return and those unlikely to return reveals significant differences in demographics and in ratings of the donation experience. A higher proportion of those unlikely to return were first-time donors, minority-group donors, and donors with less education. The highest projected loss among “safe” donors was seen for those who gave a fair to poor assessment of their treatment by blood center staff or of their physical well-being during or after donating. CONCLUSION: These data suggest that efforts to improve donors' perceptions of their donation experience, as well as attention to the physical effects of blood donation, may aid in the retention of both repeat and first-time donors.  相似文献   
13.
We compared the results of a radiographic technique for the measurement of instability of the knee with those obtained with a KT-1000 arthrometer. The study was conducted on both knees of sixty patients who had a ruptured anterior-cruciate ligament in one knee, as well as in ten control subjects. The radiographic technique included the examination of a true lateral radiograph, made while the knee was in full extension and the quadriceps was maximally contracted, with a 66.7-newton downward force produced by a 6.8-kilogram weight suspended from the ankle. As demonstrated by both techniques, the maximum difference between the displacements of the right and left knees in the control subjects was 2.5 millimeters and the mean difference between the displacements in the two knees in the patients was 7.5 millimeters. In fourteen of the sixty knees in which the ligament was ruptured, the injury was acute. The forward translation of the medial side in these fourteen knees was compared with that in the forty-six knees in which the injury was chronic. The mean difference in the displacement of the medial side in the right and left knees was 3.5 millimeters in the fourteen patients who had an acute injury and 5.0 millimeters in the forty-six patients who had a chronic injury. Thirteen of the sixty patients had disruption of the posteromedial corner of the injured knee, and the translation of the medial side in these knees was significantly increased compared with that in the intact knees of the same patients.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
14.
15.
The protective effects of a series of stable adenosine analogs against generalized seizures initiated by focal injection of bicuculline methiodide into the rat prepiriform cortex (PPC) were studied by microinjection of these compounds into this brain area. The adenosine agonists, 5'-N-(ethyl)carboxamido-adenosine (NECA), cyclohexyladenosine, cyclopentyadenosine, 2-chloroadenosine and R- and S-phenylisopropyladenosine (R- and S-PIA), protected animals against seizures in a dose-dependent, and extremely potent manner. NECA, the most potent compound evaluated, completely prevented seizures at doses greater than or equal to 6.8 pmol. In contrast, heroic doses of the A2 selective ligand, 2-phenylaminoadenosine, afforded no protection against seizures. The rank order of potency of these compounds in suppressing seizures is as follows: NECA greater than cyclohexyladenosine greater than cyclopentyladenosine greater than or equal to R-PIA greater than 2-chloroadenosine greater than S-PIA much greater than 2-phenylaminoadenosine. These data suggest that the antiseizure activity of these compounds in the PPC results from activation of A1 adenosine receptors. Quantitative autoradiographic analysis of the distribution of tritiated adenosine agonists 30 min after microinjection in the PPC reveals that [3H]NECA diffuses to a significantly greater extent than R-[3H]PIA, which may contribute to the relatively greater potency of the former compound in suppressing bicuculline methiodide-induced seizures. These results suggest that adenosine A1 receptors may participate in the normal inhibitory regulation of the PPC, a forebrain area which may play a significant role in the pathobiology of epilepsy.  相似文献   
16.
Conclusions In conclusion, this team emphasizes that the technology must not get in the way of the anesthesiologist having contact with the patient. The technology should function as transparently as possible.  相似文献   
17.
Background: A survival disadvantage for black women with brest cancer, which persists after controlling for stage of the disease, has been reported. This study investigates the effects of race and socioeconomic status (SES) on breast cancer survival after controlling for age, stage, histology, and type of treatment. Methods: Kaplan-Meier and Cox proportional hazards models were used to analyze the interaction between race and SES in predicting survival in a sample of 163 black, 205 Hispanic, and 964 white women with breast cancer treated at M. D. Anderson Cancer Center (1987–1991). Results: The results of univariate and multivariate analyses indicate that race was not a significant predictor of survival after adjusting for SES and other confounding factors such as demographic and disease characteristics. SES remained a significant predictor of survival after all adjustments were made. There was no evidence of differences in type of treatment by race or SES if adjustments were made for stage. Conclusions: These results suggest that institutional factors, such as access to treatment, do not explain survival differences by race or SES. Other factors associated with low SES, such as life-style and behavior, may affect survival.  相似文献   
18.
A temperature probe based on the magnetic resonance properties of an encapsulated liquid crystal has been investigated. Large changes in magnetic resonance signals occur as the liquid crystal undergoes a phase transition from an anisotropic (nematic) state to the isotropic liquid. The low latent heat of such phase transitions allows for rapid phase changes during a hyperthermia treatment. Transition temperatures can be tailored by adding suitable compounds such as analogues of the liquid crystal or various solvents. Encapsulation is required to maintain the integrity of the liquid crystal, particularly for applications in vivo. Results of preliminary studies designed to demonstrate the technical feasibility of the concept are presented.  相似文献   
19.
Summary In order to evaluate whether base modifications, apurinic/apyrimidinic site formation, strand breaks, or a combination of these lesions results from the interaction of glycation products with DNA, plasmid DNA was first reacted with these products, and then subjected to digestion with endonuclease III and endonuclease IV of Escherichia coli. Analysis of the differential effects of digestions with these enzymes by electrophoresis on agarose gels demonstrated that reactive glycation products produce both base modification and apurinic/apyrimidinic sites in DNA, in addition to the strand breaks observed after incubation with glycation products alone. These types of DNA damage may occur in specific diabetic cells where elevated levels of glycating sugars are associated with pathologic dysfunction. [Diabetologia (1994) 37: 145–149] Received: 28 May 1993 and in revised form: 30 August 1993  相似文献   
20.
The sensitivity of non-isotopic in situ hybridization (NISH), particularly on formalin-fixed, paraffin-embedded (FFPE) clinical tissues, has been the subject of controversy. Generally, NISH has been regarded as being less sensitive than radiolabelled procedures, although some reports have contradicted this. Accordingly, tissues from mice which were transgenic for variable amounts of the human alpha-1-antitrypsin gene were used to optimize the NISH procedure and to estimate the sensitivity. This approach showed that prolonged incubation of slides in final substrate resulted in high sensitivity--about 13 kb of target DNA. However, this prolonged incubation crucially depended on achieving minimal non-specific background staining. Many factors affected the degree of background staining, but five were particularly important. First, the method of mounting cut sections onto slides. Second, the length of the probe (ideally less than 400 bp). Third, the procedure for proteolytic digestion. Fourth, the denaturation technique, and fifth, the quality of the dextran sulphate used in the hybridization mix. The optimized protocol showed variable patterns of mRNA distribution in the transgenic mouse livers, while DNA distribution appeared uniform.  相似文献   
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