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71.
BACKGROUND/AIMS: Primary carcinoma of the gallbladder is rare and associated with a late diagnosis and poor prognosis. Concurrent acute cholecystitis frequently obscures the presence of carcinoma. The information regarding gallbladder carcinoma with acute cholecystitis is limited. In order to better understand the presentation of gallbladder carcinoma with acute cholecystitis, we retrospectively reviewed the data of patients with primary carcinoma of the gallbladder. METHODOLOGY: The data of 86 patients with primary carcinoma of the gallbladder treated between 1979 and 1994 were compiled and reviewed. The patients were divided into 2 groups: Group 1 (with acute cholecystitis, 21 patients) and Group 2 (without cholecystitis, 65 patients). Clinicopathological comparisons were made and evaluated between these two groups RESULTS: The average age of Group 1 patients was older than that of Group 2 patients (75+/-2 years vs. 63+/-2 years; p<0.05). Three Group 1 patients presented with sepsis. The interval between the onset of symptoms and hospital admission in Group 2 patients was significantly (p<0.05) longer than that in Group 1 patients (243+/-95 days vs. 20+/-11 days). Leukocytosis (>11,000/mm3) was more common in Group 1 patients than in Group 2 patients (47.6% vs. 15.4%). Jaundice was more common in Group 2, and fever was common in Group 1. The majority of Group 2 gallbladder cancers were stage V (75.4%). In contrast, 52.4% of Group 1 gallbladder cancers were stage III and 38.1% were stage V. The 30-day postoperative mortality rate in Group 1 and Group 2 patients was 9.5% and 7.7%, respectively. The cumulative survival of Group 1 patients was not different from that of Group 2 patients (log-rank test, p>0.05). CONCLUSIONS: Age, the interval of symptoms prior to admission, the location of abdominal pain, fever, leukocytosis, and the absence of jaundice suggested the presence of acute cholecystitis in gallbladder carcinoma. A high index of suspicion of the disease, intraoperative examination of gallbladder specimens, and more aggressive surgical treatment may improve patient survival.  相似文献   
72.
OBJECTIVE: Few cases of verrucous carcinoma of the penis with foci of invasive squamous cell carcinoma have been reported and denominated "hybrid tumors". The accuracy of this term is discussed in this paper. METHODS/RESULTS: A huge penile mass in a patient that had undergone three previous operations for lesions diagnosed as verrucous carcinoma is reported. Partial penectomy was performed. Histological examination showed a very well-differentiated squamous cell carcinoma. PCR (polymerase chain reaction) did not detect any type of human papillomavirus (HPV) in the tumor. CONCLUSIONS: Verrucous carcinoma is a strictly-defined lesion with a different biological behaviour from that of squamous carcinoma. Preoperative deep biopsy may miss the squamous cell carcinoma. Definitive diagnosis can only be achieved by histological examination of the surgical specimen. In future, DNA studies could possibly support preoperative diagnosis of this lesion.  相似文献   
73.
PURPOSE: To review the current literature and generate recommendations on the role of newer technology in the management of the unanticipated difficult airway. METHODS: A literature search using key words and filters of English language and English abstracted publications from 1990-96 contained in the Medline, Current Contents and Biological Abstracts databases was carried out. The literature was reviewed and condensed and a series of evidence-based recommendations were evolved. CONCLUSIONS: The unanticipated difficult airway occurs with a low but consistent incidence in anaesthesia practice. Difficult direct laryngoscopy occurs in 1.5-8.5% of general anaesthetics and difficult intubation occurs with a similar incidence. Failed intubation occurs in 0.13-0.3% general anaesthetics. Current techniques for predicting difficulty with laryngoscopy and intubation are sensitive, non-specific and have a low positive predictive value. Assessment techniques which utilize multiple characteristics to derive a risk factor tend to be more accurate predictors. Devices such as the laryngeal mask, lighted stylet and rigid fibreoptic laryngoscopes, in the setting of unanticipated difficult airway, are effective in establishing a patient airway, may reduce morbidity and are occasionally lifesaving. Evidence supports their use in this setting as either alternatives to facemask and bag ventilation, when it is inadequate to support oxygenation, or to the direct laryngoscope, when tracheal intubation has failed. Specifically, the laryngeal mask and Combitube have proved to be effective in establishing and maintaining a patent airway in "cannot ventilate" situations. The lighted stylet and Bullard (rigid) fibreoptic scope are effective in many instances where the direct laryngoscope has failed to facilitate tracheal intubation. The data also support integration of these devices into strategies to manage difficult airway as the new standard of care. Training programmes should ensure graduate physicians are trained in the use of these alternatives. Continuing medical education courses should allow physicians in practice the opportunity to train with these alternative devices.  相似文献   
74.
OBJECTIVE: Low-grade fibrosarcomas and desmoid tumors present a surgical challenge in that they have a strong tendency for local invasion, surgical margins are poorly delineated, and complete resections are difficult. Nowhere is this more evident than in those lesions involving the brachial plexus. We review our experience with these difficult lesions. METHODS: From a prospective database of 2900 patients admitted for treatment of sarcoma between 1982 and 1996, we identified 15 patients with involvement of the brachial plexus by a low-grade fibrosarcoma or desmoid tumor. All patients underwent resection, with 13 of 15 receiving adjuvant radiotherapy. The 15 patients had a mean age at initial operation of 47 years. The male-to-female ratio was 8:7. The mean follow-up period was 65 months (median, 53 mo). RESULTS: Gross total resection was achieved in 12 patients (80%), although 11 of these patients had positive surgical margins. Overall, 64% of the tumors have recurred locally. There were no distant metastases, and no patients died as a result of their disease. One patient died as a result of unrelated cancer. An assessment of the functional outcomes revealed seven patients with normal function or mild neurological deficits and eight who were suffering from significant weakness, debilitation, or chronic pain. One patient required forequarter amputation. CONCLUSION: Surgical resection plus postoperative radiotherapy is the treatment of choice for low-grade fibrosarcomas and desmoid tumors involving the brachial plexus. However, aggressive surgical management with the goal of achieving a gross total resection with negative histological margins can produce unnecessary morbidity. Preserving function should be a primary goal of the operations, although this will be associated with residual disease and will risk local recurrence but rarely death resulting from the disease.  相似文献   
75.
The murine monoclonal antibody A7 (MAb A7) is reactive against most human gastric cancer cell lines. Using a nude mouse peritoneal dissemination model of human gastric cancer, we investigated targeted chemotherapy using a conjugate of neocarzinostatin (NCS) with MAb A7 (A7-NCS). After demonstrating cytotoxicity of the complex against the human gastric cancer cell line MKN45 in vitro, we intraperitoneally injected A7-NCS, NCS or saline into nude mice bearing peritoneally disseminated human gastric cancer. A7-NCS inhibited peritoneal dissemination significantly more effectively than NCS. MAb A7 may prove to be an effective carrier for antineoplastic drugs in patients with peritoneal dissemination of gastric cancer.  相似文献   
76.
The ability of recombinant preparations of equine herpesvirus type 1 (EHV-1) glycoprotein D (gD) to elicit specific antibody and T lymphocyte responses in the BALB/c mouse model of respiratory infection was investigated. Recombinant gD (rgD) expressed as a glutathione-S-transferase (GST) fusion protein in Escherichia coli elicited both high titer neutralizing antibody (nAb) and CD4 T cell proliferative responses following subcutaneous or intranasal immunization, but elicited only a weak antibody response after intraperitoneal immunization. Protection against respiratory tract infection with pathogenic EHV-1 RacL11 was observed in mice immunized subcutaneously with GST-gD. Furthermore, the degree of protection correlated to the titer of nAb and the T cell response observed. Finally, GST-gD was more effective in protecting against respiratory RacL11 infection if delivered intranasally. These results confirm that gD plays an important role in eliciting the protective immune response against EHV-1 infection, and indicate that subunit vaccines containing preparations of gD may be very effective if delivered directly to the upper respiratory tract.  相似文献   
77.
Myocardial texture analysis of two-dimensional echocardiographic gray level distribution is abnormal in hypertensive patients with severe increase of left ventricular mass. The aim of this study was to investigate the behavior of this parameter in hypertensive patients with absent-to-moderate left ventricular hypertrophy, more representative of the overall hypertensive population. We compared male essential hypertensive patients, with absent or mild-to-moderate left ventricular hypertrophy, with normotensive sedentary healthy subjects as controls. The groups (n = 18 each) were age- (+/- 2 years) and sex-matched. All subjects performed ambulatory blood pressure measurements for the evaluation of 24 h mean systolic and diastolic blood pressure. Quantitative analysis of echocardiographic digitized imaging was performed through a calibrated 256 gray level digitization system to calculate midseptum and midposterior end-diastolic and end-systolic first and second order textural analysis. In particular were observed the mean gray level cyclic variations to deriving the cyclic variation index (CVI). The hypertensives showed a significantly lower CVI compared with controls both for septum (P < .001) and for posterior wall (P < .0001). No significant relationships were found between CVI and relative diastolic thickness both of septum and posterior wall. Conversely, a significant inverse relationship was found between systolic arterial pressure values and CVI both of septum and posterior wall. Abnormalities of two dimensional echocardiographic gray level distribution are present also in hypertensive patients with absent or with mild-to-moderate levels of left ventricular hypertrophy, but seem unrelated to the degree of echocardiographic hypertrophy as such. Changes in collagen network distribution or microcirculatory alterations, secondary to pressure-volume overload per se or to other complex humoral factors, could explain these abnormalities. Further work is needed to establish the clinical, therapeutic, and prognostic implications of these findings.  相似文献   
78.
OBJECTIVE: To examine the effect of a clinical and administrative partnership with an academic urban Level I trauma center on the patient transfer practices at a suburban/rural Level II center. METHODS: Data for 2 years before affiliation (PRE) abstracted from inpatient charts and the trauma registry were compared with that for 2 years after (POST). The following data were collected: number of, reason for, and destination and demographics of transfers. Chi(2) test and t test analyses were used; p < 0.05 defined significance; data are mean +/- SEM. RESULTS: Transfer rate increased from 4% PRE to 6.9% (p = 0.001) POST with no significant difference in age, Glasgow Coma Scale score, Injury Severity Score, or Revised Trauma Score. Repatriation occurred in 12.8% POST (none PRE). The current Level I facility accepted 1.8% of all transfers PRE and 36.4% POST (p = 0.0001). PRE/POST rates by reason are as follows: pediatric, 14.6%/9.0% (p = 0.04); intensive care unit, 0.4%/1.7% (p = 0.13); complex orthopedic, 100%/0% (p = 0.005); vascular, 50%/0% (p = 0.008); spinal cord injury, 100%/100%; and ophthalmologic, 0%/100% (p = 0.005). CONCLUSIONS: In this experience of Level I/II partnership (1) transfer patterns were altered, (2) select patient cohort transfers decreased (pediatric, complex orthopedic, vascular), whereas others increased (aortic work-up), and (3) repatriation rates were low.  相似文献   
79.
Human immunodeficiency virus (HIV) seroprevalence rates among rural trauma patients range between 0.15 and 1.32 per cent. A random sample of trauma patients treated at our rural trauma center between September 1994 and November 1995 was enrolled into a blind HIV serosurvey. Five hundred sixty-six of 1315 trauma patients (43%) were tested. Two of the 566 patients (0.35%) were HIV positive. A review of aggregate data for HIV infection among rural trauma patients in the United States show that 28 of the 4639 patients (0.60%) are HIV positive. We conclude that there was a low HIV incidence among our trauma patients from September 1994 to November 1995, and the cost-effectiveness of HIV testing for rural trauma patients is questionable with incidences between 0.5 and 1.0 per cent.  相似文献   
80.
Three mitogen-activated protein kinase pathways are up-regulated during the activation of T lymphocytes, the extracellular signal-regulated kinase (ERK), Jun NH2-terminal kinase, and p38 mitogen-activated protein kinase pathways. To examine the effects of blocking the ERK pathway on T cell activation, we used the inhibitor U0126, which has been shown to specifically block mitogen-activated protein kinase/ERK kinase (MEK), the kinase upstream of ERK. This compound inhibited T cell proliferation in response to antigenic stimulation or cross-linked anti-CD3 plus anti-CD28 Abs, but had no effect on IL-2-induced proliferation. The block in T cell proliferation was mediated by down-regulating IL-2 mRNA levels. Blocking Ag-induced proliferation by inhibiting MEK did not induce anergy, unlike treatments that block entry into the cell cycle following antigenic stimulation. Surprisingly, induction of anergy in T cells exposed to TCR cross-linking in the absence of costimulation was also not affected by blocking MEK, unlike cyclosporin A treatment that blocks anergy induction. These results suggest that inhibition of MEK prevents T cell proliferation in the short term, but does not cause any long-term effects on either T cell activation or induction of anergy. These findings may help determine the viability of using mitogen-activated protein kinase inhibitors as immune suppressants.  相似文献   
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