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51.
Steven G. E. Marsh Ekkehard D. Albert Walter F. Bodmer Ronald E. Bontrop Bo Dupont Henry A. Erlich Daniel E. Geraghty John A. Hansen Bernard Mach Wolfgang R. Mayr Peter Parham Effie W. Petersdorf Takehiko Sasazuki Geziena M. Th. Schreuder Jack L. Strominger Arne Svejgaard Paul I. Terasaki 《International journal of immunogenetics》2002,29(6):463-515
52.
A bstract Isolated mitral valve replacement using the CarboMedics prosthetic mitral valve (CarboMedics, Inc., Austin, TX) was studied in 13 centers in the United States, Canada, and Scandinavia between 1987 and 1993 in 428 patients with a mean age of 57 ± 14 years. Actuarial survivals at 1, 2, and 5 years were 88.2% and 75.8%. Freedom from events at 5 years were 94.8% for major thromboembolism, 96.6% for thrombosis, and 96.7% for endocarditis. Linearized morbidity rates (events per 100 patient years) for events at > 30 days postoperatively were .51 thrombosis, 1.1 major thromboembolism, and .37 endocarditis. These results at early to mid-term compare favorably with the first generation bileaflet valve. 相似文献
53.
Jack Yamuy John K. Engelhardt Francisco R. Morales Michael H. Chase 《Brain research》1992,570(1-2):300-306
The objective of this study was to determine whether the aging process influences the changes in the electrophysiological properties of motoneurons that occur as a consequence of axotomy. Accordingly, using intracellular recording and stimulating techniques, the basic electrical properties of control (unaxotomized) and axotomized spinal cord motoneurons of aged cats were determined. Compared with control motoneurons, axotomized motoneurons exhibited increases in input resistance (Rin), membrane time constant (τb) and the equalizing time constant (τc). While the electrotonic length (L) remained unchanged, axotomy induced a decrease in the total cell capacitance (Ccell. The post-axotomy reduction of Ccell indicates that the motoneuron surface area was reduced and the increased membrane time constant indicates that there was an increase in membrane resistivity (Rm). The post-axotomy conservation of L accompanied by an increase in Rm suggests that aged axotomized motoneurons undergo geometrical changes. Furthermore, calculations based on cable theory suggest that the diameter of the equivalent cylinder (d) decreased following axotomy, whereas the equivalent cylinder length (l) remained unaffected. It is concluded that axotomy produces significant alterations in the soma-dendritic portion of aged spinal motoneurons, as indicated by the changes found in their passive electrophysiological properties, and that the pattern of the response that occurs in axotomized motoneurons of adult cats is also present in axotomized motoneurons of aged animals. 相似文献
54.
Dr. Schlomo Schneebaum MD Joseph Papo MD Moshe Graif MD Mimi Baratz MD Jack Baron MS Yehuda Skornik MD 《Annals of surgical oncology》1997,4(5):371-376
Background: Despite new adjuvant therapy, 50% of patients with colon cancer will have recurrent disease. This study investigated the
use of a radiolabeled monoclonal antibody in locating occult tumor during surgery for recurrent colorectal cancer.
Methods: Twenty-two patients with recurrent colorectal cancer underwent surgery using the radioimmunoguided surgery (RIGS) system.
All patients were subjected to abdominal and chest computed tomography (CT). Before surgery, patients were injected with the
CC49 monoclonal antibody (MoAb), anti-TAG antibody labeled with125I. Ten patients with elevated carcinoembryonic antigen (CEA) levels and no CT findings had a scintigraphy scan with an anti-CEA
MoAb labeled with99Tc. Human antimouse antibody levels of these patients were within normal limits. Surgical exploration including liver ultrasound
examination was followed by survey with a gamma-detecting probe (GDP).
Results: There was MoAb tumor localization in 100% of the patients. CT found nine tumor sites, traditional surgical exploration 30,
and the GDP 51, with 44 confirmed by pathology (hematoxylin and eosin). The RIGS system found occult tumor in 10 patients
(45.4%) and resulted in major changes in surgical procedure in 11 patients. In the 10 patients who had scintigraphy scans,
10 tumor sites were identified, whereas RIGS found an additional eight sites.
Conclusion: RIGS technology offers a substantial benefit for patients undergoing surgery for recurrent colorectal cancer and a better
chance of finding recurrent tumor intraoperatively in patients who have elevated CEA levels with no other CT findings.
Presented at the Annual Cancer Symposium of The Society of Surgical Oncology, Atlanta, Georgia, March 21–24, 1996. 相似文献
55.
56.
Louise Nadon Jack Siemiatycki Ron Dewar Daniel Krewski Michel Grin 《American journal of industrial medicine》1995,28(3):303-324
Polycyclic aromatic hydrocarbons (PAHs) demonstrate carcinogenic activity in animal models. Although some epidemiologic studies have implicated PAHs as risk factors for human cancer, the evidence reported to date has not been consistent. The purpose of this report is to describe the associations between occupational exposure to PAHs in the workplace and each of 14 types of cancer. A population-based, case-control study was carried out in Montreal to investigate associations between a large variety of environmental and occupational exposures on the one hand, and several types of cancer on the other. A detailed job history was obtained from each subject along with information on a number of potential confounders. Each job history was reviewed by a team of experts, who used this information to construct a corresponding history of occupational exposures. Among the PAH exposures considered were benzo(a)pyrene (B(a)P) and five categories of PAHs defined on the basis of the source material, namely, wood, petroleum, coal, other sources, and any source. Altogether, 3,730 cancer patients and 533 population controls were interviewed and their job exposure histories coded. For each of 14 types of cancer analyzed, three control groups were available: other cancer patients, population controls, and the pooled set of cancer and population controls. The associations between 14 cancer types and 6 PAH exposures were analyzed using logistic regression methods. For most types of cancer evaluated, there was no evidence of excess risk due to PAHs at the levels encountered in the occupations in which PAH exposure has been prevalent in the Montreal area. For a few cancer sites–the esophagus, the pancreas, and the prostate gland–there were suggestions of excess risk; these observations are noteworthy hypotheses for further investigation. For lung cancer, there appeared to be an increased risk due to PAHs among nonsmokers and light smokers, but not among heavy smokers. 相似文献
57.
58.
Laparoscopic Cholecystectomy for Acute Cholecystitis: Prospective Trial 总被引:23,自引:0,他引:23
Samuel Eldar Edmond Sabo Ernest Nash Jack Abrahamson Ibrahim Matter 《World journal of surgery》1997,21(5):540-545
p
< 0.00001) and for hydrops (28.5%) and empyema of the gallbladder
(28.5%) (
p
= 0.004). The difference in conversion
between the group with acute necrotizing (gangrenous) cholecystitis and
the two groups with hydrops and empyema of the gallbladder was not
statistically significant (
p
= 0.07). The complication
rates of acute cholecystitis, hydrops, empyema of the gallbladder, and
gangrenous cholecystitis were 9.0%, 9.5%, 14.0%, and 20.0%,
respectively (
p
= NS). Patients with an operative
delay of 96 hours or less from the onset of acute cholecystitis had a
conversion rate of 23%, whereas a delay of more than 96 hours was
associated with a conversion rate of 47% (
p
= 0.022).
The complication rate was 8.5% in the laparoscopic group and 27% in
the converted group (
p
= 0.013). Patients over 65
years of age, with a history of biliary disease, a nonpalpable
gallbladder, WBC count over 13,000/cc, and acute gangrenous
cholecystitis were independently associated with a high LC conversion
rate; male patients, finding large bile stones, serum bilirubin over
0.8 mg/dl, and WBC count over 13,000/cc were independently associated
with a high complication rate following laparoscopic surgery with or
without conversion. Generally, LC can be performed safely for acute
cholecystitis, with acceptably low conversion and complication rates.
Different forms of cholecystitis carry various conversion and
complication rates in selected cases. LC for acute cholecystitis should
be performed within 96 hours of the onset of disease. Predictors of
conversion and complications may be helpful when planning the
laparoscopic approach to acute cholecystitis. 相似文献
59.
Effects of race and socioeconomic status on survival of 1,332 black, hispanic, and white women with breast cancer 总被引:3,自引:0,他引:3
Dr. Luisa Franzini PhD Anna Fay Williams PhD Jack Franklin PhD S. Eva Singletary MD Richard L. Theriault DO 《Annals of surgical oncology》1997,4(2):111-118
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
60.
Corinna S. Bowser Jean Kaye Rauno O. Joks Cascy-Arnoux Charlot H. Jack Moallem 《Pediatric allergy and immunology》2007,18(4):298-303
Elevated serum immunoglobulin E (IgE) and increased prevalence of atopy is reported in patients infected with human immunodeficiency virus (HIV). The elevated serum IgE may be attributed to polyclonal stimulation of B cells or IgE production against allergens, viruses, fungi and bacteria. This study investigates the prevalence of atopy in perinatally HIV-infected children, and the relationships between serum IgE (and other serum immunoglobulins) with atopy, CD4+ cell count and HIV-disease stage. Serum immunoglobulin levels, epicutaneous skin test for common aeroallergens, clinical Centers for Disease Control and Prevention (CDC) classification, CD4+ cell counts and allergy history were extracted from the charts of perinatally HIV-infected children on highly active antiretroviral therapy. The prevalence of atopy (52%) and the pattern of aeroallergen sensitivity were comparable with the US pediatric population. Serum IgE levels did not correlate with clinical disease stage. However, in non-atopic patients, serum IgE levels increased with disease progression (p = 0.02). There was an inverse relationship between the prevalence of elevated serum IgE levels and atopy with progression of disease (p = 0.019). Serum IgE did not correlate with atopy, CD4+ cell count, or duration of HIV infection or levels of serum immunoglobulins. This is the first study to show no increased prevalence of atopy in perinatally HIV-infected children compared with the general population. In advanced stages of HIV, elevated serum IgE may be specific for antigens other than those known as allergens. 相似文献