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981.
In a recent study, we showed that the rat slow soleus and fast plantaris muscles exhibited different time courses for the response of specific heat shock proteins (HSPs) after 1 h of heat stress. We hypothesized that these differential responses were related, in part, to the varying fiber type composition of these muscles. To further test this hypothesis, we now have determined the responses of Hsp60, Hsp72, and Hsc73 during the 60 h following exposure to a single bout of heat stress in the deep (relatively high percentage of slow fibers) and superficial regions (only fast fibers) of the adult rat gastrocnemius muscle. The temperature of the musculature in the left hindlimb was elevated to approximately 42 degrees C for 1 h, while the right hindlimb served as a control. Two hours after the heat stress, the Hsp60 levels were increased by 1.3- and 2.0-fold in the deep and superficial regions, respectively. The Hsp72 levels were increased (1.8-fold) in the deep region at 8 h after heat stress, whereas in the superficial region these levels were increased between 4 and 48 h (peak at 36 h by 10-fold) after the heat stress. No changes were observed for Hsc73 in either region of the muscle. Combined with our previous data, the results indicate that the responses of HSPs in the rat hindlimb muscles after a single exposure to heat stress are related to fiber type composition of the muscle or muscle region or to the inherent properties of each HSP. From a clinical viewpoint, these data indicate that specific regions (most likely based on fiber type composition) within a muscle may be affected differentially by any intervention inducing HSPs.  相似文献   
982.
Spleen hemostasis using high-intensity ultrasound: survival and healing   总被引:6,自引:0,他引:6  
BACKGROUND: Previous studies have shown that high-intensity focused ultrasound (HIFU) can effectively control bleeding of incised livers and spleens and punctured vessels. This current study investigated the long-term safety of HIFU in splenic hemostasis. METHODS: A total of 21 rabbits were randomly assigned to two groups: HIFU treatment (n = 14), and sham treatment (n = 7). All animals underwent sterile laparotomy and splenic exposure. The HIFU-treated animals received splenic incisions, 8 to 10 mm long and 4 to 5 mm deep, and immediate 9.6-MHz HIFU until hemostasis was achieved. After recovery, ultrasound images, blood samples, and histologic samples were collected on days 0, 1, 3, 7, 14, 28, and 60. RESULTS: All 14 splenic injuries were hemostatic after an average of 96 seconds of HIFU application. There was evidence of rebleeding in one animal between days 3 and 7 posttreatment. Subsequent blood analysis showed no significant difference in serial hematologic or coagulation measures between HIFU and sham groups. Histologic examination up to 60 days posttreatment revealed scarring and spleen tissue regeneration at the treatment site. CONCLUSION: HIFU provides an effective and safe method of achieving hemostasis after acute splenic injury.  相似文献   
983.
BACKGROUND: Factors thought to influence the decision for limb salvage include injury severity, physiologic reserve of the patient, and characteristics of the patient and their support system. METHODS: Eligible patients were between the ages of 16 and 69 with Gustilo type IIIB and IIIC tibial fractures, dysvascular limbs resulting from trauma, type IIIB ankle fractures, or severe open midfoot or hindfoot injuries. Data collected at enrollment relevant to the decision-making process included injury characteristics and its treatment, and the nature and severity of other injuries. Logistic regression and stepwise modeling were used to determine the effect of each covariate on the variable salvage/ amputation. RESULTS: Of 527 patients included in the analysis, 408 left the hospital with a salvaged limb. Of the 119 amputations performed, 55 were immediate and 64 were delayed. The multivariate analysis confirmed the bivariate analysis: all injury characteristics remained significant predictors of limb status with the exception of bone loss; and soft tissue injury and absence of plantar sensation were the most important factors in accounting for model validity. CONCLUSION: Soft tissue injury severity has the greatest impact on decision making regarding limb salvage versus amputation.  相似文献   
984.
Buell JF  Husted T  Hanaway MJ  Peddi VR  Trofe J  Gross TG  Beebe TM  First MR  Woodle ES 《Surgery》2002,132(4):754-8; discussion 758-60
BACKGROUND: Gastric cancer in the United States is often diagnosed at advanced stages, resulting in dismal outcomes. In the immunosuppressed transplant recipient population, little is known about the clinical staging and outcome of these compromised patients. METHODS: All US cases reported to the Israel Penn International Transplant Tumor Registry were retrospectively examined for patient demographics, immunosuppressive therapy, tumor characteristics, therapeutic modalities, and mortality. Statistical analysis was performed with Students t test, chi-square analysis, and log-rank analysis by the method of Kaplan-Meier. RESULTS: Gastric cancer was identified in 34 recipients: 28 (82%) were male; 24 (71%) were white. Mean age at diagnosis was 58 +/- 11 years. Twenty-four (71%) patients received kidney transplants, 7 (21%) received heart transplants, and 3 (9%) received liver transplants. Fifty percent received induction therapy, whereas 94% were maintained on calcineurin inhibitors and corticosteroids. Thirty-five percent of patients were diagnosed during evaluation for gastrointestinal symptoms, with the remaining cases discovered incidentally during endoscopy (53%) or during computed tomography (12%) performed for other reasons. Stage varied at presentation as follows: stage I (n = 6), stage II (n = 11), stage III (n = 13), and stage IV (n = 4). Incidental diagnoses resulted in a lower stage malignancy (P <.001) and greater 1-year and 5-year survivals (P <.05) compared with those patients whose were diagnosed after being evaluated of gastrointestinal symptoms. CONCLUSION: In the United States, because gastric cancer in the transplant recipient is frequently identified at an earlier stage (50% were stages I and II) than in the general population, survivals are equivalent despite continued administration of immunosuppression. This early identification may be attributed to more frequent presymptom diagnosis and staging, resulting from incidental detection of these malignancies during posttransplant upper endoscopy or computed tomography. Early detection has resulted in a 29% 5-year survival for the entire transplant recipient group compared with a 5% to 15% 5-year survival in the general population.  相似文献   
985.
986.
987.
OBJECTIVE: To evaluate an integrated fellowship in vascular surgery and interventional radiology initiated to train vascular surgeons in endovascular techniques and to train radiology fellows in clinical aspects of vascular diseases. SUMMARY BACKGROUND DATA: The rapid evolution of endovascular techniques for the treatment of vascular diseases requires that vascular surgeons develop proficiency in these techniques and that interventional radiologists develop proficiency in the clinical evaluation and management of patients who are best treated with endovascular techniques. In response to this need the authors initiated an integrated fellowship in vascular surgery and interventional radiology and now report their interim results. METHODS: Since 1999 vascular fellows and radiology fellows performed an identical year-long fellowship in interventional radiology. During the fellowship, vascular surgery and radiology fellows perform both vascular and nonvascular interventional procedures. Both vascular surgery and radiology-based fellows spend one quarter of the year on the vascular service performing endovascular aortic aneurysm repairs and acquiring clinical experience in the vascular surgery inpatient and outpatient services. Vascular surgery fellows then complete an additional year-long fellowship in vascular surgery. To evaluate the type and number of interventional radiology procedures, the authors analyzed records of cases performed by all interventional radiology and vascular surgery fellows from a prospectively maintained database. The attitudes of vascular surgery and interventional radiology faculty and fellows toward the integrated fellowship were surveyed using a formal questionnaire. RESULTS: During the fellowship each fellow performed an average of 1,201 procedures, including 808 vascular procedures (236 diagnostic angiograms, 70 arterial interventions, 59 diagnostic venograms, 475 venous interventions, and 43 hemodialysis graft interventions) and 393 nonvascular procedures. On average fellows performed 20 endovascular aortic aneurysm repairs per year. There was no significant difference between the vascular surgery and radiology fellows in either the spectrum or number of cases performed. Eighty-eight percent (23/26) of the questionnaires were completed and returned. Both interventional radiologists and vascular surgeons strongly supported the integrated fellowship model and favored continuation of the integrated program. Vascular surgery and interventional radiology faculty members wanted additional training in clinical vascular surgery for the radiology-based fellows. With the exception of the radiology fellows there was uniform agreement that vascular surgery fellows benefit from training in nonvascular aspects of interventional radiology. CONCLUSIONS: Integration of vascular surgery and interventional radiology fellowships is feasible and is mutually beneficial to both disciplines. Furthermore, the integrated fellowship provides exceptional training for vascular surgery and interventional radiology fellows in all catheter-based techniques that far exceeds the minimum requirements for credentialing suggested by various professional societies. There is a clear need for cooperation and active involvement on the parts of the American Board of Radiology and the American Board of Surgery and its Vascular Board to create hybrid training programs that meet mutually agreed-on criteria that document sufficient acquisition of both the cognitive and technical skills required to manage patients undergoing endovascular procedures safely and effectively.  相似文献   
988.
989.
This study was carried out to evaluate the relationship between body iron status and lipid profile in hospital admitted clinically diagnosed AMI patients considering the concept that there is a potential association between body iron status and coronary heart disease (CHD). Total 80 subjects were selected, of which 40 were healthy adults and 40 were AMI patients. Fasting blood samples were collected from healthy adults. Blood samples of AMI patients were collected within 24 hours of the attack of myocardial infarction. Body iron status was measured in term of 3 variables serum total iron concentration, TIBC and transferrin saturation. Lipid profile variables measure were total cholesterol, triglyceride, LDL-cholesterol and HDL-cholesterol. No correlation was found between serum iron and the variables of lipid profile. TIBC was found to maintain negative correlation with total cholesterol, triglyceride and LDL-cholesterol but positive correlation with HDL-cholesterol. Transferrin saturation was found to maintain strongly positive correlation with total cholesterol, triglyceride and LDL-cholesterol but strongly negative correlation with HDL-cholesterol. This correlation of TIBC and transferrin saturation with lipid profile supports the hypothesis that there is a potential association between body iron status and coronary heart disease.  相似文献   
990.
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