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21.
Apoptosis is critical for organ development, tissue homeostasis, the elimination of abnormal cells and the maintenance of immune homeostasis by variable regulatory mechanisms. The death of T lymphocytes following their activation involves a series of proteases (caspases), which comprise the central executioners of apoptosis. Abnormal regulation of apoptosis results in disease. T-cell resistance against apoptosis contributes to inappropriate T-cell accumulation and the perpetuation of the chronic inflammatory process in inflammatory bowel disease with potential tumourigenic effect. The use of antitumour necrosis factor-alpha, anti-interleukin-6R and anti-interleukin-12 antibodies suppresses colitis activity by induction of T-cell apoptosis, thereby having important implications for the design of effective therapeutic strategies in inflammatory bowel diseases. Contrary to international data, the incidence of cancer in Greek patients with inflammatory bowel disease appears to be low. A balance between cell proliferation (Ki-67 overexpression) and apoptosis (Bax protein overexpression) may partly explain the low incidence of cancer development in Greek inflammatory bowel disease patients.  相似文献   
22.
This paper describes the administrative organisation of veterinary public health (VPH) activities in seven countries of the Western Mediterranean region. These structures vary greatly, as a function of the national administrations overall and, in particular, as a result of assigning VPH to either the Ministry of Agriculture or Public Health. Whereas the VPH unit is generally involved in specific veterinary food hygiene activities, the control of zoonotic diseases is most often assigned to the Veterinary Services. In most countries of the region, VPH is still approached as too narrow a discipline, and the importance of VPH activities is often not recognised by decision-makers at the highest governmental levels.  相似文献   
23.
Purpose. The effect of retrograde cerebral perfusion on the incidence of stroke and death among patients undergoing repair of aneurysms of the ascending aorta and transverse arch was determined.

Material and Methods. Between January 1991 and March 1995, 161 patients were operated on for aneurysms of the ascending aorta and transverse arch. Thirty-three of the patients (20%) had an aneurysm of the ascending aorta only and 128 (80%) had aneurysms of both the ascending aorta and the transverse arch. All the patients underwent cardiopulmonary bypass, profound hypothermia, and circulatory arrest, and 120 (74%) also underwent retrograde cerebral perfusion. Median pump time was 143 minutes (range, 21 to 461 minutes). Median circulatory arrest time was 42 minutes (range, 8 to 111 minutes), and median myocardial ischemic time was 71 minutes (range, 14 to 306 minutes).

Results. The overall 30-day mortality rate was 6% (9 patients) and the incidence of stroke was 4% (7 patients). The use of retrograde cerebral perfusion demonstrated a protective effect against stroke (3 of 120 patients, or 3%) compared with no retrograde cerebral perfusion (4 of 41 patients, or 9%; odds ratio, 0.24; confidence interval, 0.06 to 0.99; p < 0.049). This was most significant in patients more than 70 years of age; none of the 36 elderly patients who received retrograde cerebral perfusion had a stroke, compared with 3 of the 13 (23%) who did not (p < 0.003). Only pump time was associated with an increased risk of stroke (odds ratio, 1.01; 95% confidence interval, 1.00 to 1.02; p < 0.005). Pump time also was associated with increased mortality (odds ratio, 1.01; 95% confidence interval, 1.00 to 1.02; p < 0.008).

Conclusion. Retrograde cerebral perfusion decreased the incidence of stroke in patients undergoing repair of aneurysms of the ascending aorta and transverse arch.  相似文献   

24.
BACKGROUND: Transforming growth factor-beta(1) (TGF-beta(1)) is the major fibrogenic growth factor implicated in the pathogenesis of renal scarring. Proteinuria is a poor prognostic feature for various types of glomerular disease and its toxic action may be related to the activation of tubular epithelial cells towards increased production of cytokines and chemoattractant peptides. In this work we studied the site of synthesis and expression profile of TGF-beta(1) in the renal tissue of patients with heavy proteinuria and examined the relation of this expression with the urinary excretion of TGF-beta(1). METHODS: Twenty-five patients with heavy proteinuria (8.4+/-3.0 g/24 h) were included in the study. All patients underwent a diagnostic kidney biopsy and were commenced on immunosuppressive therapy with corticosteroids and cyclosporin. The sites of synthesis and expression profile of TGF-beta(1) mRNA and protein in the kidney were examined by in situ hybridization and immunohistochemistry. Urinary and plasma TGF-beta(1) levels were determined by ELISA before the initiation of treatment and 6 months later and compared with those of normal subjects and of patients with IgA nephropathy and normal urinary protein excretion. RESULTS: The site of synthesis and expression of TGF-beta(1) in the renal tissue of patients with heavy proteinuria was mainly localized within the cytoplasm of tubular epithelial cells. Interstitial expression was also present but glomerular TGF-beta(1) expression was found only in patients with mesangial proliferation. Urinary TGF-beta(1) excretion was significantly higher in nephrotic patients compared with normal subjects and with patients with IgA nephropathy and normal urinary protein excretion (783+/-280 vs 310+/-140 and 375+/-90 ng/24 h, respectively; P<0.01). In patients with remission of proteinuria after immunosuppressive therapy, urinary TGF-beta(1) excretion was significantly reduced (from 749+/-290 to 495+/-130 ng/24 h; P<0.01), while in patients with persistent nephrotic syndrome, it remained elevated. CONCLUSIONS: The localization of TGF-beta(1) mRNA and protein within tubular epithelial cells, along with its increased urinary excretion in patients with nephrotic syndrome, suggest the activation of these cells by filtered protein towards increased TGF-beta(1) production.  相似文献   
25.
We describe the case of a recipient of an implantable cardioverter defibrillator with multiple syncopal episodes due both to superior vena cava obstruction and electrical instability. These complications occurred in the presence of two transvenous implantable cardioverter defibrillator leads. The patient has been managed conservatively with anticoagulants and new antiarrhythmic drugs with improvement in both his clinical problems.  相似文献   
26.
BACKGROUND: Epidermoid splenic cysts are uncommon lesions of the spleen. They are known to become symptomatic as a consequence of enlargement, infection, or rupture, the latter being an exceedingly rare complication traditionally treated with open splenectomy. We herein report a unique case of a giant epidermoid splenic cyst that ruptured spontaneously and was successfully treated with the laparoscopic approach. CONCLUSION: Laparoscopic surgery may be considered an initial treatment option in cases of very large epidermoid cysts even when rupture occurs.  相似文献   
27.
This work describes the design and construction of a device that facilitates the loading of DNA samples onto polyacrylamide gels for detection in the Perkin Elmer/Applied Biosystems (PE/ABI) 373 and 377 DNA sequencing instruments. The device is mounted onto the existing gel cassettes and makes the process of loading high-density gels less cumbersome while the associated time and errors are reduced. The principle of operation includes the simultaneous transfer of the entire batch of samples, in which a spring-loaded air cylinder generates positive pressure and flexible silica capillaries transfer the samples. A retractable capillary array carrier allows the delivery ends of the capillaries to be held up clear of the gel during loader attachment on the gel plates, while enabling their insertion in the gel wells once the device is securely mounted. Gel-loading devices capable of simultaneously transferring 72 samples onto the PE/ABI 373 and 377 are currently being used in our production sequencing groups while a 96-sample transfer prototype undergoes testing.  相似文献   
28.
The specialty which has benefited the most from the rapid development of reconstructive microsurgery over the last decade, has been plastic surgery. In particular, the authors refer to reconstructive microsurgery after malignant tumor resection. Resections which used to cause serious psychological problems or which required multiple reconstructive procedures, can now be performed as a single stage procedure with good oncological, functional and aesthetic results. This experience concerns the treatment of 14 primary or recurrent malignant tumors of the skin and soft tissues using microsurgical techniques. The free latissimus dorsi musculocutaneous flap was the flap most commonly used. The authors also used the groin flap, the scapular flap, the tensor fasciae latae flap, the dorsalis pedis flap and finally the jejunum combined with the second metatarsus to reconstruct the mandible and the floor of the mouth. Complications consisted of complete necrosis of a dorsalis pedis flap and two revisions were performed for venous thrombosis. With a minimum follow-up of 5 years, one patient has developed a local recurrence and another has developed regional lymph node metastases. The functional and aesthetic results were quite satisfactory. The authors believe that microsurgery is a very valuable technique to treat difficult reconstructive problems.  相似文献   
29.
The aim of this study was to evaluate the medium term effects of the selective alpha1-adrenenergic- blocker terazocin on atrial natriuretic peptide (ANP) levels in patients with moderate essential hypertension. The drug was given orally for 30 days. The daily dose was 1 mg for the first 7 days, 2 mg for the next 7 days and 5 mg for the remaining period of this clinical trial. At the end of this clinical trial, plasma ANP levels increased by 16.40% despite the drop in blood pressure while left atrial and ventricular diameters remained unchanged. These findings indicate that the increase of ANP plasma levels is not the result of a mechanical load on the left cardiac chambers but the result of a pharmacological action. These observations also indicate that terazocin exerts part of its antihypertensive action by increasing ANP plasma levels.  相似文献   
30.
OBJECTIVE: To investigate the increased incidence of papillary thyroid cancer as found in specimens of total thyroidectomies and potential correlation with etiological factors. STUDY DESIGN AND SETTING: A retrospective study on patients who underwent total thyroidectomy, from 1990 to 2004, in an academic tertiary referral medical center. Patients' records were placed in a database, which included medical condition, history, and demographics. Histopathological slides were reviewed with special focus on papillary cancer. RESULTS: Our series consisted of 2379 patients. Thyroid cancer was confirmed in 354 patients (14.88%). Papillary carcinoma represented the most frequent type (316 patients, 89.26%). Increased incidence of papillary carcinomas was noticed after 1995, reaching the maximum value in the year 2000. After 2000, there was a descending trend and then a plateau. CONCLUSION: The increased incidence of papillary thyroid cannot be attributed to dietary patterns or increased diagnostic and therapeutic activity. It is likely to be associated with increased radiation and may be associated with the Chernobyl fallout.  相似文献   
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