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The T cell receptor (TCR) V beta repertoire in peripheral blood lymphocytes (PBL) of a large number of healthy individuals was analysed by quantifying V beta-specific mRNA using the method of anchored multiprimer DNA amplification and a reverse dot blot assay. Among 16 V beta gene families examined, particular V beta genes were noted to be unequally expressed in the PBL of 70 healthy donors. The frequently used genes belong to the V beta 4, 5, 6, 8 and 13 (12) families, while V beta 1, 9 and 15 were the least frequently used gene families. This bias in gene usage was observed in all individuals. Marked deviation from the mean percentage usage was noted for some V beta genes in individuals when their PBL were examined serially, but the common pattern of biased usage was not grossly distorted. When the TCR repertoire of different ethnic groups was examined, a lower mean frequency of V beta 3.2 was seen in the repertoire of 19 Caucasians compared with 25 age-matched Samoans (P < 0.003). Conversely, the expression of V beta 5.1 and V beta 5.3 was higher in Caucasians than in 51 age-matched Polynesians (Maoris and Samoans, P < 0.003). Considering the 20% co-efficient of variation in the estimate of V beta gene usage, our data from 70 unrelated individuals suggest that in PBL, individual variations in the TCR repertoire were superimposed upon a common biased usage of V beta genes in the general population.  相似文献   
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To evaluate influences on blood volume distribution, atrial natriuretic peptide concentrations (ANP) and thoracic and leg electrical impedance at 2.5 (TI2.5 and LI2.5, respectively) and 100 kHz (TI100 and LI100, respectively) were monitored during administration of ketanserin, noradrenaline and trimetaphan combined with lower body negative pressure (LBNP) in 12 subjects. Administration of clinically relevant doses of ketanserin alone did not induce changes in mean arterial pressure (MAP) or in the central blood volume, as electrical impedance and ANP concentrations did not change. During continued infusion of ketanserin an increase in MAP from a mean of 90 (range 83–108) to 113 (range 98–138) mmHg was induced by noradrenaline, but TI2.5 [mean 45.6 (range 39.3–54.2)] and TI100 [mean 33.8 (range 27.5–38.5) ] remainded stable until ganglionic blockade and LBNP were applied, when they increased by a mean of 3.1 (range 2.0–6.1) and 2.7 (range 1.1–4.2) , respectively (P < 0.05). Conversely, LI2.5 [mean 79.6 (range 74.1–89.4)] and LI100 [mean 56.7 (range 52.4–63.3) ] decreased by a mean of 3.2 (range 1.2–8.0) and 2.3 (range 0.9–3.9) ANP from a mean of 27.7 (range 10.2–62.7) to 12.7 (range 7.1–27.5) pmol· 1–1 and MAP fell to a mean of 62 (range 42–70) mmHg (P < 0.05). The heart rate was a mean of 75 (range 69–77) beats -min-' and did not change until LBNP, when it increased to a mean of 102 (range 78–104) beats · min–1, as presyncopal symptoms appeared. The data indicated that serotonergic blockade by ketanserin and -sympathetic stimulation by noradrenaline did not affect blood volume distribution in normal humans, but that ganglionic blockade combined with LBNP reduced the central blood volume as leg volume increased; during central hypovolaemia tachycardia induced by ganglionic blockade did not prevent the fall in MAP, and thereby the appearance of presyncopal symptoms.  相似文献   
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In this survey we investigated a population of small mammals in Eastern Croatia in order to determine Leptospira carriage rates and identify circulating serovars. Out of 67 trapped animals, 20 (29.9%) isolates were obtained. Identification of isolates using microscopic agglutination test, pulsed field gel electrophoresis and multi locus sequence typing revealed that 10 (50.0%) isolates belong to serogroup Pomona, serovar Mozdok, 6 (30.0%) isolates to serogroup Australis, serovar Jalna, 2 (10.0%) isolates to serogroup Sejroe, serovar Saxkoebing, and 1 (5.0%) isolate to serogroup Grippotyphosa, serovar Grippotyphosa. One isolate from serogroup Bataviae was unable to be identified to the serovar level. Amplification of a 331-bp region of the locus LA0322 using real-time polymerase chain reaction determined that 12 (60.0%) isolates belong to L. kirschneri, 6 (30.0%) isolates to L. interrogans, and 2 (10.0%) isolates to L. borgpetersenii. Leptospira carriage rate was high (29.9%), which corresponds to a high incidence of human and domestic animal leptospirosis in Eastern Croatia. Furthermore, 90.0% of the isolates belong to serogroups Pomona, Australis and Sejroe which are also the most prevalent serogroups in humans in this area. These findings suggest that small mammals might be an important source of Leptospira spp. infection in Eastern Croatia.  相似文献   
5.
Technique and survival after laparoscopically assisted right hemicolectomy   总被引:3,自引:0,他引:3  
Background The role of laparoscopic colon resection in the management of colon cancer is still controversial. In this article, the surgical strategy and techniques are described, with further consideration of the oncologically relevant aspects.Methods Between March 1993 and July 2003, we performed laparoscopic right hemicolectomy in 56 patients with right colon carcinoma. Average age was 74.5 years (range, 17–92). We performed a standardized surgical procedure that included mobilization from the vascularized mesenteric bridges with a window technique, transection of the ileocolic lymphovascular pedicle, and lateral and proximal mobilization of the ileocecum, ascending colon, right flexure, and proximale transversum. After enlargement of one of the trocar incisions the exteriorized colon was resected and an extracorporeal anastomosis was performed in the standard manner.Results There were no conversions to open. The mean operating time was 119 ± 38 min, the mean length of resected colon was 27.8 ± 4.48 cm, and the average width of the clear margins was 6.8 ± 5.3 cm. One patient died. Lymph nodes were positive in 21 patients. The 5-year survival rate in the 48 patients who were operated on with curative intent was 75%. We have had two local recurrences. The overall 5-year mortality-free fraction was 63%. Cox multivariate analysis showed that the mortality-prognostic factors were tumor stage and length of resected colon, whereas Kaplan-Meier analysis showed that the mortality-prognostic factors were positive lymph nodes and tumor stage.Conclusions Our results show that laparoscopic right hemicolectomy for colon cancer can be performed safely. Complications and recurrence rates are comparable to those for left-sided laparoscopic and open procedures. Therefore, we recommend this procedure as the method of choice. Laparoscopically treated patients with stage II and stage III disease have almost the same cumulative rate of survival.  相似文献   
6.
BACKGROUND/AIMS: The aim of the present study was to assess the severity of respiratory disturbances occurring after abdominal surgery and to identify surgical incisions that entail the least respiratory complications and postoperative pain. METHODOLOGY: A total of 105 patients divided into two groups were included in this randomized clinical trial. Seventy-five patients in the first group underwent upper abdominal surgery, and were operated on by use of vertical, oblique, transverse and elliptic incision. The remaining 30 patients in the second group were submitted to low abdominal surgery by use of vertical and oblique incision. Arterial blood gases and pulmonary shunt development were determined at 12 h preoperatively, and at 6 h, 72 h and 144 h postoperatively. During the postoperative course, VAS-pain score and use of tramadol were observed according to the type of surgical incision employed. RESULTS: Most severe respiratory disturbances in terms of PaO2 decrease, activating compensatory hyperventilation, pulmonary shunt increase, the highest VAS-pain score and consumption of tramadol were induced by the following upper abdominal incisions: transversal laparotomy according to Orr, elliptic periumbilical laparotomy, upper midline laparotomy, transrectal laparotomy and subcostal laparotomy. In the group of low abdominal surgery (low midline laparotomy and inguinal incision) consumption of tramadol was statistically significantly lower, but no statistically significant differences were recorded between the baseline preoperative and postoperative values of PaO2, PaCO2 and pulmonary shunt. CONCLUSIONS: All low abdominal incisions were found to entail statistically significantly less respiratory disturbances, lower VAS-pain score and lower tramadol use when compared to upper abdominal incisions. The upper abdominal incisions observed caused substantial respiratory disturbances including hypoxia, hyperventilation and pulmonary shunt increase.  相似文献   
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Hereditary juvenile megaloblastic anemia due to vitamin B12 (cobalamin) deficiency is caused by intestinal malabsorption of cobalamin. In Imerslund-Grasbeck syndrome (IGS), cobalamin absorption is completely abolished and not corrected by the administration of intrinsic factor (IF); if untreated, the disease is fatal. Biallelic mutations either in the cubilin (CUBN) or amnionless (AMN) gene cause IGS. In a series of families clinically diagnosed with likely IGS, at least six displayed no evidence of mutations in CUBN or AMN. A genome-wide search for linkage followed by mutational analysis of candidate genes was performed in five of these families. A region in chromosome 11 showed evidence of linkage in four families. The gastric IF (GIF) gene located in this region harbored homozygous nonsense and missense mutations in these four families and in three additional families. The disease in these cases therefore should be classified as hereditary IF deficiency. Clinically, these patients resembled those with typical IGS; radiocobalamin absorption tests had been inconclusive regarding the nature of the defect. In the diagnosis of juvenile cobalamin deficiency, mutational analysis of the CUBN, AMN, and GIF genes provides a molecular characterization of the underlying defect and may be the diagnostic method of choice.  相似文献   
9.
A one-stage reconstruction technique for upper lip defects is presented. This technique uses everted mucosal advancement flaps for the reconstruction of the vermilion border of the lip. It is an extension of Meyer's method employed in the reconstruction of the lower lip (1973) and differs from Camille Bernard's procedure in that horizontal incisions with bilateral triangular skin excisions are used instead of the more unaesthetic perpendicular incisions in the nasolabial fold, leaving a scar along the vermilion border. The method is suitable for reconstructing the upper lip after excision of up to 80% of its substance, and is superior to traditional methods in terms of both the functional and aesthetic results obtained.  相似文献   
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