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71.
Penciclovir (PCV) and acyclovir are acyclic guanine analogs which inhibit herpes simplex virus (HSV) DNA polymerase. Their 50% infective doses were 0.5 to 0.8 microgram/ml for clinical isolates of HSV-1 and 1.3 to 2.2 micrograms/ml for HSV-2. Furthermore, HSV-infected cultures receiving 2-h pulses of PCV had 2- to 50-fold less HSV than acyclovir-treated cultures, consistent with the prolonged intracellular half-life of PCV triphosphate.  相似文献   
72.
With advancement in laparoscopic surgery a number of surgical procedures can be performed combined with laparoscopic cholecystectomy in a single surgery. We evaluate the safety & efficacy of such surgeries. A retrospective review of all patients who had undergone combined procedures with laparoscopic cholecystectomy during January 2005 to June 2009 was performed. 3144 laparoscopic cholecystectomies were performed in the period from January 2005 to June 2009. Of these, 401 cases were combined with another procedure. The mean operative time was 80 min (range 50–270 min). The mean hospital stay was 3.2 days (range 1–5 days). The mean no. of days injectable analgesics was required was 2 days (range 1 day–4 days). Combined procedures provide patients with all the benefits of minimal invasive surgery and also give the benefit of single time anaesthesia without adding to post operative morbidity & hospital stay.  相似文献   
73.

Background:

There is no prospective randomized data comparing laparoscopic to open hepatectomy. This study compared short- and long-term outcomes in patients undergoing hepatectomy for colorectal metastases (CRM), who were suitable for either laparoscopic or open surgery.

Methods:

Data were prospectively collected from consecutive patients undergoing hepatic resection of CRM at a single centre (1987–2007). Patients who were suitable for laparoscopic resection (Group 1) were compared with patients whose tumour characteristics would best be considered for open resection (Group 2).

Results:

Out of 1152 hepatectomies, 266 (23.1%) were deemed suitable for a laparoscopic approach. The median (IQR) number of metastases was greater in Group 2 [2(1–20) vs. 1(1–10), P < 0.001], as was the mean (SD) tumour size [5.3(3.6) cm vs. 3.3(1.2) cm, P < 0.001]. The median (IQR) operation time [210 (70) min vs. 240 (90) min, P < 0.001] and blood loss [270 (265) ml vs. 355 (320) ml, P < 0.001] were less in Group 1. There was no difference in length of stay, morbidity or mortality. Patients in Group 2 had a higher R1 resection rate (14.9%) compared with Group 1 (4.5%, P < 0.001) and lower 5-year survival (37.8% vs. 44.2%, P= 0.005).

Discussion:

Current criteria for laparoscopic hepatectomy selects patients who have more straight-forward surgery, with less risk of an involved resection margin and better long-term survival, compared with patients unsuited to a laparoscopic approach. Clearly defined criteria for laparoscopic hepatectomy are essential to allow meaningful analysis of outcomes and the results of unrandomized series of laparoscopic hepatectomies must be interpreted with caution.  相似文献   
74.
Chronic joint pain affects physical well being and can lead to severe psychological and social problems, therefore successful long-term management is highly sought-after. No current behavioural measures of pain used in pre-clinical models mimic the clinical dolorimeter, which provides an objective measure of joint hypersensitivity. In this study we aim to use a novel behavioural readout alongside an established measure to mimic the multifactorial measurements taken in the clinic. Using the pressure application measurement (PAM) device a gradually increasing squeeze was applied across the knee joint of rats until the animal gave an indication of pain or discomfort. PAM and the incapacitance tester were used to detect joint hypersensitivity in a well-established rodent model of adjuvant-induced arthritis. Subsequently, the analgesic effects of prednisolone (1, 3 or 10 mg kg(-1)), morphine (3 mg kg(-1)) and celecoxib (15 mg kg(-1)) were assessed. Both PAM and the incapacitance tester detected a reversal of hypersensitivity 1h post-drug administration. Furthermore, the two readouts were highly correlated, and power analysis indicated that PAM was highly reproducible. In conclusion, PAM provides a novel, accurate behavioural tool for detecting a primary mechanical hypersensitivity in a rat model of chronic inflammatory joint pain.  相似文献   
75.

Background and purpose:

Chemokines orchestrate neutrophil recruitment to inflammatory foci. In the present study, we evaluated the participation of three chemokines, KC/CXCL1, MIP-2/CXCL2 and LIX/CXCL5, which are ligands for chemokine receptor 2 (CXCR2), in mediating neutrophil recruitment in immune inflammation induced by antigen in immunized mice.

Experimental approach:

Neutrophil recruitment was assessed in immunized mice challenged with methylated bovine serum albumin, KC/CXCL1, LIX/CXCL5 or tumour necrosis factor (TNF)-α. Cytokine and chemokine levels were determined in peritoneal exudates and in supernatants of macrophages and mast cells by elisa. CXCR2 and intercellular adhesion molecule 1 (ICAM-1) expression was determined using immunohistochemistry and confocal microscopy.

Key results:

Antigen challenge induced dose- and time-dependent neutrophil recruitment and production of KC/CXCL1, LIX/CXCL5 and TNF-α, but not MIP-2/CXCL2, in peritoneal exudates. Neutrophil recruitment was inhibited by treatment with reparixin (CXCR1/2 antagonist), anti-KC/CXCL1, anti-LIX/CXCL5 or anti-TNF-α antibodies and in tumour necrosis factor receptor 1-deficient mice. Intraperitoneal injection of KC/CXCL1 and LIX/CXCL5 induced dose- and time-dependent neutrophil recruitment and TNF-α production, which were inhibited by reparixin or anti-TNF-α treatment. Macrophages and mast cells expressed CXCR2 receptors. Increased macrophage numbers enhanced, while cromolyn sodium (mast cell stabilizer) diminished, LIX/CXCL5-induced neutrophil recruitment. Macrophages and mast cells from immunized mice produced TNF-α upon LIX/CXCL5 stimulation. Methylated bovine serum albumin induced expression of ICAM-1 on mesenteric vascular endothelium, which was inhibited by anti-TNF-α or anti-LIX/CXCL5.

Conclusion and implications:

Following antigen challenge, CXCR2 ligands are produced and act on macrophages and mast cells triggering the production of TNF-α, which synergistically contribute to neutrophil recruitment through induction of the expression of ICAM-1.  相似文献   
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Summary The 101 nucleotide region upstream from the ATG of the potato virus S (PVS) coat protein gene was isolated and the effect of this region on the translation of a downstream open reading frame analysed in vivo. Translation was monitored using the reporter genes B-glucuronidase (GUS) and luciferase (LUC). Translational enhancement was assayed transiently using DNA microprojectile bombardment into both leaf and pollen tissue and also by polyethylene glycol mediated transfection of tobacco protoplasts. In both cases the presence of this region resulted in a 2–3 fold increase in translation when compared to reporter expression with synthetic leader and authentic plant leader constructs. Tobacco plants stabily transformed with this PVS 101 nucleotide region and downstream GUS gene gave 4 times the level of translation over synthetic leader GUS control plants.  相似文献   
80.
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