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51.
In human in-vitro fertilization (IVF)-embryo transfer, the in-vitro culture environment differs from in-vivo conditions in that the oxygen concentration is higher, and in such conditions the mouse embryos show a higher concentration of reactive oxygen species (ROS) in simple culture media. ROS are believed to cause damage to cell membranes and DNA fragmentation in somatic cells. This study was conducted to ascertain the level of H2O2 concentration within embryos and the morphological features of cell damage induced by H2O2. A total of 62 human oocytes and embryos (31 fragmented, 15 non-fragmented embryos, 16 unfertilized oocytes) was obtained from the IVF-embryo transfer programme. The relative intensity of H2O2 concentrations within embryos was measured using 2',7'-dichlorodihydrofluorescein diacetate by Quanti cell 500 fluorescence imaging and DNA fragmentation was observed with transmission electron microscopy and an in-situ apoptosis detection kit. The H2O2 concentrations were significantly higher in fragmented embryos (72.21 +/- 9.62, mean +/- SEM) compared to non-fragmented embryos (31.30 +/- 3.50, P < 0.05) and unfertilized oocytes (30.75 +/- 2.67, P < 0.05). Apoptosis was observed only in fragmented embryos, and was absent in non-fragmented embryos. Electron microscopic findings confirmed apoptotic bodies and cytoplasmic condensation in the fragmented blastomeres. We conclude that there is a direct relationship between increased H2O2 concentration and apoptosis, and that further studies should be undertaken to confirm these findings.   相似文献   
52.

Background  

Catheters are the most common cause of nosocomial infections and are associated with increased risk of mortality, length of hospital stay and cost. Prevention of infections and fast and correct diagnosis is highly important.  相似文献   
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54.
Smith  TP; Cragg  AH; Berbaum  KS 《Radiology》1989,170(3):941
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57.
Seventy-two patients with chest pain and negative exercise tests were observed. Twenty-one (29 per cent) became pain free but 51 (71 per cent) continued to complain of chest pain. Patients with persistent pain were significantly more anxious and depressed at presentation and later compared with those who had become pain free. Anxiety and particularly depression, at presentation and later, were significantly associated with severe symptoms. Patients with chest pain associated with neurosis and depression are not reassured by physiological stress testing because their physical symptoms are a feature of underlying psychiatric disease.  相似文献   
58.
Background: Low serum testosterone is associated with several cardiovascular risk factors including dyslipidaemia, adverse clotting profiles, obesity, and insulin resistance. Testosterone has been reported to improve symptoms of angina and delay time to ischaemic threshold in unselected men with coronary disease.

Objective: This randomised single blind placebo controlled crossover study compared testosterone replacement therapy (Sustanon 100) with placebo in 10 men with ischaemic heart disease and hypogonadism.

Results: Baseline total testosterone and bioavailable testosterone were respectively 4.2 (0.5) nmol/l and 1.7 (0.4) nmol/l. After a month of testosterone, delta value analysis between testosterone and placebo phase showed that mean (SD) trough testosterone concentrations increased significantly by 4.8 (6.6) nmol/l (total testosterone) (p = 0.05) and 3.8 (4.5) nmol/l (bioavailable testosterone) (p = 0.025), time to 1 mm ST segment depression assessed by Bruce protocol exercise treadmill testing increased by 74 (54) seconds (p = 0.002), and mood scores assessed with validated questionnaires all improved. Compared with placebo, testosterone therapy was also associated with a significant reduction of total cholesterol and serum tumour necrosis factor α with delta values of −0.41 (0.54) mmol/l (p = 0.04) and −1.8 (2.4) pg/ml (p = 0.05) respectively.

Conclusion: Testosterone replacement therapy in hypogonadal men delays time to ischaemia, improves mood, and is associated with potentially beneficial reductions of total cholesterol and serum tumour necrosis factor α.

  相似文献   
59.
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   
60.

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   
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