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Municipal wastewater effluent is increasingly used as reclaimed water and source water for downstream areas. Scholars are beginning to study the potential of dissolved organic nitrogen (DON) as a precursor to the formation of nitrogen disinfection by-products (DBP). In order to explore the mechanism of pre-ozonation coupled with enhanced coagulation on DON in the secondary effluent, the distributions of molecular weight and hydrophobicity/hydrophilicity of DON were analyzed. Disinfection by-product formation potential from chlorination was also investigated. Lastly, the composition and chemical structure of DON before and after coagulation were studied in combination with 3DEEM. Our results showed that pre-ozonation followed by coagulation with PACl significantly enhanced the removal of DON and mitigated DBP formation potentials. The following conclusions can be drawn from this study:① The tested effluent was very hard as indicated by total hardness and high calcium concentrations, and the pH had an important effect on pre-ozonation enhanced coagulation. As pH was decreased, the rates of DON, DOC and UV

In order to explore the chlorinated disinfection by-product formation potential and chemical structure of dissolved organic nitrogen compounds in municipal wastewater, the water quality parameters, such as DON, DOC, NH4(+) -N and UV254 etc, were determined in the secondary effluent and the molecular weight distribution of the DON was investigated before and after the reaction with chlorine. DBPs were determined by gas chromatography, and the changes of DON were characterized using Fourier transform infrared spectroscopy and three-dimensional fluorescence spectroscopy before and after the reaction with chlorine. The results showed that DON, DOC, NH4(+) -N and UV254 were 2.47 mg x L(-1), 14.45 mg x L(-1), 5.42 mg x L(-1) and 15.88 m(-1), and m(DOC)/m(DON) and SUVA were 5.85 mg x mg(-1) and 1.09 L x (m x mg)(-1) in the secondary effluent. After the reaction with chlorine, the proportion of small molecular weight (M(r)6 000) DON increased from 78% to 70% , and the proportion of large molecular weight (M(r)20 000) DON decreased from 21% to 14%. The medium molecular weight (M(r)6000-20000) DON accounted for a small proportion and was unchanged. Among the DBPs, the concentration of bromochloroacetonitrile was the highest, which was 6.887 microg x L(-1), and the concentration of trichloroacetonitrile was the lowest, which was only 0.217 microg x L(-1). In FTIR spectrum, the dominating bands were at 3 500-3 400, 2 260-2 200, 1 700-1 640, 1 500-1 450, 1 150-1 100 and 850-800 cm(-1) respectively before the reaction, and the 1 380-1 350 cm(-1) and 600-550 cm(-1) bands were the dominating bands in addition to the original absorbing regions after the reaction. 3DEEM revealed that the variation of DON depends intimately on tryptophan protein-like substances, aromatic protein-like substances and fulvic acid-like substances.

Dissolved organic nitrogen as a precursor of new type nitrogenous disinfection by-products in drinking water attracted gradually the attention of scholars all over the world. In order to explore the mechanism of DON removal in micro-polluted raw water by coagulation and adsorption, water quality parameters, such as DON, DOC, NH4(+) -N, UV254, pH and dissolved oxygen, were determined in raw water and the molecular weight distribution of the DON and DOC was investigated. The variations in DON, DOC and UV254 in the coagulation and adsorption tests were investigated, and the changes of DON in raw water were characterized using three-dimensional fluorescence spectroscopy. The results showed that DON, DOC and UV254 were 1.28 mg x L(-1), 8.56 mg x L(-1), 0.16 cm(-1), and DOC/DON and SUVA were 6.69 mg x mg(-1), 1.87 m(-1) x (mg x L(-1))(-1) in raw water, respectively. The molecular weight distribution of the DON in raw water showed a bimodal distribution. The small molecular weight (6 000) fractions accounted for a high proportion of 68% and the large (20 000) fractions accounted for about 22%. The removal of DON, DOC and UV254 was about 20%, 26% and 70%, respectively, in the coagulation test and the dosage of coagulant was 10 mg x L(-1). The removal of DON, DOC and UV254 was about 60%, 35% and 100%, respectively, in the adsorption test and the dosage of activated carbon was 1.0 g. In the combination of coagulation and adsorption, the removal of DON and DOC reached approximately 82% and 64%, respectively. 3DEEM revealed that the variation of DON in the coagulation and adsorption tests depended intimately on tryptophan protein-like substances, aromatic protein-like substances and fulvic acid-like substances.

In order to explore the mechanism of NH(4+)-N removal in drinking water biofilter, water quality parameters, such as NH(4+)-N, NO(2-)-N, NO(3-)-N, total phosphorus, permanganate index, nitrogen gas, temperature and dissolved oxygen etc, were determined in the inflow and outflow of biofilter. Samples of granular activated carbon (GAC) at different height (0, 10, 20, 40, 60 cm) of the biofiter media were collected and analyzed for the bacterial community with molecular biology techniques. The bacterial diversity in the activated carbon biofilm sample was studied based on the phylogenetic analysis of sequences. The results showed that there were three stages according to the NH(4+)-N concentration in the influent. The "nitrogen loss" phenomenon (total inorganic nitrogen in the effluent was less than that in the influent) occurred at the first, second and third stages and the amount of nitrogen loss were 0.94, 0.32 and 0.15 mg x L(-1), respectively. The amount of nitrogen loss had a good positive correlation with the NH(4+)-N concentration in the influent, but not a linear relationship with the concentration of the permanganate index in the influent. The average concentrations of N2 increased gradually with the height of media in the biofilter, with values of 14.04 and 14.67 mg x L(-1) in the influent and the effluent, respectively. Based on the sequencing results, the ammonia-oxidizing bacteria (AOB) in the activated carbon biofilm were classified into three common genera: Nitrosococcus, Nitrosomonas and Nitrosospira. When the NH(4+)-N concentration in the influent was relatively high, the "nitrogen loss" phenomenon in biofilter was caused by the AOB.

To explore the feasibility of laparoscopic-assisted radical right hemicolectomy with the outcome being a complete mesocolic excision (CME).Between February 2010 and June 2011, we performed the standardized surgery of laparoscopic-assisted radical right hemicolectomy with an aim of CME on 14 patients. There were 10 males and 4 females, with an average age of 57 years (range 36 to 74 years). All the pathologic results in 14 cases were primary colonic adenocarcinoma. The TNM stages were distributed as follows: 2 in II A, 3 in II B, 3 in III A, 5 in III B and 1 in III C.Surgery was successfully performed for all patients without open conversion. The average operation time was (178 ± 37) minutes (range 127 to 221 minutes), average intraoperative blood loss was (67 ± 23) ml (range 30 to 110 ml), while the average number of lymph node harvest was 21 ± 7 (range 14 to 31), and the postoperative hospital stay was (10.0 ± 2.2) days (range 7 to 15 days). Minor complications occured in 2 patients. Major complications and post-operative mortality were not observed. All the patients were followed up for 3 to 19 months, no tumor recurrence or metastasis was identified.The standardized surgery of laparoscopic-assisted radical right hemicolectomy with the final outcome of CME is safe and feasible.

This study was to investigate an operation, in which removing breast cysts of foreign body resulted from augmentation with polyacrylamide hydrogel injection was performed simultaneously with silicone prosthesis implantation under SEPS endoscope in order to relieve tissue injury and increase the accuracy of clearance.Eight patients were included in this study. Preoperative type B ultrasound examination was performed to mark the mass. Through an axillary approach, the cysts of foreign body that were distributed in the subcutaneous tissue, breast or muscle were separated and ablated under SEPS endoscope. After removal of the foreign body, a silicone implant was located submuscularly for breast augmentation.The operations were completed without hematoma and infection. Follow-up of the eight patients for 3 to 12 months showed that preoperative symptoms relating to the injected material, such as breast pain, lump and asymmetry, have no longer existed. The shapes of the breasts were satisfactory.We believe that endoscope-assisted mammoplasty offers more satisfactory clinical results with less injury, less morbidity, less scars, more accuracy and greater patient acceptance.

Assimilable organic carbon (AOC) test and bacterial regrowth potential (BRP) analysis were used to investigate the effect of phosphorus on bacterial regrowth in the drinking water that was made from some raw water taken from a reservoir located in northern China. It was shown that AOC of the drinking water samples increased by 43.9%-59.6% and BRP increased by 100%-235% when 50 microg/L PO4(3-)-P(as NaH2 PO4) was added alone to the drinking water samples. This result was clear evidence of phosphorus limitation on bacteria regrowth in the drinking water. This investigation indicated the importance of phosphorus in ensuring biological stability of drinking water and offered a novel possible option to restrict microbial regrowth in drinking water distribution system by applying appropriate technologies to remove phosphorus efficiently from drinking water in China.

One therapeutic paradigm for cocaine abuse is a 24-h 'agonist' treatment which reduces reinforcing effects in a manner similar to the methadone maintenance model for heroin. However, 24-h dosing of dopamine (DA) agonists may induce side effects of insomnia and psychosis, as well as anergia and anhedonia which may actually potentiate abuse. Thus, it is important to determine the daily dose duration of potential treatments such as direct (e.g. pramipexole) and indirect (e.g. GBR 12909) DA agonists, that may induce cross-tolerance with cocaine. We gave a cocaine challenge (15 mg/kg i.p.) on withdrawal day 7 and recorded ambulations and a behavioral rating. We found that 20- and 24-, but not 16-h, daily dosing with cocaine (40 mg/kg), for 14 days, induced tolerance. Pramipexole (4 mg/kg), administered for 24 but not 12 h per day, for 14 days, induced cocaine cross-tolerance while GBR 12909 (18 mg/kg), administered i.p. over 24 or 16 h a day, for 7 days, did not. Thus daily dosing duration is an important variable in consideration of stimulant abuse treatment.

A significant release of oxytocin has been measured in the olfactory bulb of sheep during parturition [1]. The olfactory bulb has also been implicated in the control of maternal behavior in rodents and maternal recognition in sheep [2]. In order to clarify the role of oxytocin in the processing of olfactory information, we examined the effects of electrical stimulation of the hypothalamic paraventricular nucleus (PVN; 0.4–1.0 mA, 100 Hz, 5–30 pulses) on the spontaneous firing of mitral and granule cells in the main olfactory bulb in the rat.

We attempted to transplant a vein graft to normal lymphatics (LVL) to investigate whether it could survive and remain joined to the lymphatics as the environment changed. A total of 152 rabbits were divided into 3 groups. Group 1 was an LVL saline-irrigated group (n = 40), with a patency rate of 52.5%. Group 2 was an LVL nonirrigated group (n = 34), with a patency rate of 29.4%. Group 3 was an LV group (n = 78), with a patency rate of 32%. All specimens were examined under either light microscope or scanning electron microscope. The data indicated that an LVL anastomosis is practical and that preanastomotic irrigation can improve the patency rate. In both the LVL and the LV groups, endothelial regeneration, originating from the adjacent endothelium, commenced within 1 week after the anastomosis, with complete healing within 3 to 4 weeks. The vein graft tended to become "lymphaticized." Thrombosis was the main cause of obstruction. The patency rate can be increased by irrigation of the ends with saline before performing the anastomosis. The graft intima must be kept intact, the nutritive blood vessels of the lymphatics must be preserved, and the flow must be artificially increased soon after the anastomosis.

Lymphedema of the extremity is a chronic and obstinate disease which causes much distress to the patient. In the past 50 years various methods of surgical treatment have been tried, but none of them is satisfactory. However, the method of excising diseased tissues and skin graft has still been widely accepted. Under the influence of the development of microsurgery in recent years, lymphaticovenous anastomosis (LYA) in an attempt to bypass lymphatic blockage has been employed. This operation seems to be a more rational method for the reestablishment of lymphatic drainage.1

With progress in microsurgery, successful microsurgical replantation of the penis has been reported in the literature1–3. Here we report a successful replantation of an amputated penis by use of microsurgical technique.

Bilateral oophorectomies, an integral part of en bloc excision of malignant ovarian tumor, acceptable to elderly women, can hardly be tolerated by young women for whom prolonged estrogen substitution therapy is necessary to overcome endocrine disturbance. Subcutaneous ovary allograft was advocated by some, but ischemia and rejection of the transplant made the positive result only temporary. Following the introduction of microsurgery, vascularized autograft of the fallopian tube and ovary succeeded in animal experiments. No successful case of ovary homograft has ever been reported clinically. A case of homologous vascularized ovary transplantation succeeded perfectly in 1979 in our clinic.

Development and advances in clinical and research work on limb lymphedema in China has progressed rapidly in recent years. The authors first performed successful lymphaticovenous anastomosis using the operating microscope for limb lymphedema in China in May, 1979. By 1983, surgery on 48 lymphedematous limbs in the authors' clinic had given good results in one-third of the cases. By the same year, 185 limbs with lymphedema were treated by lymphaticovenous anastomosis throughout China with excellent results achieved in 72.9% of the cases. Lymphology was investigated using animal models, intraluminal pressure, and venous graft substitution of lymphatics.