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71.
Water and electrolyte contents, cell pH and membrane potentials of cultured turtle thyroid cells 总被引:2,自引:0,他引:2
Water and electrolyte contents, cell pH, membrane potential and 125I- uptake were determined in cultured follicular cells of turtle thyroid. The Na+, K+ and Cl- concentrations in the cultured thyroid cells were 59.2, 119.0 and 50.9 mmol/l cell water respectively. Treatment with TSH (10 mu./ml for 24 h) increased the K+ and Cl- and decreased the Na+ concentrations in cells. The water and protein contents of these cells were 81.6 and 8.7 g/100 g cells respectively. The cell pH was 6.91. With glass micro-electrodes, the resting membrane potential of thyroid cells cultured in Medium 199 averaged 33.9 +/- 0.63 mV which is slightly higher than 29.8 +/- 1.6 mV as calculated from the data on the uptakes of [14C]methyltriphenylphosphonium and 3H2O by the cells. The potential varied linearly with the log of external K+ concentration (between 15 and 120 mmol/l) with a slope of about 24 mV per tenfold change in K+ concentration. Both TSH and cyclic AMP depolarized the cell membrane. Calculations based on the values for the electrolyte concentrations in cells and in culture medium indicated that Na+, K+ and Cl- were not distributed according to their electrochemical gradients across the cell membrane. Na+ was actively transported out of the cells and K+ and Cl- into the cells. Follicular cells of turtle thyroid cultured in the medium without addition of TSH formed a monolayer. Their iodide-concentrating ability was low and they did not respond to TSH with an increase in iodide uptake. In contrast, cells cultured in medium containing TSH tended to aggregate and organize to form follicles. They had higher ability to concentrate iodide and respond to TSH. 相似文献
72.
Joseph AM McFall M Saxon AJ Chow BK Leskela J Dieperink ME Carmody TP Beckham JC 《Journal of traumatic stress》2012,25(1):10-16
Smoking prevalence among patients with posttraumatic stress disorder (PTSD) is over 40%. Baseline data from the VA Cooperative Studies Program trial of integrated versus usual care for smoking cessation in veterans with PTSD (N = 863) were used in multivariate analyses of PTSD and depression severity, and 4 measures of smoking intensity: cigarettes per day (CPD), Fagerström Test for Nicotine Dependence (FTND), time to first cigarette, and expired carbon monoxide. Multivariate regression analysis showed the following significant associations: CPD with race (B = ?7.16), age (B = 0.11), and emotional numbing (B =0 .16); FTND with race (B = ?0.94), education (B = ?0.34), emotional numbing (B = 0.04), significant distress (B = ?0.12), and PHQ‐9 (B = 0.04); time to first cigarette with education (B = 0.41), emotional numbing (B = ?0.03), significant distress (B = 0.09), and PHQ‐9 (B = ?0.03); and expired carbon monoxide with race (B = ?9.40). Findings suggest that among veterans with PTSD, White race and emotional numbing were most consistently related to increased smoking intensity and had more explanatory power than total PTSD symptom score. Results suggest specific PTSD symptom clusters are important to understanding smoking behavior in patients with PTSD. 相似文献
73.
Sidney Kam‐Hung Yip Chi‐Bon Leung Cheuk‐Chun Szeto Nga‐Yee Lam Chi‐Kwok Chan Yuen‐Fan Tong Chi‐Fai Ng Bonnie Ching‐Ha Kwan Kai‐Ming Chow Eddie Shu‐Yin Chan Simon See‐Ming Hou Alex Wai‐Yin Yu Philip Kam‐Tao Li 《Surgical Practice》2012,16(1):17-21
Objective: In 2009, 1659 patients with end‐stage renal failure in Hong Kong were waiting for a renal transplant. The overall number of renal transplants carried out locally remains low, with an even lower number being live donor donations. Yet, live donor kidney transplantation yields results that are consistently superior to those of deceased donor kidney transplantation, and laparoscopic donor nephrectomy (LDN) is increasingly accepted worldwide as a safe and preferred surgical option. We aim to evaluate the outcome of LDN in our setting, and to compare with that of deceased donors in this retrospective review. Patients and Methods: A total of 12 patients received LDN over the study period of 2006–2009. Standard left transperitoneal LDN was carried out. Grafts including three with double vessels were prepared using the bench technique. The postoperative outcomes up to 1 year for both the donors and the recipients were studied. Contemporary results for the 47 deceased donor kidneys were studied and compared. Results: All donors had an eventful recovery. The operating time was 225.0 ± 67.4 min. The hospital stay was 5.6 ± 2.3 days. The recipient outcomes including hospital stay and creatinine levels at discharge and 1 year were 11 days, 121 umol/L and 116 umol/L, respectively. Specifically, no ureteric stricture or graft loss was noted at the 1‐year follow up. Recipient complications included haematoma (1 patient), renal artery stenosis (1 patient) and redo of vascular anastomosis (1 patient). In contrast, the deceased donor graft recipients had a hospital stay of 11 days, and creatinine levels of 205 umol/L on discharge and 205 umol/L at 1 year, respectively. The delayed graft function rates for the live donor and deceased donors group were 0% and 14.9%, whereas the 1‐year graft survival rates were 100% and 87.2% respectively. Conclusion: The results showed that the donor morbidity rate was low, as reflected by the short hospital stay. Also, the overall parameters of recipients were good. In particular, no ureteric stricture was noted, and graft survival was 100% at 1 year. Living donor kidney transplant program using the laparoscopic technique is a viable option to improve the pool of kidneys for transplantation. 相似文献
74.
75.
Li PK Chu KH Chow KM Lau MF Leung CB Kwan BC Tong YF Szeto CC Ng MM 《Nephrology (Carlton, Vic.)》2012,17(5):514-518
Aim: We aimed to gain an understanding of patient concerns while on a transplantation waiting list in areas with long transplant waiting time. Methods: The study population comprised patients with organ failure on the transplant waiting list in Hong Kong. They were invited to complete a questionnaire survey. Demographic data and waiting time were collected. Respondents rated their chance of getting transplanted, their subjective concerns and feelings, level of happiness and support received. Results: A total of 442 patients on the waiting list for kidney, liver, lung and heart‐lung transplants completed the questionnaire survey. The majority of patients (93.0%) were waiting for kidney transplantation. More than half of the respondents (63.3%) had been waiting for more than 3 years. Patients with longer transplant waiting times had lower self‐estimated chance of receiving a transplant (P = 0.004). Self‐estimated chance of getting transplanted was positively associated with the happiness score (P < 0.0001). Issues of most concerns to the patients waiting for organ transplants were: inconvenience of therapy (48.2%), disease progression (47.9%), burden to family (59.5%) and financial difficulties (52.3%). More female patients on the waiting list (50.0% vs 25.7% in male) reported concerns about suffering associated with the illnesses. 21.7% of patients considered the level of support received inadequate. Conclusions: Our patients had long waiting time for transplantation, which is associated with a lower perceived chance of getting a transplant. Attention to more psychosocial support to these patients waiting for organ transplant is important. Promoting and improving organ donation would be the ultimate way to help these patients. 相似文献
76.
Danforth DN Cowan K Altemus R Merino M Chow C Berman A Chaudhry U Shriver C Steinberg SM Zujewski J 《Annals of surgical oncology》2003,10(6):635-644
Background: Preoperative chemotherapy for stage II breast cancer may reduce locoregional tumors and provides initial treatment for systemic micrometastases. We conducted a prospective, randomized trial to evaluate the ability of intensive preoperative chemotherapy to enhance the outcome of this approach.Methods: Patients with clinical stage II breast cancer (T2N0, T1N1, and T2N1) were prospectively randomized to receive either preoperative or postoperative chemotherapy with five 21-day cycles of fluorouracil, leucovorin calcium, doxorubicin, and cyclophosphamide (FLAC)/granulocyte-colony-stimulating factor. Local therapy consisted of modified radical mastectomy or segmentectomy/axillary dissection/breast radiotherapy, according to patient preference.Results: Fifty-three women were randomized (26 preoperative chemotherapy and 27 postoperative chemotherapy). The objective clinical response rate of the primary tumor to preoperative chemotherapy was 80%, and the pathologic complete response rate was 20%. Preoperative chemotherapy reduced the overall incidence and number of axillary lymph node metastases. There was no difference in the use of breast-conserving local therapy between the two treatment arms. There were 20 local/regional or distant recurrences (9 preoperative and 11 postoperative). There was no difference in the overall or disease-free survival between the preoperative and postoperative chemotherapy arms.Conclusions: Preoperative FLAC/granulocyte-colony-stimulating factor chemotherapy was effective against local/regional tumors in stage II breast cancer but was otherwise comparable to postoperative chemotherapy. 相似文献
77.
Bochicchio GV Baquero F Hsueh PR Paterson DL Rossi F Snyder TA McCarroll K Satishchandran V Dinubile MJ Chow JW 《Surgical infections》2006,7(6):537-545
BACKGROUND: Since 2002, the worldwide Study for Monitoring Antimicrobial Resistance Trends (SMART) has tracked resistance patterns among aerobic and facultative gram-negative bacilli isolated from patients with intra-abdominal infections. Escherichia coli has been by far the most frequently isolated species. METHODS: Antimicrobial susceptibilities for consecutive non-duplicate isolates of aerobic and facultative gram-negative bacilli recovered from intra-abdominal infections were determined by standard broth microdilution techniques. A subanalysis was performed for E. coli isolates from the first three years of the study. RESULTS: A total of 7,002 E. coli isolates were recovered, most commonly from the peritoneal cavity followed by the biliary tract. Susceptibility rates to the 12 antimicrobial agents tested differed among geographic regions, with isolates from Asia/Pacific generally having the highest resistance rates. Overall, extended-spectrum beta-lactamase (ESBL)-producers had a more antibiotic-resistant profile than non-ESBL-producers but usually were susceptible to the carbapenems and amikacin. Community-acquired E. coli strains comprised slightly more than one-half of the isolates and were susceptible to the agents tested more frequently than were hospital-acquired E. coli. CONCLUSIONS: The prevalence of antimicrobial resistance among E. coli isolated from intraabdominal infections is not inconsequential, especially in the Asia/Pacific region. The carbapenems and amikacin were consistently active in vitro against E. coli isolates worldwide, including ESBL-producers. 相似文献
78.
Chow L Rezmann L Imamura K Wang L Catt K Tikellis C Louis WJ Frauman AG Louis SN 《The Prostate》2008,68(6):651-660
BACKGROUND: There is clear evidence of a tissue-based renin-angiotensin system in the prostate and studies to date suggest that AT(1)-receptor blocking drugs inhibit the growth of some prostate cancer cell lines and delay the development of prostate cancer. The present studies examine the action of Ang II in two prostate cancer cell lines and report the presence of functional AT(2)-receptors that regulate the actions of growth factors. METHODS: Immunohistochemistry was used to identify the presence of Ang II and QPCR techniques to examine AT(1)- and AT(2)-receptor mRNA expression in androgen-dependent (LNCaP) and independent (PC3) cell lines. The effects of AT(1)- and AT(2)-receptor activation upon EGF-induced DNA synthesis and ERK2 phosphorylation in these cells were also examined. RESULTS: Functional AT(2)-receptors together with Ang II were identified in both cell lines and stimulation of these receptors inhibited EGF-induced DNA synthesis and ERK2 phosphorylation. AT(1)-receptors, although present in both cell lines, were only functional in LNCaP cells where activation stimulated DNA synthesis. CONCLUSIONS: Functional AT(2)-receptors are present and have the capacity to inhibit EGF-induced prostate cancer cell growth in LNCaP and fast growing androgen-independent PC3 cell lines, whereas functional AT(1)-receptors are found only in LNCaP cells where their activation stimulates DNA synthesis. 相似文献
79.
Aim: Permanent hypoparathyroidism is a debilitating morbidity following thyroidectomy and parathyroid auto‐transplantation has been shown to be effective in preventing permanent hypoparathyroidism. Controversy exists regarding the benefit of routine versus selective auto‐transplantation. We evaluate the outcome of selective parathyroid auto‐transplantation in our hospital. Methods: A retrospective study was conducted to assess the incidence of postoperative hypocalcaemia. Indication for parathyroid auto‐transplant was doubtful viability of parathyroid gland during thyroidectomy. From 1 July 2000 to 30 June 2005, all patients who underwent total, subtotal and completion thyroidectomy were included. Other outcome measures including recurrent laryngeal nerve injury and operative time were also analyzed. Results: A total of 170 bilateral or completion thyroidectomies were performed within this period. Total, subtotal, and completion total thyroidectomies were performed in 103 (60.6%), 62 (36.5%), and five (2.9%) patients, respectively. Median age was 45 years (range 19–82). One hundred and twenty‐four patients (73%) had benign thyroid disease, and 46 patients (27%) had thyroid carcinoma. Parathyroid auto‐transplant was performed in 35 patients (20.6%). Mean operation time was 204 min (range 95–510 min). There was no difference in the operation time between the patients with parathyroid auto‐transplant and those without auto‐transplant (217 vs 200 min, P = 0.229). Transient hypocalcaemia occurred in 31 patients (18.2%) whereas two patients had permanent hypocalcaemia (1.2%). Permanent recurrent laryngeal nerve injury occurred in one patient (0.6%). Conclusions: The adoption of selective parathyroid auto‐transplant during thyroidectomy achieves an extremely low incidence of permanent hypoparathyroidism without excessive transient hypoparathyroidism. 相似文献
80.
Postmastectomy reconstruction with extended latissimus dorsi myocutaneous flap for Hong Kong Chinese
Objective: Because of the smaller breast size of Chinese women, postmastectomy reconstruction without prosthesis by extended latissimus dorsi (LD) flap is potentially more applicable in the Chinese population. Methods: Patients who had undergone immediate postmastectomy breast reconstruction by extended latissimus dorsi flap without prosthesis were retrospectively studied. Surgical complications, aesthetic result and patient satisfaction were evaluated. Results: Ten Asian patients (nine Chinese and one Filipino) underwent extended LD flap for breast reconstruction after mastectomy. There was no total or partial flap failure. Operative complications included seroma in one patient and minor wound edge slough at back wounds in two patients. Simultaneous seroma and minor donor wound slough occurred in another patient. Aesthetic outcome was excellent (n = 5), good (n = 4) and poor (n = 1). Patient satisfaction with the procedure was very satisfied in four, satisfied in four and dissatisfied in two, respectively. All but two patients would recommend the same procedure to their friends or relatives. Conclusion: Extended LD flap can reliably achieve pleasing results with low morbidity. It has more potential to become a competitive alternative to transverse abdominis myocutaneous flap in most Chinese women for postmastectomy reconstruction. 相似文献