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81.
PURPOSE: High rates of extracapsular tumor extension have been reported with biopsy perineural invasion (PNI), leading some to advocate routine resection of the ipsilateral neurovascular bundle (NVB) with radical retropubic prostatectomy (RRP) to assure negative surgical margins. The contemporary rates of extracapsular tumor extension (ECE) and margin status associated with biopsy PNI were investigated. MATERIALS AND METHODS: The prostate needle biopsies, RRP specimens, and operative reports of 452 consecutive patients undergoing RRP by a single surgeon were reviewed to determine the presence of PNI invasion, presence of ECE, margin status, and preservation of NVB. Patients were excluded from the analysis if they underwent preoperative hormonal ablation or if their original biopsy was not reviewed by the pathologists at our institution. Both univariate and multivariate analyses were performed to determine the effect of PNI on extracapsular extension, the likelihood of performing a bilateral nerve-sparing technique, and the result of a positive surgical margin. RESULTS: In the 402 evaluable cases, based on multivariate models PNI showed only a marginal association with positive surgical margin (+SM) (P = 0.10) and bilateral nerve-sparing (B-NS) (P = 0.07), but was significantly associated with organ confinement (P = 0.03). The odds ratio (OR) of PNI for +SM, although not statistically significant, was 0.36. Although showing a higher level of statistical significance, PNI for OC had an odds ratio of 0.50. Similarly, the odds ratio was 0.54 for B-NS. CONCLUSIONS: Although biopsy PNI alone was associated with a higher probability of ECE, it is not predictive of bilateral nerve-sparing technique or a positive surgical margin in an individual patient.  相似文献   
82.

Background

BCG vaccine is considered to have immunoprophylactic potential in leprosy. However controversy exists about the extent of prophylaxis it provides. In view of this, a study was undertaken to see the evolution of disease in established cases of leprosy who were already vaccinated with BCG and to compare it with the cases of leprosy who were not vaccinated with BCG.

Methods

114 newly diagnosed cases of leprosy were studied. Patients were divided into two groups-BCG vaccinated and non-vaccinated. Clinical diagnosis of leprosy was confirmed by bacteriological and histopathological studies in each case. All patients were given standard anti leprosy treatment and were evaluated monthly for a minimum period of one year.

Results

All the cases were males in the age group of 20 to 50 years. 25.4% of cases had received BCG vaccine and 74.6% were not vaccinated for the same. No significant difference was observed in the incidence of different types of leprosy in vaccinated and non-vaccinated groups. 25.9% cases in non-vaccinated group developed lepra reaction as compared to 13.8% in vaccinated group. The incidence of deformities and disabilities in vaccinated group was only 10.3% as against 18.8% in non-vaccinated group. The rate of bacillary clearance appeared faster in vaccinated group.

Conclusions

Although there is no significant difference in the pattern of different types of leprosy in BCG vaccinated and non-vaccinated cases, there is reduction in the incidence of reactions as well as deformities and disabilities in BCG vaccinated cases as compared to non-vaccinated cases.Key Words: BCG Vaccine, Leprosy  相似文献   
83.

Background

India accounts for approximately 10 million orthopaedically handicapped children and adults with limb deformity. Ilizarov ring fixator could treat most of these deformities.

Methods

Twenty cases of deformities of lower limb managed with Ilizarov technique during period between March 2001 and February 2003 were studied.

Results

55% were in the age group of 11-30 years. Out of the 20 cases studied, 6 were congenital talipes equino varus, 8 were fixed flexion deformity of knee, 4 were equines deformity of the ankle and 2 were malunited fracture shaft of tibia.4 patients who had recurrence were operated for fixed flexion deformity of the knee. The main complication encountered was pin tract infection, which was seen in 15(75%) cases. In 16(80%) cases, the results were excellent with no recurrence of deformity and patients were able to walk independently. In 4 (20%) cases, recurrence was mild to moderate (10 to 20) but all of them were able to ambulate idependently and carry out their routine activities.

Conclusion

Ilizarov ring fixator is a superior compared to conventional methods for correction of deformities of lower limb.Key Words: Ilizarov method, Ligamentotaxis, Distraction  相似文献   
84.
BACKGROUND: Preoperative biliary stenting is associated with bacterial contamination of bile and an increased rate of infectious complications after pancreaticoduodenectomy. Preoperative drainage has been found to have conflicting effects on morbidity and mortality, and no studies have been published on the effect of stent complications and duration of stenting on postoperative outcome. This study examined the effects of preoperative biliary stenting on early outcome after pancreaticoduodenectomy. METHODS: Details of 144 patients undergoing pancreaticoduodenectomy from 1992 to 2001 were entered into a database. Variables included biliary stenting, duration of stenting, stent complications and bile culture results. Details of surgery and postoperative complications were noted. Patients were grouped as stented and non-stented. Factors likely to affect postoperative mortality and morbidity were analysed. RESULTS: Preoperative biliary stenting was performed in 74 of the 144 patients; post-stenting complications developed in 18 patients (24 per cent) before surgery. After surgery there were nine deaths (6.3 per cent) and 60 (41.7 per cent) of the 144 patients developed complications, with no significant difference in morbidity rate between stented and non-stented patients. Logistic regression showed that a positive intraoperative bile culture was the only factor significantly associated with operative morbidity (P < 0.001) and mortality (P = 0.019). Biliary stenting was not significantly associated with a positive culture (P = 0.073), but stenting that resulted in complications (P = 0.006) and drainage for less than 6 weeks (P = 0.011) was associated with significantly greater culture positivity. Stenting followed by complications was shown by logistic regression to be the only factor significantly associated with a positive culture (P = 0.012). CONCLUSION: A positive intraoperative bile culture was associated with higher morbidity and mortality rates following pancreaticoduodenectomy. A positive culture in the stented group was related to stent complications and duration of stenting. Uncomplicated stenting was not associated with increased morbidity or mortality.  相似文献   
85.
The African trypanosome possesses a total of 16 small GTPases of the Rab family, which are involved in control of various membrane transport events. Recently the roles of these proteins in the endocytosis and recycling of the major surface antigen of the bloodstream form, the variant surface glycoprotein (VSG), have been described but little has been reported on the roles of Rab proteins in exocytic pathways in trypanosomatids. Whilst phylogenetic analysis based on sequence similarity indicates a comparatively well conserved core set of Rab proteins, the evolutionary distance of the trypanosome lineage from crown eukaryote model systems requires direct experimental evidence to support these sequence data. By database searching we identified two further Rab genes, TbRAB1 and TbRAB2, which are the trypanosome sequence orthologues of mammalian Rab1 and Rab2, important mediators of ER to Golgi and intra-Golgi transport processes. A remarkably high level of sequence conservation is retained between the trypanosome and higher eukaryote orthologues. By immunolocalisation we find that both TbRAB1 and TbRAB2 reside on membranes in intimate association with the Golgi complex. By heterologous expression in mammalian cells we also demonstrate conservation of targeting information in the TbRAB1 and TbRAB2 proteins, whilst TbRAB1, but not TbRAB2, can complement a Ypt1(ts) conditional mutant in Saccharomyces cerevisiae. The roles of TbRAB1 and TbRAB2 in exocytosis were examined using RNAi. Suppression of TbRAB1 or TbRAB2 was strongly inhibitory to growth and most importantly both TbRAB1 and TbRAB2 were required for normal progression of VSG through the early secretory pathway. These data indicate conservation of function for these proteins between trypanosomes and crown eukaryotes.  相似文献   
86.
A total of 50 patients undergoing cancer treatment at Malignant Disease Treatment Centre were included in the present study aimed at evaluating the psychological status of cancer patients. All patients filled a specially designed proforma and the following psychological questionnaires : General Health Questionnaire, Carroll Rating Scale for Depression, State-Trait Anxiety Inventory, PGI General Well-being Scale and Quality of Life Scale. Analysis of the results showed that 22 (44%) of the cancer patients had psychiatric disorders and this number had reduced to 12 (24%) after therapy. The difference was statistically significant. Psychiatric treatment also resulted in a statistically significant reduction in level of depression as measured by Carroll Rating Scale for depression. Short term psychiatric treatment was found to be very useful in treating psychiatric morbidity and depression in cancer patients.Key Words: Cancer, Depression, Psychiatric morbidity  相似文献   
87.
Sulforaphane (SFN), a constituent of cruciferous vegetables, is highly effective in affording protection against chemically induced cancers in animal models. Here, we report that SFN inhibited proliferation of cultured PC-3 human prostate cancer cells by inducing apoptosis that was characterized by appearance of cells with sub-G0/G1 DNA content, formation of cytoplasmic histone associated DNA fragments and cleavage of poly(ADP-ribose)polymerase (PARP). SFN-induced apoptosis was associated with up-regulation of Bax, down-regulation of Bcl-2 and activation of caspases-3, -9 and -8. SFN-induced apoptosis, and cleavage of procaspase-3 and PARP were blocked upon pre-treatment of cells with pan caspase inhibitor z-VADfmk, and specific inhibitors of caspase-9 (z-LEHDfmk) and caspase-8 (z-IETDfmk) suggesting involvement of both caspase-9 and caspase-8 pathways in SFN-induced cell death. Oral administration of SFN (5.6 micro mol, 3 times/week) significantly inhibited growth of PC-3 xenografts in nude mice. For instance, 10 days after starting therapy, the average tumor volumes in control and SFN-treated mice were 170 +/- 13 and 80 +/- 14 mm3, respectively, reflecting a >50% reduction in tumor volume due to SFN administration. To the best of our knowledge, the present study is the first published report to document in vivo anticancer activity of SFN in a tumor xenograft model.  相似文献   
88.
Investigations were carried out to evaluate if hydrophytes (viz. Ceratophyllum, Wolffia, and Hydrilla) can be used as markers to assess the level of heavy metal pollution in aquatic bodies. The potential of these hydrophytes for lipid peroxidation and accumulation of proline in response to cadmium (Cd2+) pollution was studied. Hydrophytes were raised in artificial pond water (APW) supplemented with various levels of Cd2+. Interestingly, unlike mesophytes none of the hydrophytes showed ability to accumulate proline. Infact, in response to Cd2+ pollution hydrophytes exhibited a decline in proline levels in comparison to controls but mesophytes (viz. Brassica juncea, Vigna radiata and Triticum aestivum) showed progressive increase in the level of proline with increase in the extent of Cd2+ pollution. Mesophytes showed six to nine-fold increase in the level of proline in response to 1 mM Cd2+. The potential of the above hydrophytes for lipid peroxidation was also low under Cd2+ stress. In contrast, as expected a significant enhancement in the lipid peroxidation was observed in all three mesophytes in response to their exposure to Cd2+. About two-fold increase in production of malondialdehyde (a cytotoxic product of lipid peroxidation) was recorded in mesophytes exposed to 1 mM Cd2+. However, a decline in chlorophyll (Chl a and Chl b) levels was recorded in response to Cd2+pollution both in hydrophytes as well as mesophytes. In summary, hydrophytes neither have potential to accumulate proline nor have ability to accelerate lipid peroxidation under heavy metal stress. This suggests that the adaptive mechanism(s) existing in hydrophytes to tackle heavy metal stress is distinct from that in mesophytes.  相似文献   
89.
BACKGROUND: Survival of Helicobacter pylori is dependent upon urease in the cytoplasm and at the bacterial surface. We have sought to clarify how alkaline ammonium salts, released from urea by this enzyme, might alter mucus pH and so affect growth and motility of the bacterium in the gastric mucus environment. METHODS: Experiments were conducted in vitro to determine how the growth and motility of H. pylori are affected by changes in external pH, and how the bacterium, by hydrolysing urea, alters the pH of the bicarbonate buffer that occurs at the gastric mucosal surface. These data were fitted into experimental models that describe how pH varies within the mucus layer in the acid-secreting stomach. RESULTS: H. pylori was motile between pH 5 and 8, with optimal motility at pH 5. It grew between pH 6 and 8, with optimal growth at pH 6. The bacterium had urease activity between pH 2.7 and 7.4, as evidenced by pH rises in bicarbonate-buffered solutions of urea. Changes in buffer pH were dependent upon initial pH and urea concentration, with the greatest rate of pH change occurring at pH 3. Modelling experiments utilizing these data indicated that (1) in the absence of urease, H. pylori growth and motility in the mucus layer would be restricted severely by low mucus pH in the acid-secreting stomach, and (2) urease will sometimes inhibit H. pylori growth and motility in the mucus layer by elevating the pH of the mucus environment above pH 8. CONCLUSIONS: Urease is essential to the growth and motility of H. pylori in the mucus layer in the acid-secreting stomach, but, paradoxically, sometimes it might suppress colonization by raising the mucus pH above 8. This latter effect may protect the bacteria from the adverse consequences of overpopulation.  相似文献   
90.
In a prospective analysis of ocular fireworks injuries over three consecutive years (1997 to 1999) during the Indian festival of Diwali, 42 patients presented with various types of fireworks-related ocular injuries. Twenty two (52%) patients had to be admitted for the management of their ocular injuries.  相似文献   
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