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BACKGROUND: Recent studies have suggested that local recurrence rates following rectal cancer surgery are reduced if the mesorectum is removed intact within its fascia propria. The present study aims to compare the outcomes of conventional surgery for rectal cancer and surgery in which the rectum and mesorectum are removed by the technique of extrafascial excision (EFE). METHODS: All patients undergoing surgery for rectal cancer at Auckland Hospital from 1980 to 1996 were identified. Demographic, tumour, operation, outcome, survival and follow-up data were obtained from patient charts, New Zealand (NZ) Death Registry, death certificates and the NZ Electoral Roll. Complication rates, recurrence rates, overall and cancer-free survival and treatment costs were calculated for each group. RESULTS: A total of 262 patients had curative surgery (138 had conventional surgery, 124 had EFE). The groups were similar with respect to age, sex, operation performed and Dukes' stage. There was no difference in complication rates between the groups. Mean follow-up was 7 years in survivors. Twenty-nine conventional-surgery (21%) and eight EFE (6%) patients developed local pelvic recurrence. The 5-year actuarial local recurrence rates were 30% and 10%, respectively (P = 0.0006). The 5-year overall survival was 54% for conventional surgery and 60% for EFE (P = 0.23). The 5-year cancer-free survival was 63% for conventional surgery and 74% for EFE (P = 0.02). Average initial costs were NZ$15,717 and NZ$15,158 for conventional surgery and EFE, respectively. The average cost of local recurrence was an additional NZ$10,471. CONCLUSIONS: The present study adds further support to the growing evidence that excision of the mesorectum within an intact fascial envelope reduces local recurrence rates after surgery for rectal cancer. There appears to be an associated improvement in cancer-free survival. Complication rates and cost were not increased in the patients having EFE.  相似文献   
83.
BACKGROUND: There is controversy about whether diabetes mellitus is a risk factor for pancreatic cancer or an epiphenomenon of the cancer. The present study aims to determine if long-term diabetes is a risk factor for pancreatic cancer. METHODS: The study undertook to determine the prevalence of diabetes among three matched (age/gender) patient groups (pancreatic cancer (PaC), colorectal cancer (CRC), and fracture neck of femur (NOF)) at the date of diagnosis of cancer or fracture as well as 1 and 5 years prior to this. A retrospective review of the medical records of the three groups of patients was undertaken. Patients identified with PaC in the period July 1994 to February 1998 were age (+/- 5 years)- and gender-matched to patients identified in the same time period with NOF and with CRC. The data were then analysed using McNemar's test for discordant pairs. RESULTS: Over a 44-month period 116 patients with PaC were identified of which 24% had diabetes at the time of diagnosis of their malignancy (NOF, 8%; CRC, 9.5%). There was a statistically significant difference (PaC and NOF, P < 0.01; PaC and CRC, P < 0.01). For a duration of diabetes of > 5 years the prevalence of diabetes fell to 7.8% in the PaC group, to 6% in the NOF group and to 6.9% in the CRC group, with no significant difference between the groups. CONCLUSION: There is no increase in the prevalence of long-standing diabetes mellitus in patients with PaC compared to age- and gender-matched controls with NOF and CRC. The relationship of PaC and diabetes may be an epiphenomenon, rather than diabetes being a risk factor for pancreatic malignancy.  相似文献   
84.
Joint replacement is an established method in the treatment of destroyed, painful, proximal interphalangeal joints. A palmar approach was used in which the main collateral ligaments were preserved, allowing immediate active rehabilitation with enhanced primary lateral stability. Fifty-nine proximal interphalangeal joint silicone arthroplasties in 38 patients with a minimum followup of 12 months were reviewed. Thirty-eight of the 59 joints had implantation from a palmar approach and 21 joints from a dorsal approach. The two groups were well-matched in terms of indication, preoperative range of motion, and patient age. No significant increase in the range of motion was found in either of the patient groups, with an overall average range of motion of 51 degrees postoperatively. There was also no significant difference in the postoperative stability in the two patient groups. The choice of surgical approach at the proximal interphalangeal joint level for the silastic type of implants does not appear to be important. With more sophisticated types of implants in which the integrity of the collateral ligaments is crucial, a palmar approach might be beneficial.  相似文献   
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The cephalostatins and ritterazines comprise a family of structurally related natural products reported by Professors G. R. Pettit and N. Fusetani from 1988 -1998. Isolated from the invertebrate marine chordates Cephalodiscus gilchristi and Ritterella tokioka, the cephalostatins and ritterazines exhibit potent cytotoxicity toward the murine P388 lymphocytic leukemia cell line. In fact, cephalostatin 1 ( 1, ED 50 0.1-0.001 pM) proved to be one of the most powerful cancer cell growth inhibitors ever tested by the U.S. National Cancer Institute. The ritterazines and cephalostatins share many common structural features in which two highly oxygenated steroidal units with side chains forming either 5/5 or 5/6 spiroketals are fused via a pyrazine core. Professor P. L. Fuchs and colleagues reported the total syntheses of 1, cephalostatins 7 ( 7), and 12 ( 12), ritterazines K ( 30) and M ( 32), and cytotoxic analogues. The synthesis of 1, described in 1998, required 65 synthetic operations to complete.  相似文献   
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We investigated the prevalence of abnormal screening results (questionnaire and testing for other causes of oligo-ovulation, male or tubal factor infertility) in a group of 1,313 oligo-ovulatory women (included and excluded subjects) whose condition was screened for inclusion in the Pregnancy in Polycystic Ovary Syndrome trial, a multicenter clinical trial that was conducted at 13 sites in the United States. Other than failure to demonstrate laboratory evidence of hyperandrogenemia, the most common reasons for subject exclusion were persistent oligospermia and tubal factor infertility.  相似文献   
90.
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