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41.
BACKGROUND: Tracheotomies are routinely performed for severely ill and elderly patients with respiratory failure. This intervention is questioned, given the poor survival rate in this group. Outcomes analysis is performed after tracheotomy. METHODS: This is a retrospective study of 78 elderly patients, who received tracheotomies for respiratory failure. Pretracheotomy data (age, length of oral intubation, and DNR status) were collected. Outcomes analyzed during the same admission as the tracheotomy included death versus discharge, ventilator dependence, vocal function, route of feeding, decannulation, and ICU discharge disposition. RESULTS: The mean age was 77.6 +/- 11 years (median, 79 years) and patients were intubated for 16.7 +/- 9 days. Forty-two percent (n = 33) obtained DNR orders after tracheotomy, and 8% (n = 6) before tracheotomy. Seventy-one percent of patients (n = 55) had gastrostomy tubes placed. Fifty-six percent of patients (n = 44) died after tracheotomy; median time from tracheotomy to death was 31 days. After tracheotomy, 53 % (n = 41) remained at least partially ventilator dependent, 18 % (n = 14) regained consistent vocal function, and 13 % (n = 10) were decannulated. For those who died, 27 % (n = 12) died without leaving the ICU. CONCLUSION: These data demonstrate that a large proportion of elderly, severely ill patients with respiratory failure suffer poor outcomes after tracheotomy. More stringent criteria are necessary for performing the tracheotomy in this patient population.  相似文献   
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43.
锌酞菁脂质体光动力作用引起小鼠肿瘤的细胞程序性死亡   总被引:3,自引:1,他引:3  
电镜观察了锌酞菁脂质体光动力作用引起小鼠MS-2纤维肉瘤的形态学变化。发现其作用很强,并对肿瘤细胞有明显的直接影响。肿瘤细胞的结构表现出明显的程序性细胞死亡(apoptosis,programmedceldeath)的特点:胞核染色质凝聚边集、核固缩、核破裂、染色质凝块流失、胞质内吞噬现象、胞膜表面肿胀粗钝的胞突形成、细胞碎裂等。加深了对锌酞菁脂质体光敏作用机理的认识,但其详细的发生机制和调节途径有待阐明。  相似文献   
44.
An effect of gene dosage on production of human chorionic somatomammotropin   总被引:3,自引:0,他引:3  
The gene deletions responsible for isolated partial deficiency of fetal human chorionic somatomammotropin (hCS) production were characterized by restriction endonuclease analysis of genomic DNA prepared from the leukocytes of an affected child. The phenotypically normal child was the product of a 38-week pregnancy characterized by peak maternal hCS levels of 1.1 micrograms/microliter (normal, 3-9.2 micrograms/ml) and normal levels of other pregnancy-associated hormones. Two genes, termed hCS-A and hCS-B, specify the same mature hCS peptide and are responsible for fetal hCS production. Digestion of the child's DNA with the enzymes Hind III, Eco RI, Bam HI, Bgl II, Hinc II and Msp I disclosed absence of the restriction fragments that normally contain the hCS-A gene. However, the hCS-B gene was present in the child's DNA. The child's DNA digests contained an abnormally large Eco RI fragment of 10.0 kb containing the hCS-L gene. This abnormal fragment is a marker for a deletion that is responsible for complete deficiency of hCS when present in the homozygous state. The child's DNA restriction patterns were consistent with heterozygosity for two different deletions involving hCS genes. The paternal hGH gene cluster lacked the hCS-A, human GH variant, and hCS-B genes, while the maternal cluster lacked only the hCS-A gene. Thus, the child's DNA contained only one of the normal complement of four functional hCS genes per diploid genome. Material hCS levels approximately one fourth as great as those present at comparable stages of normal pregnancies indicated that there was no compensatory increase in expression of the remaining hCS gene.  相似文献   
45.
Aim An analysis of a multi‐centred database of trauma patients was performed. Method The study used data from a prospective multi‐centre trauma database containing details of 52 887 trauma patients admitted to participating Scottish Hospitals over an 11‐year period. Results Three hundred and forty (0.64%) of 52 887 trauma patients (284 male) with colorectal injuries were identified; 43.9% of colorectal injuries occurred following blunt trauma and 56.1% following penetrating injury. Patients in the latter group were younger, had less haemodynamic compromise and were less likely to die than those with blunt trauma (P < 0.01). The overall mortality rate was 25.6% and after rectal injury it was 21.2% (P > 0.05). Female gender, increased age, road traffic accidents and those admitted as a result of a blunt traumatic injury were associated with increased mortality. Age > 65 years (P = 0.01), increasing injury severity score (ISS) at presentation (P < 0.001), haemodynamic compromise (P = 0.045) and decreased Glasgow Coma Score (GCS) (P < 0.001) had the strongest independent associations with mortality. Conclusion Colorectal injury after trauma has a high morbidity. Clinical features associated with death allow stratification of mortality risk.  相似文献   
46.
Static biomechanical studies have demonstrated that the Ludloff shaft metatarsal osteotomy is significantly more stable than other commonly used proximal (basilar) osteotomies, such as the proximal crescentic and the proximal chevron. High average static bending failure moments have been recorded for the screw fixation Ludloff osteotomy construct. The objective of the current study was to find a reasonable alternative method of fixation in cases where a short osteotomy may not be amenable to adequate screw fixation and in cases where an inadvertent intraoperative fracture of the metatarsal occurs and subsequent screw fixation is precarious due to inadequate bone stock. A Ludloff osteotomy was performed on 24 matched pairs of cadaveric specimens to compare the strength of fixation of three different types of Kirschner wires (smooth, threaded, and SOC threaded). Biomechanical testing with plantar force was carried out, and failure load and stiffness were measured for each specimen. The current results indicate that the threaded pin construct provides adequate strength for fixation of the Ludloff osteotomy in the clinical setting.  相似文献   
47.
Early specialist repair of biliary injury   总被引:9,自引:0,他引:9  
BACKGROUND: Considerable debate surrounds the timing of repair of injury to the common bile duct following cholecystectomy. In the absence of sepsis or significant peritoneal soiling, repair within the first week may be optimal. This study compared the outcome of early (within the first 2 weeks) and delayed (between 2 weeks and 6 months) repair. METHODS: Data on all patients referred with biliary injuries were recorded prospectively. In the absence of sepsis or significant peritoneal soiling, repair was considered within 2 weeks. RESULTS: Between November 1988 and November 2003, 123 patients were referred with injury to the biliary tree. Repair of the injury had been attempted in 55 patients (44.7 per cent) before referral. Of the 68 patients with no previous repair, nine were managed without surgery and 59 required subsequent surgical reconstruction of the ductal injury. Within the first 2 weeks after injury, 22 patients underwent primary biliary repair and three had revision of a failed biliary repair. Between 2 weeks and 6 months, a further 22 injuries were repaired. Successful repair was possible in 22 of 25 early repairs compared with 20 of 22 delayed repairs (P = 0.615). The overall operative mortality rate for patients undergoing repair was 4 per cent (two of 47 patients). CONCLUSION: A successful outcome was achieved in a high proportion of patients (42 of 47) when repair of the bile duct injury was undertaken in a unit experienced in the management of biliary injury. In selected patients, early repair within the first 2 weeks resulted in a similar outcome to that of delayed repair.  相似文献   
48.
A significant study from the USA compares cystine stone formers and routine stone formers; the former group had a higher requirement for therapeutic procedures, but this was less if they took chelating agents, although remaining higher than in the latter group. Other interesting findings are also presented. OBJECTIVE: First, to compare two types of stone formers (SF), those with cystinuria and those without, for effects of treatments for stones, as cystinuria leads to recurrent stones that are difficult to fragment with shock-wave lithotripsy, and there is disagreement about the efficacy of current treatments. Second, to compare these two groups with respect to blood pressure (BP) and renal function, as cystine stones may be associated with more morbidity than are routine stones. PATIENTS AND METHODS: Fifty-two cystinuric patients (cystine SF) entering our programme since 1970 were compared with 3215 SF without cystinuria (routine SF), of whom 114 had a single functioning kidney (routine SF + nephrectomy). All patients had three 24-h urine and blood samples taken to determine the risk of stones before their first clinic visit; these studies were repeated after therapy was initiated, and at regular intervals to monitor therapy. Cystine was measured in the urine samples of the cystine SF. All stone-related procedures were recorded, and BP measured at clinic visits. Creatinine clearances (CCr) were calculated from each set of serum and urine values. Cystine supersaturation (SS) was directly measured in 16 urine samples collected before treatment and 13 afterward. RESULTS: Patients were treated with increased fluid intake, potassium alkali and chelating agents such as alpha-mercapto-propionyl-glycine, as needed. The mean (sd) CCr, corrected for age and gender, was significantly lower at entry in cystine SF than in routine SF, at 91 (6) vs 160 (1) L/day, respectively (P < 0.001), and remained so at the last CCr. Neither systolic nor diastolic BP, similarly corrected, differed between the groups, but cystine SF had significantly more procedures, corrected for time at risk, before treatment than did routine SF, at 4.0 (0.4) vs 1.86 (0.06), respectively (P < 0.001); time-adjusted procedures decreased significantly in both groups during treatment, but remained higher in cystine SF, at 0.88 (0.14) vs 0.23 (0.02), respectively, (P < 0.001). Urine volume and pH were significantly higher in cystine SF than in routine SF, both before and during treatment. Cystine SS decreased during treatment, consistent with the increase in urine volume and decline in procedure rates during treatment. CONCLUSION: Cystine SF have significantly higher procedure rates than routine SF, but procedure rates decline during therapy, although they remain higher than in routine SF. The lower CCr in cystinurics suggests that treatment to prevent stone recurrence and the need for procedures is particularly important, and emphasizes the need for a close follow-up. Use of cystine SS measurements may allow closer monitoring of the effect of treatment on the risk of stone recurrence.  相似文献   
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50.
Background: The treatment of Brown syndrome has been undergoing an evolution toward more effective procedures with fewer operative interventions. Dr Kenneth Wright has introduced a procedure of superior oblique muscle tenotomy with a silicone expander to reduce the incidence of overcorrection. Methods: There was a retrospective study of 20 eyes of 19 consecutive patients with moderate or severe Brown syndrome (Brown syndrome “plus”). Follow-up ranged from 12 to 72 months. The expander, which varies 6 to 10 mm in length, was placed in all patients in the tenotomized superior oblique muscle tendon 5 mm nasal to the nasal border of the superior rectus muscle using 7-0 or 8-0 Prolene suture without violating the inner layer of the intermuscular septum. The intermuscular septum was closed over the silicone expander. Results: One hundred percent of patients had resolution of the down shoot in adduction and some or full ability to elevate the eye in adduction. Twenty percent of patients required reoperation (12.5% using 5-8 mm expanders) for overcorrection. Restriction of downgaze was not seen postoperatively. Patients often show an undercorrection 1 to 6 months postoperatively and improve or occasionally overcorrect at 1 to 2 years postoperatively. One patient with a 10-mm expander extruded the implant. Discussion: Placement of a 5- to 8-mm silicone expander in the tenotomized superior oblique muscle tendon is an effective means of correcting Brown syndrome with a low rate of reoperation. Initial undercorrection should not discourage the surgeon because improvement may continue for up to 3 years. The goal of treatment should be to convert a moderate or severe Brown syndrome (Brown syndrome plus) to a mild Brown syndrome (“true” Brown syndrome). Conclusion: This technique reduces the need for either simultaneous or subsequent inferior oblique muscle weakening and represents an advance in the treatment of Brown syndrome. (J AAPOS 1999;3:328-32)  相似文献   
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