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101.
Vitamin A therapy has been claimed in isolated reports to be of benefit to patients with Crohn's disease. To investigate this further, 86 patients were entered into a long-term double-blind study of vitamin A, 50,000 U twice daily, as compared with placebo. After a mean of 14.1 mo of treatment there was no significant difference between the groups as measured by a variety of activity indices (including the National Cooperative Crohn's Disease Activity Index), the number of acute attacks, and the surgical rate. No toxic effects of vitamin A were observed during the study. In this study vitamin A has not been shown to be of benefit to patients with Crohn's disease who are in remission.  相似文献   
102.
Two chlorophyll-protein complexes associated with photosystem II (PSII) of the cyanobacterium Anacystis nidulans R2 have been detected. The larger of the two complexes, CPVI-1, contained a 71-kDa and a 42-kDa protein. The 71-kDa protein was determined to be the anchor protein of the phycobilisomes (the light-harvesting complex of A. nidulans PSII), since it was recognized by an antibody raised against a similar protein from another cyanobacterium. The second complex, CPVI-4, contained a previously unobserved 36-kDa chlorophyll-binding protein. Additionally, two other PSII chlorophyll-protein bands were characterized. CPVI-2 contained a 52-kDa band that was recognized by an antibody raised against the presumptive PSII reaction center protein of Chlamydomonas reinhardtii. It gave rise to a fluorescence emission peak (77K) at 695 nm, indicating that this chlorophyll-protein complex may harbor the reaction center of PSII. Finally, CPVI-3 was found to have a 45-kDa protein and to be immunologically related to the presumptive immediate-antenna protein of the C. reinhardtii PSII.  相似文献   
103.
Delta antigen is currently thought to reflect superinfection of the liver with a defective RNA virus (delta agent), requiring helper function from hepatitis B virus for its replication. To assess the influence of delta agent on hepatitis B virus replication in patients persistently infected with both viruses and showing chronic liver disease, we measured serum and liver hepatitis B virus DNA in HBsAg-positive chronic liver disease patients who were either positive or negative for delta antigen in the liver. Hepatitis B virus DNA was assayed in the serum of 21 patients with delta antigen-positive/HBsAg-positive chronic liver disease and in 21 patients with delta antigen-negative/HBsAg-positive chronic liver disease matched for HBeAg/anti-HBe status and underlying liver histology. HBcAg and delta antigen in liver was determined by immunofluorescence or immunoperoxidase staining. In delta antigen-positive/HBsAg-positive chronic liver disease, serum hepatitis B virus DNA was detected transiently in 4 of 21 cases (19%) and was present in these patients at low levels (trace to 2+). In contrast, 9 of 21 (43%) delta antigen-negative/HBsAg-positive chronic liver disease patients were serum hepatitis B virus DNA positive, and five of these had high serum hepatitis B virus DNA levels (3+ to 4+). Serum HBsAg and anti-HBc titers were significantly lower in delta antigen-positive cases and correlated with reduced amount of HBcAg in the liver.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
104.

Purpose:

Biceps tenotomy and tenodesis are effective treatment options for biceps pathology, but outcomes of revision surgery are not known. This study examines the clinical outcomes of patients who have undergone a revision biceps tenodesis.

Materials and Methods:

A retrospective review of all patients since 2004 (N = 21) who had undergone a revision biceps tenodesis with greater than 6-month follow-up was completed. A follow-up survey was carried out, and the visual analog scale (VAS), Single Assessment Numeric Evaluation (SANE), Simple Shoulder Test (SST), American Shoulder and Elbow Surgeons (ASES), and University of California – Los Angeles (UCLA) scores were obtained, along with SF-12 Mental (MCS-12) and Physical Component Summaries (PCS-12).

Results:

Indications for revision surgery were continued pain (14) and ruptured biceps (7). Complete follow-up examinations were performed in 15 of 21 patients (71.4%). Average follow-up was 33.4 ± 23.5 months. The mean postoperative scores were 1.9 out of 10, VAS; 79 out of 100, SANE; 10.2 out of 12, SST; 83 out of 100, ASES; 29 out of 35, UCLA; 44, PCS- 12; and 47.1, MCS- 12. Five patients were considered failures with a UCLA score below 27. Seventeen of twenty-one patient underwent concomitant procedures. Complete preoperative and postoperative data were collected for 14 patients. All scores demonstrated highly significant improvement from preoperative levels (P < 0.005), except for the MCS-12. There was no statistically significant difference in the outcomes of revision due to rupture and revision due to persistent pain.

Conclusions:

The results suggest that revision subpectoral biceps tenodesis provides significant pain relief and improvement in functional outcomes at a mean follow-up of 33.4 months.

Level of Evidence:

Case Series, Level 4.  相似文献   
105.
OBJECTIVE: To compare the diagnostic imaging findings with the histological lesions in upper pole nephrectomy (UPN) specimens of duplex system ureteroceles, using renal ultrasonography (US) and nuclear renal scintigraphy. PATIENTS AND METHODS: Between 1992 and 2000, 86 patients with a ureterocele in a duplex system underwent surgery. The results from US were reviewed in 84 patients by a radiologist, for echogenicity, parenchymal thinning and hydronephrosis; 77 nuclear renal scans describing the differential function of the upper poles were also reviewed. Fifty-five patients underwent UPN (25 antenatal, 30 postnatal; 18 intravesical, 37 extravesical) and the specimens were available for independent review by a pathologist, describing five histological categories, i.e. chronic interstitial inflammation, fibrosis, tubular atrophy, glomerulosclerosis and dysplasia. Histological lesions were categorized as severe (> 25%) or minimal (相似文献   
106.

Purpose

We compared renal function outcomes among patients in the surveillance and intervention arms of the DISSRM registry.

Materials and methods

Patients were grouped into chronic kidney disease stages by estimated glomerular filtration rate range. Cases were considered up staged if a more advanced chronic kidney disease stage was entered during followup. Chronic kidney disease up staging-free survival was compared among groups using Kaplan-Meier analysis and paired comparisons log rank tests. Multivariate Cox regression identified independent predictors of chronic kidney disease up staging-free survival.

Results

A total of 162 patients met the study inclusion criteria, with 68 in the surveillance arm, 65 undergoing partial nephrectomy, 15 undergoing radical nephrectomy, and 14 undergoing cryoablation. Median tumor size was 2.2 cm. Mean estimated glomerular filtration rate change was significantly larger for radical nephrectomy vs. surveillance (?9.2 vs. ?0.5 ml/min/1.73 m2) and for radical vs. partial nephrectomy (?9.2 vs. ?1.9 ml/min/1.73 m2) (P = 0.001). No other groups differed significantly. On Kaplan-Meier analysis, patients undergoing radical nephrectomy had significantly worse chronic kidney disease up staging-free survival vs. those treated with partial nephrectomy (P = 0.029), surveillance (P = 0.007), and cryoablation (P = 0.019). No other groups differed significantly. On multivariate analysis, radical nephrectomy independently predicted poor chronic kidney disease up staging-free survival (odds ratio vs. surveillance 30.6, P = 0.001). Neither partial nephrectomy (P = 0.985) nor cryoablation (P = 0.976) predicted poor chronic kidney disease up staging-free survival relative to surveillance.

Conclusions

Patients in the surveillance arm had superior estimated glomerular filtration rate preservation compared to those in the radical nephrectomy but not the partial nephrectomy arm. In certain patients with small renal masses, surveillance and partial nephrectomy may offer comparable renal functional outcomes. This could be partly attributable to a modest estimated glomerular filtration rate decrease associated with surveillance itself. A thorough understanding of the renal functional impacts of treatment modalities is critical in the management of small renal masses.  相似文献   
107.
Primary extracranial meningiomas are rare neoplasms, frequently misdiagnosed, resulting in inappropriate clinical management. To date, a large clinicopathologic study has not been reported. One hundred and forty-six cases diagnosed between 1970 and 1999 were retrieved from the files of the Armed Forces Institute of Pathology. Histologic features were reviewed, immunohistochemistry analysis was performed (n = 85), and patient follow-up was obtained (n = 110). The patients included 74 (50.7%) females and 72 (49.3%) males. Tumors of the skin were much more common in males than females (1.7:1). There was an overall mean age at presentation of 42.4 years, with a range of 0.3–88 years. The overall mean age at presentation was significantly younger for skin primaries (36.2 years) than for ear (50.1 years) and nasal cavity (47.1 years) primaries. Symptoms were in general non-specific and reflected the anatomic site of involvement, affecting the following areas in order of frequency: scalp skin (40.4%), ear and temporal bone (26%), and sinonasal tract (24%). The tumors ranged in size from 0.5 up to 8 cm, with a mean size of 2.3 cm. Histologically, the majority of tumors were meningothelial (77.4%), followed by atypical (7.5%), psammomatous (4.1%) and anaplastic (2.7%). Psammoma bodies were present in 45 tumors (30.8%), and bone invasion in 31 (21.2%) of tumors. The vast majority were WHO Grade I tumors (87.7%), followed by Grade II (9.6%) and Grade III (2.7%) tumors. Immunohistochemically, the tumor cells labeled for EMA (76%; 61/80), S-100 protein (19%; 15/78), CK 7 (22%; 12/55), and while there was ki-67 labeling in 27% (21/78), <3% of cells were positive. The differential diagnosis included a number of mesenchymal and epithelial tumors (paraganglioma, schwannoma, carcinoma, melanoma, neuroendocrine adenoma of the middle ear), depending on the anatomic site of involvement. Treatment and follow-up was available in 110 patients: Biopsy, local excision, or wide excision was employed. Follow-up time ranged from 1 month to 32 years, with an average of 14.5 years. Recurrences were noted in 26 (23.6%) patients, who were further managed by additional surgery. At last follow-up, recurrent disease was persistent in 15 patients (mean, 7.7 years): 13 patients were dead (died with disease) and two were alive; the remaining patients were disease free (alive 60, mean 19.0 years, dead 35, mean 9.6 years). There is no statistically significant difference in 5-year survival rates by site: ear and temporal bone: 83.3%; nasal cavity: 81.8%; scalp skin: 78.5%; other sites: 65.5% (P = 0.155). Meningiomas can present in a wide variety of sites, especially within the head and neck region. They behave as slow-growing neoplasms with a good prognosis, with longest survival associated with younger age, and complete resection. Awareness of this diagnosis in an unexpected location will help to avoid potential difficulties associated with the diagnosis and management of these tumors.  相似文献   
108.
异基因造血干细胞移植(hematopoieticcelltransplantation,HCT)后代谢综合征的发生主要由预处理导致的神经激素系统紊乱、血管内皮损伤、移植物的免疫和炎症作用以及继发的移植物抗宿主病及其治疗等引起。对代谢综合征及其组分(糖尿病、高血压、血脂紊乱等)的筛查可以尽早地调整治疗策略,控制危险因素的发生,进而降低远期的心血管疾病的发生率和致死率。为此,美国的研究人员回顾性分析了86例异基因HCT受者代谢综合征的发生情况,并与代谢综合征在普通人群中的流行情况进行比较。  相似文献   
109.
An oxygen-enriched atmosphere enhances the potential for operating-room fires. We thus determined oxygen concentrations at various facial landmarks during oxygen administration via nasal cannulae. Thirteen supine volunteers were draped similarly to patients undergoing a cervical-node biopsy. Oxygen was delivered in random order through nasal cannulae at rates of 2, 4, and 6 l.min−1. Oxygen concentration was measured at pre-determined facial landmarks and also distal to the drape at non-facial sites. At a flow of 2 l.min−1, oxygen concentrations exceeded 23% only within a few centimetres of the nasal cannula. Concentration increased as a function of flow, but rarely exceeded 26%. At all flow rates, concentrations distal to the drape were < 24%. To reduce combustion risk, ignition sources should be kept at least 10 cm from the oxygen outlet when using nasal cannula at a flow rate ≥ 4 l.min−1.  相似文献   
110.
BACKGROUND: Mutism has been associated with injury to midline cerebellar structures secondary to degenerative disease, tumors, hemorrhage, or surgery. Typically, cerebellar mutism syndrome (CMS) has been seen in children and only rarely described in adults after surgery of the posterior fossa. This syndrome typically arises 48 hours after the initiating event and resolves approximately 7 to 8 weeks later. Characteristics of CMS include complete absence of speech without impaired consciousness, other cranial nerve deficits, or long tract signs. CASE DESCRIPTION: The authors report on 2 patients each of whom developed cerebellar mutism after tumor resection using a posterior fossa approach. The first patient underwent gross total resection of a pineal region tumor via a supracerebellar approach. The second patient underwent posterior fossa decompression for a left cerebellar hemispheric renal cell carcinoma metastasis with adjacent hemorrhage. One patient displayed a variant of cerebellar mutism with severe ataxic dysarthria without complete absence of speech, whereas the other demonstrated frank mutism. After neuroimaging studies confirmed the absence of a surgically treatable postoperative cause for the patients' symptoms, they were managed in a supportive fashion (eg, speech therapy) and improved within 3.5 months and 1 year, respectively. CONCLUSION: It is paramount that neurosurgeons be aware of cerebellar mutism with regard to its very rare occurrence in adults, its time of onset, and typical self-limiting course.  相似文献   
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