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921.
922.
923.
Two cases of subdural hygroma occurred in a series of 77 neuroendoscopic procedures. An 8-year-old boy underwent neuroendoscopic cysto-cisternostomy of a left temporal arachnoid cyst. Routine postoperative magnetic resonance imaging 7 days later showed a large left-sided subdural hygroma without clinical symptoms. During the following 3 months, the subdural hygroma did not resolve spontaneously, so it was drained through a burr hole. A 3-month-old boy with aqueductal stenosis developed bilateral subdural hygromas after third ventriculostomy. Several punctures through the open anterior fontanelle relieved the hygromas but increasing head circumference required ventriculoperitoneal shunting 12 months later. Complications of neuroendoscopic procedures are increasingly reported, including various kinds of bleeding, infections, or damage of neuronal tissue. Only three previous cases of subdural hygroma or hematoma after neuroendoscopic interventions have been reported. The possible etiologies and clinical consequences of this rare complication have to be considered before selecting neuroendoscopy treatment. 相似文献
924.
Functional outcome after isolated acetabular fractures 总被引:4,自引:0,他引:4
OBJECTIVE: To evaluate objectively the effectiveness of current surgical management of displaced acetabular fractures. To provide insight into how these evaluation methods can be used to identify areas in which improvements in surgery and rehabilitation can be pursued to improve patient outcomes. DESIGN: Consecutive case series. SETTING: University medical center. PATIENTS: Fifteen patients were studied, each with an isolated, displaced acetabular fracture treated with a Kocher-Langenbeck approach. MAIN OUTCOME MEASURES: Primary outcome measures included hip muscle strength, including work (Joules/minute) and maximum torque (30 degrees/second) for abductors/adductors and flexors/extensors. Gait analysis of patients and able-bodied cohorts, including stride length, speed, and cadence, were also assessed. Motion analysis during gait was also studied for each body segment, including the trunk, pelvis, hip, knee, and ankle, in the sagittal, frontal, and axial planes. Motion data for the affected side was compared with motion data for the unaffected side, and linear gait findings for the study patients were compared to able-bodied cohorts. An assessment of clinical outcome was performed by completion of a validated Musculoskeletal Function Assessment (MFA) questionnaire and the were results correlated with muscle strength and gait analysis. Secondary outcome measures included adequacy of fracture reduction, radiographic grade, the presence and severity of heterotopic ossification at the time of the most recent follow-up, and passive range of motion of the affected and unaffected hips. RESULTS: No statistical differences in muscle strength for each of the major muscle groups were found when the affected limb was compared with the unaffected limb. No statistical differences were found between the study patients and the able-bodied cohorts with regards to stride length, gait speed, and cadence. The only significant difference found in body segment position was trunk inclination. When the study patients were compared with able-bodied cohorts, the patients tended to walk with greater forward inclination of their trunks; this was true for all phases of gait. Total MFA scores averaged 22 (range, 0-57). Patients could be separated into two separate groups based on their total MFA score. One group (n = 6) had an average MFA score of 7 (range, 0-10), while a second group (n = 9) had an average MFA score of 32 (range, 12-57). The scores of study patients as a whole, and those of each individual group of patients, were compared with known MFA scores for nonpatients and patients in the Orthopaedic Trauma Association/Association for the Study of Internal Fixation (OTA/AO) injury group (hip and thigh). When the muscle strengths of these two groups of patients were compared, all hip flexion and extension variables were significantly weaker in the group with an average MFA score of 32, whereas none of the gait variables were different between the two groups. At an average follow-up of 24 months, seven patients had an excellent radiographic grade, four patients had a good grade, two patients had a fair grade, and two patients had a poor grade. These radiographic grades were in contrast to achieving an anatomic reduction in eleven patients, a satisfactory reduction in three patients, and an unsatisfactory reduction in one patient. Heterotopic ossification was found in eight patients, four patients had Grade 1, and four patients, had Grade 2. No statistically significant differences were observed when each MFA group was compared with each of these radiographic variables. Passive hip range of motion was not statistically different when the affected hip was compared with the unaffected hip. CONCLUSIONS: Standardized muscle strength determination, gait, and motion analysis, and completion of an MFA questionnaire provided a thorough and revealing evaluation of patients who have undergone open reduction and internal fixation (ORIF) of a displaced acetabular fracture. Minimal alterations in body posture and affected limb motion were present in patients displaying relatively normal gait parameters, including stride length, speed, and cadence. Despite dissection of the hip musculature during surgery, normal muscle strength recovery was possible after operative repair of these acetabular fractures. However, functional outcome, as determined by MFA scores, was considerably poorer in those patients with significantly weaker hip flexion and extension strength, compared with those of patients with more desirable MFA scores. Based on the current data, it appears that the use of these and similar evaluation instruments can allow determination of factors that negatively affect outcome (hip flexion and extension strength), which otherwise may remain unknown. It is possible that identification and treatment of these factors will improve the quality of life for patients after this type of injury. 相似文献
925.
Kimball P Wagner B King A Fisher RA Dawson S Cotterell A Posner M 《Clinical transplantation》2002,16(4):290-294
Renal transplant recipients with positive flow cytometric crossmatches (FCXM) face greater risk of early rejection and graft failure. It is clear that the pharmacologic needs of this high risk group have not been identified. We retrospectively compared the impact of two drug regimens upon early rejection and 5 yr actuarial survival among 324 primary cadaveric transplant recipients with positive and negative FCXM. Patients received either Regimen I (OKT3 induction, cyclosporine and steroids) or Regimen II (mycophenolate mofetil with cyclosporine or Prograf). Recipient gender, age, disease etiology, ethnic distribution and cytotoxic panel reactive antibody (PRA) were equivalent between regimens (p=ns). With Regimen I, the incidence of rejection was greater for FCXM positive vs. FCXM negative patients (51 vs. 21%, p=0.001). In contrast, with Regimen II the incidence of rejection for FCXM positive and FCXM negative patients was equivalent (18 vs. 12%, p=ns) and lower than patients treated with Regimen I (p < 0.01). Ethnic variation was only observed with Regimen I in which African Americans with positive FCXM had more rejections than Caucasians (60 vs. 45%, p < 0.05). Five-year actuarial survival was lower for FCXM positive vs. FCXM negative patients treated with Regimen I (40 vs. 75%, p=0.0006) or Regimen 2 (60 vs. 90%, p=0.001). Allograft survival was equivalent (p=ns) among FCXM positive individuals receiving Regimen I or II. However, allograft survival among FCXM negative individuals improved with Regimen II (p < 0.05). Ethnic variation in survival was not observed with either regimen (p=ns). 相似文献
926.
Morphological and functional characterization of a rat vaginal smooth muscle sphincter 总被引:3,自引:0,他引:3
Giraldi A Alm P Werkström V Myllymäki L Wagner G Andersson KE 《International journal of impotence research》2002,14(4):271-282
The aim of the present study was to gain information about adrenergic-, cholinergic- and non-adrenergic, non-cholinergic (NANC)- transmitter systems/mediators in the rat vagina, and to characterize its smooth muscles functionally. Tissue sections from vagina of Sprague Dawley rats were immunolabelled with antibodies against protein gene product 9.5 (PGP), synaptophysin (Syn), tyrosine hydroxylase (TH), vesicular acetylcholine transporter (VAChT), neuropeptide Y (NPY), nitric oxide synthase (NOS), vasoactive intestinal polypeptide (VIP), calcitonin gene-related peptide (CGRP) and pituitary adenylate cyclase-activating polypeptide (PACAP). Circularly cut vaginal smooth muscle preparations from the distal vagina were studied in organ baths. In the paravaginal tissue, a large number of PGP-, NOS-, TH-, VIP-immunoreactive (IR) and few CGRP-IR nerve trunks were observed, giving off branches to the smooth muscle wall. The smooth muscle wall was supplied by a large number of PGP-, Syn-, VAChT-, NPY-, NOS- and TH- IR nerve terminals, whilst only a moderate to few numbers of CGRP-, VIP- and PACAP-IR terminals were identified. Especially the distal part of the vaginal wall, where the circularly running smooth muscle was thickened into a distinct sphincter structure, was very richly innervated, predominantly by PGP- and NOS-IR terminals. Below and within the basal parts of the epithelium in the distal half of the vagina, a large number of PGP- and few NOS- and PACAP-IR varicose terminals were observed. The vaginal arteries were encircled by plexuses of nerve terminals. A large number of these were PGP-, Syn-, VAChT-, NOS-, TH-, NPY- and VIP-IR, and few were CGRP- and PACAP-IR. In isolated preparations of the distal vagina, electrical field stimulation (EFS) caused frequency-dependent contractions, which were reduced by sildenafil, tetrodotoxin (TTX) and phentolamine. In preparations contracted by norepinephrine (NA), EFS produced frequency-dependent relaxations. Pretreatment with the NOS-inhibitor N(G)-nitro-L-arginine, TTX, or the inhibitor of soluble guanylate cyclase, ODQ, abolished the EFS relaxations. In NE precontracted preparations, cumulative addition of sildenafil caused concentration-dependent relaxation. Carbachol contracted the strips concentration-dependently from baseline. It can be concluded that the distal part of the rat vagina forms a distinct smooth muscle sphincter, which is richly innervated by adrenergic, cholinergic and NANC nerves. The present studies suggest that in the rat the L-arginine/NO-system not only plays an important role in the regulation of vaginal smooth muscle tone, but also affects blood flow, and may have sensory functions. 相似文献
927.
928.
Wagner KD 《Psychopharmacology bulletin》2002,36(1):130-142
Psychostimulants are the first-line treatment for attention-deficit/hyperactivity disorder (ADHD) in children and adolescents. A minimum of two psychostimulant trials should be instituted before a child's symptoms of ADHD are considered treatment refractory. Clinical issues of diagnostic accuracy, comorbid disorders, psychosocial factors, medication compliance, symptoms across settings, and behavioral treatment should be addressed before initiating alternative medication trials. With the exception of tricyclic antidepressants, there is a paucity of controlled studies with adequate sample size to support the efficacy and safety of nonstimulant medications for the treatment of childhood ADHD. In this article, data on medications for treatment refractory ADHD in children and adolescents are presented and treatment strategies are discussed. 相似文献
929.
930.
OBJECTIVE: Several investigators have questioned the validity of the DSM-IV Alcohol Use Disorders criteria for diagnosing alcohol use problems among teenagers, with specific concerns about their utility across different subgroups. In the current study, we examined whether particular racial/ethnic or gender subgroups varied in the incidence and onset age of Alcohol Use Disorder symptoms. METHOD: Members of a sample composed of 1,045 community-dwelling "drinkers" (59.4% male; 13.8% black, 21.2% foreign-born Hispanic, 30.7% U.S.-born Hispanic and 33.6% non-Hispanic white) were interviewed retrospectively using the Composite International Diagnostic Interview. The first occurrence of each DSM-IV symptom in a participant was examined by race/ethnicity and gender. Discrete-time event history analysis compared onset patterns from ages 14 through 20 years. RESULTS: The cumulative incidence of Alcohol Abuse and Alcohol Dependence diagnoses, as well as one alcohol abuse symptom and four dependence symptoms, varied by race/ethnicity. The incidence of both diagnoses, as well as two alcohol abuse symptoms, varied by gender. Event history analysis revealed no significant subgroup variation in first onset patterns for only three of the eleven symptoms. Racial/ethnic variation, but not gender variation, was significant for three symptoms, and both racial/ethnic variation and gender variation was significant for the remaining five symptoms. CONCLUSIONS: Our findings indicate that most of the DSM-IV Alcohol Use Disorder symptoms, when applied to adolescents, demonstrate significant subgroup variation in incidence and onset age patterns. These results speak to the urgent need for additional research concerning the nosology and diagnosis of alcohol use problems among younger drinkers, especially among specific racial/ethnic and gender subgroups. 相似文献