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1.
The objective of this review is to identify and review publications describing the impact of reduced somatosensation on balance. Based on knowledge of the association between specific somatosensory loss and deterioration of balance, conclusions can be made about role of somatosensation in standing balance.A systematic literature review is presented in which publications from the years 1993 through 2007 were searched in Medline and Embase. Medical Subject Headings (MESH) terms and free text words (related to balance, somatosensory loss, and lower limb) were used to perform the searches. Fifteen articles were selected for detailed review based on predetermined inclusion criteria, and three of the included articles described the effect of experimentally reduced somatosensation on balance in healthy subjects. Ten of the articles described balance in diabetic neuropathy (DN). The last two included articles described balance in Charcot-Marie-Tooth (CMT) disease type 1A (CMT1A) or type 2 (CMT2).The literature indicates that the tactile sensation is reduced in DN, CMT1A, and CMT2 and when the plantar surface of the feet was hypothermically anesthetized. Joint motion sensation seems to be impaired in patients with DN, and passive joint position sensation appears to be reduced in healthy subjects with anesthesia of ankle and foot from prolonged ischemia. This reduced somatosensation seems to have a negative effect on balance in patients with DN and CMT2; however, this appeared not to be the case in patients with CMT1A and in healthy subjects.  相似文献   
2.
Evidence of the effect of exercise on bone loss comes mainly from studies in voluntary postmenopausal women, and no population-based, long-term interventions have been performed. The purpose of this population-based, randomized, controlled trial was to determine the effect of long-term impact exercise on bone mass at various skeletal sites in elderly women with low bone mineral density (BMD) at the radius and hip. Participants ( n =160) were randomly assigned to 30 months either of supervised and home-based impact exercise training or of no intervention. The primary outcome measures were femoral neck, trochanter and total hip BMD, and the secondary outcomes were bone density measures at the radius and calcaneum. Outcomes were assessed at baseline, 12 months and 30 months using blinded operators. The analyses were performed on an intention-to-treat analysis. Mean femoral neck and trochanter BMD decreased in the control group [–1.1%, 95% confidence interval (CI) –0.1% to –2.1% and –1.6%, 95% CI –0.4% to –2.7%], while no change occurred in the exercise group. Mean trochanter BMC decreased more in the control group (–7.7%, 95% CI –9.7% to –5.6% vs. –2.9%, 95% CI –5.3 to –0.9). There were six falls that resulted in fractures in the exercise group and 16 in the control group during the 30-month intervention ( P =0.019). A significant bone loss occurred in both groups at the radius and calcaneum. In multivariate analysis, weight gain was associated with increased BMD and BMC at all femur sites both in the exercise group and in the pooled groups. In conclusion, impact exercise had no effect on BMD, while there was a positive effect on BMC at the trochanter. Exercise may prevent fall-related fractures in elderly women with low bone mass.There was no conflict of interest.  相似文献   
3.
Since we introduced angioscopy in autumn 1991 byin situ vein bypass operations we have used four different angioscopes with outer diameters of 2.2, 2.3, 2.8, and 2.9 mm. The 2.2 mm model was steerable, and collateral irrigation through a separate irrigation catheter was used. The other scopes had a built-in irrigation channel. Irrigation fluid was provided by a pressure cuff device placed around a liter of Ringer's acetate solution in plastic bag and inflated to between 200 and 300 mmHg. Recently we have used a roller pump that provides adjustment of the flow rate with a constant pressure of 200 mmHg. A Mills valve cutter was tested in the initial phase, but later the Insitucath proved more suitable. Valve disruption has been safe and confident. In addition, the angioscopy has been used as an adjuvant method in carotid endartectomies, thromboembolectomies, aortobifemoral reconstructions, iliacofemoral endarterectomies, in vascular access surgery, and percutaneous stent application. The visualization has been excellent or good and there have not been any significant complications due to the angioscopes. The use of angioscopy is well established in our arterial procedures and in the near future it will be introduced in venous surgery. The need for further studies concerning the significance of intraluminal findings is obvious.Presented at the 35th World Congress, International College of Angiology, Copenhagen, Denmark, July 1993  相似文献   
4.
Objective: To study tubal patency and fertility outcome of patients with expectantly managed ectopic pregnancy (EP).

Design: A prospective study.

Setting: Department of Obstetrics and Gynecology, Turku University Central Hospital, Turku, Finland.

Patient(s): Thirty patients who wanted to become pregnant again were treated successfully by expectant management of EP.

Intervention(s): Patients were examined with posttreatment hysterosalpingography, and they filled out a questionnaire about their subsequent pregnancies.

Main Outcome Measure(s): Free passage through open lumen showing tubal patency; number of full-term pregnancies and EPs revealing relative rate of subsequent fertility.

Result(s): A free passage through the diseased tube was seen in 93% of the cases (28 of 30). Two of the 24 patients (8.4%) who wanted to become pregnant had an obstruction in the diseased tube. One (4.2%) of them had a normal opposite tube and later had a normal pregnancy. The other (4.2%) had an obstruction in both tubes and subsequently had a repeat EP. One of the 6 patients had an EP (this patient did not want to become pregnant and did not use contraception). However, her posttreatment hysterosalpingography was normal. In total, the subsequent pregnancy rate was 88% (21 of 24), and the rate of repeat EP was 4.2% (1 of 24).

Conclusion(s): Patients who are treated with expectant management have a good long-term fertility outcome. Spontaneous regression of EP does not lead to increased harm or damage to the tube, i.e., the risk for repeat EP is low.  相似文献   

5.
Summary It has been widely observed that the outcome after repeat lumbar surgery is rarely comparable to that of primary surgery. In particular, the results of repeat surgery for lumbar spinal stenosis (LSS) have not been favourable. We used a matched-pair format in an attempt to decrease the confounding factors so as to determine as exactly as possible the effect of prior back surgery on the LSS patients surgical outcome. The matching criteria were sex, age, myelographic findings, major symptom, and duration of symptoms. From one group of 251 patients without prior back surgery (SO patients) and another of fifty-three patients with one preceding back operation (RS patients), forty-one similar matched patients pairs (one SO and one RS-patient) were formed.There were 8 female and 33 male pairs. The mean age of the SO patients was 51.6 and of the RS patient 51.4 years, and the mean follow-up time was 4.6 and 4.4 years. The assessment of outcome was based on a subjective disability questionnaire. The SO patients fared significantly better than the RS patients (32.1 versus 41.3, P = 0.026). A short time interval between operations in the RS patients had a worsening effect on outcome, but this trend was not significant.We concluded that one preceding back operation had a worsening effect on the outcome of patients operated on for LSS. As a whole, the results of RS patients were unfavourable. The proper time for achieving good surgical results in LSS patients is the initial operation.  相似文献   
6.
7.
Impaired vagal heart rate control in coronary artery disease.   总被引:1,自引:1,他引:0  
Heart rate variation in deep breathing, a sensitive non-invasive measure of cardiac parasympathetic activity, was measured in 63 patients with coronary artery disease, in 22 patients with atypical chest pain, and in 20 healthy symptom free volunteers. There was significantly less heart rate variation in deep breathing in the patients with coronary artery disease than in the healthy subjects. Twenty patients (32%) with coronary artery disease had lower than normal variation in heart rate. The patients with chest pain showed an intermediate heart rate response to deep breathing. Sinus arrhythmia in the patients with coronary artery disease was not related to the functional class, medication, number or location of narrowed vessels, or to the left ventricular ejection fraction, and end diastolic pressure. These results suggest that impairment of the parasympathetic nervous function is common in coronary artery disease.  相似文献   
8.

Background  

Movement control dysfunction [MCD] reduces active control of movements. Patients with MCD might form an important subgroup among patients with non specific low back pain. The diagnosis is based on the observation of active movements. Although widely used clinically, only a few studies have been performed to determine the test reliability. The aim of this study was to determine the inter- and intra-observer reliability of movement control dysfunction tests of the lumbar spine.  相似文献   
9.
Complement-Mediated Killing of Microtumors in Vitro   总被引:1,自引:0,他引:1       下载免费PDF全文
Complement-mediated lysis of cancer cells growing in three-dimensional aggregates involves factors that are not associated with the killing of cells in suspension. We have used multicellular tumor spheroids established from breast carcinoma (T47D) and ovarian teratocarcinoma (PA-1) cell lines as models to study complement-mediated destruction of micrometastases and small solid tumors. We found that significant killing of microtumors treated with an antitumor antibody and a specific monoclonal antibody (YTH53.1) against the complement lysis inhibitor protectin (CD59) started to occur after a 1 to 2-hour lag phase. After an overnight incubation, the microtumors became totally infiltrated by the YTH53.1 monoclonal antibody and C1q, whereas C3 and C5b-9 penetrated as a frontier to the peripheral cell layers. A 51Cr release assay showed that during a 24-hour pulsed treatment with complement, 33% of cells in the spheroids were killed, and the average tumor volume decreased by 28%. According to propidium iodide staining, complement exposure resulted in killing and peeling off of the outermost tumor cells.  相似文献   
10.
Bacteriophage PRD1 is an icosahedral dsDNA virus with a diameter of 740 A and an outer protein shell composed of 720 copies of major coat protein P3. Spike complexes at the vertices are composed of a pentameric base (protein P31) and a spike structure (proteins P5 and P2) where the N-terminal region of the trimeric P5 is associated with the base and the C-terminal region of P5 is associated with receptor-binding protein P2. The functionality of proteins P3 and P5 was investigated using insertions and deletions. It was observed that P3 did not tolerate changes whereas P5 tolerated changes much more freely. These properties support the hypothesis that viruses have core structures and functions, which remain stable over time, as well as other elements, responsible for host interactions, which are evolutionally more fluid. The insertional probe used was the apex of exposed loop 4 of group B meningococcal outer membrane protein PorA, a medically important subunit vaccine candidate. It was demonstrated that the epitope could be displayed on the virus surface as part of spike protein P5.  相似文献   
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