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91.
Falla D Farina D Graven-Nielsen T 《Experimental brain research. Experimentelle Hirnforschung. Expérimentation cérébrale》2007,178(3):385-393
The aim of the study was to examine the effect of experimental unilateral upper trapezius muscle pain on the relative activation
of trapezius muscle subdivisions bilaterally during repetitive movement of the upper limb. Surface EMG signals were detected
from nine healthy subjects from the upper, middle and lower divisions of trapezius during a repetitive bilateral shoulder
flexion task. Measurements were performed before and after injection of 0.5 ml hypertonic (pain condition) and isotonic (control)
saline into the upper division of the right trapezius muscle in two experimental sessions. On the painful side, upper trapezius
showed decreased EMG amplitude (average rectified value, ARV) and lower trapezius increased ARV throughout the entire task
following the injection of hypertonic saline (40.0 ± 22.2 vs. 26.0 ± 17.4 μV, and 12.5 ± 7.6 vs. 25.6 ± 14.8 μV, respectively,
at the beginning of the contraction). On the side contralateral to pain, greater estimates of ARV were identified for the
upper division of trapezius as the task progressed (37.4 ± 20.2 vs. 52.7 ± 28.4 μV, at the end of the contraction). Muscle
fiber conduction velocity did not change with pain in all three divisions of the right trapezius muscle. The results suggest
that local elicitation of nociceptive afferents in the upper division of the trapezius induces reorganization in the coordinated
activity of the three subdivisions of the trapezius in repetitive dynamic tasks. 相似文献
92.
Ning Jiang Silvia Muceli Bernhard Graimann Dario Farina 《Medical & biological engineering & computing》2013,51(1-2):143-151
Myoelectric control has been extensively applied in multi-function hand/wrist prostheses. The performance of this type of control is however, influenced by several practical factors that still limit its clinical applicability. One of these factors is the change in arm posture during the daily use of prostheses. In this study, we investigate the effect of arm position on the performance of a simultaneous and proportional myoelectric control algorithm, both on trans-radial amputees and able-bodied subjects. The results showed that changing arm position adversely influences the performance of the algorithm for both subject groups, but that this influence is less pronounced in amputee subjects with respect to able-bodied subjects. Thus, the impact of arm posture on myoelectric control cannot be inferred from results on able-bodied subjects and should be directly investigated in amputee subjects. 相似文献
93.
To determine the growth pattern and in vitro susceptibility of Blastocystis hominis to metronidazole (MTZ), garlic, ginger, white cumin, and black pepper. Stool specimens were collected from 16 irritable bowel
syndrome (IBS) and 10 controls between July–November 2010. Stool microscopy and culture for B. hominis was performed. Drug susceptibility assays was done using 0.01 and 0.1 mg/ml of MTZ, garlic, ginger, white cumin, and black
pepper. Effect was assessed on B. hominis culture after 48 h. Stool DNA was extracted using stool DNA extraction kit (Qiagen) and polymerase chain reaction (PCR) done
using subtype-specific sequence-tagged-site primers. B. hominis genotype 3 and coinfection of 1 and 3 tended to grow well in culture compared to isolated type 1 infection. Exposed to MTZ
at a concentration of 0.01 mg/ml, 38% (6/16) B. hominis from IBS did not grow in culture compared to 100% (10/10) of B. hominis from control (p = 0.001). When they were exposed to MTZ at 0.1 mg/ml, 56% (9/16) B. hominis from IBS did not grow in cultures compared to 100% (10/10) from control (p = 0.01). Forty-four percent (7/16) B. hominis from IBS did not grow in culture compared to 100% (10/10) B. hominis from control when exposed to garlic at a concentration of 0.01 mg/ml (p = 0.003) and following exposure to garlic at 0.1 mg/ml, 38% (6/16) B. hominis from IBS did not grow in cultures compared to 100% (10/10) from control (p = 0.001). B. hominis isolates from IBS had a cell count of 6,625 at a MTZ concentration of 0.01 mg/ml that reduced to 1,250 as MTZ concentration
was increased to 0.1 mg/ml (p = 0.08). B. hominis from IBS with a mean cell count of 3 × 105 at baseline decreased to 1 × 104 when exposed to garlic at 0.01 mg/ml (p < 0.001) and to 1 × 103 (p < 0.001) when garlic was 0.1 mg/ml. B. hominis from IBS cell count decreased to 1 × 105 when exposed to white cumin at 0.01 mg/ml (p = 0.01) and to 1 × 105 (p < 0.001) when white cumin was 0.1 mg/ml. Exposed to black pepper at 0.1 mg/ml, cell count of B. hominis from IBS decreased to 1 × 105 (p = 0.01). B. hominis from IBS decreased to 1.3 × 105 exposed to ginger at 0.01 mg/ml (p = 0.001). B. hominis isolates were mostly genotypes 3, type 1 and 3 coinfection, and non-typeable B. hominis isolates. B. hominis isolates from IBS mostly genotype 1 demonstrated an increased sensitivity to garlic at 0.01 mg/ml with a B. hominis cell count of 3,714 compared to 6,142 when exposed to 0.01 mg/ml of MTZ. However, this sensitivity did not increase as garlic
concentration was increased to 0.1 mg/ml, for B. hominis cell count was 6,000 compared to 1,428 as MTZ was increased to 0.1 mg/ml. 相似文献
94.
The detection in human sera of antisperm antibodies reactive with FA-1, an evolutionarily conserved antigen, and with murine spermatozoa 总被引:2,自引:0,他引:2
R A Bronson G W Cooper E J Margalioth R K Naz M S Hamilton 《Fertility and sterility》1989,52(3):457-462
Evolutionarily conserved antigens are present on spermatozoa of several mammalian species. We tested sera from infertile men and women containing antisperm antibodies (ASAs) for their reactivity with FA-1, an antigen known to be present on murine and human spermatozoa. Fifty percent of male sera and 63% of female sera contained anti-FA-1 antibodies, as judged by enzyme linked immunosorbent assay (ELISA). Fourteen percent of male sera and 50% of female sera were also shown to possess ASAs reactive with living mouse spermatozoa, and murine in vitro fertilization was inhibited by human antibodies. These results suggest that the transfer of immunoglobulins from human sera to spermatozoa of other species may provide a model to study how ASAs effect sperm function. 相似文献
95.
Effects of antibodies to sperm surface fertilization antigen-1 on human sperm-zona pellucida interaction. 总被引:3,自引:0,他引:3
OBJECTIVE: To investigate the effects of antibodies to well-defined sperm surface antigens (the fertilization antigen [FA-1] and germ-cell antigen [GA-1]) and nuclear antigen (protamine) on human sperm-zona interaction. DESIGN: Number of total and acrosome-reacted human sperm bound to the human zona pellucida and the sperm movement characteristics assessed by computer-aided sperm analysis were evaluated after incubation of sperm with the antibodies. SETTING: Academic research environment approved by the Institute Review Board. PATIENTS: Human oocytes were obtained from ovaries removed at surgery. Semen from fertile donors was used in all assays. INTERVENTIONS: Human oocytes were stored in salt solution at -80 degrees C until used. Spermatozoa were treated with the antibodies to various sperm antigens. MAIN OUTCOME MEASURES: Total and acrosome-reacted sperm bound to zona pellucida and sperm movement characteristics were evaluated after 3 to 5 hours of incubation of the antibodies with human sperm. RESULTS: Anti-FA-1 antibodies significantly reduced human sperm fusion with zona-free hamster oocytes and sperm binding to the human zona pellucida but did not affect binding of acrosome-reacted sperm and sperm movement characteristics. Anti-GA-1 and antiprotamine antibodies did not affect sperm-oocyte interaction, acrosomal reaction, or sperm motility. CONCLUSIONS: Antibodies to FA-1 but not to GA-1 and protamine inhibit human sperm-zona interaction. 相似文献
96.
Rajesh K. Naz Burt A. Littman Robert J. Stillman 《Journal of assisted reproduction and genetics》1985,2(3):143-145
Frozen-thawed husband's semen was utilized for insemination of spouse's oocytes in vitro. Postthhaw semen had a low motility (40%) with a poor forward progression (+2), which subsequently decreased rapidly in the regalarly used Ham's F-10 medium (pH 7.42, 280 mosmoll kg) supplemented with 7.5% fetal cord serum. When Fam's F-10 was supplemented with an additional 0.5 mmol each of magnesium sulfate (MgSO4) and potassium bicarbonate (KHCO3) at a higher pH (pH 7.69, 280 mosmol/kg), the sperm maintained their motility and forword progression and fertilized all the oocytes, which subsequently cleaved and developed into normal embryos. Transfer of therse embryos resulted in a normal pregnancy. Our results indicate that cryopreserved semen of poor quality can be successfully employed for an in vitro fertilization-embryo transfer (IVF-ET) program, especially when MgSO4 and KHCO3 are used in Ham's F-10 at a higher pH. 相似文献
97.
A case of fetal pleural effusion detected by ultrasound at 33 weeks of gestation is described. 相似文献
98.
Selective inhibition of osteoclast vacuolar H(+)-ATPase 总被引:3,自引:0,他引:3
The proton pump expressed on the plasma membrane of bone resorbing osteoclasts, and which mediates the acidification of the extracellular environment in resorption lacuna, belongs to the family of vacuolar H(+)-ATPases, which are enzymes ubiquitously distributed among all cells and are evolutionary conserved. These pumps have two functional domains: a peripherally associated cytoplasmatic section, and a proton channel composed of several subunits one of which, the 116 kDa subunit, is expressed exclusively in osteoclasts and confers unique functional and pharmacological properties to the osteoclast V-ATPase. It was demonstrated that inhibition of this pump can abolish bone resorption; therefore, osteoclast-selective inhibitors could provide novel and useful agents for the treatment of osteoporosis. This paper reviews the medicinal chemistry approaches that have allowed to obtain such new agents, most of which have been designed starting from the natural macrolide antibiotic bafilomycin A(1), a potent and selective inhibitor of all V-ATPases. Identification of SAR and of minimal structural requirements for bafilomycin activity have allowed to obtain (2Z,4E)-5-(5,6-dichloroindolyl)-2-methoxy-N-(1,2,2,6,6-pentamethylpiperidin-4-yl)-2,4-pentadienamide (SB-242784) which inhibits the osteoclastic proton pump and bone resorption in vitro. Although it inhibits the activity of non-osteoclastic proton pumps as well, it appears to have reasonable selectivity and its administration for 6 months prevented the loss of femoral and vertebral BMD in ovariectomized rats, without any significant renal effects in control and acid-loaded animals. Other independent approaches that did not start from bafilomycin have led to the discovery of a different class of V-ATPase inhibitors, among which 4-(2,6-dichlorobenzoyl)amino-2-trifluoromethyl(benzoimidazol-1-yl)acetyl morpholine (FR177995) was the most effective in preventing bone resorption in an ovariectomized rat model of osteoporosis. These compounds are of great pharmaceutical and medical interest because they allow to target a specific function of the osteoclast; however, only clinical trials might demonstrate whether they have significant advantages over other inhibitors of bone resorption for the treatment of osteoporosis. 相似文献
99.
Iaia TE Bartoli D Calzoni P Comba P De Santis M Dini F Ercolanelli M Farina GA Pirastu R Seniori Costantini A Valiani M 《La Medicina del lavoro》2002,93(2):95-107
BACKGROUND: Epidemiological studies of tanners have shown increased risk for a number of cancer sites, namely: lung, bladder, kidney and urinary organs as well as stomach, intestine, pancreas, nose and nasal cavities, together with leukemias and soft tissue sarcomas. OBJECTIVE: To study cause specific mortality of leather tanners in Tuscany (Valdarno Inferiore area). METHODS: The cohort included 4874 workers (4150 males and 724 females) employed in 92 tanneries operating in 1996 (Valdarno Inferiore Tanneries Census) which were also operating on 31-12-1970. Ascertainment of vital status was completed for all individuals on 31-12-1998 (end of follow-up), and the cause of death was known for all deceased subjects. Demographic and work history data were obtained from factory payrolls. Regional mortality rates were used for comparison to calculate SMR (Standardised Mortality Ratio) and 90% Confidence Intervals (CI). In addition to the overall cohort analysis, for men only separate analyses were completed for finishers, chrome tanners and vegetable tanners. RESULTS: The study showed an increased mortality from lung cancer among finishers, Standardised Mortality Ratio (SMR) 145, 19 observed (obs) (90% Confidence Intervals, 90% CI 95-212), from bladder cancer in the overall cohort (SMR 134, 9 obs, 90% CI 70-233) and among finishers (SMR 125, 2 obs, 90% CI 22-393) and from pancreatic cancer among finishers (SMR 120, 2 obs, 90% CI 21-379). Mortality from lymphoemopoietic cancer is above expected, and the increase is mainly due to myeloid leukaemia, both in males (SMR 208, 5 obs, 90% CI 82-437) and females (SMR 599, 2 obs, 90% CI 106-1887). No deaths from soft tissue sarcoma were observed. A new finding of the study was the increased mortality from cancer of the endocrine glands (SMR 566, 4 obs, 90% CI 194-1297), psychiatric disorders (SMR 195, 6 obs, 90% CI 85-385) and blood diseases (SMR 329, 4 obs, IC 90% 112-752). CONCLUSIONS: The observations of increased lung cancer mortality among finishers, of bladder cancer in the overall cohort and among finishers, as well as an increase in pancreatic cancer among the latter, confirm previous epidemiological findings among tanners. The increase in myeloid leukemia mortality for both males and females, and the absence of deaths from cancer of the connective tissue, which includes soft tissue sarcomas, are worthy of note. The results should be valued with caution, given the small number of cases and the novelty of some observations. 相似文献
100.