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101.
Nicholas Henschke Christopher G Maher Kathryn M Refshauge Robert D Herbert Robert G Cumming Jane Bleasel John York Anurina Das James H McAuley 《BMC musculoskeletal disorders》2006,7(1):54-5
Background
Clinical guidelines generally portray acute low back pain as a benign and self-limiting condition. However, evidence about the clinical course of acute low back pain is contradictory and the risk of subsequently developing chronic low back pain remains uncertain. There are few high quality prognosis studies and none that have measured pain, disability and return to work over a 12 month period. This study aims to provide the first estimates of the one year prognosis of acute low back pain (pain of less than 2 weeks duration) in patients consulting primary care practitioners. A secondary aim is to identify factors that are associated with the prognosis of low back pain. 相似文献102.
Clustering of mutations in the biotin-binding region of holocarboxylase synthetase in biotin-responsive multiple carboxylase deficiency 总被引:4,自引:2,他引:2
Dupuis L; Leon-Del-Rio A; Leclerc D; Campeau E; Sweetman L; Saudubray JM; Herman G; Gibson KM; Gravel RA 《Human molecular genetics》1996,5(7):1011-1016
Holocarboxylase synthetase (HCS) catalyses the biotinylation of the four
biotin-dependent carboxylases found in humans. A deficiency in HCS results
in biotin-responsive multiple carboxylase deficiency (MCD). We have
identified six different point mutations in the HCS gene in nine patients
with MCD. Two of the mutations are frequent among the MCD patients
analyzed. Four of the mutations cluster in the putative biotin- binding
domain as deduced from the corresponding Escherichia coli enzyme and
consistent with an explanation for biotin-responsiveness based on altered
affinity for biotin. The two others may define an additional domain
involved in biotin-binding or biotin-mediated stabilization of the protein.
相似文献
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106.
Kathryn M. Refshauge S. L. Kilbreath S. C. Gandevia 《Experimental brain research. Experimentelle Hirnforschung. Expérimentation cérébrale》1998,122(1):85-92
To determine whether proprioceptive acuity is the same at all digits, particularly when postured as in a ’grasp’, we imposed
10° movements at the distal joint of the thumb, index and ring finger, at three velocities; 1.25°/s, 2.5°/s and 5°/s. The
test joint was initially flexed by 25° and the joints proximal to the test joint were maintained in a standard posture for
each study. When in a grasp posture that disengaged the extensor muscles at the distal joint of the finger, movement detection
at the thumb was superior to that at the fingers for all velocities. However, when the fingers were positioned so that all
proprioceptive inputs were able to contribute (i.e. cutaneous, joint and both flexor and extensor muscle afferents), proprioceptive
acuity was similar for the three digits. Loss of local cutaneous (and joint) inputs by digital anaesthesia significantly impaired
performance at all digits, suggesting a critical role for cutaneous input in normal proprioceptive sensibility at all distal
joints of the digits. Anaesthesia of the extensor muscle afferents innervating the thumb did not affect its proprioceptive
acuity. Thus, for the thumb, the extensor muscle afferents do not provide critical information. The greater change in muscle
fascicle length for the thumb’s long flexor muscle (3% per 10°) compared with that in the finger flexor muscles (e.g. 0.1%
per 10°) could contribute to the thumb’s performance. There appears to be less redundancy of muscle and non-muscle signals
for the fingers than for the thumb, because a reduction in either cutaneous or muscle input significantly impaired acuity
at the fingers. Overall, when the hand is in a grasping posture, irrespective of the contribution of local cutaneous inputs,
the long flexor acting on the thumb may contribute more to its proprioceptive acuity than the long finger flexors contribute
to acuity at the fingers.
Received: 20 January 1998 / Accepted:25 March 1998 相似文献
107.
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109.
Platelet adhesion to collagen types I through VIII under conditions of stasis and flow is mediated by GPIa/IIa (alpha 2 beta 1-integrin) 总被引:13,自引:6,他引:7
Saelman EU; Nieuwenhuis HK; Hese KM; de Groot PG; Heijnen HF; Sage EH; Williams S; McKeown L; Gralnick HR; Sixma JJ 《Blood》1994,83(5):1244-1250
Platelet adhesion to fibrillar collagens (types I, II, III, and V) and nonfibrillar collagens (types IV, VI, VII, and VIII) was investigated in the presence of physiologic concentrations of divalent cations under conditions of stasis and flow. Under static conditions, platelet adhesion was observed to collagen types I through VII but not to type VIII. Under flow conditions, platelet adhesion to collagen types I, II, III, and IV was almost independent of shear rates above 300/s. Collagen type V was nonadhesive. Platelet adhesion to collagen type VI was shear rate-dependent and optimal at a rate of 300/s. Collagen types VII and VIII showed minor reactivity and supported platelet adhesion only between shear rates 100 to 1,000/s. Monoclonal antibody (MoAb) 176D7, directed against platelet membrane glycoprotein Ia (GPIa; very late antigen [VLA]-alpha 2 subunit), completely inhibited platelet adhesion to all collagens tested, under conditions of both stasis and flow. Platelet adhesion to collagen type III at shear rate 1,600/s was only inhibited for 85%. The concentration of antibody required for complete inhibition of platelet adhesion was dependent on the shear rate and the reactivity of the collagen. An MoAb directed against GPIIa (VLA-beta subunit) partially inhibited platelet adhesion to collagen. These results show that GPIa-IIa is a major and universal platelet receptor for eight unique types of collagen. 相似文献
110.
Pseudoaneurysms complicating organ transplantation: roles of CT, duplex sonography, and angiography 总被引:2,自引:0,他引:2
Tobben PJ; Zajko AB; Sumkin JH; Bowen A; Fuhrman CR; Skolnick ML; Bron KM; Esquivel CO; Starzl TE 《Radiology》1988,169(1):65-70
In a retrospective study of proved pseudoaneurysms (PAs) in 15 patients with transplanted organs (11 liver, three kidney, one pancreas), the results of computed tomography (CT), duplex sonography, and angiography were reviewed. Of the 15 cases of PA, eight occurred at the arterial anastomosis and seven were nonanastomotic. Three of the eight anastomotic PAs were caused by infection. Of the seven nonanastomotic PAs, four were caused by percutaneous biopsy, two were caused by infection, and one was of undetermined cause. In nine (60%) of the 15 patients the PAs were incidentally detected at imaging studies performed for other reasons. Diagnosis requires a high degree of suspicion. CT was performed in nine cases and duplex sonography in ten. The diagnosis of PA was made with CT in six (67%) patients and with duplex sonography in five (50%). CT and duplex sonography could not enable diagnosis when the PA was small, when the arterial anastomosis was not included in the field of study, or when enhancement with intravenously administered contract material was suboptimal. Angiography depicted the PAs in all 15 patients. In three liver transplant recipients with gastrointestinal tract bleeding, the causative PAs were detected only with angiography. 相似文献