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981.
The course of the subscapular artery was studied in 20 rabbits. Its course was constant, giving two branches to the latissimus dorsi muscle after which the vessel sent a branch (S1) that perforated the panniculus carnosus to supply a large territory of skin. In a separate experiment, the contribution of the S1 branch to the viability of the rabbit latissimus dorsi musculocutaneous flap was evaluated. From this experiment it can be concluded that, first, it is possible in a rabbit to elevate a large skin flap based solely on a muscle perforator (S1), which survives completely. Second, in the rabbit latissimus dorsi musculocutaneous flap, S1 is the major blood supply to the skin component. Damage to it severely diminishes skin flap survival, even if the vascular supply to the underlying muscle is completely intact.  相似文献   
982.
Summary The paucity of information on the effect of long-term high-dose salmon calcitonin administration on normal bone mineral metabolism and histology prompted an investigation of the influence of high-dose synthetic calcitonin in the rat. Serum ionized calcium, osteocalcin or BGP (bone gla protein), and immunoreactive PTH were measured serially during calcitonin administration and bone histomorphometry analyzed at 6 weeks (after sacrifice). Daily injections of salmon calcitonin, 0.4 IU/100 g (group B) and 2 IU/100 g (group C), resulted in significant hypocalcemia at 4 hours for both experimental groups (P<0.004). Serium iPTH was significantly higher over the study period for both groups administered calcitonin. Serum BGP levels were significantly lower than controls during the study in group C (P<0.002) and to a lesser extent in group B (P<0.05). In group C, bone histomorphometry revealed increased resorption (onteoclast count), decreased trabecular bone volume, and decreased double-labeled tetracycline surface (bone formation). In group B an increase in osteoclast count but no alteration in bone formation was observed. To assess the role of PTH in the above findings, high-dose calcitonin was administered to parathyroidectomized rats. All of the above changes in bone histomorphometry were not observed in this group of animals. In conclusion, high doses of calcitonin promote hypocalcemia, secondary hyperparathyroidism, and osteoclastosis in the normal rat in a dose-dependent manner with very high-dose calcitonin impairing bone formation.  相似文献   
983.
Schultz metacarpophalangeal arthroplasty: a long-term follow-up study   总被引:1,自引:0,他引:1  
We describe a prospective, long-term evaluation of the Schultz metacarpophalangeal joint implant. The prosthesis is a semiconstrained, cemented implant with a ball-in-socket articulation. Thirty-six implants were followed for an average of 10.9 years. There was a progressive decrease in range of motion and strength and a recurrence of ulnar deviation. The neck of the proximal phalangeal component fractured in 39% of the joints. Periarticular heterotopic bone formed in all joints, but was extensive in only 22%. Although some lucency of the bone-cement interface was seen in 80% of the joints, no prosthetic loosening occurred in this series. Our results indicate that long-term, intramedullary cement fixation of relatively long-stemmed components can be satisfactory. However, the articulated portion of this implant does not consistently withstand the stresses transmitted across the joint and does not provide long-term joint stability.  相似文献   
984.
Twenty-seven patients underwent syringe-assisted liposuction of the neck, the amount of fat removed ranging from 20-110 ml. There were no complications except slight skin laxity (n = 1) and transient hypoaesthesia (n = 10). No patient required a second procedure, and all were satisfied with the results. Syringe-assisted microlipoextraction of cervical fat is a simple, safe, and rewarding procedure that has obvious advantages over open procedures or machine-assisted liposuction with large cannulas.  相似文献   
985.
The experience acquired over the last four years in developing a program of cooperation in mental health in Nicaragua is reported. The concept of 'transfer' underlying the intervention and the general framework of Nicaragua's mental health system is discussed together with the results of the cooperative work. This included organizing training for mental health workers in six teaching and supervision modules, drawing up a mental health manual for primary health care workers, and survey of patterns of care in the 15 existing psychiatric services. Besides the key aspects of general reform of the psychiatric system after the revolution, the paper focuses on differences between organization and patterns of care in urban and rural areas.  相似文献   
986.
Consecutive new attendees at a rheumatology clinic were randomlyallocated to one of three groups. All groups received routinecare, but one received no other intervention, one an educationalbooklet on arthritis and one the booklet plus instruction froma health professional. Prior to intervention, all groups hadsimilar knowledge, Nottingham Health Profile (NHP) and HealthAssessment Questionnaire (HAQ) score. After 6 weeks, the knowledgescore was significantly increased in both groups given the booklet,but not in the control group. The group instructed by a healthprofessional showed no greater increase than the group giventhe booklet alone. Increased knowledge was not associated withimproved clinical status and no group showed a significant'change in NHP or HAQ scores. Nearly all patients said they foundthe booklet useful. KEY WORDS: Randomized controlled trial, Evaluation, Patient education, Booklet, Knowledge, Arthritis  相似文献   
987.
Abstract: It has been hypothesized that pineal structure and function might differ between temperate zone and tropical species of mammals because of lower amplitudes of seasonal change in photoperiod and, in some areas, less seasonal climatic variation. Anoura geoffroyi produce a single offspring in November or December of each year on the Caribbean island of Trinidad, at 10°N latitude in the deep tropics. Previous work has shown that this population lacks reproductive responses to photoperiod, and must be enforcing seasonal breeding using a non-photoperiodic cue. Anoura geoffroyi have a minute, thin, and rod-like pineal gland. Throughout much of its length, the pineal courses irregularly within the ventrolateral wall of the great cerebral vein. This intimate relationship may have functional implications. Despite having a very small pineal gland, this species produced a nocturnal rise in serum melatonin. Serum melatonin levels in most individuals were below or near undetectable levels during the light period and rose to a peak averaging 100 pg/ml in the last third of the dark period. Our results indicate that, although the pineal gland of A. geoffroyi is extremely small, serum melatonin levels are comparable to those of other mammals.  相似文献   
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