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1.
O. A. MIRGHANI† E. O. EL AMIN† M. E. S. ALI† H. S. OSMAN‡ B. HAMAD§ 《Medical education》1988,22(4):314-316
The community-based course presented is a longitudinal course running through four semesters in the Faculty of Medicine, University of Gezira, Sudan. Students combine their regular work in primary health care centres with attachments to a number of families in Wad Medani town. They continue to visit these families regularly throughout their entire medical course with the aim of studying them and helping them with some of their medical and psychosocial problems. 相似文献
2.
Abstract We previously demonstrated that cytomegalovirus (CMV) infection enhanced perivascular inflammation in rat aortic allografts. In this study, we investigated the relationship between the CMV infection load and the magnitude of perivasculitis (chronic rejection) in aortic transplants. Rats received or-thotopic abdominal aortic grafts, different degrees of total body irradiation (TBI) for immunosuppres-sion and CMV inoculation. The spleens of the rats receiving 5 Gy of TBI contained more infectious virus and viral antigens than those of rats receiving 3 Gy of TBI or no TBI. Although the number of inflammatory cells infiltrating the perivascular area was decreased after TBI, CMV infection resulted in increased perivasculitis in rats that received 5 Gy of TBI as compared to non-infected animals. This virus-induced effect was characterized predominantly by an increased T-cell infiltration, including CD4 and CD8 T-cells. It is concluded that an enhanced systemic CMV infection during severe immunosuppressive therapy can accelerate the development of chronic rejection, which seems to be mediated mainly by T-cells. 相似文献
3.
4.
Yasser EMAD Yasser RAGAB Ahmed EL‐MARAKBI Salama MOHAMED HANFI 《International journal of rheumatic diseases》2007,10(4):326-329
A 48‐year‐old male patient with long‐standing ulcerative colitis since February 2001 which was diagnosed by endoscopy, developed acute digital ischemia affecting both hands with fixed colour changes in the left index finger which was followed shortly by digital ulceration. Magnetic resonance angiography (MRA) of both upper limbs showed evidence of vasculitis affecting digital arterioles on both sided and right subclavian occlusion. The patient received pulse methylprednisolone followed by cyclophosphamide pulse therapy, the latter continuing on a monthly basis for 6 months with appreciable improvement and remission of the vasculitic process; follow‐up MRA showed reperfusion of the previously occluded subcalvian artery. To the authors’ knowledge vasculitis complicating the course of ulcerative colitis is a rare association and is only sporadically reported in the literature. This rare entity should be diagnosed early and aggressively treated; MRA is a very promising diagnostic tool that is suitable for both diagnosis and follow‐up of patients with this rare entity. 相似文献
5.
6.
Adenosine and active hyperemia in dog skeletal muscle 总被引:5,自引:0,他引:5
7.
Y chromosome microdeletions, in azoospermic or near-azoospermic subjects, are located in the AZFc (DAZ) subregion 总被引:9,自引:2,他引:9
Submicroscopic deletions of the Y chromosome and polymorphisms of the
androgen receptor (AR) gene in the X chromosome have been observed in men
with defective spermatogenesis. To further define the subregions/genes in
the Y chromosome causing male infertility and its relationship to
polymorphisms of the AR polyglutamine tract, we screened the genomic DNA of
202 subfertile males and 101 healthy fertile controls of predominantly
Chinese ethnic origin. Y microdeletions were examined with 16
sequence-tagged site (STS) probes, including the RBM and DAZ genes,
spanning the AZFb and AZFc subregions of Yq11, and related to the size of
trinucleotide repeat encoding the AR polyglutamine tract. Y microdeletions
were detected and confirmed in three out of 44 (6.8%) of azoospermic and
three out of 86 (3.5%) severely oligozoospermic patients. No deletions were
detected in any of the patients with sperm counts of >0.5 x 10(6)/ml,
nor in any of the 101 fertile controls. All six affected patients had
almost contiguous Y microdeletions spanning the entire AZFc region
including the DAZ gene. The AZFb region, containing the RBM1 gene, was
intact in five of the six subjects. Y deletions were not found in those
with long AR polyglutamine tracts. Our study, the first in a Chinese
population, suggest a cause and effect relationship between Y
microdeletions in the AZFc region (possibly DAZ), and azoospermia or
near-azoospermia. Y microdeletions and long AR polyglutamine tracts appear
to be independent contributors to male infertility.
相似文献
8.
B. AASTED D. BERNSTEIN D. G. KLAPPER A. EL KHOLY R. M. KRAUSE 《Scandinavian journal of immunology》1979,9(1):61-67
The human lymphokine, leucocyte migration-inhibitory factor (LIF), appears to be a serine esterase and protease by virtue of its susceptibility to the irreversible enzyme inhibitor, phenylmethylsulfonyl fluoride (PMSF), and by the ability of arginine esters and amides to protect LIF against PMSF-induced inactivation. In this paper, three methods are described by which putative substrates for LIF may be investigated. Thus, molecules satisfying the substrate specificities of this lymphokine should (1) protect LIF against inactivation by PMSF, (2) reduce LIF activity in vitro on polymorphonuclear leucocytes, and (3) reduce the esterolytic activity of purified LIF-rich supernatants. The first two reactions were tested by means of the leucocyte migration agarose technique; the third reaction was tested by a sensitive enzyme assay using tritiated tosyl arginine methyl ester as substrate. Guanosine 3',5'-cyclic monophosphoric acid, which is capable of protecting LIF against PMSF-induced inhibition, also inhibited the esterolytic activity of the purified LIF preparation. Four synthetic oligopeptide substrates for trypsin, thombin and plasmin were investigated. Only one, the thrombin- and trypsin-specific benzoyl-phenylalanyl-valyl-agarine-p-nitroanilide, possessed high affinity for the LIF molecule and may therefore prove to be a potent substrate for this lymphokine. 相似文献
9.
Flatow EL Miller SR Neer CS 《Journal of shoulder and elbow surgery / American Shoulder and Elbow Surgeons ... [et al.]》1993,2(1):2-10
The treatment of 17 chronic, unreduced anterior dislocations of the shoulder was reviewed. Eleven women and six men with on average age of 67 years (range 36 to 88 years) were studied. The duration of dislocation averaged 2.3 years (8 weeks to 8 years). Seven patients were treated without surgery despite severe functional deficits, for reasons of health or motivation. Ten were treated with surgery. One patient with preserved joint surfaces underwent open reduction and corticoid transfer to bone graft an eroded anterior glenoid. Nine patients with destroyed articular surfaces underwent unconstrained replacement orthroplosty. Humeral retroversion was increased for stability. The soft tissues were reattached, and rehabilitation was modified as with a repair of recurrent dislocations. Anterior glenoid erosion was often present and required bone grafting to support the glenoid component in four shoulders. Two chronic rotator cuff tears required repair. Nine patients were followed from 2 to 6 years, with an average of 3.9 years. The results were four excellent, four satisfactory, and one unsatisfactory. Although the reconstruction is complex, the surgical results were clearly superior to those of the nonoperative group. 相似文献
10.
Injury to the long thoracic nerve causing paralysis or weakness of the serratus anterior muscle can be disabling. Patients with serratus palsy may present with pain, weakness, limitation of shoulder elevation, and scapular winging with medial translation of the scapula, rotation of the inferior angle toward the midline, and prominence of the vertebral border. Long thoracic nerve dysfunction may result from trauma or may occur without injury. Fortunately, most patients experience a return of serratus anterior function with conservative treatment, but recovery may take as many as 2 years. Bracing often is tolerated poorly. Patients with severe symptoms in whom 12 months of conservative treatment has failed may benefit from surgical reconstruction. Although many surgical procedures have been described, the current preferred treatment is transfer of the sternal head of the pectoralis major tendon to the inferior angle of the scapula reinforced with fascia or tendon autograft. Many series have shown good to excellent results, with consistent improvement in function, elimination of winging, and reduction of pain. 相似文献