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911.
The bandicoot is unique among marsupials in possessing a corpus luteum of pregnancy which continues to secrete progesterone during lactation. Different factors which may influence the activity of this corpus luteum were examined. There was no correlation between the number of pouch young and the plasma progesterone concentration. Similarly, bromocriptine did not appear to cause a dramatic decrease in plasma progesterone early in lactation, however, it may induce premature regression of the corpus luteum late in lactation. Corpora lutea were not observed in the ovaries of two out of six bandicoots treated with bromocriptine late in lactation. Although the corpus luteum may influence ovarian activity early in lactation, and corpus luteum does not appear to influence reproduction late in lactation. Removal of corpora lutea at Day 30 of lactation caused an abrupt decline in plasma progesterone; however, the birth of the subsequent litter occurred on Days 58 and 61 (N = 2), births normally occurring on Day 60.  相似文献   
912.
913.
Recently, we examined 2 cases of hypertrophic cardiomyopathy (HCM) presenting with sustained ventricular tachycardia (VT). One case was a 62 year old male with midventricular hypertrophy and monomorphic sustained VT. After admission, the efficacies of procainamide, disopyramide, aprindin, flecainide, mexiletine and verapamil were evaluated by means of continuous electrocardiographic monitoring. Verapamil prevented the recurrence of sustained VT and markedly reduced the frequency and number of runs of nonsustained VT. In the electrophysiologic study, rapid VT was induced by double extrastimuli at the right ventricular apex. Intravenous verapamil at a dose of 10 mg prevented the induction of VT. The patient was discharged on verapamil and remains asymptomatic after 3 months of follow up. The other case was a 34 year old female who was a survivor of cardiac arrest. Monomorphic VT was observed on emergency admission and was converted to sinus rhythm by direct current cardioversion after resuscitation. In the electrophysiologic study, rapid VT was induced by double extrastimuli at the right ventricular outflow tract. Verapamil at a dose of 10 mg prevented the induction of VT. These 2 cases of HCM are rare in that they presented with sustained VT. It is also of interest that verapamil, which has been used conventionally in HCM, prevented VT.  相似文献   
914.
In the search for HLA-linked immune response genes that control susceptibility to tuberculosis, we performed HLA typing and measured antibody titers to well-defined Mycobacterium tuberculosis antigenic determinants in 101 patients with sputum smear-positive pulmonary tuberculosis and 64 healthy controls from Surabaya, Indonesia. HLA-DR2 and DQw1 were associated with sputum smear-positive pulmonary tuberculosis (attributable risk = 36% and 39%, respectively), while DQw3 was associated even more strongly with the control group (preventive fraction = 57%). Antibody titers to the TB71 and TB72 epitopes of the 38-kDa protein, present only on tubercle bacilli, were strongly associated with DR2 (Pcorr = .001 and .024, respectively). The association of both the disease and the antibody response to the 38-kDa antigen of M. tuberculosis with Class II HLA genes HLA-DR2 indicates that Ir-gene-mediated regulation of the immune response to this antigen may be of pathogenic significance for the development of sputum smear-positive tuberculosis.  相似文献   
915.
A genomic library of Mycobacterium tuberculosis strain Aoyama B in Escherichia coli K-12 was constructed by cloning Sau 3A I cleaved M. tuberculosis Aoyama B chromosomal DNA into pUC18, pUC181 or pUC182. Clones reacting with anti-PPDs-rabbit-serum were screened by immunoblotting among 3 x 10(4) clones. Seven clones were selected; designating pAT 01, pAT 101, pAT 102, pAT 103, pAT 104, pAT 105 and pAT 201. On Western blotting, they were shown to produce 15 kD (pAT 01, pAT 101, pAT 105), 18 kD (pAT 103) and 60 kD (pAT 102, pAT 201) peptide antigens. Restriction endonuclease map of each of the above clones was composed, and putative coding frames of anti-PPDs-rabbit-serum reactive peptides were deduced by analysing deletion derivatives. Nucleotide sequence of pAT 01, encoding for 15 kD peptide antigen was analyzed, and a Hinf I-Hinf I fragment in pAT 01 was subcloned into pUC 18 lambda CPL 1 to determine the direction of its reading frame. The origin of promoter that drives cloned mycobacterial genes in E. coli was discussed.  相似文献   
916.
917.
918.
Lesions typical of subacute cutaneous lupus erythematosus developed in an elderly woman after 6 months of PUVA (8-methoxypsoralen and longwave ultraviolet light) therapy for psoriasis. Pancytopenia, antibodies to double-stranded DNA, and hypocomplementemia developed concurrently with the appearance of the cutaneous lesions. With discontinuation of photochemotherapy, the cutaneous lesions disappeared and the pancytopenia improved.  相似文献   
919.
Retrosternal dislocations of the clavicle have been reported previously in adults throughout the orthopedic literature. However, in children few cases have been noted in either the pediatric, emergency, or orthopedic literature. The potential for great vessel injury as well as acute airway compromise makes the retrosternal disruption of the sternoclavicular joint a surgical emergency that must be diagnosed quickly. Diagnosis is enhanced by the cephalic tilt view and by computed tomography (CT scan), as planar x-ray and tomography do not always reveal this potentially life-threatening condition. Surgical consultation must be sought acutely; however, management may need to begin prior to definitive repair. Emergency management begins by suspecting the injury, and with immediate airway and circulatory support for the patient.  相似文献   
920.
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