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1.
The initial management of bladder outflow obstruction typically related to benign prostatic hyperplasia (BPH) falls to a large extent within the remit of general practice. Referral onwards to secondary care typically arises following the failure to respond to conservative measures or when complications have supervened; the most significant of which is urinary retention. In the hospital setting, anaesthesia, constipation and immobility are the common precipitants. What follows is a practical guide to the management of these situations and provides an overview of the conservative, medical, minimally invasive and surgical treatments available. 相似文献
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A Rock 《Canadian Medical Association journal》1997,157(12):1730-1731
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Early life precursors of psychiatric outcomes in adulthood in subjects at risk for schizophrenia or affective disorders. 总被引:2,自引:0,他引:2
L Erlenmeyer-Kimling D Rock E Squires-Wheeler S Roberts J Yang 《Psychiatry research》1991,39(3):239-256
In the New York High-Risk Project (NYHRP), 186 offspring of schizophrenic, affectively ill, and psychiatrically normal parents have been followed prospectively from 1971-72 to the average age of 27 years in 1990 with the goal of identifying early precursors of later psychopathology. In this report, we use path analyses to examine the relationship of several life-history variables to three pathological outcomes in the offspring: namely, psychosis, psychiatric hospitalization, and psychological dysfunction. The chief direct relationship with these outcomes is the effect of having a schizophrenic parent. The latter effect is also mediated indirectly by IQ. 相似文献
7.
The cytotoxic reactivity of 18 predefined class I HLA serum antibodies was compared with that of antibody preparations containing anticoagulants. ACD-A, EDTA, 4% citrate and heparin plasmas all showed lower cytotoxicity than serum antibodies. Recalcification of both platelet-rich and platelet-poor ACD-A plasma did not fully restore the antibody reactivity, suggesting a detrimental effect of calcium chelation. This effect was exclusive of volume or of any platelet or plasma protein involvement. The changes in pH contributed to the lower reactivity and to the increased lympholytic effect, whereas adjusting the pH toward the serum value improved the reactivity. Heat-inactivated antibodies showed only a slightly reduced cytotoxicity. Heparin had the least effect of all anticoagulants on the reactivity, although in heparin there was a definite dose-dependent decline in cytotoxic titer which was probably related to anticomplementary activity. Calcium chelators, such as EDTA and citrate, showed marked cytotoxic inhibition at half the usual complement concentration. This effect was more pronounced when the anticoagulant and lymphocytes were incubated prior to cytotoxicity testing. At the complement concentrations used, the inhibitory effects of the citrate anticoagulants appeared to be primarily calcium-related. Inhibition tests, serial titrations and testing of varying calcium concentrations confirmed the superiority of serum as antibody source. 相似文献
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E H Rock 《Ear, nose, & throat journal》1991,70(4):245-250
Impedance audiometry offers a clinically practical method for measuring the physical volume in cc of air space medial to the hermetically sealed probe tip. Knowledge of the air space volume is meaningful when average norms are known, either when the TM is intact or, more significantly, when the TM is perforated. With the latter, the temporally dynamic space changes during external, middle ear and/or mastoid disease, the size of the total air space measured offers objective information when determined over time. The resultant volume can offer an indirect mirror readout of progression or regression of a disease process. Likewise, historically there may be a close relationship between eustachian tube function and the overall air cell space within the petrotympanomastoid bone. In such conditions, the smaller the air cell space, the poorer the eustachian tube function. The PVT offers a more expedient clinical tool over roentgenography for measuring the viable air space of the middle ear and petromastoid air cell system. Since the PVT is used primarily with an open system (i.e. with a perforated TM) electroacoustic volumetric determinations with a 220 Hz acoustic input more reliably represents the actual volume present. 相似文献
9.
David R. Young Lih-Yuann Shin Michael G. Rock Frank J. Frassica Petri Virolainen Edmund Y. S. Chao 《Journal of orthopaedic research》1997,15(5):773-780
The reconstruction of large bone and joint defects after the resection of malignant tumors remains a major challenge. Chemotherapy has significantly lowered the risk of metastasic disease, but complications associated with reconstructive techniques continue to result in late morbidity. In the present study, biomechanical torsion testing, gait analysis, and histomorphometric and scanning electron microscopic evaluations of 24 dogs were used to examine the effects of preoperative and postoperative administration of cisplatin on the biologic fixation of a porous-coated segmental replacement prosthesis. The chemotherapy consisted of four cycles of cisplatin administered at a dosage of 75 mg/m:2 preoperatively or postoperatively. The healing was enhanced by use of an autogenous corticocancellous bone graft. The graft was placed evenly around the prosthesis and the adjacent femoral cortex. Mechanical analyses of torsional stiffness, yield strength, and maximum strength revealed no statistically significant differences between the groups at 12 weeks. Such lack of difference was mainly due to the penetration of highly organized fibrous tissue into the porous surface; this provided strong fixation of the implant to bone even in the absence of bone ingrowth. Although bone ingrowth into the prostheses was not affected, electron microscopic, histomorphometric, and radiologic analyses showed a clear difference in the formation of new bone around the prosthesis. Preoperative chemotherapy did not alter the formation of new bone, but specimens from animals treated postoperatively with cisplatin showed significantly less bone graft resorption and less new bone formation. Hence, the effect of cisplatin administration caused only a temporary delay, not a permanent effect, on extracortical capsule formation. The formation of extracortical bone and soft tissue might prevent debris-incised osteolysis and, therefore, prevent late complications by forming a tight capsule around the bone-prosthetic interface. 相似文献
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M G Rock 《Canadian journal of surgery》1988,31(6):385-389
Soft-tissue sarcomas account for only 1% of all malignant lesions. The Canadian Sarcoma Group encourages the investigation and management of these tumours at tertiary institutions, where a multidisciplinary team can handle the complex problems. Staging of these tumours implies accurate anatomic determination of the extent of disease, the histogenesis and grade of the tumours and the presence of regional or distant metastases. Arteriography, computed tomography and magnetic resonance imaging can accurately define the tumour before biopsy. The biopsy should be muscle-splitting to minimize contamination of additional compartments and should allow inclusion of the biopsy site at definitive surgical resection. It should be done at the institution where definitive management will be performed. Regional lymph-node involvement can be detected using magnetic resonance imaging or gallium scanning, whereas for distant metastases, specifically of lung, computed tomography is the method of choice. To date no one staging system for soft-tissue sarcomas has been universally accepted. A hybrid, encompassing the advantages of each system, is being formulated. 相似文献