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21.
Young men presenting to a General Surgical Unit with acute epididymitis underwent microbiological investigation, including culture for Chlamydia trachomatis. The results were compared with similar investigations in an asymptomatic control population and with patients presenting to the Department of Genito-urinary Medicine with urethral discharge. Chlamydia trachomatis was cultured from 15% of patients with acute epididymitis and a further 15% had serological evidence of exposure to Chlamydia. Nearly 50% of patients attending the Genito-urinary clinic grew Chlamydia from the urethra. The background prevalence of Chlamydia in the control population was low. It is necessary to identify the significant minority of young men with acute epididymitis associated with chlamydial infection, because of the risk of pelvic inflammation and infertility in their female partners. At present this can only be achieved by submitting all young men with acute epididymitis to full microbiological investigation.  相似文献   
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Given the significant morbidity associated with current post-transplant immunosuppressive regimens, induction of immune tolerance continues to be an important goal of clinical organ transplantation. While many strategies for inducing tolerance have been successfully applied in murine models, significant barriers are faced when translating these approaches to the clinic. This has necessitated pre-clinical studies in the more closely related model system, the non-human primates (NHP). In this review, we will discuss the four most prominent strategies for inducing transplantation tolerance and highlight their relative success and shortcomings in NHP. These strategies are: (1) T-cell costimulation blockade (2) mixed chimerism induction (3) T-cell depletion and (4) tolerance induction through regulatory T-cells. After discussing the progress that has been made with each of these strategies, we will identify this field's most pressing unmet needs and discuss how we may best overcome the resulting barriers to tolerance induction.  相似文献   
24.
A 29-year-old white woman had short limbs, hyperextendable joints, fine skin and body hair, anergy to common skin test antigens, subnormal lymphocyte response to phytohemagglutinin, and increased numbers of natural killer cells, characteristic of cartilage-hair hypoplasia, an autosomal, recessively inherited disorder found in America mainly among the old-order Amish. Her forearm skin was hyperextendable and numerous verrucae were present on the digits of her hands. A skin biopsy from hyperextendable skin showed ovoid, 10- to 20-micron bodies in the papillary dermis. Ultrastructurally, the bodies were interpreted as abnormal elastic fibers.  相似文献   
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26.
Carotid body tumors: a subject review and suggested surgical approach   总被引:1,自引:0,他引:1  
Carotid body tumors are a rare but potentially difficult surgical entity. Their pathology, physiology, and natural history are reviewed along with surgical results reported in the literature. A surgical approach for removal of these tumors is presented which differs significantly from the recommended techniques in that emphasis is placed on intraoperative monitoring of cerebral blood flow, the the selective use of shunts, a tumor-adventitial plane of dissection, preservation of the carotid artery complex, and mobilization of the parotid gland. Thirteen cases using these techniques are reviewed. The mortality rate and the incidence of cerebrovascular sequelae were both 0%. The major morbidity consisted of injury to the lower cranial nerves in five patients (39%) with tumors larger than 5 cm in length.  相似文献   
27.
Subconjunctival sustained release 5-fluorouracil.   总被引:1,自引:0,他引:1  
The authors have developed a sustained release device for 5-fluorouracil (5-FU) made up of a 12 mg pellet of drug coated in a mixture of permeable and impermeable polymers. When implanted subconjunctivally in rabbits, these devices released 5-FU at approximately 1 mg/d for over 10 days. Devices were implanted into four cynomolgus monkey eyes after posterior lip sclerotomy. One eye (treatment) received a device that contained 12 mg 5-FU and the other eye (control) received a placebo device that contained no drug. In control eyes, intraocular pressures returned to normal within 1 wk. In treatment eyes, pressures remained significantly lower throughout the experimental period (3 mo). There was no indication of impaired wound healing, corneal toxicity, inflammation, or damage to the ciliary body in rabbits or monkeys.  相似文献   
28.
Mediastinal tumors.   总被引:1,自引:0,他引:1  
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29.
Although psychiatric hospitals are thought to be the main focus of care for the mentally ill, China has not inherited the large asylums that were, and are, such a feature in the West. China has developed her own model of community care for the mentally ill, which is coherent with what are seen to be the available resources and fits into existing structures of social organisation. The elements in this model include small neighbourhood workstations, factory clinic liaison work, 'home beds' and neighbourhood care units. So far alternative accommodation schemes appear to have no part to play in the model. The reasons for this are discussed. However, while the Chinese model of community care for the mentally ill is quite well articulated, there appear to be major problems in ensuring its implementation.  相似文献   
30.
We have used a sensitive and specific in vivo killing assay to monitor the kinetics, anatomic location and mechanisms controlling NK-mediated rejection of Balb/c bone marrow by C57BL/6 natural killer (NK) cells. We find that NK killing of fully allogeneic bone marrow is a rapid, highly efficient process, leading to substantial rejection of transplanted marrow within 6 h of transplant and elimination of 85% of the transplanted cells within 2 days. NK-mediated rejection occurred predominantly in the spleen, with sparing of rejection in the bone marrow and lymph nodes. Rejection was dependent on Perforin gene function, but was independent of interferon-gamma. Finally, rejection of Balb/c bone marrow by B6 NK cells required signaling through the Ly49D receptor, but occurred despite blockade of NKG2D, which distinguishes these results from previous studies using semiallogeneic transplant pairs. These results identify NK cells as highly active mediators of bone marrow rejection, and suggest that inhibiting NK function early during transplantation may increase the efficiency of engraftment and allow successful engraftment of limiting doses of donor bone marrow.  相似文献   
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