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71.
Responses to the synthetic terpolymer L-glutamic acid, L-lysine, L-tyrosine (GLT) in the mouse are controlled by H-2-1inked Ir-GLTgenes. (Responder × nonresponder) F(1) hybrid mice, themselves phenotypic responders, can be primed with GLT to develop specific helper cells capable of interacting with 2,4-dinitrophenyl hapten (DNP)-primed F(1) B cells in response to DNP-GLT. Unlike the indiscriminant ability of F(1) helper T cells for conventional antigens (i.e. not Ir gene-controlled), which can help B cells of either parental type (as well as F(1)) equally well, GLT-primed F(1) T cells can only provide help under normal circumstances for B lymphocytes of responder parent origin; they are unable to communicate effectively with nonresponder parental B cells (1, and the present studies). The present studies reveal, however, that the induction of a parental cell-induced allogeneic effect during priming of F(1) mice to GLT actually dictates the direction of cooperating preference that will be displayed by such F(1) helper cells for B cells of one parental type or the other. Thus, F(1) T cells, primed to GLT under the influence of an allogeneic effect induced by parental BALB/c cells, develop into effective helpers for nonresponder A/J B cells, but fail to develop effective helpers for responder BALB/c B cells, and vice-versa. In contrast, F(1) T cells, primed to GLT under the influence of an allogeneic effect induced by either parental type, display significantly enhanced levels of helper activity for B cells derived from F(1) donors. These results are interpreted to reflect the existence of two interdependent events provoked by the allogeneic effect: one event augments the differentiation of GLT-specific helper T cells belonging to the subset corresponding to the opposite parental type; this would explain the development of increased helper activity provided to partner B cells of opposite parental type (as well as of F(1) origin). The second event, we postulate, involves the production of responses against the receptors which normally self-recognize native cell interaction determinants; this form of anti-idiotype response is restricted against self- recognizing receptors of the same parental type used for induction of the allogeneic effect, hence explaining diminished helper activity of such F(1) cells for partner B lymphocytes of corresponding parental type.  相似文献   
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背景和目的:国际5国脑血管病专家提出一种新的腩卒中亚型分类法,旨在介绍完整的"脑卒中表型"分类的新观念,该分类是包括脑卒中的病因和存在的所有病因相关的疾病,并将病因疾病按严重程度分成3级.  相似文献   
74.

Background

Appendiceal mucocele is an infrequent well-recognized entity that can present in a variety of clinical syndromes or can be asymptomatic and discovered incidentally.

Patients and Methods

Nineteen patients with a diagnosis of primary appendiceal mucocele treated in our institution between January 1, 1987 and December 31, 2006 were included in this retrospective analysis.

Results

The histological examination of the specimens revealed simple and hyperplastic appendiceal mucocele in nine cases (47%), mucinous appendiceal cystadenoma in eight cases (42%), and mucinous appendiceal cystadenocarcinoma in two cases (11%). Thirteen patients (68%) underwent appendectomy, five patients (26%) right colectomy, and two patients (6%) underwent right colectomy for invasive appendiceal cystadenocarcinoma and at the same time right nephrectomy and sigmoidectomy, respectively, for concomitant malignancy.

Conclusion

Mucocele of the appendix may be related to a benign or malignant appendiceal process, leading to individualized diagnosis and treatment.  相似文献   
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Blepharoplasty is one of the most commonly performed operations in plastic surgery, especially among middle-aged patients. Ablative lasers, especially the carbon dioxide laser, assist in tissue cutting and hemostasis. These lasers also offer skin resurfacing with its unique advantages despite the prolonged downtime. The authors present their laser-assisted blepharoplasty experience and the recent addition of one simply performed, inferior lateral retinaculum plication to the procedure (single suture traction technique, SSTT). Hence, the need for laser skin resurfacing of the lower eyelid has been reduced due to the skin traction applied, avoiding the long period required for resolution of erythema and potential hyperpigmentation. Furthermore, the tightening effect on the canthal ligament offers a more youthful look to the surgically treated eye. Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users.  相似文献   
78.

Background

With ageing, comorbidities such as neurocognitive impairment increase among people living with HIV (PLWH). However, addressing its multifactorial nature is time-consuming and logistically demanding. We developed a neuro-HIV clinic able to assess these complaints in 8 h using a multidisciplinary approach.

Methods

People living with HIV with neurocognitive complaints were referred from outpatient clinics to Lausanne University Hospital. Over 8 h participants underwent formal infectious disease, neurological, neuropsychological and psychiatric evaluations, with opt-out magnetic resonance imaging (MRI) and lumbar puncture. A multidisciplinary panel discussion was performed afterwards, with a final report weighing all findings being produced.

Results

Between 2011 and 2019, a total of 185 PLWH (median age 54 years) were evaluated. Of these, 37 (27%) had HIV-associated neurocognitive impairment, but they were mainly asymptomatic (24/37, 64.9%). Most participants had non-HIV-associated neurocognitive impairment (NHNCI), and depression was prevalent across all participants (102/185, 79.5%). Executive function was the principal neurocognitive domain affected among both groups (75.5% and 83.8% of participants impaired, respectively). Polyneuropathy was found in 29 (15.7%) participants. Abnormalities in MRI were found in 45/167 participants (26.9%), being more common among NHNCI (35, 77.8%), and HIV-1 RNA viral escape was detected in 16/142 participants (11.2%). Plasma HIV-RNA was detectable in 18.4% out of 185 participants.

Conclusions

Cognitive complaints remain an important problem among PLWH. Individual assessment from a general practitioner or HIV specialist is not enough. Our observations show the many layers of HIV management and suggest that a multidisciplinary approach could be helpful in determining non-HIV causes of NCI. A 1-day evaluation system is beneficial for both participants and referring physicians.  相似文献   
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80.

Background  

Interferon gamma (IFNγ) is a pro-inflammatory cytokine, which may be up-regulated after trauma to the peripheral or central nervous system. Such changes include reactive gliosis and synaptic plasticity that are considered important responses to the proper regenerative response after injury. Also, IFNγ is involved in the upregulation of the major histocompatibility complex class I (MHC class I), which has recently been shown to play an important role in the synaptic plasticity process following axotomy. There is also evidence that IFNγ may interfere in the differentiation and survival of neuronal cells. However, little is known about the effects of IFNγ absence on spinal cord neurons after injury.  相似文献   
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