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991.
992.

Background  

Long head biceps (LHB) degeneration, in combination with rotator cuff tears, can be a source of chronic shoulder pain. LHB tenotomy reduces pain and improves joint function although the pathophysiological context is not well understood. Tendon integrity depends on the extracellular matrix (ECM), which is regulated by matrix metalloproteinases (MMP). It is unclear which of these enzymes contribute to LHB but we chose to study MMP 1, 3, and 9 and hypothesized that one or more of them may be altered in LHB, whether diagnosed preoperatively or intraoperatively. We compared expression of these MMPs in both LHB and healthy tendon samples.  相似文献   
993.
CD22 is a B cell-restricted glycoprotein involved in cell adhesion and signaling. Since CD22 is likely to play an important role in interactions between B cells and other cells, and in regulating signaling thresholds, we characterized the expression of murine CD22 during different stages of B cell development. In contrast to previous reports, we show that CD22 is expressed on B cell progenitors prior to expression of IgM. IL-7-responsive B cell precursors from the fetal liver and early B lineage cells (B220+IgM-) from the bone marrow both express a low density of surface CD22. The majority of the earliest B cell progenitors (B220+IgM-CD43+) in the bone marrow, however, do not express CD22. As B cells mature, the density of CD22 molecules on the cell surface increases. B220brightIgM+ bone marrow cells express high levels of CD22, as do splenic B cells. The correlation of CD22 levels with B cell maturation is replicated in an in vitro culture system, which distinguishes stages of B cell development based on function. Following activation of mature resting splenic B cells with anti-mu mAb or lipopolysaccharide (LPS), levels of CD22 decrease. Finally, we show that the addition of anti-CD22 mAb augments the proliferative response of both anti-mu- and LPS-stimulated B cells, suggesting a role for CD22 in diverse signaling pathways.   相似文献   
994.
995.
The cavernous sinus dural arteriovenous fistulas of three patients were successfully embolised by using Onyx (Onyx Liquid Embolic System, MTI, Irvine, CA, USA) as the sole embolic agent, through direct percutaneous transorbital punctures of the cavernous sinuses. Our early experience suggests that this direct approach, coupled with the unique physical properties of Onyx, is a safe and effective alternative to treat cavernous sinus dural arteriovenous fistulas when the conventional transvenous routes are inaccessible.  相似文献   
996.
The number of thoracic surgery cases performed on the robotic platform has increased steadily over the last two decades. An increasing number of surgeons are training on the robotic system, which like any new technique or technology, has a progressive learning curve. Central to establishing a successful robotic program is the development of a dedicated thoracic robotic team that involves anesthesiologists, nurses, and bed-side assistants. With an additional surgeon console, the robot is an excellent platform for teaching. Compared to current methods of video-assisted thoracoscopic surgery (VATS), the robot offers improved wristed motion, a magnified, high definition three-dimensional vision, and greater surgeon control of the operation. These advantages are paired with integrated adjunctive technology such as infrared imaging. For pulmonary resection, these advantages of the robotic platform have translated into several clinical benefits, such as fewer overall complications, reduced pain, shorter length of stay, better postoperative pulmonary function, lower operative blood loss, and a lower 30-day mortality rate compared to open thoracotomy. With increased experience, cases of greater complexity are being performed. This review article details the process of becoming an experienced robotic thoracic surgeon and discusses a series of challenging cases in robotic thoracic surgery that a surgeon may encounter “beyond the learning curve”. Nearly all thoracic surgery can now be approached robotically, including sleeve lobectomy, pneumonectomy, resection of large pulmonary and mediastinal masses, decortication, thoracic duct ligation, rib resection, and pulmonary resection after prior chest surgery and/or chemoradiation.  相似文献   
997.
Two frequent missense mutations in Pendred syndrome   总被引:8,自引:3,他引:8  
Pendred syndrome is an autosomal recessive disorder characterized by early childhood deafness and goiter. A century after its recognition as a syndrome by Vaughan Pendred, the disease gene ( PDS ) was mapped to chromosome 7q22-q31.1 and, recently, found to encode a putative sulfate transporter. We performed mutation analysis of the PDS gene in patients from 14 Pendred families originating from seven countries and identified all mutations. The mutations include three single base deletions, one splice site mutation and 10 missense mutations. One missense mutation (L236P) was found in a homozygous state in two consanguineous families and in a heterozygous state in five additional non-consanguineous families. Another missense mutation (T416P) was found in a homozygous state in one family and in a heterozygous state in four families. Pendred patients in three non-consanguineous families were shown to be compound heterozygotes for L236P and T416P. In total, one or both of these mutations were found in nine of the 14 families analyzed. The identification of two frequent PDS mutations will facilitate the molecular diagnosis of Pendred syndrome.   相似文献   
998.
Four distinct studies were carried out using two data sets ofpercutaneous epididymal sperm aspiration (PESA) and intracytoplasmicsperm injection (ICSI) procedures performed from March 1993to January 1997. In study A, an analysis of 181 ICSI treatmentcycles following PESA revealed a successful epididymal spermretrieval rate of 83%. It confirmed that PESA is an effectivesperm retrieval method and the associated ICSI pregnancy rate(35% per embryo transfer) compared favourably with that of othersperm retrieval methods. In study B, the relevance of a priordiagnostic PESA procedure was ascertained by comparing the spermretrieval rates in two groups of patients having their firstICSI treatment cycle with spermatozoa retrieved through PESA.Group B1 (n=50) had diagnostic PESA prior to the ICSI treatmentcycle PESA procedure, unlike patients in group B2 (n=64) whodid not. The sperm retrieval rate in the treatment cycle procedurewas not different at 90 and 82.8% for groups B1 and B2 respectively.However, the discontinuation of diagnostic PESA is fraught withproblems including liability to medico-legal sanctions. In studyC, analysis of 177 treatment cycles involving PESA and ICSIrevealed a successful sperm retrieval rate by PESA of 82% inthe first cycle, 93% in the second, 96% in the third and 100%in the fourth cycle. The same trend was evident when sperm retrievalwas examined in relation to each of the epididymides. Retrievedspermatozoa were found to be motile in 67-100% of cases andthe frequency of samples containing motile spermatozoa did notdecrease with increase in the number of PESA attempts. Theseresults show that PESA does not jeopardize future epididymalsperm retrieval. In study D, the outcome of treatment with ICSIusing ejaculated spermatozoa (305 cycles) (group D1) was comparedwith that of ICSI using spermatozoa obtained through PESA (54cycles) (group D2). The median age of women in the two groupsof couples was similar (34 years). In group D1, 70% of metaphaseII oocytes were fertilized compared with 61% in group D2 (P<0.01).The cleavage rate and the median numbers of transferred andcryopreserved embryos were similar in both groups. There wasno significant difference between the clinical pregnancy rates(33 and 42% in groups D1 and D2 respectively). Our results showthat the outcome of PESA-ICSI treatment compared favourablywith that of ICSI using ejaculated spermatozoa.  相似文献   
999.
1000.
杨悦武  吴如金 《药学学报》1992,27(10):758-762
对睾酮及表睾酮的三甲基硅烷化进行了详细考察,找到了较好的抗氧剂巯基乙醇,确定了较好的衍生化条件,衍生化产物单一。并采用GC—MS法测定了尿中睾酮与表睾酮的比值。实验条件为:以氦为载气,SE—54熔融石英柔性毛细管柱、程序升温进行样品分离,多离子检测(MID),监测m/z432的离子。该法专属、灵敏、快速。睾酮与表睾酮比值在1:1~10:1(睾酮为20ng/μl)与相应峰面积比呈线性关系(r=0.998),最低检测限为1ng,最低检测尿药浓度为8ng/ml。  相似文献   
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