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We report two cases of capsular bag contraction that occurred within 1 month after continuous curvilinear capsulorhexis, phacoemulsification, and intraocular lens implantation. Neither patient had a known risk for this complication. Both patients had a neodymium:YAG laser anterior capsulotomy, which disrupted the capsulorhexis margin and led to prompt capsular bag distension.  相似文献   
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CVI is a common disease with significant morbidity that results from venous hypertension of the extremities. Increased perfusion pressure probably traps excessive numbers of white blood cells in the capillaries. Activated leukocytes subsequently damage capillary endothelium, increase capillary permeability, and cause ischemia of the overlying skin as a result of leakage of fibrinogen and formation of a fibrin cuff. Diagnosis of CVI is not difficult because its clinical manifestations are usually evident. Vascular compression therapy remains the foundation of medical management for CVI. Refractory cases may require a combined medical and operative approach.  相似文献   
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The threshold for generation of lung hemorrhage in adult mice by pulsed ultrasound has been shown to be approximately 1 MPa at the surface of the lung (10-microseconds pulse and a carrier frequency of 2 MHz). This investigation used neonatal swine to determine if the findings for mice can be generalized to other species. After exploratory observations, the inverse sampling method was used in a primary study (22 animals, 88 exposure sites) to determine the threshold for lung hemorrhage in neonatal swine. The primary study was followed by a separate confirmation study (13 animals, 48 exposure sites), testing the conclusions of the first study and comparing damage at subthreshold levels with sham-exposed animals. A separate investigation explored the histological nature of tissue damage at suprathreshold levels. A 2.3-MHz focused transducer (10 microseconds at 100-Hz pulse-repetition frequency) was incremented vertically for a distance of 2 cm over the chest of the subject for a total exposure period of 16 min. Animals were euthanized and lungs were scored by visual inspection for numbers and areas of gross hemorrhages. The threshold level for hemorrhage was approximately 1.5 MPa peak positive pressure in water at the surface of the animal or, at the surface of the lung, 1.1 MPa peak positive pressure, 1 MPa fundamental pressure, 0.9 MPa maximum negative pressure, 25 W cm-2 pulse average intensity or a mechanical index of 0.6. These values are essentially the same as those reported for adult mice.  相似文献   
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Recombinant adeno-associated virus 2 (AAV) virions were constructed containing a gene for resistance to neomycin (neoR), under the control of either the herpesvirus thymidine kinase (TK) gene promoter (vTK-Neo), or the human parvovirus B19 p6 promoter (vB19-Neo), as well as those containing an upstream erythroid cell-specific enhancer (HS-2) from the locus control region of the human beta-globin gene cluster (vHS2-TK-Neo; vHS2-B19-Neo). These recombinant virions were used to infect either low density or highly enriched populations of CD34+ cells isolated from human umbilical cord blood. In clonogenic assays initiated with cells infected with the different recombinant AAV-Neo virions, equivalent high frequency transduction of the neoR gene into slow-cycling multipotential, erythroid, and granulocyte/macrophage (GM) progenitor cells, including those with high proliferative potential, was obtained without prestimulation with growth factors, indicating that these immature and mature hematopoietic progenitor cells were susceptible to infection by the recombinant AAV virions. Successful transduction did not require and was not enhanced by prestimulation of these cell populations with cytokines. The functional activity of the transduced neo gene was evident by the development of resistance to the drug G418, a neomycin analogue. Individual high and low proliferative colony-forming unit (CFU)-GM, burst-forming unit-erythroid, and CFU-granulocyte erythroid macrophage megakaryocyte colonies from mock-infected, or the recombinant virus-infected cultures were subjected to polymerase chain reaction analysis using a neo-specific synthetic oligonucleotide primer pair. A 276-bp DNA fragment that hybridized with a neo-specific DNA probe on Southern blots was only detected in those colonies cloned from the recombinant virus-infected cells, indicating stable integration of the transduced neo gene. These studies suggest that parvovirus-based vectors may prove to be a useful alternative to the more commonly used retroviral vectors for high efficiency gene transfer into slow or noncycling primitive hematopoietic progenitor cells, without the need for growth factor stimulation, which could potentially lead to differentiation of these cells before transplantation.  相似文献   
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The pharmacokinetic and pharmacodynamic effects of vaginal rings releasing levonorgestrel (L-NOG) at an initial rate of 27 micrograms/24 h were studied in a group of 12 normally menstruating women during 90 days of continuous use (i.e., during three 30-day treatment segments). Blood samples were drawn immediately before insertion, 15 and 30 min, as well as 1, 2, 4, 8, 12 and 24 h after insertion of the rings, and thereafter three times weekly throughout the study for the analysis of L-NOG, estradiol, progesterone and sex hormone-binding globulin (SHBG). Endometrial biopsies were obtained for a morphometric analysis in a pre-treatment (control) cycle and in the 6th and 10th weeks of treatment. The peak of average L-NOG levels was reached within two hours after the insertion of rings. Until 24 h after insertion, the levels did not change significantly. Thereafter, a decrease at a rate of 0.2% per day was initiated. The L-NOG and SHBG levels were highly correlated. This was seen for both the pre-treatment SHBG vs L-NOG (r = 0.96) and the treatment SHBG vs L-NOG levels (r = 0.92). There was a significant (p < 0.001) decrease of SHBG levels due to treatment. During the total of 36 treatment segments, a normal ovarian function was seen in 47% of the segments. The women were anovulatory and had an inadequate lutal function in 28% and 25% of segments, respectively. No correlation between the L-NOG levels and ovarian reaction to treatment was found. The use of L-NOG induced significant changes in the endometrium; the number of glands/mm2 decreased after 6 (p < 0.02) and 10 weeks of use (p < 0.01). Also, the diameter of glands and the occurrence of vacuolated cells decreased significantly (p < 0.02 and p < 0.005, respectively). None of the endometrial parameters or dating was correlated with the ovarian reaction to treatment, indicating independent endometrial effects of L-NOG.  相似文献   
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Darier's disease (DD) is an autosomal dominant genodermatosis characterized by epidermal acantholysis and dyskeratosis. We have performed genetic linkage studies in 10 families with DD (34 affected) by analyzing 14 polymorphic microsatellite markers. Our results confirm recent reports mapping the DD gene to chromosome 12q23-q24.1. Haplotype analysis of recombinant chromosomes in our families, along with previously reported data, narrow the location of the DD gene to a 5 cM interval flanked by the loci D12S354 and D12S84/D12S105. This localization allowed exclusion of two known genes, PLA2A and PAH, as candidate loci for DD. Three other gene loci (PPP1C, PMCH, PMCA1), mapping in 12q21-q24, remain potential candidates.  相似文献   
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The hematologic abnormalities of SIV and HIV are well described, although the mechanisms that lead to hematopoietic dysfunction are yet to be fully defined. A number of growth factors and cytokines have been used to induce the differentiation, maturation, and proliferation of appropriate lineages, with the aim that such therapy will lead to functional hematopoietic reconstitution. Within this context, some cytokines have been shown to influence HIV and SIV replication in vitro and, in selected cases, in vivo. However, few studies detail the effects of hematopoietic cytokines such as IL-3, Flt-3 ligand, G-CSF, Tpo, and Epo or correlate the effects on virus replication. In an effort to address this issue, we infected 12 rhesus macaques with 500 TCID50 of SIVmac239 and intensively evaluated hematologic, virologic, and immunologic parameters during administration of cytokines. When all animals had lymphadenopathy, hepatosplenomegaly, and CD4+ cell counts > or =1000/microl, subgroups of three rhesus macaques were administered either rhFlt-3; rrIL-3a; combination of rhG-CSF, rhTpo, and rhEpo (rhGET); or rrIL-12. Fourteen days of rhFlt-3 administration induced expansion of the bone marrow CD34+ cells and granulocyte-macrophage colony-forming units (GM-CFUs) and increased absolute peripheral blood CD34+ cells and total CFUs. Following rrIL-3 and rhGET administration absolute peripheral blood CD34+ cells and total CFUs increased. rhGET also increased granulocyte, platelet, and reticulocyte counts by day 14 of administration. Branched DNA and coculture assays did not demonstrate any significant change in viral load with any of the cytokines administered. These data suggest that SIV-infected rhesus macaques have the hematopoietic capability to expand and mobilize CD34+ and GM-CFU progenitors and formed elements at 6-8 months postinfection in response to various cytokines, without increasing viral load.  相似文献   
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