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Summary Hypodermic needle shields may be used as tip protectors for several types of microsurgical instruments. These provide an inexpensive alternative to commercially available tip covers. 相似文献
13.
Pilot study to enhance HIV care using needle exchange-based health services for out-of-treatment injecting drug users 总被引:2,自引:0,他引:2
Altice Frederick L. Springer Sandra Buitrago Marta Hunt David P. Friedland Gerald H. 《Journal of urban health》2003,80(3):416-427
The introduction of highly active antiretroviral therapy (HAART) has resulted in marked reductions in mortality and acquired
immunodeficiency syndrome (AIDS) incidence across all risk groups; however, the proportionate decrease among injecting drug
users (IDUs) has been less impressive. Much of the disparity in benefit to IDUs has been a consequence of decreased access
to and receipt of potent antiretroviral combinations. Strategies to increase access to and utilization of HAART have included
entry into drug treatment and abstinence. Unfortunately, as few as 15%–20% of active drug users in the United States, and
in many other countries, are in drug treatment at any one time. We report a pilot project among out-of-drug treatment IDUs
infected with human immunodeficiency virus (HIV); HIV therapy was successfully provided to active heroin injectors using the
Community Health Care Van (CHCV) at sites of needle exchange. Subjects were willing to initiate, but were not receiving, recommended
HIV therapy and were not interested in formal drug treatment. Antiretroviral therapy regimens were selected and linked to
heroin injection timing. Weekly visits were scheduled by CHCV staff to assess adverse side effects and encourage adherence.
Of the 13 participants, the mean baseline HIV-1 RNA level and CD4 lymphocyte count were 162,369 (log 5.21) copies per milliliter
and 265 cells per milliliter, respectively. By 6 months, the proportion whose HIV-1 RNA was below the limits of detection
(<400 copies/mL) was 85% (N=11); 77% (N=10) had nondetectable levels by 9 months. By 12 months, 54% (N=7) had a persistently
nondetectable viral load, and the net increase in CD4 lymphocyte count was 150 cells per milliliter. As an additional and
unintended benefit of this pilot project, 9 (69%) subjects chose to enter drug treatment after achieving a nondetectable viral
load. Entry into drug treatment was associated with durability of viral suppression. This small pilot study suggests that
health services based on needle exchange may enhance access to HAART among out-of-treatment HIV-infected IDUs. In addition,
it demonstrates that this population can benefit from this therapy with the support of a nontraditional, community-based health
intervention. 相似文献
14.
The Ysc-Yop type III secretion (TTS) system allows extracellular Yersinia bacteria, adhering to eukaryotic target cells, to inject Yop effector proteins in the cytosol of these cells. The secretion apparatus, called the injectisome, ends up with a needle-like structure made of YscF. YopN, one of the proteins secreted by the injectisome is thought to act as a plug. YopB, YopD and LcrV, three other proteins secreted by the injectisome and called 'translocators' form a pore allowing translocation of the Yop effectors across the target cell plasma membrane. Here, we tested the role of LcrV, YscF and YopN in the formation of this pore in macrophages by monitoring the release of the low-molecular-weight fluorescent dye BCECF (2',7'-bis-(2-carboxyethyl)-5-(and-6)-carboxyfluorescein, acetoxymethyl ester, 623Da) and of the high-molecular-weight lactate dehydrogenase (LDH, 135 kDa). BCECF is released through the translocation pore itself provided no Yop effector is trafficking through the channel. In contrast, LDH is released by the osmotic lysis of the target cell that occurs after pore formation. This release is reduced by the GAP activity of YopE. In order to study the role of LcrV, one has to circumvent the regulatory effect of LcrV on the synthesis of YopB and YopD. We observed here that this regulatory role of LcrV is lost in a yopQ mutant and hence we studied the role of LcrV in a yopQ mutant background. A lcrV, yopQ double mutant was deficient in pore formation while able to produce YopB and YopD. Pore formation was restored by the introduction of lcrV(+) but not yopQ(+) confirming that LcrV itself is directly required for pore formation. Bacteria secreting only YopB, YopD and LcrV could form pores, showing that YopB, YopD and LcrV are sufficient for pore formation provided they are secreted by the same bacterium. LcrV is not involved in secretion of YopB and YopD as suggested previously. Bacteria producing normal Ysc injectisomes, including the YscF needle but no translocators did not form pores, indicating that the needle is not sufficient by itself for pore formation, as was also suggested. yopN mutant bacteria formed needles and released BCECF even if they secreted the effectors. This observation suggests that many translocation pores are not filled in the absence of YopN and thus that YopN might form a link between the needle and the pore, guiding the effectors. 相似文献
15.
目的探讨应用简易X线定位方法对乳腺隐匿性病灶切除的应用价值。方法在普通钼靶乳腺机上应用简易X线定位法,对31例乳腺隐匿性可疑病变进行病灶切除术前定位。结果30例一次定位成功,1例二次定位成功,定位满意度96.8%,病灶切除率为100%。结论简易X线定位方法可以指导临床准确切除病灶,并且安全可靠、价格低廉、创伤性小,具有临床应用价值。 相似文献
16.
Eighty-six fine-needle aspirates (FNAs) of pancreas from 74 patients were reviewed. Histological confirmation or clinical follow-up of the final diagnosis was available in 61 aspirates from 49 patients. Of 42 proven malignant cases, FNAs were diagnosed as positive in 21 (50%), suspicious in 4 (9.5%), negative in 12 (28.6%), and unsatisfactory in 5 (11.9%). Of 19 proven benign cases, FNAs were diagnosed as negative in 15 (78.9%) and unsatisfactory in 4 (21%). This resulted in a 50% sensitivity, a 100% specificity, a diagnostic efficiency of 59%, a predictive value of a positive test of 100%, and a predictive value of a negative test of 55.6%. Thirty-six primary pancreatic adenocarcinomas and six metastatic tumors to the pancreas were encountered. Benign cases were attributed to anatomical pancreatic variants, acute pancreatitis, abscess, chronic pancreatitis, and pseudocysts. Pancreatic FNA was safe, accurate, and relatively inexpensive, but it was relatively insensitive in the diagnosis of malignancy. 相似文献
17.
目的:探讨应用针形内窥镜对小儿鼻颅底疾病进行探查与手术的方法及疗效。方法:在外径1.9mm的进口针形内窥镜及电视同图像系统监视下,对8例小儿(7d ̄12岁)鼻颅底有关疾病进行探杳与手术。结果:先天性后鼻孔闭锁3例中,1例好转,3例痊愈。外伤性脑脊液鼻漏1例,经修补痊愈先天性脑膜脑膨出2例,确诊后1例暂缓治疗。另1例行内窥镜手术痊愈。颅底神经母细胞瘤2例取材作病理检查确诊。结论:在电视图像监视下应用 相似文献
18.
Background: The usefulness of transthoracoscopic needle biopsy for preoperatively indeterminate intrapulmonary nodules was evaluated.
Methods: Thoracoscopy was performed on 38 patients with pulmonary solitary nodules suspected to be primary lung carcinomas. When the
nodule was localized by simple observation or tactile sensor, a biopsy specimen of the tumor was obtained by a biopsy needle
introduced through a trocar.
Results: The nodules were 7 to 55 mm in diameter. All were located in the peripheral region of the lung. Biopsy specimens were obtained
even from 17 nodules with no associated pleural changes. By cytology, all the malignant tumors were precisely diagnosed, 29
as primary lung cancers and 3 as metastatic lung neoplasms. Five of the remaining six benign nodules were not precisely diagnosed.
However, they were cytologically classified as class I.
Conclusions: Transthoracoscopic needle biopsy is feasible for diagnosing small intrapulmonary nodules, particularly those of malignant
neoplasms. As compared with thoracoscopic excisional biopsy, transthoracoscopic needle biopsy saves time and may reduce the
possibility of tumor dissemination during the procedure.
Received: 14 March 1997/Accepted: 31 May 1997 相似文献
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