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31.
Soft tissue sarcomas are unusual malignancies comprising 1% of cancer diagnoses in the United States. Undifferentiated pleomorphic sarcoma accounts for approximately 5% of sarcomas occurring in adults. The most common site of metastasis is the lung, with other sites being bone, the brain, and the liver. Metastasis to the gastrointestinal tract has rarely been documented. We present an unusual case of high-grade pleomorphic sarcoma with metastasis to the stomach, complicated by upper gastrointestinal bleedin...  相似文献   
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Background contextMultilevel lumbar disc disease (MLDD) is a common finding in many patients. Surgical solutions for MLDD include fusion or disc replacement. The hybrid model, combining fusion and disc replacement, is a potential alternative for patients who require surgical intervention at both L5–S1 and L4–L5. The indications for this hybrid model could be posterior element insufficiency, severe facet pathology, calcified ligamentum flavum, and subarticular disease confirming spinal stenosis at L5–S1 level, or previous fusion surgery at L5–S1 and new symptomatic pathology at L4–L5. Biomechanical data of the hybrid model with the Maverick disc and anterior fusion are not available in the literature.PurposeTo compare the biomechanical properties of a two-level Maverick disc replacement at L4–L5, L5–S1, and a hybrid model consisting of an L4–L5 Maverick disc replacement with an L5–S1 anterior lumbar interbody fusion using multidirectional flexibility test.Study designAn in vitro human cadaveric biomechanical study.MethodsSix fresh human cadaveric lumbar specimens (L4–S1) were subjected to unconstrained load in axial torsion (AT), lateral bending (LB), flexion (F), extension (E), and flexion-extension (FE) using multidirectional flexibility test. Four surgical treatments—intact, one-level Maverick at L5–S1, two-level Maverick between L4 and S1, and the hybrid model (anterior fusion at L5–S1 and Maverick at L4–L5) were tested in sequential order. The range of motion of each treatment was calculated.ResultsThe Maverick disc replacement slightly reduced intact motion in AT and LB at both levels. The total FE motion was similar to the intact motion. However, the E motion is significantly increased (approximately 50% higher) and F motion is significantly decreased (30%–50% lower). The anterior fusion using a cage and anterior plate significantly reduced spinal motion compared with the condition (p<.05). No significant differences were found between two-level Maverick disc prosthesis and the hybrid model in terms of all motion types at L4–L5 level (p>.05).ConclusionThe Maverick disc preserved total motion but altered the motion pattern of the intact condition. This result is similar to unconstrained devices such as Charité. The motion at L4–L5 of the hybrid model is similar to that of two-level Maverick disc replacement. The fusion procedure using an anterior plate significantly reduced intact motion. Clinical studies are recommended to validate the efficacy of the hybrid model.  相似文献   
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Clinical studies suggest that chemotherapy is associated with long-term cognitive impairment in some patients. A number of underlying mechanisms have been proposed, however, the etiology of chemotherapy-related cognitive dysfunction remains relatively unknown. As part of a multifaceted approach, animal models of chemotherapy-induced cognitive impairment are being developed. Thus far, the majority of animal studies have utilized a rat model, however, mice may prove particularly beneficial in studying genetic risk factors for developing chemotherapy-induced cognitive impairment. Various chemotherapy agents, including cytosine arabinoside (Ara-C), have been found to impair remote spatial memory in rats in the Morris water maze. The present study evaluated the effects of Ara-C on remote (30 d) spatial memory in mice. In addition, the possibility that time relative to chemotherapy treatment may modulate the effect of chemotherapy on spatial learning and/or recent (1 d) memory was explored. Male C57BL/6J mice received either Ara-C (275 mg/kg i.p. daily for 5 days) or saline. Spatial learning and memory was assessed using the Morris water maze. Half the mice performed a remote (30 d) memory version of the task and the other half performed a recent (1 d) memory version of the task. The experiment was designed such that the probe trial for the recent memory version occurred on the same day relative to chemotherapy treatment as the remote memory version. Despite significant toxic effects as assessed by weight loss, Ara-C treated mice performed as well as control mice during acquisition, recent memory, and remote memory portions of the task. As are some humans, C57BL/6J mice may be resistant to at least some aspects of chemotherapy induced cognitive decline.  相似文献   
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Functional and structural studies demonstrate that Cl channels of the ClC family have a dimeric double-barrelled structure, with each monomer contributing an identical pore. Studies with ClC-0, the prototype ClC channel, show the presence of independent mechanisms gating the individual pores or both pores simultaneously. A single-point mutation in the CBS-2 domain of ClC-0 has been shown to abolish slow gating. We have taken advantage of the high conservation of CBS domains in ClC channels to test for the presence of a slow gate in ClC-2 by reproducing this mutation (H811A). ClC-2-H811A showed faster opening kinetics and opened at more positive potentials than ClC-2. There was no difference in [Cl]i dependence. Additional neutralization of a putative pore gate glutamate side chain (E207V) abolished all gating. Resolving slow and fast gating relaxations, however, revealed that the H811A mutation affected both fast and slow gating processes in ClC-2. This suggests that slow and fast gating in ClC-2 are coupled, perhaps with slow gating contributing to the operation of the pore E207 as a protopore gate.  相似文献   
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The development of an addiction considerably damages physical health, social functioning, and quality of life; however, people with substance use disorders act as if they were unaware of how drug and alcohol use contribute to their difficulties. This is one of the main reasons why they fail to address the problem and remain in a self-destructive spiral. The aim of this study was to construct and validate a diagnostic questionnaire for detecting an individual’s level of awareness of drug use, its consequences, and associated illnesses. Three sequential phases were carried out: theoretical (construction and production of adequately worded items), experimental (administration of the questionnaire to a sample of 124 patients with a substance use disorder), and analytical (factor analysis, temporal and internal reliability, discriminant validity, and sensitivity to change during treatment). The ICE-A showed a one-dimensional structure (all the items that make up the questionnaire measure a single variable that can be presented as a total score), an adequate level of internal consistency, and high temporal stability over a 1-month period. The scores obtained by the subjects at 12 months of treatment were significantly higher than those obtained by the same subjects at 6 months of treatment. This questionnaire could allow therapists to monitor the psychotherapeutic processes and outcomes of their addicted patients, assuming that the greater their awareness of their disease, the greater their self-care and improvement.

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OBJECTIVES: The goals of this laboratory model were to evaluate the performance of the surgical team and endolaparoscopic techniques in the porcine model of infrarenal abdominal aortic repair. METHODS: Twenty-four pigs underwent full endolaparoscopic aorto-aortic graft implantation with voice-activated computerized robotics. The first group of 10 pigs (acute) was sacrificed while under anesthesia at 0.5 hours (5 animals) and 2 hours (5 animals). The second group of 14 pigs (survival) were recovered from anesthesia and maintained for 7 hours (5 pigs) and 7 days (9 pigs) prior to sacrifice. Survival animals were observed for evidence of hind limb dysfunction. All grafts were visually inspected at autopsy. RESULTS: All animals survived the operation. All grafts were successfully implanted, and all were patent with intact anastomoses at autopsy. Mean aortic clamp time for each group was as follows: acute, 92.9 +/- 28.04 minutes; survival, 59.6 +/- 13.8 minutes; P=0.0008. Total operative time for each group was as follows: acute, 179 +/- 39.6 minutes; survival, 164.6 +/- 48 minutes; P=0.44 ns. Estimated blood loss for each group was as follows: acute, 214 -/+ 437.8 mL; survival 169.2 +/- 271 mL; P=0.76 ns. from respiratory arrest; 1 animal suffered motor sensory dysfunction of the hind limbs (spinal cord ischemia); significant bleeding occurred in 6 of 24 pigs; 8 of the 9 seven-day survivors required minimal pain medication and had normal hind limb function. CONCLUSIONS: The reduction in aortic clamp time, total operative time, and blood loss as the study progressed indicate the feasibility of this surgical protocol and the maturation of the learning process, which is paramount in prevention of 2 main sources of morbidity: bleeding and spinal cord ischemia. The reduction in aortic clamp time between the acute and survival groups was dramatic and statistically significant. An intensive formal training program combining dry and live surgical laboratories is deemed essential for the development of endoscopic skill sets necessary for this challenging procedure.  相似文献   
39.
A substantial body of literature has characterized how psychosocial factors, including HIV-related stigma and coping, are associated with HIV testing and HIV care utilization post-diagnosis. Less is known about if certain psychosocial characteristics pre-diagnosis may also predict linkage to care among individuals who receive an HIV-positive diagnosis. We examined if pre-diagnosis awareness/perception about HIV-related stigma and dispositional coping styles predicted linkage to HIV care within three months post-diagnosis with a secondary analysis of 604 patients from a randomized controlled trial (Sabes Study). Awareness/perception about HIV-related stigma, dispositional maladaptive and adaptive coping were measured before patients underwent an HIV test. Linkage to care was measured as receipt of care within three months of receiving the diagnosis. After adjusting for covariates, individuals who reported greater dispositional maladaptive coping pre-diagnosis had lower odds of linking to care, OR?=?0.82, 95%CI [0.67, 1.00], p?=?.05. There was also a non-significant inverse association between dispositional adaptive coping pre-diagnosis and linkage to care. These preliminary data suggest the need for further longitudinal research and highlight the potential utility of pre-diagnosis psychosocial assessment and tailored counseling when providing positive HIV diagnosis results.  相似文献   
40.
Endoscopic resection of the submandibular gland in a porcine model   总被引:6,自引:0,他引:6  
OBJECTIVE: To examine the feasibility of endoscopic resection of the submandibular gland in a porcine model. STUDY DESIGN: Experimental, nonrandomized prospective study. METHODS: Twelve endoscopic submandibular gland resections were performed on seven Yorkshire adult pigs using a combination of balloon dissection and low-pressure CO2 insufflation. The operative time, blood loss, blood pressure, oxygen saturation, temperature, arterial blood gas values, and weight of the glands were measured. RESULTS: All 12 submandibular gland resections were successfully performed endoscopically, and no conversions to open resection were necessary. The procedures lasted 42 to 140 minutes (median duration, 59 min). The median estimated blood loss was 15 mL. The submandibular glands weighed 13.3 +/- 1.5 g. The arterial blood pH varied from a decrease of 0.08 to an increase of 0.09 units from the beginning to the end of the operation. Similarly, the arterial CO2 pressure at the end of the case varied from a decrease of 15.8 to an increase of 16.2 mm Hg from the starting value. The presence of normal glandular architecture and lack of trauma or thermal injury were confirmed histologically. There were no cases of pneumothorax or air embolism, and no animals had to be killed. In one animal, a modest amount of subcutaneous emphysema could be appreciated, which was confined to the area over the operative pocket. CONCLUSION: Endoscopic resection of the submandibular gland is possible by combining balloon dissection with low-pressure CO2 insufflation, thereby avoiding complications of high-pressure insufflation such as pneumothorax and air embolism.  相似文献   
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