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1.
Migration of Kirschner (K) wires from the upper extremity joints has often been reported, but it is less common from the lower extremities. In this report, we describe an 85-year-old man treated, during a hip replacement procedure, with a K-wire because of a trochanteric fracture; after one year, the K-wire was found in the popliteal fossa. This report illustrates the first case of K-wire migration in the popliteal area of the knee and suggests avoiding the use of free K-wires without any tension banding.  相似文献   
2.
Conjugation pathways in liver disease.   总被引:2,自引:2,他引:0       下载免费PDF全文
1. The activities of microsomal glucuronyltransferase and thiomethyltransferase, and those of cytosolic sulphotransferase, acetyltransferase, glutathione transferase and thiomethyltransferase were measured in abnormal (cirrhosis and chronic hepatitis) and normal livers. 2. Glucuronyltransferase and sulphotransferase were investigated with 2-naphthol and ethinyloestradiol as substrates. p-Aminobenzoic acid, benzo(a)pyrene-4,5-epoxide and 2-mercaptoethanol were the substrates of acetyltransferase, glutathione transferase and thiomethyltransferase, respectively. 3. Enzyme activities are expressed as nmol min-1 incubation mg-1 protein and the averages (+/- s.d.) are given. With 2-naphthol as substrate, the glucuronyltransferase activity was 6.55 +/- 4.10 (abnormal liver, n = 33) and 7.81 +/- 4.02 (normal liver, n = 26) (NS); whereas sulphotransferase activity was 0.28 +/- 0.18 (abnormal liver, n = 35) and 0.68 +/- 0.43 (normal liver, n = 26) (P less than 0.01). Glucuronyltransferase activity towards ethinyloestradiol was 102.5 +/- 56.9 (abnormal liver, n = 30) and 107 +/- 59.9 (normal liver, n = 26) (NS), whereas sulphotransferase activity was 57.2 +/- 36.0 (abnormal liver, n = 35) and 122 +/- 67.6 (normal liver, n = 28) (P less than 0.01). Acetyltransferase activity was 0.84 +/- 0.83 (abnormal liver, n = 35) and 3.84 +/- 1.65 (normal liver, n = 26) (P less than 0.01). Glutathione transferase activity was 0.83 +/- 0.68 (abnormal liver, n = 35) and 2.90 +/- 1.59 (normal liver, n = 25) (P less than 0.01) and thiomethyltransferase activity was 1.00 +/- 0.69 (abnormal liver, n = 34) and 3.99 +/- 1.49 (normal liver, n = 25) (P less than 0.01). 4. Liver disease lowers the activities towards the substrates studied of sulphotransferase, acetyltransferase, glutathionetransferase and thiomethyltransferase but not that of glucuronyltransferase.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
3.
Attenuation correction (AC) for myocardial perfusion SPECT (MPS) had not been evaluated separately in women despite specific considerations in this group because of breast photon attenuation. We aimed to evaluate the performance of AC in women by using automated quantitative analysis of MPS to avoid any bias. METHODS: Consecutive female patients--134 with a low likelihood (LLk) of coronary artery disease (CAD) and 114 with coronary angiography performed within less than 3 mo of MPS--who were referred for rest-stress electrocardiography-gated 99mTc-sestamibi MPS with AC were considered. Imaging data were evaluated for contour quality control. An additional 50 LLk studies in women were used to create equivalent normal limits for studies with AC and with no correction (NC). An experienced technologist unaware of the angiography and other results performed the contour quality control. All other processing was performed in a fully automated manner. Quantitative analysis was performed with the Cedars-Sinai myocardial perfusion analysis package. All automated segmental analyses were performed with the 17-segment, 5-point American Heart Association model. Summed stress scores (SSS) of > or =3 were considered abnormal. RESULTS: CAD (> or =70% stenosis) was present in 69 of 114 patients (60%). The normalcy rates were 93% for both NC and AC studies. The SSS for patients with CAD and without CAD for NC versus AC were 10.0 +/- 9.0 (mean +/- SD) versus 10.2 +/- 8.5 and 1.6 +/- 2.3 versus 1.8 +/- 2.5, respectively; P was not significant (NS) for all comparisons of NC versus AC. The SSS for LLk patients for NC versus AC were 0.51 +/- 1.0 versus 0.6 +/- 1.1, respectively; P was NS. The specificity for both NC and AC was 73%. The sensitivities for NC and AC were 80% and 81%, respectively, and the accuracies for NC and AC were 77% and 78%, respectively; P was NS for both comparisons. CONCLUSION: There are no significant diagnostic differences between automated quantitative MPS analyses performed in studies processed with and without AC in women.  相似文献   
4.
Conclusion  We would like to stress that we do not necessarily consider AC for SPECT MPI to be unfeasible or unworthy of scientific pursuit; indeed, a great deal of creative scientific effort has been poured into this area of investigation over the past 3 decades, and much of it has contributed to a better understanding of the physics, as well as the clinical aspects, of our field. However, the great variety of available AC hardware and software “flavors,” the historical pattern of commercial release of insufficiently validated AC implementations, and the increasingly clouded health care reimbursement horizon may have created an environment where the envisioned users of the technology have been desensitized and discouraged from expecting it to ever come to fruition in a standardized, validated, and costeffective form. It has been reported as recently as 2005 that the “entire base of SPECT cameras has only 5% of systems with attenuation correction.”8 Perhaps the reports of AC’s demise are exaggerated, but it certainly seems as if the people have spoken and, after readying themselves for the wolf one too many times, have come to the conclusion that “the future (of AC) ain’t what it used to be” . . .at least not yet.  相似文献   
5.
1. KCl, carbachol, neurokinin A and endothelin produced concentration-dependent contractions of mucosa-free muscle strips from the dome of the human urinary bladder. The maximal response to carbachol or neurokinin A exceeded that to KCl, while the maximal response to endothelin approached that to KCl. 2. Nifedipine (1 microM) abolished the response to KCl, reduced the response to carbachol or neurokinin A but had no effect on the response to endothelin. Bay K 8644 (1 microM) markedly potentiated the response to KCl but had little or no effect on the response produced by the other stimulants. 3. Superfusion of the strips with a nominally calcium (Ca)-free medium containing EDTA (1 mM) for 30 min markedly reduced the response to carbachol, neurokinin A and endothelin, although a small response was still evident at high concentrations. Likewise, after a prolonged (60 min) superfusion of the strips with a high K (80 mM) Ca-free medium plus EDTA (1 mM) these three agonists still produced a small contractile response. 4. The nifedipine (1 microM) resistant response to carbachol, neurokinin A or endothelin was markedly depressed by LaCl3 (1 mM). In contrast, the nifedipine-(1 microM) resistant response to carbachol was not modified by NiCl2 (0.1 mM) or omega-conotoxin (0.1 microM). 5. Caffeine produced divergent effects depending upon the temperature of incubation: a relaxation at 37 degrees C and a concentration-dependent (2.5-20 mM) contraction at 25 degrees C. The latter was markedly inhibited by procaine (3 mM) but unaffected by nifedipine (1 microM). 6. After a prolonged (60 min) superfusion with a high K, Ca-free medium containing EDTA the response to carbachol (100 microM) was abolished by previous exposure to procaine (3 mM). Conversely, the response to endothelin (1 microM) was unaffected by procaine. The response to endothelin in these experimental conditions was also resistant to LaCl3 (1 mM). 7. These findings indicate that multiple sources of Ca are mobilized for contraction of the human bladder muscle by different stimulants. Dihydropyridine- and voltage-sensitive Ca channels provide the major if not the sole source of Ca for the response to KCl, play some role in the response to muscarinic (carbachol) or NK-2 tachykinin receptor stimulation but are not involved in the response to endothelin. Carbachol, neurokinin A and endothelin all mobilize a Ca pool (either extracellular or located at membrane level) which is LaCl3-sensitive but nifedipine-resistant. Neither T- nor N-type channels appear to be involved in the response to carbachol.(ABSTRACT TRUNCATED AT 400 WORDS)  相似文献   
6.
7.
Summary The chromophore-modified derivative of doxorubicin, 4-demethyl-6-0-methyl-doxorubicin, has been tested for antitumor activity in a range of experimental murine tumor systems. In contrast to the inactive 6-0-methyl derivative of daunorubicin, 4-demethyl-6-0-methyl-doxorubicin provided antitumor effects comparable to that of the parent compound. In addition, detailed DNA-interaction studies showed that the doxorubicin derivative retains the ability to bind DNA by the intercalation mechanism. However, the binding affinity was appreciably reduced following structural modification in the anthraquinone chromophore. On the basis of the proposed models of intercalation, these results could be rationalized in terms of steric influence of the bulky methoxy group. The results of this study are in agreement with the correlation already observed between DNA binding and relative antitumor activity of anthracyclines.  相似文献   
8.
Chronic expanding intracerebral hematoma   总被引:21,自引:0,他引:21  
The cases of 10 normotensive patients with chronic intracerebral hematomas are reported. The patients' median age at diagnosis was 42 years. The median duration of symptoms was 22 days. Seizures were the presenting symptom in 50% of the cases. Computerized tomography almost consistently demonstrated ring-shaped lesions with mass effect and perifocal edema. Arteriography revealed that all but one of the lesions were avascular. All patients had superficial white matter lesions, mostly in the frontoparietal region. All patients were treated surgically. Most of the hematomas were encapsulated and contained blood in various stages of organization. The thick capsule consisted of an outer layer of collagenous tissue and an inner layer of granulation tissue. Occult cerebrovascular malformations were detected in two instances. There were two deaths, both related to recurrent postoperative hemorrhage. This entity can present much like a brain malignancy and should be considered in the differential diagnosis of ring-shaped lesions whatever the clinical presentation. Strategies of treatment are discussed.  相似文献   
9.
The effect of systemic administration of Ruthenium Red on the excitatory and desensitizing effect of capsaicin was investigated in rats. Ruthenium Red was injected s.c. 30 min before capsaicin was administered. The excitatory effect of capsaicin on corneal, perivascular and visceral afferents was not influenced by treatment with Ruthenium Red. However, determination of the neuropeptide content and evoked neuropeptide release in peripheral organs and dorsal spinal cord 48 h after treatment showed that Ruthenium Red attenuated the 'desensitizing' effect of capsaicin at peripheral, but not at central, endings of primary afferents. On the other hand, a capsaicin-elicited autonomic reflex mediated by visceral afferents was still obtained in 9 of 14 rats that had received Ruthenium Red and capsaicin. The results indicate that a single dose of Ruthenium Red, which does not reduce the acute excitatory effect of capsaicin, reduces the desensitizing effect of capsaicin on peripheral endings of primary afferents in vivo. This long-lasting protective effect of Ruthenium Red suggests that it is possible to pharmacologically differentiate between the acute and chronic effects of capsaicin.  相似文献   
10.
It was shown that Dacarbazine and other triazene compounds render murine leukemias highly immunogenic and susceptible to natural immunity (NI). In addition a pilot clinical study revealed that Dacarbazine can be cytotoxic for bone marrow blasts in patients with acute non-lymphoblastic leukemias through a mechanism that could be, at least in part, of immunological origin. However triazenes depress antigen-dependent responses and NI, whereas interferons, including interferon-beta (IFN), antagonize drug-induced impairment of NI. Therefore the complex interaction between triazenes and IFN on NI effector (i.e. NK) lymphocytes and human target lymphoblastoid cells has been investigated. the results show that: (a) EFN increases NK activity and antagonizes the depressive effects of methyl-triazene-benzoic acid (MTBA, an in vitro active triazene compound) on the NK function; (b) a lymphoblastoid cell line exposed to multiple in vitro treatments with MTBA, shows increased growth rate, augmented chemoresistance to MTBA, and higher susceptibility to NI than parental cells; (c) as expected IFN pretreatment down-regulates the susceptibility of lymphoblastoid cells to NK effectors; (d) however a net “therapeutic gain” was found if the overall influence of MTBA + IFN on target and effector cells is considered.  相似文献   
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