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71.
Coagulation and vascular abnormalities were studied in 4 patients with Crow-Fukase syndrome (CFS or POEMS) to understand the pathophysiology. Fibrinogen, fibrinopeptide A, and thrombin-antithrombin complexes (TAT) increased in sera during active phase of CFS. In nerves of 2 untreated cases, the endothelium of small vessels was immunohistochemically stained with antithrombin III antibody, which indicates the existence of TAT. HLA-DR+ inflammatory cell infiltrate surrounded these vessels. Blood-nerve barrier opening was suggested by strong immunoglobulin staining in the endoneurium. More than 50% of endoneurial blood vessels had narrowed or closed lumina with thick basement membranes. Endothelial cell abnormality and chronic intravascular coagulation may play an important role in the pathogenesis of CFS, in addition to a still unknown demyelinating factor. Refractory cases responded to combined treatment of prednisolone, human leukocyte interferon, and antithrombin drug.  相似文献   
72.
Petennann [1] computed an "excess spontaneous emission factor" for gain-guided laser. In this paper, we investigate further the role of this factor. Such a factor also appears in the treatment of thermodynamic equilibrium in an attenuating medium-a seeming paradox. Further investigation shows that the excess spontaneous emission excitation at thermal equilibrium is cancelled by the excitations in the other modes which are correlated with that in the fundamental mode. In a medium with gain, cancellation also occurs in a short amplifier in which there is no gain discrimination among modes. The "excess spontaneous emission factor" is fully present only in a system in which the different higher order modes have an appreciably smaller gain than the lowest order mode, a high gain amplifier. An analysis of the signal-to-noise ratio of a high gain amplifier reveals that the excess noise factor can be fully compensated by proper input excitation by a lens arrangement. The lens arrangement provides the signal with an "excess gain" factor. An "excess gain" factor is also present when a thermal source is used.  相似文献   
73.
Summary Hydro- and vinyl-bifunctionalized di- or tetrasiloxane were synthesized by degradative cleavage of functional cyclic siloxanes with methyllithium followed by quenching with a functional chlorosilane, or by ring-opening of hexamethylcyclotrisiloxane (D3) by functional alkyllithium followed by quenching with a functional chlorosilane. These bifunctionalized siloxanes were used as monomers in polyaddition with transition metal catalysts.  相似文献   
74.
STUDY OBJECTIVE: To evaluate the long-term efficacy of laparoscopic Burch urethropexy. DESIGN: Pilot study. SETTING: Private practice. PATIENTS: Thirty-five consecutive women (average age 45.5 yrs, average parity 2.3, average weight 67.7 kg) treated for genuine stress incontinence between May 1992 and July 1994. INTERVENTIONS: Urethropexy was performed with curved needle suturing in 7 women, straight needle suturing in 5, and Stamey needle suturing in 23. Twenty-five (71.4%) patients had concomitant pelvic surgery. MEASUREMENTS AND MAIN RESULTS: Wilcoxon two-sample, chi2, and Fisher's exact tests were performed to determine which variables were significantly associated with surgical success. Average operating time was 190 minutes, hospitalization 24 hours, and catheterization 5 days. The cure rate of stress incontinence was 89% 3 months and 86% 1 year after surgery. At average follow-up of 34 months, only 68.6% of patients reported complete or almost complete cure, 11.4% were improved, and 20% were complete failures. The only operative variable approaching statistical significance for predicting surgical success was type of suture needle (p = 0.07), with the Stamey needle group having the highest cure rate. Women who were cured or almost cured had a significantly shorter follow-up than those who were improved or failures (p = 0.001). CONCLUSION: The success rate of laparoscopic Burch urethropexy compares with that of open Burch procedure at 1 year, but drops considerably thereafter.  相似文献   
75.
Accurate measurement of the cross-section of the 12C(α, γ)16O reaction is very important in nuclear astrophysics. Enriched 12C targets prepared with the high energy vibrationl powder plating [HIVIPP] method for this purpose have been used successfully. Initially, however, the 12C deposits for studying this small cross-section partially peeled from their Au backings when irradiated with beam currents≥2 times the 7 μA pulsed α-beam used previously. This problem was solved when the amorphous 12C powders were converted to graphite by heat-treatment in a high-temperature furnace. We investigated powder heat treatments at temperatures of 2600-3500 °C to reveal, which conditions resulted in uniform and highly adhesive depositions on Au backings.  相似文献   
76.
Changes made in 1997 and 1998 in the U.S. childhood immunization schedule are discussed, with a focus on the use of poliovirus, pertussis, and combination vaccines. Oral poliovirus vaccine (OPV), the vaccine of choice for all four doses in the polio immunization series since 1962, can cause vaccine-associated paralytic poliomyelitis (VAPP). The inactivated poliovirus vaccine (IPV) has not been associated with VAPP but must be administered by injection and provides inferior intestinal immunity. With the reduced threat of poliovirus importation into the United States, the risk of VAPP, although low, has become less acceptable. The Centers for Disease Control and Prevention accordingly recommended a shift from OPV to IPV in the childhood immunization schedule for the United States, effective January 1997. A sequential OPV and IPV series is recommended, but the schedule includes an OPV-only option, which may be preferred in order to avoid the required injections, and an IPV-only option, which is recommended for immunocompromised persons and their contacts. Concern over local and systemic reactions associated with whole-cell pertussis vaccines, in addition to controversy over a possible relationship between the whole-cell vaccine and neurologic damage, has led to the development of new diphtheria and tetanus toxoids and acellular pertussis vaccine products for use in the diphtheria and tetanus toxoids and pertussis immunization series. Several combination products were licensed in 1997, and more are on the way. This will mean fewer inoculations for children. Increased use of IPV and acellular pertussis products could reduce the frequency of VAPP due to OPV and the local and systemic reactions associated with whole-cell pertussis vaccine.  相似文献   
77.
The nitriding rate in a plated invar with an Fe-Ni-Cr alloy (face-centred cubic) layer were compared by optical microscopy with the rate in an unplated invar. In the plated invar rapid nitrogen diffusion was discovered. The plated layer plays a role in enhancing the nitriding rate. The result gives a solution for an abnormal enhancement nitriding rate in austenitic stainless steels. The enhancement is explained from the viewpoint of non-equilibrium thermodynamics.  相似文献   
78.
Threshold photoelectron spectra of N2+ were measured between 23.4 and 27.6 eV with high resolution and high intensity by using the penetrating field technique and synchrotron radiation. Five vibrational progressions were observed. The first of these progressions was the C2Sigmau+ state. The second progression was identified as the transition to the second state of 2Pig symmetry found by P. Baltzer, M. Larsson, L. Karlsson, B. Wannberg, and M. Carlsson (1992. Phys. Rev. A 46, 5545). The third progression, which was discovered by F. Merkt and P. M. Guyon (1993. J. Chem. Phys. 99, 3400), can be designated as the 2Sigmau- state by comparison with previous theoretical study (E. W. Thulstrup and A. Andersen, 1975. J. Phys. B 8, 965). The fourth and fifth progressions were designated as the 2Deltau and 2(2) Piu states by similar comparison with previous theories. Copyright 1997 Academic Press. Copyright 1997Academic Press  相似文献   
79.
We previously established a limited sampling model (LSM) for the area under the concentration versus time curve (AUC) of irinotecan (CPT-11). Using this LSM, we performed a pharmacokinetic-pharmacodynamic analysis of CPT-11 in a multicentric Phase II study for non-small cell lung cancer. Ten institutes participated in this study, 36 patients were registered, and 30 patients were evaluable for the pharmacokinetic-pharmacodynamic analysis. CPT-11 and etoposide were administered daily for three consecutive days, both at a dose of 60 mg/m2. Blood samples were obtained 4 and 8 h after infusion on days 1 and 3. When using the LSM, there is a significant possible source of error in the timing of these selected points. In this study, however, the sample timing error was small. Mean timing errors were 1.0-4.0 min at each point. The estimated CPT-11 AUCs were: Day 1 Day 2 Day 1 + 3 Mean +/- SD (mg.h/liter) 3.76+/-0.68 4.10+/-0.86 7.86+/-1.43 Range 2.01-5.03 2. 29-5.72 4.30-10.68 Max/min 2.50 2.45 2.48 High interpatient variability was observed in the AUC. The CPT-11 AUC correlated positively with the grade of emesis (P = 0.003) and the percent decreases in WBC count (P = 0.001) and absolute neutrophil count (P =0.0006), but it did not correlate with the grade of diarrhea or response. We concluded that the LSM was useful in estimating individual pharmacokinetic parameters in multicentric trials.  相似文献   
80.
The aim of this study was to estimate the incidence of melanoma in the Paris region in 1994 and analyse the main clinical and histological characteristics of these lesions. It took the form of a prospective inquiry, mailed to public and private pathology laboratories, to count as accurately as possible the number of new cases diagnosed by pathologists in the region during the 1994 calendar year. In all, 1089 newly diagnosed Clark level I to V melanomas (excluding precancerous melanosis of Dubreuilh) were studied. Parameters recorded included age, sex, Clark level and Breslow's thickness. The incidence per 100,000 inhabitants was 9.93 for melanoma and 8.62 for invasive melanoma. The female to male ratio was 1.6. Clark level I or thin (< 0.75 mm) melanomas represented 64.8% of the lesions. At the time of diagnosis, the females were significantly younger than the males (P = 0.004). Breslow's thickness increased with age and was significantly lower in women (P = 0.00005), especially those between 40 and 49 years old. The incidence of melanoma in the Paris region in 1994 was close to that observed during the preceding 5 years in England, Scotland and the French department of Haut-Rhin. It was 2.32 times higher for males and 1.69 times higher for females than the rates estimated for France for the period 1978-1982.  相似文献   
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