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51.
HCVRNA阳性的丙型肝炎46例,均经临床和/或组织学确诊。治疗组24例用IFNa-nl或a-2b3×106IU,隔日一次;对照组22例用一般护肝药物。HCVRNA12周转阴率治疗组为83.3%,对照组为9.0%(P<0.001)。ALT和AST复常率治疗组也优于对照组(P<0.05)。随访观察满48周者治疗组15例中HCVRNA持续转阴11例(73.3%).对照组5例均持续阳性。治疗组中5例做了Ⅰ~Ⅲ型HCV基因分型,结果均为Ⅱ型。同时对急、慢性丙型肝炎的发病过程和病理诊断作了讨论。 相似文献
52.
Abstract: Lobular carcinoma in situ (LCIS) has gone from a rare form of mammary cancer to a marker of increased risk. Treatment options have undergone a corresponding change from ipsilateral mastectomy with axillary node dissection to observation once it became clear that the majority of patients did not progress to invasive cancer. However, recent events suggest a re-evaluation of LCIS management options. It is clear that even meticulous observation may fail to detect invasive cancer before systemic spread has taken place. This fact plus the identification of breast cancer genes have brought a renewed interest in prophylactic mastectomy. At the same time pathologists feel that it is possible to identify microscopic features of LCIS pointing to an increased likelihood of developing invasive cancer. As a result physicians are being asked to better quantitate risks for individual patients. Most patients with LCIS do not need bilateral mastectomies, but we are coming closer to identifying the minority that would be better served by prophylactic surgery. 相似文献
53.
F. Schmidt R. Stollberger M. Pedevilla J. Simbrunner K. Hartwagner F. Ebner 《European Surgery》1997,29(3):115-117
Zusammenfassung
Grundlagen: Der Zweck war es, die Anzahl der im Mammogramm entdeckten duktalen Carcinoma in situ (DCIS) und multizentrische Karzinome
aufzudecken. Die verschiedenen Methoden der Biopsie werden diskutiert.
Methodik: Rastermammographie (Fokus 0,3 mm) und hochaufl?sende Sonographie (7,5 bis 10 MHz) wurden bei Brustkrebspatientinnen eingesetzt.
Ergebnisse: Der Zeitraum der aufgelisteten Patientinnen erstreckt sich über 20 Jahre. Die Zahl der DCIS hat in den letzten Jahren zugenommen
und betr?gt nun 18%. Die Mammographie ist hoch sensitiv für Entdeckung von Mikrokalzifikationen. Die Spezifit?t ist gering.
Schlu?folgerungen: Die Anzahl der entdeckten DCIS ist in den letzten Jahren besonders angestiegen und wird auch noch weiter bei Verbesserung
der mammographischen Techniken ansteigen.
Diese Studie wurde vom Ludwig-Boltzmann-Institut für radiologisch-physikalische Tumordiagnostik unterstützt. 相似文献
54.
The in-vitro oestradiol (E2) and progesterone (P) production by corpora lutea (CL) obtained at sterilization from 30 untreated women and 43 women treated with norethisterone (NET) 300 micrograms daily was measured. The CL were obtained at different stages of the luteal phase in the untreated women [luteinizing hormone (LH) 0 to +3, n = 7; LH +4 to +7, n = 7; LH +8 to +11, n = 9; LH +12 to menses, n = 7] and on days LH +8 to +11 or cycle days 22 to 26 in the NET-treated women. In the treated women, four types of ovarian reaction were identified. Four women showed ovarian reaction Type A (completely inhibited ovarian activity), 14 women Type B (marked follicular activity, but no luteal function), 12 women Type C (normal follicular activity, followed by insufficient luteal function) and 13 women Type D (apparently normal follicular and luteal activity). The CL were incubated in Eagle's medium with and without stimulation by human chorionic gonadotrophin (HCG) for 2 and 4 h. In the untreated women, P and E2 production increased significantly with both incubation time and stimulation by HCG throughout the luteal phase, except in the late luteal phase (LH +12 to menses) where P increased (P less than 0.01) only after 4 h stimulation by HCG. The maximal production of P was found after 4 h incubation with HCG stimulation of CL tissue in the early-mid luteal phase (LH +4 to +7).(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
55.
56.
Analysis of in vivo short TE 1H spectra is complicated by broad baseline signal contributions and resonance line-shape distortions. Although the assumptions of ideal metabolite resonance line-shapes and slowly varying baseline signals can be used to separate these signals, the presence of broad or asymmetric line-shapes can invalidate this model. More complex line-shape models are computationally expensive or difficult to constrain, particularly for the low signal-to-noise commonly found for in vivo MR spectroscopic imaging applications. In this study, two time-domain models for fitting variable spectral line-shapes are examined, one using B-splines and another using summed sinusoids. The methods were verified using both phantom and human data, and Monte Carlo simulations were used to evaluate variations in calculated metabolite amplitudes due to interactions between the baseline and line-shape estimations. Additional studies investigated the use of prior line-shape information, obtained from either a water MRSI measurement or calculations from B(0) maps, to determine parameter starting values or optimization constraints. Both line-shape models showed the ability to fit the variety of line-shapes present in both the phantom and human MRSI data, with similar or improved accuracy over a Gaussian line-shape model; however, this improvement resulted in only minor improvement for the high-SNR phantom data and moderate improvements in regions with asymmetry for the fitted in vivo metabolite images. The use of prior line-shape information was of most benefit when applied toward setting optimization constraints but was of limited benefit when used to define initial starting values. 相似文献
57.
This retrospective analysis reviews the clinical experience of a major urban referral hospital with diffuse malignant pleural mesothelioma during the 14-year period from 1973 through 1986. Seventy-five cases of definite or equivocal mesothelioma were identified. There were four cases of primary malignant peritoneal mesothelioma, seven cases of benign fibrous mesothelioma, and 64 cases of diffuse malignant pleural mesothelioma. In 43 cases (67%) of diffuse malignant pleural mesothelioma, there was historic evidence of asbestos exposure. In 21 cases (33%), there was no known history of asbestos exposure. An increase in annual incidence of diffuse malignant pleural mesothelioma was observed over the study period, from three cases in 1973 to ten cases in 1986. Despite greater awareness of this disease, the diagnosis remains a difficult one to establish given the nonspecific symptoms, signs and radiographic appearance, variable histologic appearance, and poor diagnostic sensitivity and specificity of thoracentesis and closed pleural biopsy. Thoracotomy, thoracoscopy, and CT-guided needle biopsies gave higher yields and are the diagnostic measures of choice when diffuse malignant pleural mesothelioma is suspected. 相似文献
58.
右室梗死临床诊疗新进展 总被引:3,自引:0,他引:3
右室梗死过去只能在尸检时确诊。20世纪70年代以来,随着医师诊断水平和检测设备的不断进步,临床上已能在患者生病确诊右室梗死[1],现对国内有关资料综述如下,仅供同道参考。1右心室栓塞发病及研究进展右心室心肌梗死是指累及右心室壁的心肌梗死。临床上相对少见。尸检病例中,单独右心室梗死不到3%,左心室心肌梗死同时延伸至右心室者占43%[1]。按其梗死发生部位分为:右心室游离下壁;右心室游离前壁;右心室游离下壁、前壁及右心室乳头肌。受累部位取决于受损血管的来源,右心室前壁和前乳头肌由左前支和圆锥支供血,前者分支较多,一般不会全部阻… 相似文献
59.
Objective: To analyze quantitatively the synergistic and antagonistic effects of combined oxymatrine (OMT) and 5-fluorouracil (5-GU)
on a cell line of human liver cancer (HepG2) with median-effect principle in vitro. Methods: The median-effect principle and MTT method were used in the quantitative analysis of effects of the two drugs. Results: Cytotoxic activity of the individual drugs enhanced as drug concentration increased. As fa=0.41, a CI equal to 1 indicated
additivity; fa<0.41, a CI less than 1 indicated synergy; and fa>0.41, a CI greater than 1 indicated antagonism. The sequence
of administration did not influence the cytotoxic activity of the combined antitumor drugs. The ratio of drug concentration
was a factor that can influence the killing effect. Conclusion: The combined drugs interaction (CI<1) was synergistic at lower concentration and antagonistic at higher concentration. The
ratio of drug concentration is a factor that can influence the killing effect.
Biography: HE Song(1965–), male, doctor of medicine, associate professor, Chongqing Medical University, majors in gastroenterology. 相似文献
60.
Two-dimensional HOHAHA and ROESY nuclear magnetic resonance techniques are used to obtain complete proton resonance assignments and to perform a conformational investigation of the neuropeptide neurotensin (pGlu-Leu-Tyr-Glu-Asn-Lys-Pro-Arg-Arg-Pro-Tyr-Ile-Leu) in aqueous solution, methanol, and membrane-mimetic [deuterated sodium dodecylsulfate (SDS)] environments. Results suggest the absence of discernible elements of secondary structure in water and methanol. ROESY spectra confirm that Lys-Pro and Arg-Pro peptide bonds are all-trans, but that a significant population of cis Arg-Pro bonds arises in aqueous solution, which increases in the environment of SDS micelles. The conformational ensemble of the peptide is observed to narrow as it becomes bound through its cationic mid-region to SDS micelles, with the accompanying advent of local extended structure. The overall results indicate the inherent conformational flexibility of neurotensin, and emphasize the environmental dependence of conformation in peptides of medium length. 相似文献