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91.
A large-scale, randomised, multicentre single-blind clinical trial was conducted to assess the comparative efficacy and tolerance of ofloxacin, trimethoprim and co-trimoxazole in the treatment of uncomplicated urinary tract infection in general practice. A total of 1,069 patients from 76 centres across the UK were enrolled in the study, and randomised to one of the following treatment groups: ofloxacin (200 mg od), trimethoprim (200 mg bd) or co-trimoxazole (trimethoprim 160 mg and sulphamethoxazole 800 mg bd). Each patient received five days of medication. Clinically, ofloxacin was as effective as trimethoprim and co-trimoxazole. However, the bacteriological cure rate was significantly better for ofloxacin, with eradication of the initial causative pathogen by the end of treatment in 92% of patients in the ofloxacin group, compared with 81% for trimethoprim and co-trimoxazole (P = 0.0002). There was also a lower relapse rate for ofloxacin. Ofloxacin was well tolerated: adverse events were reported by 67 (12.4%) patients in the ofloxacin group, compared with 48 (18.7%) patients in the co-trimoxazole group and 37 (13.6%) patients in the trimethoprim group. Ofloxacin can therefore be considered a suitable alternative for the treatment of uncomplicated urinary tract infection.  相似文献   
92.
An efficient method for the synthesis of 3-functionalized quinolines from commercially available acetophenones and anthranil has been described. Selectfluor propels the C(sp3)–H bond activation of the acetophenones and aza-Michael addition of anthranil resulting in annulated 3-acylquinolines in moderate to high yields. DMSO acts not only as a solvent but also as a one carbon donor in the reaction.

An efficient method for the synthesis of 3-functionalized quinolines from acetophenones and anthranil mediated by Selectfluor was achieved.  相似文献   
93.

Purpose

The objectives of this study were to develop consensus on (i) the content of a clinical assessment for adults presenting to primary care with low back and leg pain, and (ii) the most important items for diagnosing spinal nerve root involvement.

Methods

Existing literature and expert knowledge was used to compile a list of items pertaining to clinical history questions and examination tests employed in the assessment of patients with low back pain with suspected spinal nerve involvement. A Delphi consensus method was employed to rate the importance of items for clinical assessment and for diagnosis in two web-based rounds. A multidisciplinary group of 42, including GPs, physiotherapists, osteopaths, rheumatologists, spinal orthopaedic surgeons and chiropractors took part. Items were included in the final assessment when over 70% of participants rated them as important.

Results

Thirty-four items were included in the clinical assessment, and 15 items for diagnosis. History items included pain distribution in the leg, pain quality and behaviour, altered sensation, functional limitations and yellow flags, previous history of similar symptoms and outcome of previous treatment/management. Examination items included typical neurological tests including neural tension and ‘demonstration of movement that produces symptoms’.

Conclusions

We have developed a clinical assessment schedule for patients with low back pain and leg pain presenting in primary care. History and clinical items considered important for their contribution in the diagnosis of nerve root involvement were also established.  相似文献   
94.
Cytogenetic studies of 68 patients who developed secondary leukemia (SL)/dysmyelopoietic syndrome (DMS) after extensive chemotherapy and/or radiation therapy as well as patients who developed SL/DMS without such treatment showed that those patients who received radiation alone or with chemotherapy had more extensive numerical and structural abnormalities than those who received only chemotherapy. In terms of the specific chromosomal abnormalities, there are no differences between the various treatment groups. Hypodiploidy is the most common form of aneuploidy in these patients, with the most common numerical abnormality being the loss of chromosome 7. The most common structural abnormalities involved chromosomes 3 and 5. When compared with patients with de novo leukemia and DMS, the chromosomal abnormalities in these patients are more complex and extensive. Serial studies revealed that cytogenetic abnormalities do not precede the development of hematologic changes by significant time periods.  相似文献   
95.
Jansen  J; Ash  RC; Zanjani  ED; LeBien  TW; Kersey  JH 《Blood》1982,59(5):1029-1035
Monoclonal antibody BA-1 binds to B lymphocytes, to cells from most cases of non-T acute lymphoblastic leukemia (ALL), and weakly to neutrophils. To determine whether BA-1 also reacts with hematopoietic progenitor cells (HPC), we studied the effect of removal of BA-1+ cells from human bone marrow on the proliferation in vitro of the trilineage precursor cell CFU-GEMM, and on the committed progenitor cells of granulopoiesis (CFU-C) and erythropoiesis (BFU-E/CFU-E). Complement- mediated cytotoxicity using BA-1 at concentrations far beyond those required to lyse BA-1+ bone marrow cells and ALL cells did not result in inhibition of colony formation in any of the assays. A rosette separation method, using ox red blood cells coated with BA-1, resulted in enrichment of HPC in the BA-1-depleted interface, whereas very few HPC were found in the BA-1-enriched pellet. Both methods indicate that BA-1 does not bind to HPC, although binding of the antibody to the lymphohematopoietic stem cell cannot be excluded yet. The high cytotoxic capacity of the IgM antibody BA-1, and the lack of reactivity with HPC, make the antibody particularly suitable for use in autologous bone marrow transplantation for patients with ALL.  相似文献   
96.
A cell line, designated RS4;11, was established from the bone marrow of a patient in relapse with an acute leukemia that was characterized by the t(4;11) chromosomal abnormality. The cell line and the patient's fresh leukemic cells both had the t(4;11)(q21;q23) and an isochromosome for the long arm of No. 7. Morphologically, all cells were lymphoid in appearance. Ultrastructurally and cytochemically, approximately 30% of the cells possessed myeloid features. The cells were strongly positive for terminal deoxynucleotidyl transferase. They were HLA-DR positive and expressed surface antigens characteristic for B lineage cells, including those detected by anti-B4, BA-1, BA-2, and PI153/3. Immunoglobulin gene analysis revealed rearrangements of the heavy chain and kappa chain genes. The cells lacked the common acute lymphoblastic leukemia antigen and antigenic markers characteristic of T lineage cells. The cells reacted with the myeloid antibody 1G10 but not with other myeloid monoclonal antibodies. Treatment with 12-O-tetradecanoyl- phorbol-13-acetate induced a monocyte-like phenotype demonstrated by cytochemical, functional, immunologic, and electron microscopic studies. The expression of markers of both early lymphoid and early myeloid cells represents an unusual phenotype and suggests that RS4;11 represents a cell with dual lineage capabilities. To our knowledge, RS4;11 is the first cell line established from t(4;11)-associated acute leukemia.  相似文献   
97.
Stong  RC; Uckun  F; Youle  RJ; Kersey  JH; Vallera  DA 《Blood》1985,66(3):627-635
The monoclonal antibodies (MoAb) T101, G3.7, 35.1, and TA-1 were conjugated to intact ricin using a thioether linkage. These MoAb detect, respectively, the CD5[gp67], CD7[p41], CD2[p50], and [gp95, 170] determinants that are found in the vast majority of cases of T cell acute lymphocytic leukemia (T-ALL). The resulting immunotoxins (ITs) and an equimolar mixture of these ITs were evaluated as potential purgative reagents for autologous transplantation in T-ALL. Leukemic cell lines were used to compare the kinetics of protein synthesis inactivation mediated by each IT. The cells were treated with IT in the presence of lactose in order to block the native binding of ricin. The observed rates of protein synthesis inactivation correlated with target antigen expression detected by fluorescence-activated cell sorter analysis. Of the four ITs, T101-ricin (T101-R) exhibited the fastest rate of inactivation, followed in order by G3.7-ricin, TA-1-ricin, and 35.1-ricin. At concentrations greater than 300 ng/mL, a cocktail containing an equimolar amount of all four ITs (referred to as the four- IT cocktail) exhibited kinetics that were as fast or faster than those of T101-R. The long-term cytotoxic effects of individual ITs and the four-IT cocktail were evaluated using a sensitive clonogenic assay. Each IT was specifically cytotoxic and inhibited 1 to 4 logs of clonogenic leukemic cells at doses (300 to 600 ng/mL) that can be used clinically. The four-IT cocktail was highly cytotoxic; a concentration of 300 ng/mL inhibited greater than 4 logs of leukemic cells while sparing the majority of committed (CFU-GM, CFU-E) and pluripotent (CFU- GEMM) hematopoietic stem cells. The determination of both short-term kinetics of protein synthesis inactivation and longer-term inhibition of clonogenic growth allowed new insight into cell killing by IT. Our results suggest that ITs continue to act on clonogenic target cells for a period of three to five days. Interestingly, the four-IT cocktail was not as potent against clonogenic leukemic cells as T101-R alone, although it exhibited kinetics of protein synthesis inhibition that were as fast as those of T101-R alone. This finding suggests that internalized ITs may differ in the length of time they remain active within the cell. Our results also demonstrate the importance of using several different assays to evaluate IT reagents.  相似文献   
98.
Rosenoff  SH; Bull  JM; Young  RC 《Blood》1975,45(1):107-118
The proliferative state of a given tissue is a major determinant of its sensitivity to both phase-specific and cycle-specific chemotherapeutic agents. To study the extent of injury induced by antitumor agents to normal and tumorous tissues, a technique for following DNA synthesis as reflected in the incorporation of tritiated thymidine (3H-TdR) into DNA was compared to the conventional radioautographic technique of the labeling index (LI) and to the functional kinetic technique of granulocyte colony formation in vitro. Alterations in DNA synthesis induced by a single dose of cyclophosphamide in normal and tumorous tissues in vivo paralleled in many respects the changes seen when the more time-consuming techniques of the LI or granulocyte colony formation were employed. However, the recovery of granulocyte colony formation after cyclophosphamide therapy lagged behind the recovery of DNA synthesis in the bone marrow, obscuring a kinetic event of potential therapeutic significance. The determination of DNA synthesis simultaneously in normal and tumorous tissues in vivo was easy to perform and supplied therapeutically pertinent results comparatively quickly.  相似文献   
99.
The kidneys in paroxysmal nocturnal hemoglobinuria   总被引:6,自引:0,他引:6  
Long-term study of 21 PNH patients revealed an unexpectedly high incidence of functional and anatomic renal abnormalities. Most patients demonstrated varying degrees of hematuria and proteinuria distinct from hemoglobinuria. Evaluation of renal function revealed hyposthenuria, abnormal tubular function, and declining creatinine clearance. Radiologically these patients had enlarged kidneys, cortical infarcts, cortical thinning, and papillary necrosis which were confirmed by autopsy studies. Hypertension developed in eight patients. Urinary tract infection was uncommon. The renal findings bear striking similarity to those of sickle cell anemia. Contrary to the usual opinion, out studies clearly showed evidence of widespread renal pathology in PNH most likely due to repeated microvascular thrombosis similar to the venous thrombosis involving other organs in this disorder.  相似文献   
100.
To investigate bone turnover in patients with seronegative spondylarthropathy, a bone formation marker, type 1 procollagen carboxy- terminal propeptide (P1CP), and resorption markers, the pyridinium cross-links of collagen [urinary free (f) PYR and DPYR], were measured. The median f-PYR, f-DPYR and P1CP (+/-interquartile range) were 15.8 (6.00) nmol/mmol creatinine, 3.8 (2.2) nmol/mmol creatinine and 101.5 (38) micrograms/1, respectively. There was a positive correlation between resorption markers and acute-phase reactants such as C-reactive protein (r = 0.42 for PYR, r = 0.42 for DPYR, P < 0.05), and a negative correlation observed between P1CP and the erythrocyte sedimentation rate (r = -0.64, P < 0.05). In the subgroup of patients with an elevated CRP concentration, the concentration of PYR and DPYR was significantly increased (f-PYR 25.7 vs 15.8 and f-DPYR 6.6 vs 3.8, P < 0.01 for f-PYR, P < 0.05 for f-DPYR). This study suggests than an elevation in acute-phase response in patients with seronegative spondylarthropathy is associated with increased concentration of bone resorption markers with a tendency for reduction in bone formation markers. This may represent uncoupling of bone formation and resorption, leading to bone loss in such patients.   相似文献   
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