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S Sakai

Publications and source records attributed to S Sakai.

At least 577 records · Page 32Linked to original sources

[Epidemiological and therapeutic studies of gonorrheal infection--clinical efficacy of sultamicillin].

We conducted an epidemiological study including analyses of background factors of 192 male and 13 female patients with gonorrheal infection in the Sapporo area and at the same time, investigated the therapeutic efficacy of sultamicillin, an ester linked prodrug of ampicillin and beta-lactamase inhibitor sulbactam in the treatment of these patients. The percentage of infections in Sapporo was rather high in the young generation, being as high as 13.5% in teen-age boys and 30.8% in teen-age girls, which were higher than the 6.1% and 6.3% of corresponding groups in Honshu island. The source of infections was so-called special public bath-ouse which accounted for about 31.8% of all cases which however, was lower than the 50% in Honshu island. By contrast, the percentage of their friends or so-called pick-up friends as a source of infection in Sapporo was as high as 46.9% which was significantly higher than the 19.9% in Honshu. Juveniles who had nonprostitutes of the other sex as a source of infection are a characteristic of the patients in Sapporo. The isolation rate of PPNG was 13.8%. The MIC (10(6) CFU/ml) of sultamicillin ranged from 0.05 to 0.39 micrograms/ml in beta-lactamase non-producing strains and from 0.20 to 1.56 micrograms/ml in beta-lactamase producing strains showing no trend of higher MIC against beta-lactamase producing strains. There was almost no difference in the efficacy of sultamicillin between a daily dose of 750 mg (2 tablets) and 1125 mg (3 tablets) nor in side effects. The eradication rate (efficacy rate) of gonococcus following a 3-day therapy was 96.2% (38.9% excellent cure rate) in male patients and 83.3% (8.3%) in female patients. In 31% of the male patients who underwent a 7-day therapy, residual serous secretion was found though some inaccuracy is involved in this data since dropouts were not counted. This suggests the need of concurrent therapy with other appropriate drugs in consideration of possible mixed infection involving Chlamydia trachomatis or other microorganisms.

Adolescent↗

Des-O-methylolivoretin C is a new member of the teleocidin class of tumor promoters.

Des-O-methylolivoretin C, a demethylated form of olivoretin C, is a naturally occurring compound in Streptomyces mediocidicus and Streptoverticillium olivoreticuli. Des-O-methylolivoretin C is a regioisomer of teleocidin B, which has the same activity as teleocidin. The tumor-promoting activity of des-O-methylolivoretin C was studied in a two-stage carcinogenesis experiment on mouse skin in comparison with that of teleocidin. Treatments with 7,12-dimethylbenz[a]anthracene (DMBA) plus des-O-methylolivoretin C and DMBA plus teleocidin induced tumors in 63.3% and 84.6% of the mice, respectively, in week 30. The difference in the tumor-promoting activities of des-O-methylolivoretin C and teleocidin is presumably related to the regioisomeric difference in the cyclohexene ring.

9,10-Dimethyl-1,2-benzanthracene↗

[Clinical studies on doxycycline in the treatment of nongonococcal urethritis by Chlamydia trachomatis].

Twenty-one nongonococcal urethritis patients by Chlamydia trachomatis infection were treated with doxycycline (DOXY, Vibramycin) 200 mg/day orally for 2 weeks. The age of these patients were ranged from 17 to 52. C. trachomatis was eradicated 8(89%) of 9 cases on 3rd day and never reisolated on 7th day after treatment. Ten (83%) of 12 patients on 7th day and any patients on 14th day were not suffered from symptoms after treatment. Urethral discharge was not seen macroscopically, 11 (92%) of 12 patients on 7th day and any patients on 14th day. According to the criteria for urethritis requiring at least 4 WBC per high power field in urethral smear and/or first voided urine, the overall clinical efficacy rate was 44% (4/9) on 3rd day, 83% (10/12) on 7th day and 100% (9/9) on 14th day. No side effects were recognized in any cases. In conclusion, DOXY was thought to be useful and safe drug in the treatment of nongonococcal urethritis by C. trachomatis.

Adolescent↗

Analysis of synthetic sites of fourth and fifth components of serum complement system in allogeneic bone marrow chimaeras.

Synthetic tissue sites for the fourth and fifth components of complement (C4 and C5) have been investigated using allogeneic bone marrow chimaeras in mice. One group of chimaeric mice was prepared by transplanting bone marrow cells from C5-sufficient donor mice into irradiated C5-deficient recipients or vice versa, and another group was prepared by transplanting marrow cells from mice that produce high levels of C4 into irradiated recipients that are characterized by having low levels of C4 or vice versa. In such chimaeras, lymphoid cells and serum immunoglobulin allotypes were shown to be exclusively of donor origin. However, haemolytic activities of sera from the chimaeras were consistently identical with those of normal mice of the recipient strain. Similar results were obtained when the complement component levels of the sera were evaluated by double diffusion assays. C4 or C5 antigens were detected in sera of the chimaeras only when recipients were strains that are characterized by having high C4 level or were C5-sufficient mice, respectively. These findings indicate that circulating C4 or C5 complement components present in the blood are not synthesized primarily by cells that are descendants of bone marrow cells in these chimaeric mice.

Animals↗

[Comparative studies of antimicrobial agents against causative organisms isolated from urinary tract infections (1984). I. Susceptibility distribution].

Our research group was engaged for 3 years (1979-1981) in a study on sensitivities to antibiotics of 4 bacterial groups including representative pathogenic bacteria found in cases of urinary tract infections; i.e. E. coli, Klebsiella spp., Citrobacter spp., and Proteus spp. Since 1982, all the bacterial strains isolated by our group from patients with urinary tract infections and deemed by doctors in charge as pathogens were sent to the Laboratory of Clinical Pathology of Juntendo University, where they were refixed and subjected to MIC determination. This is the third year of the new study. E. coli was detected most frequently from patients with urinary tract infections and the detection frequency was 28% (323/1,153) this year (1984), whereas it was 35.3% (304/860) last year, showing a 7% decline from last year to this year. E. faecalis was next frequent organism (12.7% or 147/1,153) followed by P. aeruginosa (10.8% or 124/1,153). This order, however, was reversed from last year. Other pathogens, in a decreasing order of isolation frequencies following the above three, were as follows: Proteus spp. (9.5% or 109/1,153), S. marcescens (6.2% or 71/1,153), S. epidermidis (5.4% or 62/1,153), K. pneumoniae (4.9% or 56/1,153), Enterobacter spp. (2.4% or 28/1,153) and Citrobacter spp. (2.3% or 27/1,153). The results of the determination of the sensitivity of bacterial strains to the antibiotics are described below. Of all the oral antibacterial and antibiotic agents used against E. coli, mecillinam (MPC), cefaclor (CCL) and pipemidic acid (PPA) proved to have high antibacterial potency, and their MIC90 (the concentration to inhibit growths of 90% of the objective bacteria) was 3.13 micrograms/ml. The MIC90's of cefotiam (CTM), cefotaxime (CTX), ceftizoxime (CZX), cefmenoxime (CMX) and latamoxef (LMOX) were less than 0.39 microgram/ml. The MIC90's of cefmetazole (CMZ) and cefoperazone (CPZ) were invariably 1.56 micrograms/ml. K. pneumoniae was not sensitive to ampicillin (ABPC) and did not show much sensitivity to other oral antibacterial and antibiotic agents also. Of all the injectable preparations of antibiotics, cephem antibiotics of the third generation showed the most potent antibacterial effects against K. pneumoniae, and their MIC90's were lower than 0.10 microgram/ml for CZX, 0.20 microgram/ml for CTX, 0.39 microgram/ml for CMX, and 0.78 microgram/ml for LMOX, while MIC90's of CPZ was 6.25 micrograms/ml, which was equal to that of CMZ. The MIC90 of CTM was 0.78 microgram/ml which was identical to that of LMOX.(ABSTRACT TRUNCATED AT 400 WORDS)

Anti-Bacterial Agents↗

[Comparative studies of antimicrobial agents against causative organisms isolated from urinary tract infections (1984). III. Secular changes in susceptibility].

Cases with infections of urinary tracts were divided into 3 groups of the simple infections, and complicated infections without indwelling of catheter, and complicated infections with indwelling of catheter. Susceptibilities to antimicrobial agents of Escherichia coli, Klebsiella spp., Proteus spp., Citrobacter spp., Enterobacter spp., Pseudomonas aeruginosa and Serratia marcescens which were isolated from patients with these infections were determined. There was no tendency of decline in the susceptibilities of E. coli isolated from the patients with simple urinary tract infections (UTI). Susceptibilities of E. coli isolated from the patients with complicated UTI without and with indwelling of catheter to cephem antibiotics of the third generation were examined. The susceptibility of E. coli strains isolated from patients with complicated UTI without and with indwelling of catheter remained the same. More specifically, cefmenoxime (CMX) at a concentration of less than 0.10 microgram/ml inhibited the growth of E. coli isolated from cases without: with catheter at 74.1%: 78.3% in 1982, 75.4%: 73.3% in 1983, and 81.3%: 84.8% in 1984. Also, ceftizoxime (CZX) at a concentration of less than 0.10 microgram/ml inhibited the growth at 83.3%: 95.7% in 1982, 89.2%: 86.7% in 1983, and 91.7%: 97.0% in 1984. Latamoxef (LMOX) at less than 0.10 microgram/ml inhibited the growth at 59.3%: 43.5% in 1982, 47.7%: 40.0% in 1983, and 47.9%: 42.4% in 1984. The antibacterial effect of penicillin against Klebsiella spp. was found to be poor, while those of oral cephem antibiotics, cephalexin (CEX), cefaclor (CCL), and cefazolin (CEZ) which is the cephem antibiotics of the so-called first generation and cefotiam (CTM) among other cephem antibiotics of the so-called second generation were relatively good. A study of susceptibilities of Klebsiella spp. isolated from patients with complicated UTI without and with indwelling of catheter revealed inhibition of growth by CTM at a concentration of 0.39 microgram/ml at 84.0%: 75.9% in 1982, 70.6%: 75.0% in 1983, and 95.8%: 77.8% in 1984. Cefmetazole (CMZ) at a concentration of 0.39 microgram/ml showed a relatively lower rate of growth inhibition of Klebsiella spp., while at 0.78 microgram/ml it inhibited the growth at 88.0%: 72.4% in 1982, 52.9%: 50.0% in 1983, and 70.8%: 66.7% in 1984. The antibacterial effects of both CTM and CMZ against Klebsiella spp. isolated from patients with indwelling of catheter were found to be poor, and some of the bacterial strains showed a MIC over than 100 micrograms/ml.(ABSTRACT TRUNCATED AT 400 WORDS)

Anti-Bacterial Agents↗

[Epidemiological and therapeutic studies on gonorrheal infections--clinical efficacy of T-2588. (Sapporo Clinical Research Group for STD)].

T-2588, a new oral cephalosporin antibiotic, for gonorrheal infections, was administered to 146 patients with gonorrheal infection cases (140 urethritis cases in males, 6 cervicitis cases in females). Twenty three strains (20.9%) out of 110 clinically isolated gonococci were PPNG. The MICs of T-2588 for the clinically isolated gonococci strains showed a distribution peak at 0.025 microgram/ml and ranged between 0.0125 microgram/ml to 0.1 microgram/ml when an inoculum size of 10(6)/CFU/ml was used. The distribution of MICs of PPNG also showed a peak at 0.025 microgram/ml and the maximum MIC was 0.2 microgram/ml, which is one dilution tube higher than the maximum MIC of non-PPNG. The rate of complication by Chlamydia trachomatis was 20.9% in male and 33.3% in female. At the dose of 400 mg given 2 times a day, the efficacy rate for the males on the 3rd and 7th day was 90.5% (efficacy rate against PPNG, 73.3%) and 95.3% (80.0%), respectively. At the dose of 300 mg given 3 times a day, it was 93.3% and 100%, respectively, and at the dose of 600 mg given 3 times a day, it was 100% and 100%, respectively. Therefore, the administration of T-2588 3 times a day resulted in a higher efficacy rate than that given 2 times a day. This effect was extremely marked in the case of patients with PPNG. The best clinical results were obtained at a daily dose of 600 mg t.i.d. Although the female patients were few, in number and no conclusion can be drawn, the best results were obtained with a daily dose of 600 mg t.i.d. (100%). There were three mild side effects (1.7%), which could not be attributed to the administration of T-2588 in the present study. In conclusion, T-2588 can be to be expected sufficiently clinically effective against gonorrheal infections, including PPNG, at a daily dose of 600 mg t.i.d. for 3 days.

Adolescent↗

[Epidemiologic and therapeutic studies on gonorrheal infections--use of AT-2266--Sapporo Clinical Research Group for STD].

From August of 1982 through February of 1983, the Sapporo Clinical Research Group for STD treated 131 cases of male gonorrheal urethritis at its affiliated clinical facilities in Sapporo City. The therapeutic efficacy of AT-2266 was investigated, together with an epidemiological study on the cases and bacteriological studies on the isolated strains of gonococcus. In addition, a few cases of female gonorrheal cervicitis were treated, and the therapeutic results for 3 of these cases evaluated. AT-2266 was administered at a daily dosage of 600 mg in one dose to 14 patients, 2 doses to 10 patients and 3 doses to 98 patients. At the end of 3 days of this therapy, the gonococci had been eliminated in all of the cases, but there was variation in the status of disappearance of the secretion. The "excellent" efficacy rates for these three regimens were thus 7.7%, 50% and 57%, respectively. These results showed that administration of the total dosage in two or more divided doses maintained higher minimum concentrations of the antibiotic in the blood and the urine, and were thus more clinically beneficial than when the dosage was given as one daily dose. Of the patients who were treated with 600 mg/day of AT-2266 in 3 divided doses, 93 were evaluated for the therapeutic efficacy. At the end of 3 days 57.0% were "excellent" cases, 39.8% were "good" cases and 3.2% were "fair" cases, and at the end of 7 days of therapy, 67 patients were 74.6% "excellent" cases, 23.9% were "good" cases and 1.5% were "fair" cases. The clinical efficacy rate was thus quite high. Those cases in which the secretion and leukocytes had not disappeared from the urine even at the end of the 7 days of therapy were probably cases of mixed infection involving Chlamydia, etc. Eight of the 77 gonococcal isolates (10.4%) were beta-lactamase producers. The MIC of AT-2266 hardly differed with the size of the bacterial inoculum. With an inoculum of 10(6)CFU/ml, the MIC distribution showed two peaks, i.e., at 0.05-0.2 micrograms/ml and 3.16-12.5 micrograms/ml. Only 11.7% of the strains were found to have high MICs. The distribution of these high MICs was found to be unrelated to the ability to produce beta-lactamase. Mild side effects of AT-2266 were seen in 2 out of 128 patients. (1.6%), an extremely low incidence.

Adolescent↗

[Therapeutic studies on male non-gonorrheal urethritis--use of AT-2266--Sapporo Clinical Research Group for STD].

AT-2266 tablets were administered orally in a daily dosage of 600 mg for 7 consecutive days as treatment of non-gonorrheal urethritis in 106 cases. The therapeutic results in 90 cases were investigated, and a detailed analysis of various background factors was also performed. Most of the patients were between 15 and 35 years old; 11.3% of the patients were between 15 and 19 years old. The source of infection was a "professional" woman such as a prostitute in 37 cases, and a non-professional woman in 53 cases. This is noteworthy because the source is more often a "professional" women in the case of gonorrhea. Bacterial isolates were obtained by culture of the urethral secretions. Most were gram-positive cocci, especially S. epidermidis, but, in 51.7% of the patients, no bacteria could be cultured. The urethral secretion was purulent in 51.9% of the patients, and serous in the remaining 48.1%. The efficacy rates obtained when AT-2266 was administered in a daily dosage of 600 mg (in 3 divided oral doses) for 7 days were as follows. In the purulent secretion group, the 3-day and 7-day therapeutic efficacy (elimination of the secretion) rates were 24.2% and 61.2%. In the serous secretion group, the corresponding efficacy rates were 36% and 71.4%. Thus the therapeutic efficacy was slightly inferior in the purulent secretion group. Oral administration of AT-2266 resulted in side effects in 5 of the patients (5.5%). These side effects consisted primarily of mild gastrointestinal disturbances, which did not require discontinued drug administration.

Adolescent↗

[Therapeutic studies on chronic prostatitis--use of AT-2266--Sapporo Clinical Research Group for STD].

AT-2266 is a new antibiotic of the pyridone carboxylic acid class which possesses a broad, low-MIC antibacterial spectrum. Therapeutic studies were carried out on the use of this drug in the treatment of chronic prostatitis, and at the same time a pathological analysis was performed on chronic prostatitis. The subjects were 97 chronic prostatitis patients for whom the prostate fluid had been confirmed to contain at least 30 leukocytes per 400-power magnification field. An analysis of the background factors revealed that 71% of these patients had a past history of gonorrheal or non-gonorrheal urethritis. Culture of the prostate fluid yielded gram-positive cocci (S. epidermidis in most cases) in 44.1% of the patients. E. coli was detected in 3.2% of the patients, while the remaining cases gave negative cultures. In 53.9% of the patients who had not been receiving therapy prior to inclusion in this study, the subjective symptoms consisted of urethral irritation or irritation upon urination. In the other patients, the relationship of the complaints to the disease could not be clearly established. In the patients who had been receiving therapy, the majority did not complain of subjective symptoms. AT-2266 was administered in a daily dosage of 600 mg (in 3 divided doses) for 14 days. The therapeutic efficacy was evaluated. At the end of 7 days of AT-2266 therapy, 15.5% of the previously-untreated group and 8% of the previously-treated group were "excellent" cases, and the efficacy rate was 32.8% and 36%, respectively, when the "good" cases were also included. At the end of the full 14 days of therapy, the corresponding efficacy rates were 21.7% and 17.4%, and 54.3% and 56.5%. Considerable improvement was achieved in the subjective symptoms of urethral irritation and irritation upon urination at the end of 7 days of therapy, and the improvement was even greater following the next 7 days of treatment. With regard to the complaints for which the relationship to the disease could not be clearly established, however, the improvement was not very good: there was not much difference between the results on the 7th and 14th days, and the elimination rate even after 14 days was slightly below 30%. In the previously-untreated patients, improvement in leukocyte count in the prostate fluid to 10 or fewer cells per microscopic field was achieved in 15.6% at 7 days and 21.7% at 14 days. As side effects of AT-2266, mild symptoms were observed to occur in only 1.8% of the patients.

Adult↗

[Well-controlled comparative study on aztreonam and cefoperazone in the treatment of complicated urinary tract infections].

A well-controlled comparative study was conducted in order to evaluate the efficacy, safety and usefulness of the monobactam antibiotic aztreonam (AZT) in complicated urinary tract infections (UTI) using cefoperazone (CPZ) as the control drug. Patients with complicated UTI due to Gram-negative bacteria were examined. However, in polymicrobial infections, the cases caused by Gram-negative and Gram-positive bacteria were also examined. Both drugs were administered 1 g, twice a day by intravenous drip infusion for 5 days. Overall clinical efficacy was evaluated by the criteria proposed by the UTI committee in Japan. Of the total 394 cases, the clinical efficacy was evaluated for 152 cases in the AZT group and 143 cases in the CPZ group excluding 99 cases of exclusion or dropout. There was no statistically significant difference in the back ground characteristics between the 2 groups. The overall clinical efficacy rate was 55.3% for AZT and 55.2% for CPZ with difference not significant. As for clinical efficacy, in the monomicrobial infection after postprostatectomy (G-2), AZT was superior to CPZ (P less than 0.05), whereas in the polymicrobial infection without indwelling catheter (G-6), CPZ was superior to AZT (P less than 0.1). The overall bacteriological eradication rate was 77.2% for AZT and 74.5% for CPZ. For Gram-negative bacteria only the eradication rate for AZT (83.2%) was superior to that for CPZ (74.6%). This was probably due to the stability of AZT to beta-lactamase. Side effects were observed in 3 cases out of 201 in the AZT group and 5 cases out of 189 in the CPZ group. No severe abnormal laboratory finding was observed in any group; there was no significant difference between the 2 groups. Consequently, AZT was judged to be an antibiotic with clinical usefulness equal to, or even superior to that of CPZ.

Adolescent↗

[Comparative studies of antimicrobial agents against causative organisms isolated from urinary tract infections (1984). II. Background of patients].

Groups of bacteria were isolated from patients with infections of urinary tracts, and backgrounds of these isolates and patients have been studied in terms of the sexual distribution, and distributions of sexes versus age of the patients relationships between bacterial types and sexual and age distribution of the patients from whom the isolates were obtained correlation ages of patients and types of infections, the association of certain types of bacteria with certain infections and the effect of antibacterial treatments on these types of bacteria, approximately 20% of simple infections of urinary tracts occurred in males and approximately 80% in females on average from 1981 to 1984. This ratio showed hardly any changes during this period. Likewise, male patients comprised approximately 60-70% of all the cases with complicated infections of urinary tracts regardless of indwelling or without indwelling of catheters. In terms of age, the ratio of urinary tract infections was almost universally observed, e.g., for patients in 40's: 10.0% in 1981, 11.0% in 1984, while in those in 70's: 25.5% and 21.2%, respectively. Consequently, background factors of the cases with infections of urinary tracts, such as sexes, age, or simple or complicated, remained almost stable, whereas bacteria involved showed considerable variations. In 1982 and 1983, the frequency of isolations of Enterococcus spp. was approximately 8% in both males and females. However, in 1984, the frequency of isolation of Enterococcus spp. was 22.5% in the males 17.9% in the females. The frequency of isolation of Enterococcus spp. increased in all age groups, but the frequency was not particularly high among the aged. A study on variations and isolation frequencies of bacteria before the administration of antibiotic agents revealed that isolation frequencies of Enterococcus spp. sharply increased in 1983, and this high frequency remained in 1984. The frequency of isolation of E. coli tended to decrease year after year. This finding represents that the frequency of isolations of E. coli from materials of cases with simple infections of urinary tracts has decreased, showing that pathogenic bacteria from simple infections of urinary tracts were becoming similar to that of the complicated infections of urinary tracts. These findings seem to be worth mentioning here. In cases receiving administrations of antibacterial and antibiotic agents for more than 8 days. Frequencies of isolation from cases without catheter retention and from those with catheter retention were similar.(ABSTRACT TRUNCATED AT 400 WORDS)

Adult↗

[A case of leiomyosarcoma of the prostate].

A 50-year-old man with the symptom of anal pain was treated by pelvic exenteration, ileal conduit diversion and artificial anus. The pathologic diagnosis was leiomyosarcoma of the prostate. At 5 months post-operatively, the patient had no evidence of metastasis or recurrence.

Humans↗

[Clinical studies on doxycycline treatment of urogenital Chlamydia trachomatis infections].

Nineteen patients of male NGU and 8 patients of female NGC were treated with doxycycline (DOXY, 200 mg/day for 14 days). C. trachomatis positive rate of male NGU was 12/19 (63%), and that of female NGC was 4/8 (50%). C. trachomatis positive rate of male NGU after treatment of DOXY for 3 days, 7 days and 14 days, was 83%, 17% and 0%, respectively. Serous discharge after treatment of DOXY for 3 days, 7 days, 14 days, was continued in 100%, 33%, 0%. Administration of DOXY (200 mg/day for 14 days) was considered good treatment for male C. trachomatis positive NGU.

Chlamydia Infections↗

[Detection of urinary polyamine by a new enzymatic differential assay. (I). Fundamental study on a new enzymatic differential assay].

A new enzymatic method for determining urinary polyamine concentration by fractionation of the urinary acetyl conjugate into free polyamines with acylpolyamine amido-hydrolase and quantification using two kinds of amine-oxidase of different substrate specificity was examined. High recovery rates of urinary polyamine by enzymatic hydrolyzation were obtained, namely, 95 +/- 4% for diamine, 95 +/- 1% for spermidine and 99 +/- 2% for spermine. Furthermore, excellent linearity was demonstrated with up to 150 mumole/l diamine, up to 75 mumole/l spermidine and up to 50 mumole/l spermine. Although urinary polyamine concentration varied diurnally even after correction of urinary creatinine, day-to-day variation disappeared. In 24-hour pooled urine and voluntary urine, diamine, spermidine and spermine correlated relatively well. Urinary leukocytes and erythrocytes exerted no influence on urinary polyamine.

Diamines↗

[Detection of urinary polyamine by a new enzymatic differential assay. (II). Comparison with conventional method].

A new method of determining urinary polyamine concentration was compared with other techniques, namely, high pressure liquid chromatography (HPLC) and a polyamine test-enzyme kit. The values obtained by the new method, HPLC, and polyamine test-enzyme kit correlated well for all the fractions: diamine, spermidine and spermine. The correlation between the new method and the polyamine test-enzyme kit gave r = 0.9702, y = 1.1359x + 5.1266 (n = 48).

Chromatography, High Pressure Liquid↗