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The network model developed in a previous paper is applied to the simple shear flow of polymer melts. The constitutive equation obtained consists of two terms. One of them describes the stress due to the network strands which exist at the onset of the deformation, dissociate during the deformation and result in a single integral constitutive equation with a strain dependent damping function. The formulation of the damping function in invariant form seems to be almost impossible. The second normal stress differenceN 2 of the model is not zero,but has negative values. According to our model this is a consequence of the deformation dependence of the disentanglement process. The theory is compared with experimental data for a LDPE melt. It is found that the model explains the main features of the shear flow behaviour of the LDPE melt investigated preciously.

Early stages of Si(111) oxidation via photochemical decomposition of N2O has been further studied with X-ray photoelectron spectroscopy (XPS). In order to reveal the chemical nature of the oxygen atoms bonded to the top-most silicon atoms, a hydrogenated silicon radical, SiHx, which was formed via photochemical decomposition of Si2H6, was deposited on the suboxide surfaces. From the analysis of the asymmetric decrease of the O(1s) spectra, we found that the oxygen atoms in the on-top sites made a SiO bond preferentially with the deposited SiHx radical within a monolayer coverage, playing a role in mediating the substrate oxide and the deposited a-Si:H to form the SiOSi species. The corresponding Si(2p) spectra showed a peak shift towards the higher binding energy side of 1 eV with respect to the Si(2p) peak of the bulk a-Si: H film. This chemical shift also indicates the existence of the interfacing SiOSi species. The interfacing SiOSi species were unstable with respect to heating to 500–600° C.

130例の大腸癌症例につき術前検査としてCTを施行し, 肝転移, 漿膜浸潤, リンパ節転移, 腹膜播種性転移について手術診断との対比を行った.CTは横断断層面が得られるという利点から奨膜浸潤に関し手術所見と高い相関を示し, 特にS3症例については他の画像診断に比べて明らかに高い診断能を有するものと考えられた.リンパ節転移に関してもCTは手術所見とかなり高い一致を示すが, 必ずしも組織診断と一致しないことが問題となった.腹膜播種性転移に対してはsensitivityの低さが問題となる.また直腸癌における縦方向の浸潤範囲の評価には直接冠状断スキャンが有用があった.CTは肝転移のみならず局所病変の評価に関しても高い診断能を有し, 大腸癌の術前検査として重要な位置を占め得るものと考えられた.

The daily fluctuation of the concentration of fallout particles in the ground-level air whose diameters ranged from 1 to 30 μ was observed for a period of about 3 months following the fifth Chinese nuclear explosion of December 28, 1966. It appeared that fallout particles larger than about 10 μ in diameter fell on the ground mainly by gravitational settling shortly after the explosion, and some smaller particles circulated with the air motion around the globe more than once. It was also found that about 20 days after the explosion the fluctuation of the particle concentration was rather well related to the variation of meteorological situations; the particle concentration decreased during periods of precipitation and increased during periods of high atmospheric pressure.

The anatomical structures of the anus and anal canal are complicated, and various malignant tumors. develop. in the area, where the juncture of postallantoic gut and the proctoderm occurs during embryonal developement.The incidence is not so high in Japan, however, there are many intersting cases reported especially in respects of their histopathology.The three interesting cases were reported with a review of literatures-that is, the adenocarcinoma which seemed to have originated from the anal gland, the anal squamous cell carcinoma which responded to Blemycin treatment and the reticulum cell sarcoma which developed at the anorectal junction.

An undifferentiated carcinoma of the pancreas in a 50-year-old man was found to be associated with a very elevated level of serum hCG. Syncytiotrophoblastic tumor cells were seen sporadically in the cancer nest, and they showed diffuse positive staining for hCG by immunohistochemical techniques. Positive staining for hCG was also observed in a few mononucleated cancer cells. The results indicated ectopic production of hCG by pancreatic cancer with a choriocarcinomatous feature and tended to support the hypothesis of the retrodifferentiation theory holding that choriocarcinoma is derived from a pre-existing pancreas cancer through metaplastic proliferation.

The second exon of the HLA-DQA1 genes was selectively amplified from genomic DNAs of 72 HLA-homozygous B cell lines by the polymerase chain reaction (PCR). Amplified DNAs were digested with HaeIII, Ddel, ScrFI, FokI and RsaI, which recognize allelic sequence variations in the polymorphic segments of the DQA1 second exon, and then subjected to electrophoresis in polyacrylamide gels. Eight different polymorphic patterns of restriction fragments were obtained, and seven were identical to patterns predicted from the known DNA sequences, correlating with each HLA-DQw type defined by serological typing. The remaining one pattern cannot be explained from the sequence data, suggesting the presence of a novel DQA1 allele at the nucleotide level. This PCR-RFLP method provides a simple and rapid technique for accurate definition of the HLA-DQ types at the nucleotide level, eliminating the need for radioisotope as well as allele specific oligonucleotide probes and can be extended and applied to HLA-DR, -Dw DP typing.

The regulatory mechanism of hepatic sulfation of N-hydroxyarylamine and N-hydroxyarylamide by endocrine factors has been studied in rats. The cytosolic sulfations of N-hydroxy-2-acetylaminofluorene (N-hydroxy-AAF) and 2-hydroxyamino-6-methyldipyrido[1,2-a:3',2'-d]imidazole (N-hydroxy-Glu-P-1), which were determined by the reductive formations of 2-acetylaminofluorene and Glu-P-1, were seven to nine times and three times higher, respectively, in male than female rats. Hypophysectomy of male rats decreased their activities to 23% and 41% of the levels of the untreated animals, respectively. Intermittent treatment of hypophysectomized male and female rats with human growth hormone (hGH) significantly increased their sulfating activities of both compounds. Infusion of hGH also enhanced the sulfating activity of N-hydroxy-AAF but not of N-hydroxy-Glu-P-1. The sulfating activity of N-hydroxy-AAF was also decreased by castration at neonate and was increased by the administration of testosterone propionate to gonadectomized male and female rats. Testosterone propionate and estradiol benzoate had no effect on hypophysectomized rats, but estradiol benzoate repressed the sulfating activities of N-hydroxy-AAF and N-hydroxy-Glu-P-1 in hGH-treated hypophysectomized male rats. These results indicate that sex steroids elicit their effects on the sulfations of N-hydroxyl-aryl compounds through modulating the action of growth hormone at hypothalamus-pituitary and hepatic levels in rat livers.

The effects of growth hormone and ectopic transplantation of pituitary gland on the amounts of sex-specific cytochrome P-450, P-450-male and P-450-female, and the activities of testosterone and drug hydroxylases in male rat liver microsomes were studied. Hypophysectomy decreased the content of P-450-male, without changing the total cytochrome P-450 level. The continuous infusion of growth hormone into hypophysectomized rats and the transplantation of pituitary gland under the renal capsule caused a further decrease in P-450-male content and an expression of P-450-female. In contrast, the intermittent injection of growth hormone into hypophysectomized rats increased P-450-male content to the level seen in intact male rats. The activities of testosterone 2 alpha- and 16 alpha-, but not 6 beta-, 7 alpha-, or 15 alpha-hydroxylase, were changed in association with the level of P-450-male by these treatments. Anti-P-450-male immunoglobulin G inhibited testosterone 2 alpha- and 16 alpha-hydroxylations, but not 6 beta-, 7 alpha- or 15 alpha-hydroxylation. These results indicate that growth hormone regulates the expression of P-450-male responsible for testosterone 2 alpha- and 16 alpha-hydroxylations. The metabolism of 7-propoxycoumarin, benzo(a)pyrene and aminopyrine also changed with the content of P-450-male, although the correlation was less than that observed with testosterone 2 alpha- and 16 alpha-hydroxylation.

Treatment of enuresis was studied in 168 patients. The patients were divided into two groups, the drug therapy group which consisted of 88 patients who were treated with drugs only, and the bladder training therapy group which consisted of 80 patients who were treated mainly with bladder training supplemented with drug therapy. In the drug therapy group imipramine was the first choice and was used at bed time. The dose of imipramine was initially 1 mg/kg and was gradually decreased if it worked well, and changed to other drugs if it did not work well. In the bladder training therapy group, bladder training was performed in all patients for 3 months, and 22 patients who cured further bladder training was continued, whereas the rest of the patients (58 patients) drug therapy was started in addition to bladder training. After 3 months, drug therapy was effective for 54 patients (61%) including 10 patients (11%) who were cured, and bladder training therapy plus drug therapy was effective for 55 patients (69%) including 22 patients (28%) who were cured. The number of cured patients in the bladder training therapy group was significantly larger than that of the drug therapy group (p less than 0.01). After 6 months, drug therapy was effective for 56 patients (64%) including 16 patients (18%) who were cured, and bladder training therapy plus drug therapy was effective for 66 patients (83%) including 30 patients (38%) who were cured. The number of effective and cured patients in the bladder training therapy group was significantly larger than that in the drug therapy group (p less than 0.01).(ABSTRACT TRUNCATED AT 250 WORDS)

The medullary collecting tubules (MCT) and the medullary thick ascending limb of Henle's loop (MAL) are two major sites of [8-Arg]-vasopressin (AVP) action, via cyclic AMP, on the mammalian nephron. In the present study, the effect of forskolin and forskolin in combination with AVP on accumulation of cyclic AMP in tubular segments of MAL and MCT microdissected from rat kidney was examined in vitro. Under all tested conditions, forskolin stimulated the accumulation of cyclic AMP to a greater degree in MCT than in MAL. In MAL, the effects of forskolin and AVP were synergistic; the increase in cyclic AMP after incubation with forskolin and AVP added together was 150% greater than the arithmetic sum of the increases elicited either by AVP or by forskolin alone. On the other hand, in MCT the stimulatory effects of AVP and forskolin were strictly additive. These results suggest that an intramembranous arrangement of AVP-sensitive adenylate cyclase complex differs in two types of epithelial cells located in the same tissue. The potentiating effect of forskolin on AVP-stimulated cAMP generation in MAL can be helpful in experimental studies of AVP-sensitive cyclic AMP metabolism in this nephron segment, which has a variable sensitivity to AVP in the kidneys of diverse mammalian species.

In 68 patients with chronic renal failure (CRF), 15 patients with duodenal ulcer and 15 normal subjects, basal plasma gastrin levels and basal and stimulated gastric acid secretion were measured. Two antisera were used: antiserum R2702 with specificity for human G34 and its N-terminal fragments [G34] and antiserum 2604 with specificity for the four main components of gastrin (total gastrin). Basal gastrin concentrations of both total gastrin and G34-like immunoreactivity (G34LI) were significantly higher in the CRF patients than in the other two groups, irrespective of dialysis. Total gastrin levels were not correlated with serum creatinine levels. Total gastrin levels were significantly decreased during hemodialysis, but G34LI levels showed no significant change. A small amount of total gastrin was detected in the dialysate by antiserum 2604. As to the postprandial gastrin release, in the first 30 min, the pattern of response in the patients with CRF was similar to that of the normal subjects, but the peak value was attained later, and the response was more rather prolonged. Gastric analysis showed a low basal acid out put and impaired acid secretion in response to secretagogue. It is concluded that (1) one of the predominant circulating forms of gastrin in CRF is G34LI, and (2) the hypergastrinemia in the CRF patients is probably due to reduced removal of gastrin by kidneys, increased gastrin production by impairment of the negative acid feedback mechanism induced by parietal cell dysfunction or reduced parietal cell sensitivity to gastrin by atrophic gastritis.

Blood levels of clindamycin-2-phosphate in dog at dosis of 10 mg/kg body weight showed the maximum of 21 mug/ml 30 seconds after one-shot i.v. administration. Continuous infusion of the antibiotic at the infusion speed of 150 and 300 ml/hour/10 kg b.w. with 6 mg/ml solution maintained blood levels of 30 and 170 mug/ml respectively. It may be recommended clinically to use lower concentration than 6 mg/ml to avoid cardiocirculatory disturbances. Four cases of surgical mixed infections with gram-positive cocci, gram-negative bacilli and anaerobes were treated with clindamycin-2-phosphate at a daily dosis of 1,200 mg intravenously and 2 of 4 cases revealed good clinical response. There was none of the haematological, hepatic, nephrontic, cardiocirculatory and allergic side effects.

The relationship between growth hormone and testosterone (T) 6 beta-hydroxylase was investigated in normal and hypophysectomized (hypox) male rats. The administration of human growth hormone (hGH) by either intermittent injections or continuous infusion to normal and hypox rats decreased the activity of T 6 beta-hydroxylase in hepatic microsomes. Hypophysectomy did not reduce, but rather increased the 6 beta-hydroxylase activity, while the 16 alpha-hydroxylase activity decreased. These results, together with the data from a Western blot, indicate that growth hormone acts as a repressive factor for the expression of T 6 beta-hydroxylase in a manner different from the regulation of T 16 alpha-hydroxylase.

The relationship between 5 positive components of somatosensory evoked potentials (EPs) and subjective response to electrical stimuli, which were recorded in the same human subjects, was assessed in the present study. Five levels of tactile stimuli and 6 levels of noxious stimuli were applied to the tip of the right index finger. The relationship between the magnitude of subjective response and stimulus intensity was well expressed by a power function. Of 5 major positive components in an EP, P30 and P50 were localized at contralateral primary somatic projection area, while P90, P190 and P270 were at the vertex area. The amplitude of the 5 components systematically increased as increasing stimulus intensity, and also increased with the magnitude of subjective response. A significant correlation between the amplitude of P30 or P50 and stimulus intensity was found when the effect of subjective response was partially out. By contrast, the amplitudes of P190 and P270 were associated with subjective response when the effect of stimulus intensity was partially out. These results suggest that the earlier EP components reflect sensory signal processing, while the latter ones concern the subjective evaluating system.

The aminopeptidase P gene in Escherichia coli HB101 was cloned into the plasmid pBR322. Introduction of the hybrid plasmid, pAPP01, into the E. coli DH1 resulted in an 8-fold increase of aminopeptidase P activity as compared with that of the host. The enzyme was purified by series of chromatographies on DEAE-Sephadex, QAE-Sephadex, and hydroxyapatite. The purified enzyme was homogeneous as judged by disc-gel and SDS-gel electrophoreses. the enzyme was inhibited strongly by EDTA and slightly by p-chloromercuribenzoate, but was not affected by diisopropyl phosphorofluoridate, E-64, or iodoacetic acid. The optimum pH of the enzyme was 8.5. The enzyme was stable at pH 8 to 9. After incubation for 30 min at pH 8.0, 50% remaining activity was observed at 50 degrees C. The enzyme was activated 3-fold by the addition of 5 microM Mn2+. The molecular weight of the enzyme was estimated to be 50,000 and 200,000 by SDS-PAGE and gel filtration, respectively. The amino terminal amino acid was identified to be serine by Edman degradation, indicating that the enzyme is composed of a homo-tetramer. The enzyme hydrolyzed X-Pro bonds (X = amino acid) of peptides. These characteristics suggest that cloned aminopeptidase P is identical to APP-II reported by Yoshimoto et al. (Agric. Biol. Chem. 52(8), in press (1988].

Lateral and medial branch of the frog's IXth nerve innervates rostral third and caudal two-thirds of the tongue surface, respectively. The amounts of gustatory signals in these branches differ in proportion to the area they supply.

Investigations were carried out to determine the effects of omeprazole on mucus glycoprotein in rat gastric mucosa. Quantitative and qualitative changes in mucus glycoprotein, isolated from omeprazole-treated rats with or without acetylsalicylic acid-induced gastric damage, and the degree of gastric mucosal injury were studied. Omeprazole, in a dose-dependent manner, prevented macroscopical mucosal damage induced by acidified acetylsalicylic acid. A considerable decrease in corpus mucus glycoprotein (54%) and antral mucus glycoprotein (72%) was observed in acetylsalicylic acid-treated rats and acetylsalicylic acid reduced the amounts of fucose and galactose of corpus mucus glycoprotein. Pretreatment with omeprazole partially restored a quantitative reduction and a qualitative change of carbohydrate portion in corpus mucus glycoprotein induced by acetylsalicylic acid. A single administration of a high dose of omeprazole (200 mumol/kg) also induced the reduction of corpus mucus glycoprotein content (82%), although no changes in the carbohydrate component were observed. The decrease in corpus mucus glycoproteins induced by omeprazole might be due to a cause different from that of acetylsalicylic acid-induced mucus glycoprotein reduction.

The relationship between 10 components of somatosensory evoked potentials (EPs) and pain discrimination in man was studied using Signal Detection Theory (SDT) psychophysics. Two painful electrical stimuli were delivered to the right index finger in random order over all trials. EPs were recorded from the scalp at the contralateral primary somatic projection area while subjects performed SDT discrimination. The stimulus-response combination was classified into 4 categories according to SDT response: hits, misses, false alarms (FAs) and correct rejections (CRs). The amplitudes and peak latencies of EPs in 4 categories were compared with each other. EPs associated with hits and FAs had significantly greater amplitude at P 190, N 220 and P 270 than those associated with misses and CRs, while there was no change in the amplitude of other components. The amplitude of these 3 components systematically increased with an increase in the magnitude of subjective response. Peak latencies of all components were not related to the response categories. These results indicate that the amplitude of the 3 last components may be concerned with the pain evaluating system in the brain.

Aus partiell relaxierten Puls Fourier Transform 13C-Kernresonanzspektren von cis-l,4-Polybutadien sowie aquimolaren cis-trans-1,4- und cis-1,4–1,2-Polybutadienen regellosen Sequenzaufbaus wurden die Spin Gitter Relaxationszeiten einzelner C-Kerne unterschiedlicher chemischer Verschiebung bestimmt. Bei cis-1,4-PB wurden zusatzlich aus Linienbreiten T2-Werte ermittelt und Kernoverhauserfaktoren gemessen.

The effect of preoperative intra-arterial infusion of mitomycin C, 5-fluorouracil (5-FU) and adriamycin (ADM) were studied in seven patients with locally advanced breast cancer, including five inflammatory carcinomas, and a patient with stromal sarcoma of the breast. Reducing rate of the primary tumor of more than 30% was observed in all cases, and remarkable degenerative changes of tumor cells were histologically noted in six out of eight surgical specimens. The tissue concentrations of 5-FU and ADM were also studied in five breast cancer patients. There was no correlation between the concentration of 5-FU or ADM and histological effect. In intra-arterial infusion, ADM seemed to have a high affinity to the regional lymphnode and breast tumor, compared to normal breast tissue and might also be applicable to the control of lymphnode metastasis. Three out of six cases which received radical mastectomy subsequently had recurrence except in the regional lymphnodes and the prognosis was unsatisfactory (5 year survival was 2/4). Other alternative or multi-disciplinary treatment seems to be necessary for improving the survival rate.

The mechanism of the suppression of an ethanol-inducible cytochrome P-450 (P-450DM/j) by pituitary hormone has been studied in rats. The hepatic content of P-450DM/j protein quantitated by Western blots was low but was 2-fold higher in male than female untreated rats (75 and 34 pmol/mg of protein, respectively). The content was increased 2.6-fold (male) and 5.6-fold (female) by hypophysectomy and the sex-related difference was abolished. Treatment of hypophysectomized rats with human growth hormone (hGH), but not with prolactin, reversed the increased amounts of P-450DM/j protein. The hGH-induced suppression was more effective with the continuous infusion than intermittent injection. The hepatic level of P-450DM/j mRNA, determined by the use of a 23-mer oligonucleotide probe, was also changed by hypophysectomy and/or hGH-treatment, largely in parallel with the changes in the content of P-450DM/j protein and microsomal p-nitrophenol and aniline hydroxylations. These results suggest that growth hormone exerts the suppressive effect on P-450DM/j through a somatogenic receptor-mediated process. In another growth hormone-depleted condition, diabetes, the hepatic level of P-450DM/j mRNA was also increased to a level similar to that in hypophysectomized rats, but the protein content was 2- to 3-fold higher in diabetic than hypophysectomized rats. These results indicate, in addition to the reduction of serum growth hormone level, the presence of another stimulatory factor, which acts translationally or posttranslationally in livers of diabetic rats. On the other hand, coordinate changes in the level of P-450DM/j protein and the mRNA in hypophysectomized rats indicate that growth hormone acts rather directly and suppresses the level of P-450DM/j mainly at a pretranslational step in rat livers.

Early components of the somatosensory potential (SEP) evoked by tactile stimulation of the tongue were recorded from the scalp in 7 normal subjects and compared with those resulting from taps on the middle finger. 1.(1) Unipolar but not bipolar recording of SEP to tapping the tongue failed to differentiate the early components from large EEG deflections of myogenic origin. No such contamination was seen in either unipolar or bipolar recording of SEP following taps on the finger. 2.(2) The early components evoked by tappingv the tongue consisted of 4 main deflections; the first negative wave (N 1 ) peaking at about 13 msec after the stimulus was followed by the first positive (P 1 ), second negative (N 2 ) and second positive (P 2 ) at about 23, 32 and 44 msec, respectively. Each wave had a shorter latency by several msec than the corresponding wave elicited by taps on the finger. 3.(3) To demonstrate the spatial distribution of a SEP wave over the scalp, a method of amplitude transformation of bipolar records was developed. Topography of the transformed amplitudes of P 1 wave, thus obtained while tapping the tongue differed from that obtained while tapping the finger; the former indicated bilateral distribution of the P 1 with the maximal amplitude at contralateral (T 3 or T 5 ) and ipsilateral (T 4 or T 6 ) temporal loci, whereas, in the latter, the distribution was most prominent over the contralateral posterior quadrant with the maximum at parietal locus (C 3 ). P 1 wave in SEP thus appeared to represent excitation of the primary cortical neurons responding to tactile stimulation of the different body areas.

Nickel alloy steels have been used for many years to contain liquids and gases in the cryogenic and near-cryogenic temperature range. With the advent of large LNG storage facilities and tankers, new attention has been focused on the application of these steels to cryogenic service. The use of ferritic steels in these applications involves not only developing properties in heavier sections that have not been widely used before, but also producing properties in heavy section weldments that are compatible with those of the plate. In order to ensure the strength and toughness that is appropriate for service and to make these steels more economically attractive, complex multistep heat treatments and new alloy compositions have been developed. At the same time, the use of more sophisticated and perhaps more demanding means to evaluate toughness, primarily using fracture mechanics concepts, has also been growing. As a result, there has been a need to determine the toughness design parameters that are appropriate for these new steels and to establish the limits of their usefulness in terms of these newer concepts. The work described in this paper was sponsored by the Pressure Vessel Research Committee of the Welding Research Council and Nippon Steel Corporation in order to explore the use of the newer cryogenic nickel steels in the light of these developments.

Characteristics of a typical male-dominant reaction, dealkylation of n-propoxycoumarin, in rat livers were studied in relation to microsomal testosterone 6 beta-hydroxylase. The depropylation was more than 10-fold higher in the liver of male than female adult rats, but the sex-related difference was eliminated by neonatal castration. Hypophysectomy of adult male rats, which decreased the rates of male-specific P-450-male-dependent reactions, increased the depropylation of propoxycoumarin, while the rate was decreased by either intermittent injection or continuous infusion of human growth hormone to hypophysectomized rats. With regard to age-related difference, microsomal depropylation was detectable at neonate and reached a maximal level at 14 to 20 d of age, but was abruptly diminished only in female rats at puberty. These changes are in good agreement with those of testosterone 6 beta-hydroxylation and the content of a male-specific P-450(6)beta-1/PB-1. In reconstituted systems using extracted microsomal lipids, P-450(6)beta-1/PB-1 and P-450-male catalyzed the depropylation of propoxycoumarin. However, the microsomal depropylation was inhibited by antibodies which recognize P-450(6)beta-1/PB-1, but not P-450-male. These results indicate that microsomal depropylation of propoxycoumarin is catalyzed mainly by a male-specific P-450(6)beta-1/PB-1 in livers of untreated rats.

Neonatal castration completely suppressed the expression of P-450-male and expressed P-450-female; and testosterone treatment in a neonatal period partially reversed the effect of castration, i.e., neonatal imprinting (Kamataki et al., 1984; Waxman et al., 1985). In the present communication, we investigate the reversibility and persistency of neonatal imprinting on the expression of P-450-male and P-450-female. To our surprise, testosterone treatment at adulthood (8 weeks old) caused full expression of P-450-male and restored the activities of 2 alpha- and 16 alpha-testosterone hydroxylases in neonatally castrated rats. The levels of ethylmorphine N-demethylation, propoxycoumarin O-depropylation and benzo(a)pyrene hydroxylation were increased to the levels of adult male rats by adult testosterone-treatment. Moreover, treatment with testosterone of neonatally castrated rats at the age of 19 weeks did not cause a complete recovery of P-450-male content and drug-metabolizing activities. Testosterone administration into neonatal female rats did not significantly alter the contents of sex-dependent cytochrome P-450 and drug and steroid metabolizing activities in adulthood. Additional testosterone treatment in adulthood only slightly affected these parameters. All these results indicate that neonatal androgen imprinting on sex-dependent cytochrome P-450 and drug and steroid metabolizing activities in rat liver microsomes is not a permanent programming process and is modified by the presence and absence of sex-steroid hormones.