The isolated spinal cord-skin preparation of the newborn rat and effects of some algogenic and analgesic substances

We have developed an isolated spinal cord-skin preparation of the newborn rat. The spinal cord together with a piece of skin connected to the cord by the saphenous nerve was isolated from 1- to 4-day-old rats and separately superfused with artificial cerebrospinal fluid in two neighbouring chambers. Potentials were recorded extracellularly from the third lumbar ventral root. Application of capsaicin (0.5-2 μM) or KCl (60–350 mM) with brief pressure pulses to the perfusion bath of the skin evoked a depolarizing response of 20- to 40-s duration in the ventral root. The response was depressed by [Met⁵]enkcphalin (0.03–3 μM). morphine (0.1–2 μM) and a tachykinin antagonist, [D-Arg¹,D-Trp^7,9,Leu¹¹] substance P (spantide), 1–10 μM), applied to the spinal cord by superfusion, whereas the response was augmented by centrally administered calcitonin gene-related peptide (0.1–0.2 μM) or bicuculline (0.5–1 μM).     

An anisotropy of human tactile sensitivity and its relation to the visual oblique effect

Summary The ability of humans to detect striated stimuli on the distal phalanges was found to be highly anisotropic. Observers were much more sensitive to stripes presented in the proximal-distal orientation than to stripes in any other orientation. This tactile anisotropy was contrasted with the well-known visual anisotropy in which sensitivity is greatest for stripes at the horizontal and vertical orientations. We suggest that both the tactile anisotropy and the visual anisotropy are caused by corresponding anisotropies in the distribution of preferred orientations of orientation-selective neurons with in the respective modalities.     

Effect of different questionnaire formats on reporting of occupational exposures

During an exposure monitoring study, 78 saw maintenance tradesmen were randomly assigned to be interviewed about their exposures using one of two questionnaire formats: open-ended and partly prompted questions about five categories of materials; and detailed prompting about 75 agents. The more open-ended questionnaire elicited fewer exposure responses overall, but more responses about agents not included on the detailed questionnaire. Composite materials and trade name products were more frequently cited as exposures than individual metals or compounds. Validity of responses was ascertained using air measurements (individual metals) or observations of the employees (composite materials). Sums of sensitivities and specificities were very low (near 1.0) for most of the metals for both types of questionnaire. For composite materials, validity improved substantially. Sensitivities with the partly prompted format (0.44–0.85) were always lower than with detailed prompting (0.80–1.00). Specificities were usually, but not always, higher with partial prompting (0.66–0.92) than with detailed prompting (0.18–0.86). Selection of questionnaire format for an epidemiologic study would depend on the likely prevalence of exposure in controls and the effects of trade-offs in sensitivity and specificity.     

凝固酶阴性葡萄球菌检测在慢性前列腺炎中的意义

目的　研究慢性前列腺炎与凝固酶阴性葡萄球菌 (CNS)的关系 ,探讨前列腺液中CNS检测的临床意义。　方法　对 4 2 8例慢性前列腺炎患者采用Meares Stamey四段取样法作前列腺液细菌培养和药敏试验。患者年龄 18～ 4 6岁 ,平均 31岁。病程 3～ 32个月 ,平均 6个月。慢性前列腺炎症状指数 (NIH CPSI)平均 2 3.2分。　结果　 4 2 8例均行细菌培养 ,其中 2 4 8例 (5 7.94 % )分离出细菌。革兰阳性菌 195例 (78.6 3% ) ,其中葡萄球菌 16 0例 (6 4 .5 2 % ,16 0 / 2 4 8) ,CNS 89例 (35 .89% ,89/ 2 4 8) ;CNS中以表皮葡萄球菌为主者 81例 (32 .6 6 % ) ,其次为腐生葡萄球菌 3例和溶血性葡萄球菌 2例 ;NIH CPSI积分与细菌培养结果无明显相关。CNS对常用抗菌药物 (β 内酰胺类、喹诺酮类、氨基糖苷类 )耐药率较高 (5 1.9%～ 10 0 % )。　结论　CNS为慢性前列腺炎的主要致病菌 ,应引起高度重视 ;适时监测前列腺液病原菌及药敏试验对临床诊断和治疗慢性前列腺炎具有重要意义。     

Choreic syndrome and coeliac disease: a hitherto unrecognised association.

Coeliac disease has been associated with a variety of neurological conditions, most frequently cerebellar ataxia and peripheral neuropathy. To date, chorea has not been associated with coeliac disease. We present the case histories of 4 individuals with coeliac disease and chorea (4 women, average age of onset of chorea 61 years). Unexpectedly, most of these patients showed a notable improvement in their motor symptoms after the introduction of a gluten-free diet.     

Detailed Diurnal Rhythm of Sensitivity to Melatonin Injections in Turkish Hamsters, Mesocricetus brandti

A diurnal rhythm of sensitivity to exogenous melatonin was defined in adult male Turkish hamsters, Mesocricetus brandti. Melatonin was administered daily by subcutaneous injections (15 micrograms in 0.1 ml 10% ethanolic saline) for 10 weeks in animals exposed to 16 L:8 D. As in golden and Djungarian hamsters, two periods of melatonin sensitivity were identified. The first, in late afternoon, persisted for 6 hr, from 7 hr to 1 hr before lights off. The second period was briefer, of only 2 hr duration in the late night, terminating at the time of lights on. Melatonin injections given during these sensitive periods promoted testicular regression in most animals; melatonin administered at other times of the day was without effect on testicular function in most animals of these groups. Gonadal regression induced by properly timed melatonin injections was rapid, in many groups nearly complete in 6 to 7 weeks. The results are discussed in relation to the function of pineal melatonin in photoperiodic time measurement in hamsters.     

Interactions between serotonin and substance P in the spinal regulation of nociception

Interactions between 5-hydroxytryptamine (5-HT) and substance P (SP) in the mouse spinal cord were investigated using the tail-flick test and the behavioral response evoked by intrathecal (i.th.) SP or i.th. 5-HT. I.th. injection of 5-HT (20 μg) or the 5-HT₁ receptor agonists(+)-8-hydroxy-2-(di-n-propylamino)tetralin ((+)-8-OH-DPAT) (20 μg) or 5-methoxy-3(1,2,3,6-tetrahydropyridine-4-yl)-1H-indole (RU 24969) (20 μg) markedly inhibited the tail-flick reflex. The effect of these compounds was reduced when SP (5 μg) was given i.th. 55 min, or 55 and 45 min before the agonists. The tail-flick latencies recorded 5 min before injection of a 5-HT agonist were similar in animals treated with SP or vehicle. The changes in the tail-flick test were not due to changes in tail skin temperature since only minimal differences in the skin temperature were recorded between the groups injected with SP or vehicle. I.th. injection of SP (10 ng) or 5-HT (2 μg) produced a similar behavioral response consisting of biting, licking and scratching of the caudal part of the body, indicative of nociceptive stimulation. The responses both to i.th. SP and 5-HT were reduced after i.th. application of SP receptor antagonist [d-Arg¹,d-Trp^7,9,Leu¹¹]-SP (Spantide) (5 μg), as well as 5 min after i.th. injection of the 5-HT receptor antagonist metergoline (4 μg). The data may indicate functional interactions between SP and 5-HT in the mouse spinal cord, which may take place in neurons involved in the processing of nociception.     

应用3H-TdR掺入法对SMMC-7721细胞株药敏试验条件的探讨与应用

目的探讨3H-TdR掺入法在进行SMMC-7721系细胞肿瘤药敏试验实验时的最佳实验条件.方法确定出3H-TdR掺入法药敏实验时的最适细胞浓度、最适实验药物浓度、3H-TdR掺入最适时间;在最适条件下采用3H-TdR掺入法测定肝癌SMMC-7721细胞株对临床常用的9种抗癌药物的敏感性.结果应用3H-TdR掺入法检测肝癌SMMC-7721细胞株药敏试验的最适实验细胞浓度为1×104个/孔,最适试验药物浓度为1×PPC,3H-TdR最适掺入时间为收集细胞前8 h;肝癌SMMC-7721细胞株对DDP、ADM、5-FU、CPT高度敏感,对MTX、VP-16、MMC、NVB低度敏感,对PYM不敏感.结论 3H-TdR掺入法可用于肿瘤药物敏感性测定并确定出它的最适实验条件.     

Cough and converting enzyme inhibitors

Persisting cough developed in three children treated with converting enzyme inhibitors. The symptoms disappeared within 3–7 days after withdrawing medication. These observations in children complement previous reports in adults and indicate that cough may be induced by treatment with these agents.     

一氧化氮在氯胺酮麻醉机制中的作用

目的：了解一氧化氮（ＮＯ）与氯胺酮麻醉作用间的关系。方法：６０只雄性昆明鼠分成４组，Ⅰ组氯胺酮１００ｍｇ／ｋｇ腹腔内注射，Ⅱ组连续３天腹腔内注射Ｎ－硝基左旋精氨酸甲酯（Ｌ－ＮＡＭＥ）５０ｍｇ／ｋｇ后，腹腔内注射氯胺酮１００ｍｇ／ｋｇ，Ⅲ组连续３天腹腔内注射左旋精氨酸３００ｍｇ／ｋｇ后，腹腔内注射氯胺酮１００ｍｇ／ｋｇ，Ⅳ组腹腔内注射氯胺酮１００ｍｇ／ｋｇ后，腹腔１小时内持续给予Ｓ－亚硝酰－Ｎ－乙酰青霉胺（ＳＮＡＰ）３０ｍｇ／ｋｇ。观察各组动物翻正反射丧失和抑制持续时间。结果：各组翻正反射丧失时间无明显差异，为１．３９～２．３０分钟。翻正反射丧失持续时间Ⅰ组４７．７１±５．１７分，Ⅱ组４７．８４±７．９９分，Ⅲ组和Ⅳ组明显比Ⅰ、Ⅱ组短，分别为３１．１４±２．４４和３２．７５±８．１４分（Ｐ＜０．０１）。结论：改变ＮＯ的生成量将影响着氯胺酮引起的小鼠翻正反射抑制的持续时间，ＮＯ在氯胺酮麻醉分子机制中起作用。