1993年 · 第106卷第04期

In a comparison of the spontaneously hypertensive rat (SHR) with Wistar-Kyoto (WKY) and Sprague Dawley (SD) rats, it was shown that pertussis toxin (PTX) lowers the blood pressure of the SH but not WKY or SD rats. Sympathetic nerve stimulation (SNS), via the pithing rod, the nitric oxide NO)-synthase inhibitor N"-Nitro-L-arginine methyl ester L-NAME) and the pressor response to infusion of AVP were also observed. The results indicate that a G-protein(s) population and/or function may be altered in the vascular smooth muscle of SH rats. This dysfunction may contribute to the heightened pressor responsiveness of the SHR vasculature to SNS and arginine vasopressin (AVP) and the increased sensitivity to the hypotensive effects of nifedipine. NO-synthase activity also appears to be increased in the SHR, suggesting that this increase should reflect a compensatory change due to the elevation of BP in SHR.

Endothelium-derived nitric oxide (EDNO) is an important vasodilator substance produced by the vascular endothelium. The present in vivo and in vitro study is aimed at evaluating its role in vascular regulation and its interactions with norepinephrine (NE), endothelin-1 (ET) and superoxide anion. In male anesthetized wistar rats, inhibition of the in vivo EDNO pathway with L-NAME (an established specific inhibitor of EDNO synthesis, 1-4 (mg/kg, iv bolus) provoked sustained, dose-dependent hypertensive responses (mean arterial pressure increased 45±1.5% over baseline for more than 60 minutes at a dose of 4 mg/kg, mean±Sx, which was completely reversed by L-arginine, the normal substrate for EDNO synthesis). In the in vitro study on rat aortic rings, blocking the endothelial production of EDNO with L-NAME (10-4 M), caused the most prominent enhancement of the contractile responses to NE (increased maximal responses and lowered EC50), a smaller enhancement of contraction to ET and minimal modification of the vasoconstrictive effects of superoxide anion. L-arginine (10-4 M), on the contrary, slightly attenuated the contraction to NE and ET but without the contraction to superoxide anion. The present study confirms that EDNO system represents one of the most important physiological depressor mechanisms in vivo, and indicates that EDNO is an important, differential antagonistic mechanism against the vasoconstrictors. It is also demonstrated that L-arginine availability is generally not the rate-limiting step in the in vivo generation of EDNO. The implications of the results were discussed.

To determine the prognostic importance of pulsed Doppler-derived left ventricular diastolic filling velocity profiles and the relationship between Doppler variables and clinical functional status, the follow-up outcome of 58 patients with dilated cardiomyopathy and symptoms of left ventricular dysfunction was analysed. During a mean follow-up period of 31.2±12.8 months, 23 died of either progressive pump failure or sudden death. Peak early filling velocity (E) was higher and late atrial filling velocity (A) lower in nonsurvivors than in survivors. The E/A ratio was higher and the deceleration time (DT) of early diastole shorter in nonsurvivors. The mortality was significantly higher in patients with an E/A ratio>2 or a DT<150 ms than in those without. Repeated Doppler echocardiographic examinations in 31 of 35 survivors after intense treatment showed decreased E, increased A, reduced E/A ratio and prolonged DT in 18 patients with clinical functional improvement, whereas these measurements were unaltered in the remaining 13 patients whose functional status was unchanged or deteriorated. This study suggests that pulsed Doppler-derived left ventricular diastolic filling variables may be important predictors of outcome in dilated cardiomyopathy and provide useful measures in observing the effects of therapy during long-term follow-up of the patients.

The effect of changes of airway inflammation on airway nonspecific reactivity were studied in 29 patients with chronic asthma. Detailed examinations of bronchial lavage (BAL) fluid and airway responses to histamine, propranolol and exercise were performed before and after treatment. The patients treated with steroids had significant improvements in parameters of BAL fluid cells and mediators with consistent changes of decreasing airway reactivities to propranolol and exercise after treatment. Whereas no significant changes occurred in the patients treated with B2-agonist either in inflammatory parameters or airway responses. On the other hand, airway response to histamine changed little in all asthmatic patients. Our study implied that inhibiting the airway inflammation in asthmatics may lead to marked decrease of airway response to non-mediator stimuli but fail to attenuate bronchial hyperresponse to mediator stimuli like histamine.

From June 1983 to December 1991, 21 adult patients with intermediate or high-grade malignant lymphoma (ML) were treated by ablative chemoradiotherapy, including vincristine, cytosine arabinoside, BCNU and cyclophosphamide plus total lymphoid or body irradiation with boost irradiation over bulky and original tumor areas (Hd-VCCA+TL(B) I) together with autologous bone marrow transplantation (ABMT). Five patients were in advanced stage, 2 in drug-resistant relapse, 6 in drug sensitive relapse, 6 in first complete remission (CR1) and 2 in CR2. One with marrow involvement at ABMT. The 8-year disease-free survival after ABMT in patients with Hodgkin's disease (HD) and non-Hodgkin's lymphoma (NHL) in 89% and 63%, respectively, with a median follow-up up to 34 months. This study demonstrated that our Hd-VCCA+TL(B) I regimen and ABMT performed early in CR or drug-sensitive relapse of adult poor prognosis lymphoma, may potentially cure more than 70% of them. The toxicity of the present treatment is tolerable. The results confirm the value of ABMT in the treatment of adult ML, and suggest that it is necessary to purge the residual tumor cells in the bone marrow at ABMT in patients with marrow infiltration, or lymphoblastic lymphoma.

Examination of eosinophilia of CSF in 17 cases with cerebral cysticercosis was reported. Eosinophilia was observed in 9 of the 17 cases (52.9%), and its significance in the early diagnosis and in immune response was discussed.

During a 17-year period, 23 patients with primary tracheal tumors underwent surgical treatment in the Department of Thoracic Surgery, PUMC Hospital (11 cases of benign tumor of the trachea, 12 cases of low malignancies). Fourteen times of apoxesis were performed in 11 patients with benign tumors who were followed up for an average of 6.3 years. Fifteen operations were performed in 12 cases including local resection of the tracheal wall and tumor in 4, and curettage of tumor plus electric cauterization on the basis in 10. Eight of 9 patients with adenoid cystic carcinoma received postoperative adjuvant irradiation, with a 5-year postoperative survival rate of 75% (6/8) and 3 cases survived over ten years. The desirability of apoxesis and local resection of tracheal tumor is discussed. The authors suggest that these two surgical patterns can be regarded as a simple and effective treatment for patients with primary tracheal tumors.

The recurrent rate of herpes simplex keratitis (HSK) was 4.17% after penetrating keratoplasty (PKP) was performed in 216 patients with HSK; the mean period of follow-up was 6.5 years. Immunohistochemical technique showed that HSV-1 antigens were present in the corneal stroma of rabbit eyes up to 45 days after primary corneal infection had subsided. No positive staining of HSV antigen was found in the sections of 18 human corneal buttons with quiescent herpetic lesions. However, after cocultured with primary rabbit kidney (PRK) cells, positive staining was noted in 6/9 human corneal buttons, and some PRK cells developed cytopathic effect. The detection of the sensitivity of cultured corneal cells to HSV-1 infection demonstrated that keratocytes were the most sensitive cells. These results suggest that the cornea may be another site of HSV-1 latency in addition to the trigeminal ganglion.

A group of 433 neonates with pneumonia were studied through the monitoring of audiology on the basis of epidemiology in perineonatal hearing impairment and applied auditory evoked potentials. The results showed that 29 cases had a threshold of more than 30 dBnHL in primary auditory brainstem response test (6.7%), and 19 cases with threshold, more than 40 dBnHL in primary 40Hz-auditory event related potential (40Hz-AERP) test (4.4%). The follow-up between the 3rd and 12th month after the initial test demonstrated that 12 cases had hearing impairment to various degrees.

Thirty biopsies from female genital condylomata were examined by scanning electron microscopy (SEM) and transmission electron microscopy (TEM) to study structural characteristics and typing of condylomata. It was found that cytoplasmic clearing was marked in acuminate condylomata, diffuse interstitial and epithelial proliferation in nodular condylomata (flat condylomata), and invagination of the lesions into the interstitial tissue or glandular ducts in endophytic condylomata. In nodular condylomata, SEM also showed some structural features similar to those of intra-epithelial neoplasia. Microridges on the surface of squamous cells had villiform of granular changes. On the surface of a percentage of squamous or columnar cells, there were holes with a diameter of about 3 to 5 μm. A number of giant cells were seen among other cells. The cervical squamatization zone contained groups of special cells covered with dense microvilli. TEM of nodular condylomata revealed some pictures resembling active proliferation of tumor cells, such as enlarged or irregular nuclei (large N/C ratio), evaginated or invaginated nuclear membranes, condensed chromatin attached to the inner part of the nuclear membrane, transparent nucleoplasm, and frequent nucleosomes and karyokinesis. Virus particles with the morphological characteristics of HPV (naked hexagon-like particles with an average diameter of 45-50 nm) were seen in some nuclei with markedly condensed chromatin. It is suggested that HPV-induced genital condylomata, especially nodular one (flat condylomata), entail a potential progression to malignancy.

This article reviews, for authors publishing in the Chinese literature, the characteristics of MEDLINE users, the format of MEDLINE citations and the main retrieval strategies used with the system. References were retrieved and data collected through MEDLINE searches of the database 1988-June 1992. Thirty-six indexed journals from the People's Republic of China (PRC) were analyzed. The items of a MEDLINE citation are described. Titles of Chinese journals are listed in English as well as Chinese in the annual "List of Serials Indexed" of Index Medicus. Articles from journals in the PRC are indexed at the China MEDLARS Center, Beijing, PRC. For the 36 journals analyzed, 12,530 citations appeared in MEDLINE during the search period. Basic search strategies are described. Users doing author searches may have difficulties with common Chinese surnames, especially if only one given name initial is used. Journal searches of specialty journals, as well as address field searches for publications from a particular institution, may be helpful to scientists planning a visit to China. Effective use of MEDLINE has become an opportunity and responsibility for scientists and physicians over the world. Suggestions for preparation of English titles and abstracts to assure optimal information transfer and retrieval efficiency are: think about your audience; do not waste words; include key features in the title; be consistent with names and affiliations; use MeSH terms; include important non-MeSH terms in text; use structured abstracts; and obtain MEDLINE printouts of your own citations.

The effect of Cordyceps sinensis crystal (CS-Cr) on stimulating proliferation of erythroid progenitor cells (CFU-E and BFU-E) in LACA mouse marrow in vivo and in vitro by methyl cellulose gel culture system is reported. The numbers of CFU-E and BFU-E were increased after 5 consecutive daily treatment with 100, 150 and 200 mg/kg of CS-Cr with a peak at 150 mg/kg. Higher doses (>150 mg/kg) of CS-Cr resulted in a reduction of the peak of CFU-E and BFU-E and then, the numbers returned to the control level with increased doses. The cytosine arabinoside (Ara-C) suicide test showed significant increases in the percentage of CFU-E and BFU-E in S-phase after CS-Cr treatment. Pretreatment of mice with CS-Cr could protect CFU-E and BFU-E against the cytotoxic agent--harringtonine. Addition of CS-Cr to culture system also promoted the generation of CFU-E and BFU-E at concentrations of 150-200 micrograms/ml in vitro. With a liquid culture technique, a stimulatory action of CS-Cr on fibroblast colony-forming units (CFU-F) proliferation was seen in vivo and in vitro.