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Biomedical subjects

Z Chen

Publications and source records attributed to Z Chen.

At least 991 records · Page 55Linked to original sources
PubMed1997

[Effect of furosemide on the ampullar endolymphatic potential and endolymphatic Ca2+ activity].

The ampullar endolymphatic potential (AEP) and the endolymphatic Ca2+ activity were measured with double-barred Ca2+ selective microelectrodes in the experimental hydrops of guinea pigs. They showed 3.16 +/- 0.42 mV (n = 9) and (4.10 +/- 1.22) x 10(-4) M, respectively. The AEP decreased significantly at about 6 min after intravenous administration of 10 mg/kg furosemide. Its minimal value was 3.04 +/- 0.53 mV at about 40 min. But there was no significant difference between that and the value before injection. The Ca2+ activity increased significantly and reached (7.10 +/- 1.32) x 10(-4) M at about 60 min. The changes indicate that Ca2+ may play an important role in the mechanism of the furosemide test.

Animals↗
PubMed1997

[Treatment of sensorineural hearing loss with delayed onset of vertigo (report of 13 cases)].

Sensorineural hearing loss with delayed onset of vertigo (SHL-DV) is a syndrome consisting of preexisting SHL and subsequent episodes of vertigo. The possible underlying pathophysiology is delayed endolymphatic hydrops. This paper details our clinical experience with 8 patients with SHL-DV caused by otitis media and 6 patients following sudden deafness and hearing loss due to an unknown cause. The average period of onset of vertigo after the occurance of the hearing loss was 22.6 years. The average period of vertigo was 6.2 years. Surgical treatment was performed in 13 patients (14 ears) because of disabling vertigo. Endolymphatic sac decompression was performed in 2 ears, transmastoid labyrinthectomy in 3 ears, gentamycin perfusion of the tympanic cleft in 3 ears, streptomycin perfusion of the labyrinth in 6 ears. Follow-up for 13 patients who had surgery averaged 2.3 years, all patients were cured of their episodic vertigo. Three patients underwent surgical labyrinthectomy suffering with total hearing loss, but aminoglycoside antibiotics induced labyrinthectomy preserving some hearing. We conclude that chemical labyrinthectomy is the therapy of choice for the severe SHL-DV who has serviceable hearing.

Adult↗
PubMed1997

[Endoscopic reconstruction of 192 patients with traumatic urethral stenosis].

We treated traumatic urethral stenosis with endoscopic technique and observed effects. 192 men with traumatic urethral stenosis (47 with anterior urethral stenosis and 145 with posterior urethral stenosis) were treated with hydroelectric shock wave, cold knife, microwave and electroincission through transurethral endoscopy. We punched hole in the centre of the scar with hydroelectric shock waves for long segment urethral complete occlution. 43 patients were treated with obliteration and 50 with endoscopic operation again for 1-3 times. With a mean of 29. 3 months (range 3-60 months) of followup, 187 patients were treated successfully. Endoscopic operation has good effects on traumatic urethral stenosis with smaller trauma, and few complications.

Accidents, Traffic↗
PubMed1997

[A self-designed crooked suturing needle anastomosis in the treatment of posterior urethral strictures or occlusions].

A self-designed crooked suturing needle was described and has been used in the surgical treatment of complicated posttraumatic posterior urethra strictures or occlusions in 27 cases from Mar. 1986 to Feb. 1996. 1-stage transperineal end to end anastomosis of the bulbomenbranous urethra to the prostatic urethra with indeed healthy mucosa to healthy mucosa after scar tissue had been excised was performed with the above mentioned crooked suturing needle. 27 patients were followed up for 3 months to 9.5 years after operation with a satisfactory result of 100% and all voided freely with no sound urethral dilation and no trouble after the removal of the catheter. The erect dysfunction of 5 of the patients after the operation within 1-5 years restored completely.

Adolescent↗
PubMed1997

[Foraminal and extraforaminal lumbar disc herniations].

The severity of the clinical presentations of the foraminal or extraforaminal lumbar disc herniation (FLDH or EFLDH) and its response to conservative treatment were different. In order to make clear the reasons for that and then chose the best method of treatment, two types of FLDH or EFLDH were classified in a group of 23 cases according to the location of the protruded disc shown in the films of CT or MRI. Type I: the disc protruded up to the superior pedicle closely. Type II: the disc protruded laterally mainly with slight moving up. Then two subtypes were made, subtype a: symple FLDH or EFLDH: subtype b: if combined with posterior lateral disc herniation. In total of 23 cases there were 10 of type (I a: 8, I b: 2) and 13 of type II (II a: 7, II b: 6), among of which there were 14 FLDHs and 9 EFLDHs. The clinical presentations and the results of conservative treatment were compared between the two types. The results of statistical analysis showed that the severity of damage to the nerve root and its response to conservative treatment were mainly related to the location of the protruded disc to the superior pedicle rather than the protruded disc in the foramen or extraforamen. All of cases of type I had more severe symptoms and signs, poorer results of conservative treatment and were operated on finally. However some cases of type II only had slight or even no symptoms and signs at all, 50% of the patients in the type II were cured by nonsurgical methods. So it was suggested that the cases of type I be treated surgically mainly, whereas the type II initially be treated conservatively and if failed, go to operation. The approach lateral to the pars interarticularis for the discectomy had more advantages than the other methods and could be applied in most of cases. If combined posterior lateral disc herniation was the main pathologic change in the cases of type II laminectomy with partial facetectomy might be used. The classification is reliable as it is well consisten with the findings of operations. So it is valuable for the guidance of determining the method of nonsurgical or surgical treatment.

Adult↗
PubMed1997

[Influence of preoperative on gastric cancer tissues and cells].

We studied how gastric cancer tissues and cells changed as a result of preoperative chemotherapy. 82 patients with gastric cancer in TNM I-IV stage underwent preoperative selective vascular chemotherapy with routine quantity of FAM. Histological analysis of their postoperative specimens revealed the following results. (1) Cancer tissues necrosed in 56.1% patients. These necroses, due to the chemotherapy, were located around vascular vessels. (2) Cancer cells were found to change with karyopyknosis, karyorrhexis, coagulation and necrosis of cytoplasm. There were invasion of lymphocytes, inflammation edema, and fibroelastosis around cancer cells as well. Changes were also observed in vessels with proliferous intima and thrombus. Most of these changes were grade 2. This paper summarises that preoperative vascular chemotherapy can bring about evident histological and cell changes in different types of gastric cancer. This kind of chemotherapy is recommended as one of integrative treatments to gastric cancer.

Adenocarcinoma↗
PubMed1997

[Angiotensin-converting enzyme gene polymorphism and the clinical pathological features and progression in lupus nephritis].

The renin-angiotensin system (RAS) is now well established as an important determinant in the progression of renal damage. The level of plasma angiotensin converting enzyme (ACE) is genetically determined and this gene effect is associated with insertion (I)/deletion (D) polymorphism in intron 16 of ACE gene. It has been reported that DD genotype of ACE gene is associated with a poor outcome in patients with IgA nephropathy and trend to develop renal damage in diabetic mellitus. In this study, the correlation between ACE gene I/D polymorphism and the clinical features of lupus nephritis (LN) was determined in 144 LN patients and 150 normal controls by PCR. 72 LN patients were followed up for more than two years. It was found that the DD genotype was significantly higher in LN patients than in normal controls (P < 0.01), while the II genotype was much less in LN (P < 0.01). There was no significant difference in DI genotype frequency between LN patients and normal control (P > 0.05). Patients with hematuria, type IV LN, activation of LN, crescentic formation and severe tubulo-interstitial lesions showed an excess of the DI genotype. However, the DD genotype was not associated with the clinical and pathological characteristics of LN. To assess whether ACE genotype influence the progression of LN, we compared the clinical and pathological findings in patients of different genotype subgroups. There was no significant difference in blood pressure, proteinuria, serum creatinine, active index of disease and crescentic formation at presentation among these groups. However, as patients were divided into two groups according to their rate of decline in renal function. We found that patients with progressive renal function damage had a higher frequency of DI genotype than those with stable renal function (P < 0.01). It is conclude that patients with LN the DI genotype was associated with the severity and the poor prognosis in patients with LN.

Adolescent↗
PubMed1997

A study on plasma norepinephrine and epinephrine levels in TCM liver syndromes.

The levels of plasma norepinephrine (NE) and epinephrine (E) were determined by HPLC in 220 patients with various TCM liver syndromes, and in 96 healthy subjects as controls. The plasma NE and E contents were higher in patients with liver excess syndromes, including Ganqi Yujie (GQYJ [symbol: see text]) syndrome, Ganyang Shangkang (GYSK [symbol: see text]) syndrome, Ganhuo Shangyan (GHSY [symbol: see text]) syndrome, and Ganyang Huafeng (GYHF [symbol: see text]) syndrome; while they were lower in patients with liver deficiency syndromes, including Ganqixu (GQX [symbol: see text]) syndrome, Ganxuexu (GXX [symbol: see text]) syndrome, and Ganyinxu (GYX [symbol: see text]) syndrome. Futhermore, when Ganshen Yinxu (GSYX [symbol: see text]) syndrome was turned into GYSK and then into GYHF, the plasma NE and E contents increased in order of precedence; while when GQYJ was turned into Ganyu Pixu (GYPX [symbol: see text]) syndrome, both NE and E contents decreased. The results suggest that the plasma NE and E contents are reliable objective parameters for the study of pathophysiological basis of the liver excess and liver deficiency syndromes, and the liver-kidney and liver-spleen interrelated syndromes.

Adolescent↗
PubMed1997

[Levels of serum G-CSF and supplement of GM-CSF in rats sustaining delayed resuscitation after major burn].

UNLABELLED: Delayed fluid resuscitation of burn shock may lead to infection in early period following major burn injury, resulting in multiple organ failure with high mortality. The change in colony stimulation factors (CSFs) may play a role in developing infection. We assessed the levels of serum granulocyte colony stimulation factor (G-CSF), tumor necrosis factor-alpha (TNF-alpha), phagocytosis of neutrophil and counts of peripheral blood cells of rats with 30% TBSA full thickness burn having either immediate or delayed fluid replacement. We also evaluated the efficacy of granulocyte-macrophage colony-stimulating factor (GM-CSF) in improving survival of rats following burn injury with a superimposed burn wound infection. THE RESULTS: 1. A delayed rise in serum G-CSF was found in delayed resuscitation group, and the levels of serum G-CSF and phagocytosis of neutrophil were lower compared with immediate resuscitation group. 2. Nonsurvival group had lower levels of serum G-CSF and higher content of TNF-alpha compared with survival. 3. Supplement of GM-CSF could significantly improve animal survival with burn wound infection following severe burn shock. CONCLUSION: Decrease in G-CSF production plays a role in developing fatal wound infection after severe burn shock; supplement of GM-CSF is beneficial in improving survival.

Animals↗
PubMed1997

[Anterior segmental maxillary osteotomies (ASMO)].

Anterior segmental maxillary osteotomies (ASMO) were performed with both the Wassmund and downfracture methods in 15 patients and folloned-up regularly for 12 months The postoperative maxillary incisor edge point "Is" movements and complications were examined. The results indicated that the point "Is" movement was 1.66 +/- 0.77 mm postoperatively. No major complications occurred, The stability of anterior segmental maxillary osteotomies was found to be acceptable.

Adult↗
PubMed1997

[Immunobiological significance of S-100 protein positive dendritic cells (S-100+DC) in patients with oral squamous cell carcinoma].

The purpose of this study is to investigate the role and clinical significance of S-100+DC in oral squamous cell carcinoma. Distribution of S-100+DC in the tumor tissues and regional lymph nodes (LN) of 60 patients with oral squamous cell carcinoma was detected by immunohistochemistry (ABC). The results showed that the S-100+DC density in tumor tissues was correlated with the tumor histologic grade (P < 0.05). The density of S-100+DC was significantly higher in regional LN without tumor than those with metastases (P < 0.05). However, there was no difference of S-100+DC in tumor tissues between patients with and without regional LN metastases. The distribution of S-100+DC in tumor tissues and regional LN could be considered as a reference indicator of tumor histologic grade and clinical prognosis of patients.

Adult↗
PubMed1997

[Effect of nitrogen, phosphorus and potassium on the growth of rhizome of Coptis chinensis Franch and its contents of berberine].

It has been found out that the normal growth of Coptis chinensis is heavily affected and both NRA in leaves and berberine contents in rhizome are very low when seedlings are short of nitrogen, phosphorus and potassium. The plants grow especially worse and most of them soon die off when nitrogen is short. The new leaves are smaller both in number and size when phosphorus and potassium are short. Few roots can grow up and easily get old in the solution short of potassium.

Berberine↗
PubMed1997

[Detection of occult tumor cells in resected lymph nodes of patients with stage I carcinoma and its clinico-pathological significance].

OBJECTIVE: Detection of tumor micrometastases in resected lymph nodes of cancer patients to obtain more reliable information concerning nodal status and its clinicopathological importance. METHODS: Paraffin blocks of 3,715 resected lymph nodes from 350 Stage I cancer patients, suffering from NSCLC (n = 94), breast cancer (n = 112), esophageal cancer (n = 115), and vulvar cancer (n = 29), were re-examined by immunohisto-chemical staining, using monoclonal anti-cyokeratins (AE1/AE3), anti-EMA, and polyclonal anti-keratins antibodies. RESULTS: Occult nodal metastases was observed in 113 of 350 cancer patients (32.5%), and in 203 of 3,715 lymph nodes examined. The positive rates both in patients and in lymph nodes were higher in NSCLC than in others. Occult nodal metastasis was seen in 58% of pulmonary squamous-cell carcinomas and 53.8% of adenocarcinomas, while it was seen in 22.5% of esophageal and 10.3% of vulval squamous-cell carcinomas, and in 27.7% of breast adenocarcinomas (P < 0.05). Follow up of a fraction of breast cancer patients showed that the prognosis of patients with positive nodes was worse than that in patients with negative nodes (P < 0.05). CONCLUSION: The data suggested that the immunohistochemical technique can significantly facilitate the detection of micrometastatic tumor cells in lymph nodes. The frequency of occult lymph node metastasis may have significant impact on the prognosis of cancer patients.

Adenocarcinoma↗
PubMed1997

[Effect of hyaluronan perfusion through the round window on the function and morphology of the inner ear in guinea pigs].

UNLABELLED: In order to study the effect of the hyaluronan (HA) on the inner ear, twenty-six guinea pigs were divided into experimental and control groups, the experimental group were perfused with 2% HA 0.2 ml through the left round window. Auditory and vestibular function were investigated before and 5, 14, 28 days after perfusion. The threshold of action potential (AP) response to filtered clicks (0.25-10 kHz) were elevated at 5 days and were improved (at 1-4 kHz) at 14 days after perfusion (P < 0.05). At 28 days all AP response thresholds had returned to normal (P > 0.05). The nystagmus duration induced by caloric test (ENG) had no obviously change comparing with that of preoperation (P > 0.05). All guinea pigs were sacrificed 28 days after operation. The histology of inner ear were examined by means of membranous labyrinth mapping and temporal bone section after celloidin embedding. The morphology of Corti's and vestibular organs were not significantly damaged after perfusion. IN CONCLUSION: 1) 2%HA caused reversible and temporary changes in auditory function of inner ear; 2) 2%HA lacked ototoxic adverse effects, whereas exerted considerable osmotic effects and a slow dehydration of inner ears.

Action Potentials↗
PubMed1997

[Delayed damage of ionizing radiation on the inner ear].

To investigate the feature and mechanism of delayed effect of ionizing radiation on the inner ear, the function and structure of the inner ear of the guinea pigs were observed during 8 month's period after exposure to fractional doses of gamma radiation (2 Gy per day) with a total dose of 60 Gy. Morphological study was performed using light microscopy, transmission and scanning electron microscopy while the function was measured with electrocochleography (ECochG) and electronystagmography (ENG). The results showed that the mean CAP response threshold was 35.67 +/- 6.78 dB before radiation, and 41.17 +/- 7.76 dB, 47.00 +/- 8.82 dB and 71.00 +/- 7.63 dB at 1st day, 3rd month and 8th months after completion of treatment, respectively. No significant change was demonstrated in the auditory responses at the 1st day of radiation (P > 0.05), but there was obvious hearing loss at 3rd and 8th month (P < 0.01). The nystagmus duration induced by ice water (ENG) was 40.00 +/- 5.44 seconds before radiation, 22.71 +/- 7.93 seconds at 8th month after radiation (P < 0.01). Histologic examination at 8th month after radiation revealed atrophy and degeneration of stria vascularis, a reduced number of capillaries, degeneration of endotheliocyte in vessels, outer hair cell and supporting cell of Corti's organ. The percentage of damaged hair cells in basal turn of the cochlea was significantly higher than those of the upper turn. Degeneration of vestibular hair cell was found. It is suggested that radiation from routine radiotherapy doses may result in a delayed impairment of the inner ear. The main mechanism of the radiation damage may be interference of oxygen supply and metabolism of the inner ear by radiation vascular lesion.

Animals↗
PubMed1997

[Investigation of the infectious route of peritonsillar abscess].

One hundred and thirty-one cases of peritonsillar abscess were studied to investigate the pathogenesis and the infectious route. The involved tonsils were resected in 83 patients. The surface of the resected tonsils was smooth and intact, neither ulceration nor pustular sinus was found on the surface of the upper part of these tonsils. There were some inflammatory and/or fibrotic minor salivary glands (Weber's glands) on the top of the quinsy tonsils. The glands adjacent to the tonsils of non-quinsy patients had normal appearance. It suggests that the origin of peritonsillar infection might be the Weber's glands rather than extension from acutely inflamed tonsil.

Adolescent↗
PubMed1997

[Anticarcinogenic effect and hormonal effect of Cordyceps militaris Link].

Cordyceps militaris (CML) has been found good for inhibiting the growth of tumor, prolonging the survival period of mice implanted with S180, inhibiting the growth and metastasis of Lewis pneumonic cancer in the implanted mice, increasing the plasm content of cortisol and testosterone in normal rats, and elevating the weight of sexual organs in normal and castrated rats. CML exerts a malehormone-like effect.

Animals↗