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1.
Abstract This study was undertaken to elucidate the pathogenesis of the hydrocephalus and aqueductal stenosis induced by intracerebral mumps virus inoculation in suckling hamsters.
Mild ventricular dilatation became apparent after 5 days of inoculation. Focal denuding of the ependymal layer and subsequent aqueductal stenosis were observed by 14 days after inoculation. The virus antigen was detected not only in the ependymal cells and choroid plexus, but also in some neurons in the cerebral cortex, hippocampus, midbrain and cerebellum. In the cerebral aqueduct, the orderly arrangement of the cilialy clusters was destroyed on the 5th day after inoculation. After 10 days, proliferation of GFAP positive cells was noticed around the cerebral aqueduct and subsequently caused aqueductal stenosis. In the advanced state of hydrocephalus, the cerebellum was displaced downward and showed an elongated, atrophic and sleevelike structure similar to the Arnold-Chiari malformation. It was suggested that the extensive damage of the ependymal cilia may account for early ventricular dilatation, and subsequent aqueductal stenosis with glial proliferation is the main cause of the advanced hydrocephalus. It has not yet been determined whether the mumps virus can pass through the human placenta or not. If it can, however, our results strongly suggest that mumps virus infection in the human fetus will cause congenital hydrocephalus.  相似文献   
2.
HtrA2 is up-regulated in the rat testis after experimental cryptorchidism   总被引:3,自引:0,他引:3  
AIM: The aim of the present study was to elucidate the role of high temperature requirement A2 (HtrA2) in germ cell loss in the heat-stressed testis. METHODS: We examined the expression of HtrA2, caspase-9 activity and proteolytic activity of HtrA2 in the rat testis, and their in vivo responses to experimental cryptorchid treatment. RESULTS: Northern analysis revealed the expression of HtrA2 mRNA peaked at days 1 and 7 after cryptorchid treatment. While expression of HtrA2 mRNA was seen in the spermatogonium, spermatocytes and some spermatids in normal adult rat testis, experimental cryptorchidism treatment resulted in a marked increase in its signal intensity in spermatocytes and some spermatids, and the layers of spermatogonium and early primary spermatocytes became negative at days 1 and 7 after the treatment. However, the spermatogonium, Sertoli cells and interstitial cells appeared to have strong intensities at days 14, 28 and 56 after the treatment. Western analysis revealed the expression of HtrA2 protein peaked at day 2 coinciding with the increase of positive spermatogonium, the appearance of protein-positive interstitial cells, and day 28 coinciding with the reappearance of protein-positive interstitial cells. Caspase-9 activity peaked at day 2 and HtrA2 proteolytic activity peaked at day 28. Consequently, the first peak of HtrA2 mRNA expression was followed by the peak of caspase-9 activity and the second peak was followed by the peak of proteolytic activity; however, the second peak of mRNA expression had considerable chronological difference from that of the protein. CONCLUSION: These findings suggest the probabilities that the heat stress results in germ cell death by a caspase-independent manner with the elevation of HtrA2 proteolytic activity, as well as a caspase-dependent manner with the elevation of caspase-9 activity.  相似文献   
3.
Little work has been done with positive emission tomography (PET) in bladder tumors because high urinary excretion of (18)F-FDG makes visualization of the bladder tumor difficult. (11)C-choline has recently been reported as a new tracer which lacks urinary radioactivity. We report the result of (11)C-choline PET in four patients with invasive bladder tumors. In one case, (11)C-choline PET could detect bladder tumor effectively without urinary activity and bone metastasis despite negative bone scintigraphy. On the other hand, an intense accumulation of the tracer in the bladder hampered the interpretation on PET scanning in three patients. The mechanisms of the (11)C-choline accumulation in the bladder were reported to be due to inflammatory and proliferative changes in the mucosa of the bladder from previous catheterization or other factors. Further study is necessary to prove the value of (11)C-choline PET for detecting primary bladder cancer and bone metastasis.  相似文献   
4.
The effects of camostat mesilate, a synthetic serine protease inhibitor on gastric microcirculation and active oxygen species generated by leucocytes from the gastric and jugular veins in the early period after thermal injury were assessed. Male Wistar rats were anaesthetized and a 30% full skin-thickness dorsal burn was inflicted. Camostat mesilate (100 mg/kg) was dissolved in distilled water and administered orally to rats 40 min before thermal injury (the camostat group). The control animals (the vehicle group) were administered distilled water orally. Rolling leucocytes as well as Monastral blue B deposits in venules were observed using in vivo microscopy. Active oxygen species were measured by chemiluminescence. Camostat mesilate decreased the total length of gastric erosion, venular deposits of Monastral blue B, and rolling of leucocytes in venules, and relatively increased luminol-dependent chemiluminescence activity generated by zymosan-stimulated leucocytes 15 min after thermal injury. These results suggest that serine proteases are involved in the formation of gastric erosions and gastric microcirculatory disturbance in the early period after thermal injury.  相似文献   
5.
The aim of this study was to evaluate clinicopathologic characteristics of primary cutaneous Paget's disease of the vulva. Between 1986 and 2005, 22 patients with primary cutaneous Paget's disease of the vulva (type 1) were treated at Tohoku University Hospital. Medical records were reviewed for pathologic diagnosis, patient age, associated neoplasms, type(s) of eczema, symptom duration, treatment, surgical procedures, recurrence, and length of follow-up. Patient age ranged from 51 to 85 years (median 71.5 years). Median duration of symptoms was 24 months (range 2-60 months). Type 1a (intraepithelial) Paget's disease accounted for 18 patients, with 3 type 1b (invasive) cases and 1 type 1c (intraepithelial disease with underlying adenocarcinoma) case. Mean length of follow-up was 53.7 months, and median follow-up was 49 months (range 6-199 months). Only two patients had an associated internal malignancy: T-cell leukemia and breast cancer. Mapping biopsy was performed in 14 of the 18 type 1a cases. All patients were free of disease at the surgical margins and are alive without recurrence. The four patients with type 1b or 1c disease had lymph node metastases. Two has died of disease, and two are alive with no recurrence. The rate of secondary malignancy seems to be low in primary cutaneous Paget's disease of the vulva. Mapping biopsy with careful examination of characteristic skin surface may be useful for surgery of type 1a cases. Inguinal lymphadenectomy is recommended in cases with question of invasion or known underlying adenocarcinoma.  相似文献   
6.
This study aimed to investigate the relationship between working overtime and psychological stress reactions among school teachers. It also evaluated the interaction of overtime work types (on weekdays, on holidays, and bringing work home) and task content (educational, peripheral and both). This cross-sectional study was conducted on Japanese elementary and junior high school teachers. Primary outcome was psychological stress reactions measured with the Brief Job Stress Questionnaire. Participants were asked how long they work overtime on weekdays, holidays, and at home. Participants were also asked whether they engaged in educational tasks and/or peripheral tasks during that overtime work. Multiple linear regression analyses were applied and 6,135 participants were included in the analyses after imputing missing data. Working hours of all three types were significantly correlated with higher psychological stress reactions. Moreover, engaging in both educational and peripheral tasks showed higher psychological stress reactions than in only educational tasks when working overtime on weekdays and holidays. In conclusion, reducing overtime work regardless of work types is crucial for mitigating psychological stress reactions for teachers. It might also be possible to manage the psychological stress reactions by splitting the role of task contents, when working overtime on weekdays and holidays at school.  相似文献   
7.
ABSTRACT. Evaluation of 24-hour endogenous growth hormone (GH) secretion was carried out in 62 children, aged 7-16 years, who did not have classic GH deficiency (GHD). The mean 24-hour GH concentration, determined at 20-minute intervals over 24 hours, was variable, ranging from 1.28 to 11.39 μg/l with a mean of 4.95 ± 2.55 μl (± SD). There was a positive correlation between mean 24-hour GH concentration and plasma insulin-like growth factor I (IGF-I) values ( r = 0.54; p < 0.01). Recombinant human GH, 0.1 IU/kg/day was administered to 30 of the 62 children for 6 months followed by 6 months'observation without treatment. Thereafter, GH was administered at the same dose for a further 6 months to 16 children. The mean height velocities before, during, and after the first treatment period were 4.3 ± 0.9, 7.3 ± 1.9 and 4.9 ± 2.0 cm/year (mean ± SD), respectively. The height velocity during treatment was greater than pre- and post-treatment values ( p < 0.001). The height velocity Increased again during the second treatment period to a mean of 8.5 ± 2.0 cm/year ( p < 0.001). Nine other children were treated continuously in a similar manner for 1 year and their height velocity increased significantly from 4.1 ± 1.4 to 6.0 ± 1.9 cm/year ( p < 0.001). According to our criteria, 29 of the 39 children (74.4%) who were treated for 6-12 months showed a GH-dependent height increase during therapy. There were no differences between the children who responded to GH treatment and those who did not in terms of Chronological age, bone age, plasma IGF-I level, maximal GH level to insulin-induced hypoglycaemia, or mean 24-hour plasma GH concentration. These data indicate that some short children without GHD respond to GH treatment with an increased height velocity. Further investigations are required to determine the effect of GH on final height.  相似文献   
8.
Recombinant somatropin, produced by recombinant DNA technology, was administered by injection in daily doses of 8 IU to six healthy young volunteers. Daily injection for 4 days did not cause any significant change in the results of physical examination, blood count or urinalysis. Non-esterified fatty acid levels increased significantly from 0.45 ± 0.16 to 1.08 ± 0.12 mEq/litre (mean SEM) at 4 hours after the first injection (p<0.001). Plasma IGF-1 levels increased from 0.80 ± 0.14 units/ml to 1.72 ± 0.50, 3.22 ± 1.02, 3.17 ± 1.20 and 3.63 ± 0.78 units/ml at 24 hours after each daily injection for 4 days (p<0.001). Plasma hGH reached peak levels at 3 hours after intramuscular injection of recombinant somatropin, 4 IU, and this peak value was 57.3 ± 2.8 ng/ml. A total of 21 patients with pituitary dwarfism were also treated with recombinant somatropin for 6 months at a dose of 0.5 IU/kg/week. Their heights increased by 2.2–5.0 cm during the 6 months of treatment, which was calculated to be equivalent to 4.4–10.0 cm/year with a mean growth rate of 7.4 ± 0.4 cm/year. Anti-hGH antibody with a titre of 10 was observed in two patients at the end of 6 months of treatment.  相似文献   
9.
The purpose of the present study was to clarify the developmental changes of electroencephalogram (EEG) background activity in term and preterm infants that take place with increasing conceptional age (CA) through an autoregressive (AR) model. Polygraphical EEG recordings were obtained from 76 healthy term and preterm infants with a CA ranging between 31 and 40 weeks. Decreases in total power and component power of δ were noted with CA during burst activity (BA) in quiet sleep (QS) and during active sleep (AS). Increases in total power and component power of δ were noted with CA during interburst interval activity (IBIA) of QS. Regression analysis (RA) of the information amount (IA) indicated a negative correlation with increasing CA in AS and in the monopolar EEG tracings Fp1, C3, O1 and O2 in BA, and a positive correlation in O1 in IBIA. Regression analysis of the IA of δ indicated a negative correlation with increasing CA in AS and in Fp1, C3, O1 and O2 in BA, and a positive correlation in O1 in IBIA. Regression analysis of the IA of δ indicated a negative correlation with increasing CA in BA and AS. These results showed that the high voltage slow wave component changed to a low voltage slow one with development in AS and that BA was longer in duration and lower in power with increasing CA, while IBIA was shorter in duration and higher in power. In conclusion, significant developmental changes occur in all derivatives of AS. Even though the EEG of BA and IBIA change separately, they are followed by EEG of QS in a continuous pattern.  相似文献   
10.
Background: There have been a few evidence‐based studies concerning the relationship between the length of the surveillance interval of colonoscopic examinations and the risk of colorectal cancer (CRC). The aim of the present study was to assess the appropriate interval between endoscopic examinations for CRC screening in a retrospective cohort study. Methods: The cohort included subjects in whom cancer was not detected at the initial endoscopic examination and in whom endoscopic examination(s) was subsequently performed one or more times. The results of the endoscopic examinations performed in the mass screening for CRC between November 1983 and March 1999 were analyzed. The study end point was the detection of CRC and the detection rates of cancer were assessed among those who underwent examinations at various intervals between successive endoscopic examinations. Results: Among the 117 636 cohort subjects, 63 invasive cancer cases and 112 mucosal cancer cases were found. The odds ratio (OR) for invasive cancer was not significantly elevated even when the interval between successive examinations was over 5 years. The OR for mucosal or invasive cancer was significantly elevated among the subjects in whom the interval between successive examinations was over 5 years (OR, 1.71; 95% confidence interval (CI), 1.07–2.73), than among those in whom the interval was 1 year. Conclusions: Since prolongation of the interval between endoscopic examinations of up to 5 years did not result in any change in the cancer risk among persons who are at average risk for CRC, 5 years may be an adequate interval between endoscopic examinations in the mass screening for CRC.  相似文献   
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