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1.
The in-vitro permeability of chemically modified tetragastrin with fatty acids through the rat skin was studied. The permeability of these compounds through intact skin and stripped skin of rat was determined with a Franz-type diffusion cell. The permeation of tetragastrin across the intact skin was improved by chemical modification with acetic acid and butyric acid. However, tetragastrin and caproyl-tetragastrin did not permeate across the intact skin up to the end of experiment. The permeation of tetragastrin across the stripped skin was improved by chemical modification, the skin flux of these acyl derivatives being in the order: acetyl > butyroyl > caproyl. The stability of tetragastrin in skin homogenate was also significantly improved by chemical modification with fatty acids. These results suggest that chemical modification of tetragastrin with fatty acids increases its lipophilicity, which makes it permeable across the stratum corneum. Moreover, the chemical modification reduced the degradation of tetragastrin in the viable skin, resulting an increase in permeation of tetragastrin across the skin.  相似文献   
2.
Abstract— Sequential alterations in the binding of [3H]cyclic AMP (cAMP) as an indicator of cAMP-dependent protein kinase (cAMP-DPK) binding activity following transient cerebral ischaemia were studied in the gerbil brain using receptor autoradiography. Transient ischaemia was induced for 10 min. [3H]cAMP binding in the stratum oriens and pyramidale of the hippocampal CA1 sector significantly decreased in the early post-ischaemic stage and showed severe reduction 7 days and 1 month after recirculation. By contrast, [3H]cAMP binding showed no significant alterations in the stratum radiatum of the hippocampal CA1 sector and the stratum pyramidale of the hippocampal CA3 sector up to 48 h after ischaemia. However, the binding in these areas significantly decreased 7 days and 1 month after ischaemia. The stratum lacunosum-moleculare of the hippocampal CA1 sector and dentate gyrus showed no significant changes in [3H]cAMP binding throughout the recirculation period. However, in the dorsolateral part of the striatum, where severe neuronal damage was seen morphologically, [3H]cAMP binding was significantly reduced only one month after ischaemia. These results indicate that marked alteration of intracellular signal transduction precedes neuronal damage in the hippocampal CA1 sector, but not in the striatum. Furthermore, our autoradiographic data suggest that post-ischaemic alteration in [3H]cAMP binding between the hippocampal CA1 sector and striatum may be produced by different mechanisms.  相似文献   
3.
Brain death (BD) is a physiological state defined as complete and irreversible loss of brain function. Organ transplantation from a patient with BD is controversial in Japan because there are two classifications of BD: legal BD in which the organs can be donated and general BD in which the organs cannot be donated. The significance of BD in the terminal phase remains in the realm of scientific debate. As indicated by the increasing number of organ transplants from brain-dead donors, certain clinical diagnosis for determining BD in adults is becoming established. However, regardless of whether or not organ transplantation is involved, there are many unresolved issues regarding BD in children. Here, we will discuss the historical background of BD determination in children, pediatric emergencies and BD, and unresolved issues related to pediatric BD.  相似文献   
4.
Blunt cerebrovascular injury (BCVI) is known to be a potentially fatal complication of cervical spine injury (CSI). Methods for screening the appropriate population remain to be elucidated, especially in Japan. This retrospective study was conducted to predict the risk factors relevant to BCVIs. Among 92 patients with CSI transferred to our institution from April 2007 to March 2012, 40 patients (35 men, 5 women) with neurological deficits and/or significant cervical spine fracture including fracture of transversarium, facet, body, lamina, and spinous process, underwent multi-detector computed tomography angiography (MDCTA) and magnetic resonance angiography (MRA), which identified 10 patients with BCVI [2 carotid artery injuries (BCAIs) and 9 vertebral artery injuries (BVAIs); 1 patient suffered both]. Univariate analyses exploring associations between individual risk factors and BCVI and BVAI were performed using Fisher''s exact test and Chi-square test for dichotomous variables and the unpaired t-test for continuous variables. Multiple logistic regression analyses for BCVI and BVAI were carried out using stepwise methods. On univariate and multivariate analysis, hyperextension injury was significantly associated with BVAI (p = 0.01 and p = 0.02), and subluxation (dislocation of vertebral body > 5 mm) was a significant predictor of BCVI (p = 0.04 and p = 0.03) and BVAI (p = 0.01 and p = 0.01). Prompt evaluation for BCVIs is recommended in CSI patients with hyperextension injury and dislocation of the vertebral body.  相似文献   
5.
研究manoalide对除去生长因子(aFGF和血清)而诱导的血管内皮细胞凋亡的影响.方法:通过细胞形态观察,DNA凝胶电泳及荧光显微术等方法确定manoalide对细胞凋亡的抑制或促进作用.结果:向去除aFGF和血清的培养液中加低浓度的manoalide(1-4μmol·L-1),培养细胞48h,细胞的脱壁和DNA片断化受到抑制;manoalide浓度为7μmol·L-1时,促进细胞脱壁和DNA片断化.结论:低浓度的manoalide(2μmol·L-1)抑制血管内皮细胞凋亡,而较高浓度的manoalide(7μmol·L-1)促进该细胞凋亡.  相似文献   
6.
An indirect immunoperoxidase method was used to study the expression of tissue polypeptide antigen (TPA) and cancer antigen 125 (CA 125) in 47 benign and malignant ovarian tumours. Tissue polypeptide antigen and CA 125 antigen were expressed respectively in 22 (73%) and 16 (53%) of the 30 adenocarcinomas and in five (29%) and four (23%) of the 17 benign tumours. Co-expression of TPA and CA 125 antigen occurred in 12 (40%) malignant and four (23%) benign tumours. Ultrastructurally, TPA and CA 125 antigens were located at the cell surface and microvillous surfaces. Evaluation of combined TPA and CA 125 antigen results revealed a remarkable improvement in the positivity rate and a significant decrease (P less than 0.05) in the negativity rate of ovarian carcinomas as compared with the result of each one separately. These findings provide complementary evidence for the previous results on the plasma levels of TPA and CA 125 antigen and suggest that specific combinations of tumour markers may be more effective for the diagnosis and monitoring of ovarian carcinomas, than the use of any single marker.  相似文献   
7.
Alterations in intracellular calcium homeostasis have been implicated in hepatic injury. Volatile anesthetics modulate the homeostasis of intracellular calcium.
The effects of volatile anesthetics on the hemodynamic and metabolic alterations induced by the calcium ionophore A23187 were studied using isolated liver perfusion in fasted rats. The liver was isolated from 24 hr-fasted male Sprague-Dawley rats, and perfused through the portal vein at a constant pressure of 1.2 kPa in a recirculating perfusion-aeration system. Halothane, isoflurane and sevoflurane were administered at 2%, 3% and 4.4%, respectively.
All volatile anesthetics maintained basal hepatic flow, reduced oxygen consumption, and transiently enhanced net lactate production. A23187 at initial concentrations of 0.8 to 3.2 μM decreased hepatic flow and oxygen consumption in a dose-de pendent manner, and enhanced lactate production. All anesthetics significantly attenuated the decreases in hepatic flow and oxygen consumption after administration of A23187 at 1.6 μM. None of the anesthetics significantly influenced the A23187-induced enhancement of net lactate production.
Volatile anesthetics may attenuate the hepatic vasoconstriction and oxygen debt induced by intracellular calcium overload.  相似文献   
8.
9.
AIM: The objective of the present study was to clarify the indications, usefulness and limitations of ureterorenoscopy. MATERIAL AND METHODS: From January 1998 to June 2004, 72 consecutive patients (48 men and 24 women) with a mean age of 66 years (range, 27-83 years) underwent ureterorenoscopy to diagnose upper urinary tract tumors (UUT). Median follow-up was 24 months (range, 1-73 months). Patients were divided into four subgroups by voided urine cytology and preoperative radiographic findings. Group A (n=11, 15.3%), positive voided urine cytology and positive preoperative radiographic findings; group B (n=5, 6.9%), positive cytology and negative radiographic findings; group C (n=48, 66.7%), negative cytology and positive radiographic findings and group D (n=8, 11.1%), frank hematuria originating from the UUT but negative cytology and negative radiographic findings. We compared the findings of ureterorenoscopic examination and biopsy with the results of retrograde pyelography and cytology of upper tract urine. For each examination, the following diagnostic indices were assessed: sensitivity, specificity, positive-predictive-value (PPV) and negative-predictive-value (NPV) and accuracy. Statistical analysis was performed using McNemar's test. RESULTS: For ureterorenoscopy, sensitivity was 94%, specificity 59%, PPV 72%, NPV 92% and accuracy 76%. For biopsy, sensitivity was 77%, specificity 100%, PPV 100%, NPV 80% and accuracy 88%. Accuracy of ureterorenoscopy tended to be superior to that of retrograde pyelography. Ureterorenoscopy was most useful in the group which consisted of 48 patients (66.7%) with negative voided urine cytology and positive preoperative radiographic findings. This group was the only group in which accuracy of ureterorenoscopic biopsy was superior to that of urine cytology, significantly (P=0.03). CONCLUSION: Results indicated that ureterorenoscopy is most suitable and gives superior accuracy in patients with positive radiographic findings and negative voiding cytology. Ureterorenoscopic biopsy of the upper urinary tract would provide useful information when considering therapeutic strategies, such as nephron-sparing management.  相似文献   
10.
Aldo-keto reductase family 1, member B10 (AKR1B10), an enzyme that converts retinals into retinols is known to detect in non-small cell lung carcinoma (squamous cell- and adeno-carcinomas), but is barely expressed in normal tissues. Since these types of carcinoma occur frequently in the uterus (like in the lung), AKR1B10 may also be overexpressed in two major types of uterine cancer, cervical cancer (CC), and endometrial cancer (EMC). The objective of this study is to investigate AKR1B10 expression in uterine cancer and to analyze its clinical significance. In samples from uterine cancer patients, AKR1B10 was detected in 6 out of 30 (20.0%) CC cases and 6 out of 38 (15.8%) EMC cases. Statistical analysis indicated that AKR1B10 expression was associated with tumor recurrence after surgery and keratinization of squamous cell carcinoma only in CC. Although retinol (a metabolic product by AKR1B10) was observed in the normal epithelium, the molecule was not observed in cancer cells of AKR1B10-positive CC samples suggesting that the recurrence in CC may not depend on the convert of retinals into retinols via AKR1B10, a potential indicator in the management of patients with CC.  相似文献   
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