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1.
I. Experimental Study on Pathophysiology of Congenital Hydrocephalus It is well known that the major pathogenic mechanism of hydrocephalus is disturbance in cerebrospinal fluid (CSF) circulation. For this reason, many studies on hydrocephalus were intended from the viewpoint of CSF circulation both experimentally and clinically. However, few studies have yet been done on the correlation between the morphological changes and the changes in cerebral energy metabolism in hydrocephalus in vivo. So, in this study, the correlation between the morphological changes and the changes in cerebral energy metabolism in congenital hydrocephalic rats was evaluated experimentally. The morphological changes were estimated by using magnetic resonance imaging (MRI), and the longitudinal relaxation time (T1) of brain tissue at parietal area was also measured. The cerebral energy metabolism was evaluated by using 31P magnetic resonance spectroscopy (MRS) method, and cerebral phospholipid membrane metabolism was also evaluated by using 31P-MRS method. The region of interest (ROI) giving rise to the 31P spectra was placed at fore-brain and parietal area. The PCr/Pi ratio was used as the chosen indicator of cellular bioenergetic status. The PME/beta-ATP ratio and PDE/beta-ATP ratio were used as the chosen indicator of cerebral phospholipid membrane metabolism. The intracellular pH was also evaluated by using 31P-MRS method. Fifty congenital hydrocephalic rats of the HTX strain were used. The animals were divided into two groups--non-hydrocephalic group (n = 15) and hydrocephalic group (n = 35)--. The rats of hydrocephalic group were subdivided into three smaller groups according to the degree of hydrocephalus--mild (n = 15), moderate (n = 10) and severe (n = 10)--, which was estimated by using the cerebro-ventricular ratio (CVR) in coronal section of MRI. Experimental results were as follows: 1) The T1 values in rats of mild, moderate and severe hydrocephalic groups showed significant elongation in comparison with the value in non-hydrocephalic group (p less than 0.01), which indicated the expansion of interstitial edema in cerebral cortex. 2) The correlation between the T1 value and the CVR was evaluated and the correlation coefficient (r) was 0.932 which indicated high correlation. 3) The PCr/Pi ratios in rats of mild, moderate and severe hydrocephalic groups were decreased significantly in comparison with the value in non-hydrocephalic group (p less than 0.01), which demonstrated the disturbance of cerebral energy metabolism in congenital hydrocephalic rats. 4) The PCr/Pi ratio seemed to give the indicative data concerning the prognosis of congenital hydrocephalus.(ABSTRACT TRUNCATED AT 400 WORDS)  相似文献   
2.
It has been claimed that the mechanism of acupuncture analgesia can be explained in part by endogenous opioids. If so, it might be possible to enhance the analgesic effect of acupuncture by the administration of endorphins. If D-phenylalanine (DPA), an inhibitor of the endorphin degrading enzyme, is administered, the analgesic effect of acupuncture should be prolonged due to the increased level of endorphins. From the changes of the pain threshold (PT), we investigated whether or not the pre-administration of DPA can enhance the analgesic effect of acupuncture in humans. In addition, we examined the inhibitory effect of naloxone. 1) In all five subjects whose PT was raised after acupuncture anesthesia (respondents), the rise in PT was significantly prolonged by DPA. 2) Out of 10 subjects whose PT remained almost unchanged after acupuncture anesthesia (non-respondents), the PT was increased by DPA in 5 cases. 3) The rise in PT was most prominent when DPA was administered 30 minutes before the start of acupuncture anesthesia. 4) In all 4 respondents in whom the rise in PT persisted after DPA and acupuncture anesthesia, their raised PT dropped after the intravenous injection of naloxone (10 mg). 5) These findings show that DPA enhances the analgesic effect of acupuncture by the "endorphin mechanism."  相似文献   
3.
Serial changes in N-isopropyl-p[125I]-iodoamphetamine (125I-IMP) in mouse lungs were observed with a confocal laser scanning microscope. Male mice were intravenously injected with 125I-IMP and subjected to autoradiographic procedures 20 minutes, and 3 and 24 hours after injection. Differential interference contrast (DIC) images and confocal images were obtained with a confocal laser scanning microscope, and superimposed images were evaluated. Large numbers of silver grains were observed in the interstitium, bronchioles, and alveolar sacs 20 minutes after the injection, and lamellar distribution of the grains was observed on the ciliary surface. The numbers of silver grains in the interstitium and bronchioles had decreased 3 hours after the injection of 125I-IMP, but the numbers of silver grains in the alveolar spaces had not. Although small numbers of silver grains remained in both the bronchioles and alveolar sacs 24 hours after the injection, most of them had washed out. Confocal laser scanning microscopy is considered to be a useful procedure for studying the distribution of radioisotopes by microautoradiography, because it allows clear autoradiographs to be obtained in which tissues and silver grains are perfectly matched and all silver grains are in focus.  相似文献   
4.
On November 15, 2000, a 60-year-old man was admitted to our hospital with progressive dyspnea and right chest pain. He had a 40-year history of occupational asbestos exposure, which began when he was 20 years old. On admission, his chest radiographs showed pleural effusion on the right side, and asbestos bodies were detected in his sputum. Neither a cytological examination of the pleural effusion nor a histological examination of the pleura by percutaneous pleural biopsy revealed malignant cells. In addition, we could not find any other cause for the pleural effusion (such as tuberculosis, collagen disease, or heart failure). In May 2001, the patient also developed pleural thickening and pain in the right hypochondrium, and he was readmitted to our hospital on May 21, 2001. On readmission, an enhanced abdominal CT showed multiple liver tumors, and percutaneous pleural and liver biopsies were performed. The histological findings in the pleura and liver specimens revealed hypocellular collagen tissues without malignant cells. Thus, we could not determine the main cause either of the pleural effusion or of the patient's disease. However, his condition rapidly deteriorated, and he died on August 12, 2001. At the autopsy, bilateral pleural thickening, predominantly on the right side, and invasion of the lungs were observed. The histological findings in the pleural and hepatic tissues revealed hypocellular collagen fibers with a striate pattern and areas of neoplastic spindle cells. He was diagnosed as having malignant desmoplastic mesothelioma with liver metastasis. Cases of malignant desmoplastic mesothelioma have rarely been reported in Japan.  相似文献   
5.
Abstract: To determine the role of telomere-mediated gene stability in hepatocarcinogenesis, we examined the telomere length of human liver with or without chronic liver diseases and hepatocellular carcinomas (HCC). The mean telomere restriction fragment (TRF) length of normal liver (n=13), chronic hepatitis (n=11), liver cirrhosis (n=24) and HCC (n=24) was 7.8±0.2, 7.1±0.3, 6.4±0.2 and 5.2±0.2 kb, respectively (mean±standard error). TRF length decreased with a progression of chronic liver diseases and that in HCC was significantly shorter than that in other chronic liver diseases (p<0.05). The ratios of TRF length of HCC to that of corresponding surrounding liver of well differentiated (n=7), moderately differentiated (n=10) and poorly differentiated (n=4) HCCs were 0.83±0.06, 0.75±0.05 and 0.98±0.09, respectively. The ratio of poorly differentiated HCC was significantly higher than that of moderately differentiated HCC (p<0.05). A comparison between the size and telomere length ratio of moderately differentiated HCCs revealed a decrease of the ratio with size until it reached 50 mm in diameter. In contrast, the ratio increased as the size enlarged over 50 mm. These findings suggest that the gene stability of the liver cells mediated by the telomere is reduced as chronic liver disease progresses and that telomerase is activated in poorly differentiated HCC and moderately differentiated HCC over 50 mm in diameter.  相似文献   
6.
SETTING: Public health laboratories in Ghana performing tuberculosis (TB) microscopy. OBJECTIVE: To assess the situation of the laboratories in terms of staff strength, technical skills, documentation, biosafety practices, equipment, supplies and disposal systems. DESIGN: Methods used for data collection were interviews using a structured questionnaire, informal observation of laboratory registers, disposal systems and safety measures for sputum handling. RESULTS: Of 114 laboratories visited between 2000 and 2001, 102 (89.5%) were performing TB microscopy. Of the staff working in the laboratories, 9% were medical technologists, 24% laboratory technicians, 37% laboratory assistants and 30% orderlies. Average false-negative and -positive rates were respectively 13% and 14%. Although most of the centres (85.3%) were using the recommended TB laboratory register for recording, in most cases they were not filled in accurately or completely. The majority of the available microscopes had mechanical or optical faults. Availability of other materials for smear preparation and staining ranged from 44% to 82%. The main methods employed for disposal of laboratory waste were burning and burying, but conditions were poor in most of the facilities visited. CONCLUSION: Training of laboratory personnel in TB microscopy and establishment of a quality assurance system are needed in Ghana.  相似文献   
7.
We report a case of duodenal carcinoid tumor accompanied by liver metastasis and lymph node metastases in a patient with von Recklinghausen disease. A 48-year-old woman with von Recklinghausen disease was referred to our hospital because of a submucosal tumor at the ampulla of Vater detected by upper gastrointestinal endoscopy. The lesion was diagnosed as a carcinoid tumor based on the pathology of the biopsy specimen. At operation, although there were liver metastasis on the surface of S3 the liver and regional lymph node metastases, we selected pancreatoduodenectomy with lymph node dissection and enucleation of the liver metastasis. The postoperative course was good and the woman was discharged on postoperative day 33. No recurrence has been seen at 24 months since surgery.  相似文献   
8.
Our aim was to investigate the prognosis of patients with squamous cell carcinoma (SCC) of the gingiva who had preoperative dental operations. We studied 102 patients who were being operated on for SCC of the gingiva with special reference to the effects of preoperative dental operations on the prognosis. Twenty-six patients had dental procedures such as tooth extraction, or incision, or curettage before they visited our hospital, while the remaining 76 had no such interventions. The percentage of patients with advanced T stage disease (T3 or T4) was higher among those who had interventions (17/26, 65%) than among those who had not (35/76, 46%). The difference was not significant. Histopathologically invaded nodes were detected in half the patients in the intervention group (13/26), while they were found in only 18/76 (24%) of those in the no intervention group (p < 0.02). The incidence of nodal metastases with extranodal spread was significantly higher in the intervention group than in the no intervention group (p < 0.05), and those in the intervention group were more likely to develop distant metastases than those in the other group (p < 0.001). The 5-year survival in the two groups was 65% and 92%, respectively (p < 0.01). Preoperative dental operations such as tooth extraction, incision, or curettage possibly lead to regional and distant metastases and therefore a poor prognosis in patients with SCC of the gingiva.  相似文献   
9.
OBJECTIVE: In earlier reports, we found that perfectionism might be involved in the development and/or maintenance of agoraphobia in panic disorder. The present report extends this work by examining the relationship between perfectionism and comorbidity with personality disorders in panic disorder patients with agoraphobia (PDA) and those without agoraphobia (PD). METHOD: We examined comorbidity of personality disorders by Structured Clinical Interview for DSM-III-R Personality Disorders (SCID-II) and assessed perfectionism using multidimensional perfectionism scale in 56 PDA and 42 PD patients. RESULTS: The PDA group met criteria for at least one personality disorder significantly more often than the PD group. With stepwise regression analyses, avoidant and obsessive-compulsive personality disorders emerged as significant indicators of perfectionism in patients with panic disorder. CONCLUSION: These findings suggest that perfectionism in panic disorder patients may be more common in those with comorbid personality disorders, and may be an important target for preventive and therapeutic efforts.  相似文献   
10.
Summary A case of treatment-related leukoencephalopathy is presented. A patient with medulloblastoma was postoperatively treated with craniospinal axis irradiation. One month after irradiation, weekly intrathecal administration of methotrexate was performed 4 times to treat cerebrospinal fluid dissemination of the tumor. Two months after the initiation of intrathecal chemotherapy, the patient became somnolent and developed decerebrate posturing. Magnetic resonance imaging showed diffuse leukoencephalopathy. Positron emission tomography revealed a diffuse decrease in glucose uptake in the deep white matter. Auditory evoked potential also showed diffuse abnormalities, not only in the cerebrum, but also in the brain stem. High dose intravenous leucovorin rescue was attempted without any neurologic improvement.  相似文献   
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