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1. Single-unit activity in the cingulate cortex of the monkey was recorded during the performance of sensorially (visual, auditory, or tactile) triggered or self-paced forelimb key press movements. 2. Microelectrodes were inserted into the broad rostrocaudal expanse of the cingulate cortex, including the upper and lower banks of the cingulate sulcus and the hemispheric medial wall of the cingulate gyrus. 3. A total of 1,042 task-related neurons were examined, the majority of which were related to the execution of the key press movements. In greater than 60% of them, the movement-related activity preceded the activity in the distal flexor muscles. 4. The movement-related neurons were distributed, in two foci, in the posterior and anterior parts of the cingulate cortex, both including the upper and lower banks of the cingulate sulcus. The posterior focus was found to largely overlap the area projecting to the forelimb area of the primary motor cortex by the use of the horseradish peroxidase (HRP) method. 5. About 40% of the cingulate cortical neurons showed equimagnitude responses during the signal-triggered and self-paced movements. The neurons exhibiting a selective or differential response to the self-paced motor task were more frequently observed in the anterior than in the posterior cingulate cortex. 6. The long-lead type of changes in activity, ranging from 500 ms to 2 s, were observed mainly before the self-paced and, much less frequently, before the triggered movements. They were particularly abundant in the anterior cingulate cortex. 7. Only a few of the neurons showed activity time-locked to the onset of the sensory signals. 8. These observations indicate that the anterior and posterior parts of the cingulate cortex are distinct entities participating in the performance of limb movements, even if the movements are simple, such as those in this study.  相似文献   
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We examined the placentas of 12 patients in whom congenital cytomegalovirus CMV infection was suspected from serological and or pathological evaluation. Seven patients died including four intrauterine deaths and five survived. On histological examination, the characteristic inclusion bodies were detected in only three placentas, and villitis with plasma cell infiltration was seen in eight placentas. Immunohistochemistry using a specific antibody against CMV improved the sensitivity of CMV detection 10 cases were positive . With the polymerase chain reaction PCR following the extraction of DNA from formaldehyde-fixed placenta samples, CMV DNA was detected in seven cases. All 12 subjects were diagnosed with CMV infection by additional Southern blot analysis after the PCR. CMV DNA was also detected by an in situ hybridization method in all cases. With current molecular biological techniques the placenta can be reliably used for the diagnosis of congenital CMV infection.  相似文献   
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PURPOSE: The aim of this study was to clarify whether serum hyaluronic acid level (SHA) can reflect the degree of liver fibrosis in biliary atresia (BA). METHODS: SHA was measured in 44 postoperative BA patients at 7 months to 22 years of age, with sandwich enzyme method (Hy-A 100 kit). SHA was compared with T.Bil (group 1, T Bil < 2; group 2, 2 < or = T Bil < 5; group 3, T Bil > or = 5 mg/dL), fibrosis score (0-6, the number of abnormal values among Alb, PT, ChE, T Chol, Fischer's ratio, prealbumin), and histologic grading (0-IV). RESULTS: SHA was 499.8 +/- 332.5 in group 3, significantly higher than in the control, group 1, or group 2. As fibrosis score rose, SHA became higher, and SHA in Score 6 (430.1 +/- 366.1 ng/mL) and score-5 (172.9 +/- 141.8 ng/mL) was significantly higher than in the control and other scores, respectively. As the histologic grade rose, SHA became higher, and SHA in grade IV (444.8 +/- 323.5 ng/mL) and grade III (166.0 +/- 70.3 ng/mL) was significantly higher than in the control or other Grades. Serial change of SHA since before HPE was parallel to the clinical course in 8 patients. CONCLUSION: SHA may be a useful serum marker reflecting the degree of liver fibrosis in BA.  相似文献   
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The functional roles of the primate posterior medial prefrontal cortex have remained largely unknown. Here, we show that this region participates in the regulation of actions in the presence of multiple response tactics. Monkeys performed a forelimb task in which a visual cue required prompt decision of reaching to a left or a right target. The location of the cue was either ipsilateral (concordant) or contralateral (discordant) to the target. As a result of extensive training, the reaction times for the concordant and discordant trials were indistinguishable, indicating that the monkeys developed tactics to overcome the cue-response conflict. Prefrontal neurons exhibited prominent activity when the concordant and discordant trials were randomly presented, requiring rapid selection of a response tactic (reach toward or away from the cue). The following findings indicate that these neurons are involved in the selection of tactics, rather than the selection of action or monitoring of response conflict: (i) The response period activity of neurons in this region disappeared when the monkeys performed the task under the behavioral condition that required a single tactic alone, whereas the action varied across trials. (ii) The neuronal activity was found in the dorsomedial prefrontal cortex but not in the anterior cingulate cortex that has been implicated for the response conflict monitoring. These results suggest that the medial prefrontal cortex participates in the selection of a response tactic that determines an appropriate action. Furthermore, the observation of dynamic, task-dependent neuronal activity necessitates reconsideration of the conventional concept of cortical motor representation.  相似文献   
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ABSTRACT: OBJECTIVE: This study aimed to investigate clinical features of abdominal emergency surgery in elderly patients, and to determine factors predicting mortality in these patients. METHODS: The study population included 94 patients aged 80 years or older who underwent emergency surgery for acute abdominal diseases between 2000 and 2010. Thirty-six patients (38.3%) were male and fifty-eight patients (61.7%) were female (mean age, 85.6 years). Main outcome measures included background of the patient's physical condition (concomitant medical disease, and performance status), cause of disease, morbidity and mortality, and disease scoring system (APACHE II, and POSSUM). Prognostic factors affecting mortality of the patient were also evaluated by univariate analysis using Fisher's exact test and Mann- Whitney U-test, and by multivariate analysis using multiple logistic regression analysis. RESULTS: Of the 94 patients, 71 (75.5%) had a co-existing medical disease; most patients had hypertension (46.8%). The most frequent surgical indications were acute cholecystitis in 23 patients (24.5%), followed by intestinal obstruction in 18 patients (19.1%). Forty-one patients (43.6%) had complications during hospital stay; the most frequent were surgical site infection (SSI) in 21 patients (22.3%) and pneumonia in 12 patients (12.8%). Fifteen patients died (overall mortality, 16%) within 1 month after operation. The most common causes of death were sepsis related to pan-peritonitis in 5 patients (5.3%), and pneumonia in 4 patients (4.3%). Multiple logistic regression analysis showed that time from onset of symptoms to hospital admission and the POSSUM scoring system could be prognostic factors for mortality. CONCLUSIONS: Mortality in elderly patients who underwent emergency surgery for acute abdominal disease can be predicted using the disease scoring system (POSSUM) and on the basis of delay in hospital admission. Keywords.  相似文献   
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Haploinsufficiency of the short stature homeobox-containing (SHOX) gene causes Turner skeletal features, a certain proportion of idiopathic short stature and Leri-Weill dyschondrosteosis (LWD). Here we report a Japanese female with LWD. Her physical growth, skeletal deformity, and endocrine status were recorded longitudinally. She exhibited a constant growth rate (average + 6.2 cm/yr) from 6 to 9 yr old, followed by a downward shift at 10 yr old. Her final height was 135 cm (–4.4 SD for an adult female) and weight was 50.5 kg (–0.3 SD) at 12 yr and 10 mo old. Mesomelia and cubitus valgus were noticed from 2 yr old, and metaphyseal lucency and epiphyseal hypoplasia of the medial side of the distal radius were detected at 6 yr old. Madelung deformity was obvious at 10 yr old, when menarche occurred. Fluorescence in situ hybridization (FISH) analysis demonstrated a single copy of the SHOX gene. The short stature of the patient was thought to be exaggerated by the combination of SHOX haploinsufficiency and relatively early puberty.  相似文献   
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Spontaneous perforation of the bile duct (SPBD) is a rare disease in children. Pancreatico-biliary maljunction (PBM) has been postulated to contribute to its etiology. We have treated three children with SPBD over 30 years, two of whom had PBM. There was one boy and two girls aged 10 months to 2 years with symptoms of abdominal distension, vomiting, abdominal pain, jaundice, and acholic stools. The diagnosis of SPBD was made by paracentesis showing biliary ascites, and primary biliary and intra-abdominal drainage was performed in all cases. The site of perforation was at the connection of the common bile duct (CBD) with the cystic duct in all cases. In two cases reflux of contrast into the pancreatic duct was noted, the common channel was long (17 and 12 mm, respectively), and the bile amylase level in the CBD was abnormally high (50,000 and 67,000 IU/l, respectively). In the third patient there was no reflux of contrast into the pancreatic duct and the bile amylase and trypsin levels in the CBD and gallbladder were not measurable. Thus, SPBD in children may not be due solely to PBM, but may involve multiple mechanisms. Accepted: 11 January 2000  相似文献   
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A series of experiments was carried out both in the hippocampal pyramidal and thalamic ventrobasal neurons to investigate the effect of serotonin level in the brain on slow fluctuations of neuronal discharges. Single neuronal activities were recorded in the following two pharmacologically treated states: (1) a 5-hydroxytryptamine depleted state by p-chlorophenylalanine administration (PCPA phase) and (2) a 5-methoxy-N,N-dimethyltryptamine administered state under the PCPA pretreatment (5-MeODMT phase). The slow fluctuations of neuronal activities in the frequency range of 0.02-1.0 Hz in both nuclei were prominent during the PCPA phase and were similar to those during the paradoxical sleep. In contrast, slow fluctuations were suppressed during the 5-MeODMT phase and neuronal activities during this phase were similar to those during slow wave sleep (SWS). The results show that serotonin in the brain definitely plays a role in stabilizing single neuronal activities.  相似文献   
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