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991.
992.
It has been well demonstrated the relationship between the infection with high-risk human papillomavirus (HPVs) genotypes and cervical cancer. In Northeastern Argentina a high incidence of this pathology has been described and therefore a high prevalence of HPV infection is expected. In order to identify HPV genotypes associated with malignant and pre-malignant cervical lesions present in the area, 53 ecto-endo cervical cell specimens obtained from women with cytohistological alterations were studied by a PCR-RFLP technique. Out of 53 patients, 34 (64.2%) were positive for HPV infection, being HPV-16 (32.3%) the most frequently found genotype, followed by HPV-58 (14.7%), -6, -18 and -45 (5.9%), -33, -52, -53, -54, -56, -66, -MM4 and -LVX100 (2.9%). Also 5 cases of infection caused by multiple genotypes were found, which corresponded to 14.7% of the positive cases. Results indicate that besides HPV-16 and -18, the most prevalent high-risk HPV genotypes worldwide, others like -45 and -58 as well as co-infection cases are frequent between women of Northeastern Argentina, and a particular attention should be paid to this circumstance because it could be an epidemiological feature of regional importance and a useful information for a future vaccination program.  相似文献   
993.
Disease states such as diabetes mellitus are known to impair hippocampal glucoregulatory activities, which may contribute to cognitive deficits observed in diabetic subjects. Stress or exposure to stress levels of glucocorticoids (GCs) are also intimately involved in hippocampal glucoregulatory activities and the actions of GCs are often most evident in hyperglycemic states. Glucose transporter (GLUT) expression, activity and translocation represent components of the glucoregulatory activities of the hippocampus that may be disrupted by diabetes and stress. Accordingly, the current study examined the effects of stress, streptozotocin (STZ)-induced diabetes and the combined actions of stress and hyperglycemia upon GLUT8 mRNA expression, protein levels and intracellular trafficking in the rat hippocampus. Short-term stress in euglycemic rats had no effect upon GLUT8 mRNA, while restraint stress normalized diabetes mediated increases in GLUT8 mRNA expression in STZ treated rats. Radioimmunocytochemical analysis revealed that total GLUT8 protein levels were not altered by diabetes, short-term stress or the combined actions of hyperglycemia and stress. However, subcellular compartmentalization of GLUT8 was modulated by stress in that hippocampal GLUT8 protein levels were increased in high-density microsomal (HDM) fractions isolated from rats subjected to stress. In contrast, STZ-diabetes decreased GLUT8 protein levels in the HDM fraction, an effect that was potentiated by stress. Collectively, these results demonstrate that the actions of GCs may be dramatically different in euglycemic and hyperglycemic/insulinopenic states, suggesting that stress may increase hippocampal neuronal responsiveness under normal physiological conditions while increasing hippocampal neuronal vulnerability in pathophysiological settings such as in type 1 diabetes.  相似文献   
994.
The cytoarchitectonic features of the parahippocampal region (PHR) in the guinea pig are described, based on coronal, horizontal, and sagittal 50-microm sections stained for Nissl substance, zinc, parvalbumin, or calbindin. We differentiate between perirhinal (PRC), postrhinal (POR), and entorhinal (ERC) cortices. PRC is divided into areas 35 and 36 occupying the fundus and the dorsal bank of the rhinal fissure, respectively. POR is located caudal to the PRC. POR and area 36 show a dense, clustered cellular layer II and a thinner layer III in comparison to the adjacent neocortex, and they differ from each other with respect to the orientation of the somata of layer VI neurons. Area 35 is characterized by a thin layer II that is not very different from layer III. Layer IV is (dys)granular in area 36 and POR, and is absent in area 35 and ERC. ERC, located ventromedial to the PRC and POR, is subdivided in six fields, of which field 5 is adjacent to area 35. In both area 35 and field 5, no clear differentiation between layers II and III is present. Field 5 shows a darker cellular stain and exhibits a cell-free zone or lamina dissecans between layers III and V. Medial to field 5, an area characterized by large cell clusters in layer II is designated field 4. The latter field is replaced by field 3 rostromedially, which also typically shows clustering of layer II neurons. These cell clusters in field 3, however, are much more constant in size in spacing compared to those in field 4. The caudomedial portion of ERC is subdivided into fields 1, 1', and 2. The latter, characterized by a homogeneous distribution of neurons in all layers with large darkly stained neurons in layer V is positioned rostral to field 1 and caudomedial to fields 4 and 5. In field 1, layers V and VI are thinner, and layer II neurons are smaller then in field 1' and field 2. We conclude that the architectonic features of the guinea pig PHR are comparable to those described in other mammals, particularly the rat.  相似文献   
995.
OBJECTIVE: To develop a method to place a lesion precisely in the subthalamic nucleus (STN) and evaluate its effectiveness. METHODS: A retrospective study of targeting data collected during stereotactic planning to lesion the STN in 31 patients with Parkinson's disease and of results in more than 50 procedures was performed. The targeting method was based on computed tomographic imaging together with semimicroelectrode recording digital processing and electrical stimulation. Two statistical methods were used to correlate initial with final target coordinates and assess the efficacy of the targeting procedure. RESULTS: The anatomic target based on computed tomographic imaging data showed electrical activity in the subthalamus in the first pass in 82% of the procedures. In the remaining 18%, the STN was an average of 1.93 mm away from the nearest trajectory that recorded the STN (range, 1.41-2.24 mm). The average number of trajectories per procedure was 7.2; the location of the first trajectory relative to the center of the nucleus determined by electrical and physiological means (P < 0.01, analysis of variance, Student's t test) was as follows: in the lateral direction, 1.25 +/- 1.15 mm; in the anteroposterior direction, 1.53 +/- 1.31 mm; and in the vertical direction, 0.67 +/- 0.51 mm. The average number of tracts necessary to lesion the STN was two. CONCLUSION: The combination of computed tomographic imaging, semimicroelectrode recording, and microstimulation provides an effective method to identify the STN lesion in parkinsonian patients. The method used for anatomic localization and electrophysiological mapping of the subthalamus was found to be effective in reaching the sensorimotor region of the nucleus. We carried out an accurate determination of the subthalamus location and its volume in the lesioning.  相似文献   
996.
OBJECTIVE: To assess the hypnotic effect of melatonin in patients with primary insomnia. METHOD: Ten patients (mean age 50 yr, range 30-72 yr) who met the DSM-IV criteria for primary insomnia received, in random order, 0.3 mg of melatonin, 1.0 mg of melatonin or placebo 60 minutes before bedtime. A crossover design was used so that each patient received each of the 3 treatments for a 7-day period (with a 5-day washout period between). After each 7-day treatment, night time electroencephalographic (EEG) records were collected, and each morning, subjects completed sleep logs and analogue-visual scales to document the amount and subjective quality of sleep. RESULTS: There were no significant differences in sleep EEG, the amount or subjective quality of sleep or side effects between the placebo, 0.3-mg melatonin or 1.0-mg melatonin treatments. CONCLUSION: Melatonin did not produce any sleep benefit in this sample of patients with primary insomnia.  相似文献   
997.
Sixty-two patients (40 women and 22 men) with multiple sclerosis (MS) were examined with 1.5 tesla magnetic resonance imaging (MRI) of the brain. Information on sexual and sphincteric disturbances has been collected, and data on disability, independence, cognitive performances and psychological functioning have been assessed. Calculations of T1- and T2-lesion load (LL) of total brain, frontal lobes and pons have been performed using a reproducible semiautomated technique. Whole brain, frontal and pontine atrophies were estimated using a normalized measure, the brain parenchymal fraction (BPF), obtained with a computerized interactive program. When comparing patients with and without sexual dysfunction (SD), there were no differences in total brain, frontal and pontine T1- and T2-LL, as well as in measures of whole brain and frontal atrophy. The only significant difference was in the pontine BPF (P = 0.026). In linear multiple regression analysis, SD was associated with depression (R = 0.56, P < 0.001) and, after adjusting for depression and anxiety, with bladder dysfunction (R = 0.43, P = 0.003) and pontine BPF (R = 0.56, P < 0.001). No association between SD and any of the measures of T1- and T2-LL was found. The findings showed a relationship between SD and pontine atrophy, confirmed the correlation of SD with bladder dysfunction and highlighted the role of psychological factors in determining SD.  相似文献   
998.
999.
BACKGROUND: Hepatitis C is a major cause of liver disease worldwide. It has been associated with decreased health-related quality of life (HRQL) and psychiatric symptoms. Our aim was to assess HRQL, depression, and illness understanding in patients with chronic hepatitis C without previous interferon therapy. METHODS: Consecutive patients attending a referral center were enrolled. HRQL was measured using SF-36 questionnaire, depression with Zung self-rating depression scale, and illness understanding with self-applied knowledge test. RESULTS: Of 157 patients enrolled, 112 were female (71%) and 45 male (29%). Ninety-seven patients (61.8%) had cirrhosis. HRQL was significantly decreased in chronic hepatitis C patients compared to historical normal controls in all eight domains of the SF-36 (p < 0.001). In hepatitis C cirrhotic patients, HRQL was significantly lower among Child-Pugh class B and C subjects in domains reflecting physical health (p <0.05). Ninety-two patients (58.6%) had depression that resulted in lower HRQL when compared to nondepressed patients (p <0.05). One hundred fourteen patients (72.6%) had poor illness understanding of hepatitis C. These subjects had significantly lower HRQL scores in six of eight SF-36 domains when compared to patients with better understanding of the disease (p <0.05). CONCLUSIONS: Chronic hepatitis C patients attending a tertiary-referral center had significant decrease in HRQL associated with depression (58.6%) and poor illness understanding (72.6%). Educational programs and their impact on HRQL need to be addressed in detail, particularly for the pre-treatment scenario.  相似文献   
1000.
In 1997, the Centers for Disease Control and Prevention, the Mexican Secretariat of Health, and border health officials began the development of the Border Infectious Disease Surveillance (BIDS) project, a surveillance system for infectious diseases along the U.S.-Mexico border. During a 3-year period, a binational team implemented an active, sentinel surveillance system for hepatitis and febrile exanthems at 13 clinical sites. The network developed surveillance protocols, trained nine surveillance coordinators, established serologic testing at four Mexican border laboratories, and created agreements for data sharing and notification of selected diseases and outbreaks. BIDS facilitated investigations of dengue fever in Texas-Tamaulipas and measles in California-Baja California. BIDS demonstrates that a binational effort with local, state, and federal participation can create a regional surveillance system that crosses an international border. Reducing administrative, infrastructure, and political barriers to cross-border public health collaboration will enhance the effectiveness of disease prevention projects such as BIDS.  相似文献   
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