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981.
The notion that the intrauterine contraceptive device (IUCD) has a central, as well as a local action, is examined. Although the IUCD undoubtedly has a local action, certain IUCD related side effects, e.g. galactorrhoea, bloating and premenstrual syndrome and inadequate luteal function can be explained if the IUCD has some central action. The powerful postcoital anti-fertility effect of both copper-bearing and plain plastic IUCDs probably also depends to some extent on a central action. The central action of the IUCD is probably due to initiation of reflex hypothalamic activity following intrauterine reflex stimulation. The hypothalamic response to IUCD insertion consists of release of beta-endorphin accompanied by raised levels of prolactin, vasopressin and oxytocin.  相似文献   
982.
The Brief Symptom Inventory (BSI), a 53-item psychiatric symptom checklist, was administered to 57 alcoholic inpatients on days 2, 10, 18 and 26 of their 28-day stay in an alcoholism rehabilitation unit at a Veterans Administration hospital. The results of the test show a steady decline in the patients' psychiatric symptomatology from week 1 to week 4 with the most dramatic improvement evidenced between weeks 1 and 2.  相似文献   
983.
Existing methods for estimating additional days of hospital stay due to nosocomial infections (NI) have a number of documented limitations. An alternative method described in this paper uses the Appropriateness Evaluation Protocol (AEP) to determine whether each day of acute inpatient care is appropriate based on the need for care of the NI, original cause of hospitalization (OC), or combined NI-OC requirements. Using this method to identify specific days of hospitalization due to Staphylococcus aureus nosocomial infection, we find: 1) length of stay is increased for only a minority of patients (38%); 2) an average of 20 additional days of stay occurred for patients with 1 or more days attributed to NI; and 3) an average of 52% of length of stay of patients with 1 or more days attributed to NI can be attributed to the NI. Application of the AEP-based method is a useful alternative for identifying additional days of stay due to NI.  相似文献   
984.
Residual pancreatic B-cell function was investigated in children with diabetes mellitus in whom classification of the type of disease was difficult at the first visit. Intravenous glucagon tests were performed at the first visit and subsequently, the C-peptide responses compared. Based on our data on a limited number of patients, we propose C-peptide concentrations of 3.0 to 3.5 ng/ml at the peak or at 6 min after injection of glucagon, as the critical level which distinguishes non-insulin dependent from insulin-dependent diabetes mellitus. However, the degree of obesity, clinical stage and other factors also need to be considered in the classification of diabetes mellitus.  相似文献   
985.
Adolescent stress is an emerging area of importance in considerations of the health of young people. Exposure to stress predicts a range of both physical and mental health problems in adolescents and relates, as well, to the initiation of important health risk behaviours. Yet the measurement of stress in adolescents has been as fraught with methodological difficulty as it has been for adults. This paper examines the Adolescent Stress Questionnaire (ASQ) which was developed specifically to address the domain of stressors specific to adolescent experience and looks at three cohorts of responses to this questionnaire over time (1995, 1998 and 2001). It assesses the stability of the original 7‐factor structure of the ASQ over time, and while confirmatory factor analysis indicates that stability to be acceptable, it also suggests that either adolescent stressors themselves, or the language by which they are reported, vary sufficiently over time to warrant the refinement of the instrument. Copyright © 2002 John Wiley & Sons, Ltd.  相似文献   
986.
987.
988.
OBJECTIVE: To determine the aetiological agents and outcome of severe community-acquired pneumonia (SCAP) in children admitted to the paediatric intensive care unit (PICU) at Kalafong Hospital, Pretoria. PATIENTS AND METHODS: An audit was done after a protocol was implemented to identify the aetiological agents in children with life-threatening SCAP admitted to the PICU from the emergency room. The following investigations were done as per protocol: blood culture, culture of the tracheal aspirate, immunofluorescence and culture of the nasopharyngeal aspirate, microscopy and culture of the gastric juice for Mycobacterium tuberculosis, and determination of HIV status. The following data, documented prospectively, were obtained from patient records: date of admission, age, gender, weight, duration of ventilation, duration of stay in the PICU, survival or death, and severity of illness as determined by means of the score for acute neonatal physiology (SNAP) or paediatric risk of mortality (PRISM) score depending on the child's age. RESULTS: Twenty-three children were admitted over a 1-year period (1 November 1994-30 October 1995). Their median age was 10 weeks (range 2 weeks-5 years) and the sex distribution was equal. Two children were HIV-infected. Twenty children received mechanical ventilation for a median period of 6.5 days (range 2-16 days). Aetiological agents were identified in 15/23 children (65%). Respiratory syncytial virus (RSV) was the most common pathogen, identified in 7/23 children, Klebsiella pneumoniae was the most common bacterial pathogen, identified in 5 children (2 blood cultures and 3 tracheal aspirates). Tuberculosis was not diagnosed. The mean PRISM score was similar in survivors and children who died. The case fatality rate was 30%. The 7 children who died had a median arterial oxygen tension/fraction of inspired oxygen (PaO2/FiO2) ratio of 94 (range 32-111) and the 16 survivors had a median ratio of 146 (range 51-252) (P = 0.01) on admission. Both HIV-infected children died and postmortem examination showed a pneumonia due to Pneumocystis carinii and cytomegalovirus. CONCLUSIONS: SCAP occurs in very young children. One or more pathogens were isolated in 65% of cases. Viral pathogens predominated, with RSV being the most common. The yield of positive blood cultures was low at 17%. Streptococcus pneumoniae and Haemophilus influenzae were not found. The case fatality rate was 30% and death was more likely with a low PaO2/FiO2 ratio on admission.  相似文献   
989.
We propose a haphazard branching theory to support the concept of bronchopulmonary malinosculations, and we apply this theory to classify congenital bronchopulmonary vascular malformation (BPVM) based on the anatomical results we have found. Between January 1990 and December 1997, a total of 22 pediatric patients (10 male and 12 female), aged 2 days to 14 years (median, 19.6 months), with congenital BPVM were enrolled in this retrospective study. Study modalities include the clinical features and plain chest films (n = 22) plus at least two of the following: echocardiography (n = 13), barium esophagraphy (n = 2), bronchoscopy (n = 4), contrast bronchography (n = 8), high-resolution direct coronal CT (n = 1) and electron beam or ultrafast CT (n = 1) of the chest, MRI (n = 10), MRA (n = 1), contrast cineangiocardiography (n = 9), surgery (n = 11), or autopsy (n = 2). The salient clinical features were recurrent lung infections in 14 patients, acute respiratory distress in 13, associated cardiovascular malformations in 8, dextroversion in 7, congestive heart failure in 7, dextrocardia in 4, and complex congenital heart diseases in 4. There were abnormal openings (malinosculations) of the pulmonary airway in 20 patients: to an artery in 12, to a vein in 8, and to the lung parenchyma in 9. These 22 patients with congenital BPVM can be classified into bronchial malinosculation (10 cases), arterial malinosculation (2 cases), and bronchoarterial malinosculation (10 cases). Congenital BPVM can be classified in terms of bronchopulmonary malinosculation based upon a haphazard branching theory, in which abnormal communications between two independent systems (primitive foregut system and aortic-pulmonary arch system) occurred coincidentally rather than causally.  相似文献   
990.
Working memory dysfunction is considered to be fundamental to the cognitive and clinical features evident in schizophrenia. Functional neuroimaging studies have begun to elucidate the neurobiological basis of such deficits, however, interpretation of these studies may be confounded by performance impairment, when the cognitive load exceeds the limited response capacity of patients with schizophrenia. In this study, patients were pre-selected on the basis of intact performance on a relatively low-load verbal working memory task, in order to mitigate against performance confounds. Subjects included 20 right-handed male subjects with chronic schizophrenia, and 20 right-handed, age-matched, male healthy controls, without personal or familial psychiatric history. All subjects underwent fMRI scanning whilst performing a verbal n-back task. There were no significant between-group differences in target identification; the patient group showed a significantly increased mean response latency. Both groups demonstrated robust fronto-parietal activation. In the control subjects, the power of functional response was positively correlated with reaction time in bilateral posterior parietal cortex, however, this coupling of behavioural performance and cerebral response was not evident in the patients. This deficit, apparent within the performance capacity of the patients, may represent a fundamental abnormality in schizophrenia, and may compromise performance at higher cognitive loads.  相似文献   
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