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61.
A new method of posterior C1-2 arthrodesis, derived from the W. V. Cone and G. Bertrand, technique (Montreal, 1970) is described with two modifications: (1) the exact measurements of the ideal graft are determined preoperatively, using CT and a sterilized pasteboard horseshoe-shaped model; (2) in the sitting postion, single occipital block graft was cut out microsurgically, using the preoperative model. After decortication of the graft, posterior arches of C1 and 2, and microsurgical excision of the cartilage of the C1-2 lateral joints, the graft was imbedded into the entire C1-2 space, fixed, and tightened using a braid of nylacap yarn. A case report of rotatory luxation and associated atlantoaxial instability in a 10-year-old girl illustrates the excellent functional results of this technique.Presented at the XVII Annual Meeting of the International Society for Pediatric Neurosurgery, Bombay 1989  相似文献   
62.
An impacted ureteric T-tube was removed percutaneously, using an Amplatz goose-neck snare. This new snare has advantages over conventional snares, particularly in situation where atraumatic manipulation is essential. Correspondence to: R. D. Edwards  相似文献   
63.
The pathophysiology of spondylotic cervical myeolopathy is still a matter of discussion. This paper presents a series of 126 patients operated on using a ventral approach. In 47% of the patients only a spondylotic narrowing of the spinal canal was present and in 35% an additional disc herniation was found. In 13% of the cases however a soft disc without spondylotic spures was found and in 5% a dislocation of vertebral bodies. We found a marked male preponderance of 77%, mean age was 51.6 years, ranging from 25–50 years. Most patients were operated on at the levels of C4/5 and C5/6. Observation time covered a period of 3–10 years. The outcome was rated relatively to the preoperative degree of disablement using a questionnaire for the patients and their family doctors. We found a marked difference in the answers, especially in rating deterioration, which was stated by patients in 34%, by physicians only in 12%. Another finding was the time-related out-come. We found best results with 75% improvement and 5% deterioration between 3–6 months postoperatively, with increasing time the results decreased to 33% improvement, 33% identical statys and in 33% a deterioration related to the preoperative status must be noted.  相似文献   
64.
Twelve rats received injections of 5,7-dihydroxytryptamine into the dorsal and median raphe nuclei; 12 rats received sham lesions. The rats were then trained for 60 sessions under a discrete-trials fixed-interval schedule (peak procedure). In half the trials, a reinforcer became available 40 s after trial onset, and the trial was terminated upon reinforcer delivery; the remaining trials were 120 s in duration, and reinforcement did not occur in these trials. Performance during the 120-s trials was characterized by increasing response rate during the first 40 s of the trial, declining response rate between 40 s and 80 s, and a secondary increase in response rate during the final 40 s of the trial. The lesioned group showed a broader spread of the response rate function than the control group (time between attainment of 70% of the peak response rate and subsequent decline of response rate below this level); however, the peak response rate and the time from trial onset until attainment of the peak response rate did not differ significantly between the groups; the spread/peak-time ratio was significantly greater in the lesioned group than in the control group. The levels of 5-hydroxytryptamine (5HT) and 5-hydroxyindoleacetic acid in the parietal cortex, hippocampus, amygdala, nucleus accumbens and hypothalamus were markedly reduced in the lesioned group, but the levels of noradrenaline and dopamine were not significantly affected by the lesion. The results confirm the involvement of 5HTergic function in timing behaviour.  相似文献   
65.
The aim of the present study was to evaluate the effect of age and human papillomavirus (HPV) infection associated cellular changes on the predictive value of cervical cytology. In a group of 671 women with Papanicolaou smears suggesting low grade squamous intraepithelial lesion (LSIL), high grade squamous intraepithelial lesion (HSIL) or invasive cervical cancer, cervical cytology was correlated with the histological finding. Predictive values were calculated and related to severity of the lesion, age and HPV associated changes. The predictive values of Papanicolaou (cervical) smears suggesting LSIL, HSIL and invasive carcinoma were 40%, 86%, and 78%, respectively. A poor predictive value of smears suggesting LSIL was found among older women. HPV associated changes were diagnosed in 80% of women 25 years of age, 66% in the age group 26 to 35 years, 51% in the age group 36 to 45 years and 38% in women aged 46 years (P = 0.03). The presence of HPV associated cellular changes led to a significantly higher number of overdiagnoses (9% with HPV infection compared to 4% without HPV infection) and HPV negative cases were more frequently associated with underdiagnosis (15% without HPV infection compared to 8% with HPV infection,P = 0.0011). This result remained significant after adjustment for age (P = 0.004). Cellular changes associated with HPV infection most frequently occurred in young women. HPV infection should therefore be acknowledged as source of overdiagnosis in the cytological evaluation of SIL especially in woung women.Supported by the Research Grant of the Mayor of Vienna (no. 1045 [to Dr. Kainz])  相似文献   
66.
The aim of this study was to assess the relationships between accident mechanisms as well as initial findings and the long-term course of whiplash injury. A representative sample of 117 consecutive patients referred by primary care physicians was followed-up over 12 months. Fractures or dislocations of the cervical spine, head trauma and pre-existing neurological disorders were exclusion criteria. The interval between the accident and the baseline examination was 7.4 days (SD 4.2 days). Assessment included accident features (e.g. passenger position in the car, head restraint, head position, type of collision), initial symptoms (e.g. intensity and onset of pain, symptoms of neurological dysfunction, multiple symptom score), and signs (restricted neck movement, neurological deficits). At the 1-year examination, patients were divided into an asymptomatic and a symptomatic group and were compared with respect to accident features and baseline findings. Twenty-four percent of patients were still symptomatic after 1 year. Analysing accident mechanisms separately, rotated or inclined head position was the primary feature related to symptom persistence (P=0.005). The symptomatic group scored higher at baseline on the multiple symptom rating (P=0.004) and had a higher incidence of initial headache (P=0.004) and neurological symptoms (P=0.008) together with a higher intensity of headache (P=0.0002) and neck pain (P=0.0009). The following set of initial variables predicted persistence of symptoms at 1 year (logistic regression): intensity of neck pain (P=0.001) and headache (P=0.009), rotated or inclined head position (P=0.02), unpreparedness at the time of impact (P=0.01) and car stationary when hit (P=0.01). In conclusion, accident mechanisms and initial findings suggestive of more severe injury were significantly related to long-term persistence of symptoms after whiplash injury.This study was supported by the Swiss National Science Foundation (project number: 3.883-0.88) and the Swiss Accident Insurance Company (Schweizerische Unfallversicherungsanstalt), Berne  相似文献   
67.
Today some authors consider univentricular repair a contraindication for postoperative cardiac extracorporeal membrane oxygenation (ECMO). The question is whether or not ECMO is indicated as pulmonary support in case of an overwhelming pulmonary infection during the postoperative course after a Norwood procedure. During the prolonged weaning period after a Norwood procedure using a 4 mm aortopulmonary shunt, proven respiratory syncytial virus (RSV) bronchiolitis occurred at the time of expected weaning from artificial ventilation. Venovenous ECMO was able to improve oxygenation, but when pulmonary opacification failed to resolve, ECMO was terminated after 12 days.  相似文献   
68.
The case of a 17-year-old male patient with severe end-stage dilated cardiomyopathy and a large thrombus formation within the cavum of the left ventricle is reported. After an acute thrombectomia combined with a partial left ventriculectomy (Batista procedure), the patient was successfully treated with an appropriate left ventricular assist device (LVAD) system using a centrifugal nonocclusive pump (Biomedicus, Medtronic, Anaheim, CA, U.S.A.). Mechanical support was removed on Day 9, and the patient was discharged from the hospital on Day 19. The effectiveness of emergency mechanical support in patients with very unfavorable prognoses is discussed.  相似文献   
69.
The effects of cocaine on speech sound discriminations was examined to determine whether cocaine's previously demonstrated effect in reducing speech sound discriminability was dependent upon either the type of stimuli employed (simple tones versus complex speech) or the procedure (stimulus detection versus stimulus discrimination). Because of demonstrated similarities in the way that baboons and humans discriminate speech, and in the way the CNS is thought to encode and process speech sounds in these two species, baboons were trained to perform a choice procedure to identify the occurrence of different synthetic vowel sounds (/a/, /æ/, //, /U/, and /љ/). Animals held down a lever and released the lever only when one of four target vowels sounded, and not when a fifth, standard vowel sounded. Acute IM administration of cocaine (0.0032–1.0 mg/kg) produced dose-dependent decreases in vowel discriminability that were mostly due to elevations in false alarms (i.e., releases to the standard vowel) following cocaine. Cocaine also shortened reaction times to the stimuli in two of three baboons, but to a much lesser extent than observed previously. These results suggest that cocaine may interfere with the ability of the CNS to process the acoustic cues in speech sounds, and that the effects of cocaine on reaction times may depend upon the complexity of the reaction time procedure employed.  相似文献   
70.
Uterine cervical cancer is the most common malignancy among females in developing countries, including India. The success of cervical cancer screening programs in North America and Western Europe has been the result of centralized cervical-cytology screening. This is not possible in the villages (n=17,000) of Tamilnadu where 58 percent of females in rural areas are illiterate, health infrastructure is mediocre, and cervical cytology is unknow. The present study was undertaken to examine if the village health nurse (VHN) could be trained quickly to identify a cervical abnormality by visual inspection so that we could down stage the cancer to earlier stages, more amenable to treatment. VHNs also would be trained to take an adequate Pap smear. A total of 101 VHNs were trained in batches and returned to their villages. Within two years, 6,459 engible women in the study area were screened. The agreement between the gynecologists and the VHNs in identifying cancer among those with abnormal cervix was 95 percent, and 80 percent of the Pap smears taken by VHNs were adequate by WHO criteria, making the feasibility study highly successful.Authors are with The Cancer Institute (WIA), Adyar, Madras, Tamil Nadu,India. Address correspondence to Dr Gajalakshmi, Epidemiology Division and Cancer Registry, 18, Sardar Patel Road, Cancer Institute (WIA), Madras-600 036, Tamilnadu, India. This project was funded by the Indian Council of Medical Research, Government of India, New Delhi, India.520 Cancer Causes and Control. Vol 7. 1996  相似文献   
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