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991.
To evaluate the impact of pregnancy on bone, we studied bone turnover at the first (T1) and third (T3) trimester of gestation in 58 adolescents and 28 healthy adolescents who had never been pregnant. Total body (TB) and lumbar spine (LS) bone mineral density (BMD) and body composition were evaluated by dual-energy X-ray absorptiometry in all control patients (C) and after parturition in 28 pregnant patients (G). Paired and unpaired t tests, Mann-Whitney and Pearson correlation tests were used. Bone turnover markers were above the reference range for adult women in more than 80% of the adolescents, with no difference between C and G patients at T1. Increase in urinary N-telopeptide crosslinks of type I collagen and serum bone-specific alkaline phosphatase, markers of bone turnover, was seen during pregnancy ( p < 0.0001). Body composition did not differ between groups, but LS BMD, percentage of expected LS BMD, LS Z-score, percentage of expected TB BMD and TB Z-score were lower in G than C patients ( p < 0.05). TB BMD was positively correlated with LS BMD (r2 = 0.52). The inverse correlations between bone markers and LS BMD suggest that the increased bone turnover during pregnancy probably explains the low bone density after parturition. The impact on future peak bone mass must be studied.  相似文献   
992.
Short latency auditory nerve and brainstem evoked responses (BAERs) and long latency cortical auditory evoked responses (CAERs) in 75 long-term traumatic brain injury (TBI) cases were compared. CAERs were found to be significantly correlated with clinical disability as measured by the Disability Rating Scale, while BAERs were not. Also, BAER patterns were consistently and significantly less abnormal and less sensitive to overall dysfunction than CAER patterns. Findings support previous observations that BAERs have relatively little utility for evaluating in surviving TBI patients the degree of overall brain impairment. In general, long latency AEP patterns are better able to reflect the extent and severity of brain dysfunction and overall clinical condition than are short latency AEP patterns in long-term severe TBI patients, and these patterns should be obtained routinely in the evaluation of such patients.  相似文献   
993.
994.
Higher cerebral dysfunctions such as aphasia, apraxia and agnosia have seldom been reported in multiple sclerosis (MS). 12 year-old right-handed boy felt unsteadiness of the body and headache for several days. Two months later, he had the same episode and complained of visual disturbance, and weakness and sensory disturbance on the face and the extremities. Additionally, he showed amnestic aphasia, acalculia, ideomotor apraxia, finger agnosia and right-left disorientation. Cerebrospinal fluid examinations revealed increases IgG, myelin basic protein and neuron specific enolase (11%, 25 ng/ml and 28.8 ng/ml, respectively). X-ray CT scan and MRI-CT examinations revealed sclerotic lesions on the left parietal white matter and the right mid-brain. The diagnosis was made as MS. He was treated with m-PSL (methyl-prednisolone) pulse therapy for three weeks and consecutively treated with PSL for four weeks. He recovered gradually, but visual disturbance and facial palsy remained. After seven months MRI-CT showed a high signal intensity on the left parietal white matter in spite of the disappearance of the lesion on X-ray CT scan. We suggest that these higher cerebral dysfunctions may result from the lesion of the left parietal white matter which produces a disconnection between each cortical area.  相似文献   
995.
Three children with malignant primary CNS tumors treated with craniospinal radiotherapy developed intraparenchymal hemorrhages a median of 5 years following therapy in sites distant from the primary tumor. Radical surgical procedures disclosed fresh and old hematoma, gliosis, and necrosis in all 3 patients and an aggregation of abnormal microscopic blood vessels in two. No tumor was found. All 3 patients remain in long-term (greater than 10 years) continuous remission.  相似文献   
996.
To gauge whether more stringent civil commitment criteria have led to the criminalization of mentally ill persons, forcing them into jails and prisons instead of treating them, a statewide sample of 1,226 civil commitment candidates in North Carolina was tracked for six months after their commitment hearings. Only 72 sample members were arrested during the period, mostly for burglary or larceny (22 arrests), simple or aggravated assault (17 arrests), and minor offenses (40 arrests), including drunkenness, trespassing, and traffic violations. Fourteen sample members were jailed, and two were sent to prison. The mentally ill who were not involuntarily hospitalized or who were hospitalized for only short periods were seldom arrested; when they were arrested, the charges were generally for nondangerous offenses.  相似文献   
997.
Approximately 400,000 people die outside US hospitals or chronic care facilities each year. While there has been some recent movement towards initiating procedures for prehospital Do Not Resuscitate (DNR) orders, the most common situation in the US is that emergency medical systems (EMS) personnel are not authorized to pronounce patients dead, but are required to attempt resuscitation with all of the modalities at their disposal in virtually all patients. It is unfair and probably unrealistic for EMS personnel to have to make a determination of the validity of a non-standard prehospital DNR order (for example, a living will or a durable power of attorney for health care). Existing prehospital DNR protocols range from being very restrictive in the scope of patients allowed to participate and in their implementation, to those that are more liberal. Potential benefits of prehospital DNR orders include freeing up vital personnel and material for use by those who would more fully benefit, and alleviating the enormous emotional strain on patients, families, EMS personnel, and hospital medical staffs involved in unwanted resuscitations that only prolong the dying process. Given this, prehospital DNR orders present several legal and moral problems. These include proper patient identification, the nature of the document itself, precautions incorporated into a DNR system to prevent misuse, potential liability for EMS and hospital personnel, and potential errors in implementation. Functioning prehospital DNR systems need to include: 1) specific legislation detailing the circumstances in which such a document could be used, the wording of such a document, and protection from liability for those implementing the document's directives; 2) having the currently valid document immediately available to the EMS personnel or base station doctors; and 3) acceptable means of identifying the patient. Relatively few US jurisdictions as yet have a prehospital DNR order system, although it is an idea whose time is overdue. Society's imperative to use available technology has pushed us into a situation where a technique to save those with a potential to continue a meaningful and wanted existence is being used indiscriminately to prolong the agony of death.  相似文献   
998.
The contributors provide an analysis of the conditions and reasons accounting for the acute occupational intoxications in closed environments, which occurred in Moscow in 1986-1989 and resulted in 18 deaths. Proposals are made with regard to a state standard act on the safety rules for working in closed environments with the texts of some paragraphs to this act.  相似文献   
999.
Pattern visual evoked potentials were obtained from 46 patients with definite relapsing/remitting multiple sclerosis, using both a conventional 5-channel occipital array and a 3-D recording technique consisting of three bipolar derivations approximating the three dimensions of space. These three orthogonal wave forms were displayed as a 3-D Lissajous trajectory for each subject. Two of the 15 patients with completely normal conventional pattern VEPs had abnormalities of the orientation of the B-C curvilinear segment of the 3-D pattern VEPs. Delays in the first major occipital positive component (P100) were evident using both techniques; the correlation between P100 latency and the latency of the corresponding trajectory apex was r = 0.99 (P less than 0.01). Post-chiasmal MRI abnormalities were associated with 3-D VEP orientation abnormalities. Three-dimensional pattern VEPs are moderately more sensitive than conventional pattern VEPs at detecting dysfunction posterior to the optic chiasm in demyelinating disease and do not require the use of eccentric fixation to do so.  相似文献   
1000.
We report the clinical, neurophysiological (comprehending electromyography, nerve conduction velocities, and multimodal evoked potentials), histological study of the nerve and muscle and the effect of vitamin E supplement in a 32-year-old case with chronic vitamin E deficiency subsequent to acquired intestinal malabsorption. An early diagnosis for an early treatment is essential in preventing severe neurological deterioration.  相似文献   
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