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81.
An accurate prediction of birth weight during gestation can provide useful information for assessing fetal and newborn health status, enabling the clinician to better predict infant morbidity and mortality. Two previously reported standard methods for birth-weight estimation used data collected in utero to derive formulas by least-squares linear regression. The rationale for the inclusion of particular variables in these equations, however, has not been clearly defined. This study was undertaken to examine the efficacy of some previously used variables as well as some new variables in estimating fetal birth weight. The authors used measurements of femur length, biparietal diameter, and abdominal circumference from 107 fetuses (2500 to 4000 g) as variables to compare the two standard methods of birth-weight estimation. A new formula is presented that is derived from a simple model based on the known relationship between volume and weight. The head is represented as a sphere and the body as a cylinder. This study presents a more systematic approach to formula development in which statistical biases are minimized by examining the underlying distributions of the variables used to predict birth weight.  相似文献   
82.
Thirty-four social drinkers who had referred themselves to the Regional Brain Damage Unit for assessment of the effects of drinking alcohol were compared with 42 volunteer control subjects of equivalent age but with low alcohol intake, using two 'learning' tests — the Rey Auditory Verbal Learning Test (RAVLT) and the Austin Button Maze. The Maze Test gave no evidence of disorder, but the two groups were significantly different on the RAVLT. No abnormalities in standard cognitive tests were apparent. These results suggest that a deficit in learning ability may be an early feature of the brain dysfunction associated with excessive alcohol consumption.  相似文献   
83.
Geographical variations in the incidence of disease are of considerable theoretical and practical importance. It has been claimed that the distribution of acute lymphoblastic leukemia (ALL) phenotypes in Saudi Arabia is different from that recorded in the Western literature. One hundred and twelve (112) patients under 15 years of age, diagnosed as ALL between January 1992 and May 1994 had immunophenotypes performed on their blast cells. Common ALL (cALL) together with pre-B-ALL, formed 86.5% of the total; B-cell 3%, T-cell 6% and null cell 4.5%. These figures are not significantly different from the Western literature. A previous claim from this institution in 1990, that both null and B-cell ALL were significantly increased compared with elsewhere, is not supported by the present figures. Age and sex distribution, and FAB classification, L1 77%, L2 20% and L3 3%, were also of the same order as described elsewhere and, in particular, there was no increase in the frequency of L3 subtype.  相似文献   
84.
OBJECTIVES: To investigate common presentations and expected outcomes in patients with traumatically induced otologic dysfunction. STUDY DESIGN: Retrospective case review of patients who underwent otologic surgery for sequelae of otologic trauma over a 28-year period. Patients were stratified into major and minor trauma cohorts. Major trauma was designated as closed head injury with or without temporal bone fracture; lower-energy insults comprised the minor trauma group. Preoperative and postoperative audiograms were obtained and correlated with extent of injury. SETTING: Tertiary referral center. RESULTS: Major trauma accounted for 44.9 percent of all patients. The remaining 55.1 percent suffered minor trauma, of which simple traumatic tympanic membrane perforation was the most common insult (33.6%). Two hundred twenty-seven cases were performed on 214 patients. Pure tone averages improved a significant 20.8 dB to essentially normal levels postoperatively. CONCLUSION: Regardless of injury extent, surgical rehabilitation of conductive losses attains excellent hearing results that surpass those historically reported for the chronic ear population.  相似文献   
85.
86.
Torque range of motion (TROM) measurements of the metatarsophalangeal joint (MTPJ) of the great toe were made to determine the relationship of joint stiffness and plantar ulceration. Subjects included 20 patients with a history of plantar ulceration of the great toe (GTU), 20 patients with a history of ulceration on the plantar surface of the foot excluding the great toe (NGTU), and 20 normal controls. Peak MTPJ extension was significantly reduced in the GTU group compared to NGTU and control groups (p < 0.0001). The slopes of the TROM and stiffness curves were significantly steeper (p < 0.0001) in the GTU group compared to the control group (p < 0.0001). Results support the hypothesis that stiffness is a factor in plantar ulceration of the great toe.J Orthop Sports Phys Ther 1988;10(5):172-176.  相似文献   
87.
The purpose of the present investigation was to estimate the percentage of asymptomatic subjects who demonstrate an eccentric/concentric torque deficit in leg extension. One hundred and five subjects with a mean age of 23.51 were tested on the KIN-COM(R) dynamometer for maximum eccentric and concentric torque during leg extension using an 80 degrees range of motion at 50 degrees /sec velocity. The subjects were categorized as demonstrating a deficit if at any point in the range of motion the eccentric torque was 85% or less of the corresponding concentric torque. The results revealed that 35-54% of the subjects, depending upon sex or leg tested, demonstrated a deficit. These results suggest that many asymptomatic individuals possess an eccentric/concentric torque deficit. These findings question the validity of previous clinical research indicating that patients with anterior knee pain tend to possess an eccentric/concentric torque deficit and that correction of the deficit alleviates the pain. J Orthop Sports Phys Ther 1989;11(4):142-145.  相似文献   
88.
A community sample of 1106 adults was examined to assess the impact of the doctor-patient relationship on participants' avoidance of treatment for a recognized medical or psychological problem. Of five aspects of participants' previous experience with their physicians, all but waiting time predicted participants' self-reported treatment avoidance. In two logistic regression models participants who felt their physicians listened more to their concerns were less likely to avoid treatment for both medical and psychological problems during the previous 12 months. These findings suggest that patients' perceptions of how they are treated by physicians may help explain why many people delay or avoid healthcare treatment, even when faced with a significant health problem.  相似文献   
89.
A projection from the subthalamic nucleus to the nucleus tegmenti pedunculopontinus has been demonstrated in the rat using retrograde and anterograde transport of horseradish peroxidase. Small, well-localized injections of peroxidase in nucleus pedunculopontinus gave rise to retrogradely labelled cell bodies in the subthalamic nucleus. Injections of peroxidase restricted to the subthalamic nucleus gave terminal labelling in nucleus pedunculopontinus.  相似文献   
90.
It has been speculated that exposure to the chronic stress of racism contributes to the high rates of hypertension among African Americans. Social support may buffer the effects of stress on cardiovascular (CV) health by attenuating stress-induced CV responses that have been linked to hypertension. In this study we investigated the effects of racism and social support on CV reactivity in African American women. Participants showed greater increases in CV and emotional responses while responding and listening to racist provocation. Augmented blood pressure (BP) persisted through recovery following racial stress. Participants receiving no support showed the greatest increases in anger during racist provocation. No significant effects were seen for support on CV reactivity. These results provide some of the first evidence that interactive confrontation with racism elicits significant increases in CV reactivity and emotional distress. Furthermore, individuals receiving less support may be at greater risk for the potentially health-damaging effects of racial stress. These findings may have significant implications for the health of African Americans.  相似文献   
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