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991.
The University of Manchester Medical School has adopted problem-based learning as its main educational method, with a change of emphasis from a biomedical to a biopsychosocial approach. The training of junior medical students in clinical interviewing is intended to reinforce and develop their interpersonal skills. We measured the impact of this new curriculum by assessing two intakes of students covering the period before and after its introduction; a third intake was later added to examine the effect of further curriculum adjustments. 86 students, randomly selected, were videorecorded conducting diagnostic interviews with standardized patients 10 weeks after they had started to learn clinical interviewing. Two instruments were developed--a 23-item communication skills scale and a 13-item information-gathering scale and both showed acceptable inter-rater and test-retest reliability. Communication skills did not differ between years. The total score for information-gathering fell by 13% (95% confidence interval -20 to -6%, P < 0.001) in the first year after introduction of the new educational approach but returned to baseline the following year after further modification of the course. Although the new approach yielded no measurable improvement in the process of communication, assessment 10 weeks after the start of interview training may be too early to permit definitive conclusions. We conclude that it is possible to change to a more patient-centred emphasis in teaching medical interviewing. Some initial loss of information content was rectified by adjustment of the course. Our unfavourable early experience highlights the need to evaluate educational change.  相似文献   
992.
The relationship between growth of the fetal femur and foot length was examined between 14-40 weeks' gestation in 182 normal singleton pregnancies. A significant correlation was demonstrated (r = 0.98; P less than .0001). The femur/foot length ratio was found to be approximately 1 throughout this age range. The fifth and 95th percentile confidence intervals of the femur/foot length ratio versus gestational age were then defined. The femur/foot length ratio was also measured directly in 12 fetuses after second-trimester abortion; these measurements compared favorably with the ultrasound femur/foot length ratio nomogram. The discriminatory power of the femur/foot length ratio chart to differentiate fetuses with skeletal dysplasias from those with pseudo-limb reduction due to constitutional factors or intrauterine growth retardation (IUGR) was tested in 16 sequential cases with femur measurements below the fifth percentile. Two cases suspected of having symmetrical IUGR and five cases suspected of being constitutionally small were found to have femur/foot length ratios within the 90th percentile range. Limb reduction deformities were suspected in the nine remaining cases, and the femur/foot length ratios in these fetuses were all found to be less than the fifth percentile. The femur/foot length ratio nomogram appears to be a useful parameter to help differentiate fetuses that have dysplastic limb reduction from those whose limbs are short because of constitutional factors or IUGR.  相似文献   
993.
In order to study the effect of cycle length on the pregnancy rate in an in vitro fertilization and embryo transfer (IVF-ET) program, 173 consecutive patients were divided into short menstrual cycle (mode 26 days or less) and normal cycle (mode 27 days or more) groups. Patients were randomly allocated to one of two treatments, commencing ovarian stimulation with human menopausal gonadotropin (hMG) on either day 2 or day 4 of their cycle. The number of oocytes retrieved and embryos transferred did not differ significantly. The amount of hMG used and day of human chorionic gonadotrophin administration both differed significantly (P less than 0.01) between regimens but was independent of cycle length. Both the clinical pregnancy rate (30.2% versus 9.4%, P less than 0.05) and the number of cleaved embryos giving rise to gestation sacs (16% versus 3.4%, P less than 0.02) was significantly higher in patients with a normal cycle length. Mode cycle length has a significant bearing on the outcome of IVF-ET cycles.  相似文献   
994.
In the study period (June 1984 to December 1986), 2232 cycles were stimulated in 1294 patients. Ultrasound-directed oocyte recovery (UDOR) was performed as an ambulatory procedure in 1737 (77.8%) cycles, resulting in 1375 embryos transfers (ET). Age, etiology, menstrual cycle length, number of oocytes collected, and number of embryos transferred were important determinants of the outcome. The number of attempts at in vitro fertilization did not affect the clinical pregnancy rate (CPR). In patients receiving four embryos, the CPR appeared to be highest when up to seven embryos were available for transfer. The fertilization rate in an individual cycle had a good prognostic value, the implantation rate being highest when 7 to 9 oocytes were retrieved and greater than 60% of these were fertilized. When 10 or more oocytes were collected, the implantation rate showed a progressive decline, regardless of the fertilization rate. Furthermore, multiple pregnancies failed to occur when greater than 12 oocytes were retrieved or more than eight embryos were available for transfer. These data suggest that, in excessively stimulated cycles, the quality of oocytes and embryos or uterine receptiveness may be suboptimal, and the transfer of more than four embryos is unlikely to increase the success rate.  相似文献   
995.
996.
This paper reviews the incidence and pathology of liver tumours in children in the State of Victoria from 1955 to 1987. Seventy-four cases were found and are believed to represent all liver tumours in the State during that time. There were 29 benign and 45 malignant tumours. The benign tumours comprised 13 haemangiomas, 12 mesenchymal hamartomas, and 4 epithelial lesions. The malignant tumours were 30 hepatoblastomas, 8 embryonal sarcomas, 4 hepatocellular carcinomas, and 3 miscellaneous tumours. The haemangiomas were more commonly cavernous. Four were associated with skin lesions and 3 of these were capillary in type. Mesenchymal hamartomas varied from predominantly solid to predominantly cystic. All, however, contained hamartomatous collections of ducts and liver cells irregularly arranged in dense fibrous tissue. The commonest malignant tumour was hepatoblastoma, and there were 15 of predominantly epithelial type and 15 of mixed epithelial and mesenchymal type. The 8 undifferentiated sarcomas of embryonal pattern were characterised by pleomorphism of cells, bizarre giant cells, and extensive mucoid stromal change. Four examples of hepatocellular carcinoma were seen. All were multifocal and no further case has been seen for the last 15 years. The 3 miscellaneous tumours were gastrinoma, rhabdoid tumour, and myofibroblastic tumour of uncertain histogenesis. Incidence was calculated for the period of review. The rate for benign tumours was 0.81 per million children per year and for malignant tumours 1.33 per million children per year. Surgery for hepatobalstoma was shown to be the most important factor in improving survival.  相似文献   
997.
One hundred and two cases of neonatal cancers, representing 2% of all paediatric malignancies, were seen during a 60 year period at The Hospital for Sick Children, Toronto, Canada. The neonatal cancers included neuroblastoma (47%), retinoblastoma (17%), soft tissue sarcoma (12%), central nervous system tumours (9%), leukaemia (8%), and a few cases of Wilms'' tumour, liver tumour, and miscellaneous tumours. The overall mortality from disease was 41%. Patients with retinoblastoma, Wilms'' tumour, and neuroblastoma had the best prognosis. Forty three patients (42%) survived their neonatal cancers; all were treated with surgery or radiochemotherapy, or both, but none suffered long term major handicaps as a result of treatment. There was one instance of second malignancy of the thyroid gland induced by radiation. We conclude that although neonatal cancers are difficult management problems, many patients can be cured. Physicians should discuss with parents the possible risks associated with treatment before treatment is begun.  相似文献   
998.
The status of children's psychopharmacology is reviewed in the context of differences from its adult counterpart. An overview is presented of recent psychopharmacological developments in the treatment of childhood behavioral disorders. The disorders are grouped according to the potential usefulness of medication. The focus is on clinical efficacy and safety of drug usage. The effect of psychoactive drugs on cognitive functions in the laboratory is referred to, as well as the value of determining drug levels in clinical practice. It is concluded that drug administration in isolation is not the treatment of choice. Drug therapy is a valuable adjunct, however, to psychosocial interventions.  相似文献   
999.
Gonadal function was studied in two groups of children previously treated for medulloblastoma with surgery followed by postoperative craniospinal irradiation. In group 1 but not in group 2, the children also received adjuvant chemotherapy for one to two years. All children in group 1 received a nitrosourea (BCNU or CCNU), plus vincristine in four and procarbazine in three patients. The nine children in group 1 showed clinical and biochemical evidence of gonadal damage with elevated serum FSH concentrations and, in the boys, small testes for their stage of pubertal development. In group 2 (n = 8), each child had completed pubertal development normally, the boys had adult sized testes and the girls regular menses. Gonadotropin values were normal in all eight children. We conclude that nitrosoureas were responsible for the gonadal damage in the children in group 1, with procarbazine also contributing to the damage in the three children who received this drug. In view of the limited proved value of adjuvant chemotherapy with nitrosoureas in the treatment of medulloblastoma, recognition of this serious complication of cytotoxic drug therapy may necessitate reassessing in which subgroups of children with medulloblastoma the benefits of adjuvant chemotherapy outweight the complications.  相似文献   
1000.
Studies were undertaken in the rhesus monkey to determine whether development of a dominant ovarian follicle could be repeatedly arrested by the administration of a progestin on day 7 of the menstrual cycle, and then every 7 days thereafter regardless of menstrual bleeding history. Progesterone (7.5 mg), norethisterone (1.5 mg), and 17 alpha-ethinyl-17 beta-methoxy-7 alpha-methyl-4-estren-3-one (1.0 or 1.5 mg) effectively inhibited ovulation when injected intramuscularly once a week for 8 weeks. Orally administered STS 557 (17 alpha-cyanomethyl-17 beta-hydroxy-4,9-estradien-3-one, 1.0 mg) also inhibited ovulation. Two structurally related steroids (17 beta-methoxy-4-estren-3-one, 1.0 mg; and 17 beta-methoxy-7 alpha-methyl-4-estren-3-one, 1.5 mg) did not inhibit ovulation when given intramuscularly at the indicated doses. Although weekly administration of certain progestins effectively arrested follicular development and inhibited ovulation in the primate, the treatment was accompanied by disturbances in menstrual bleeding patterns.  相似文献   
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