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71.
PURPOSE: Childhood sexual abuse (CSA) is widespread amongst South African (SA) children, yet data on risk factors and psychiatric consequences are limited and mixed. METHODS: Traumatised children and adolescents referred to our Youth Stress Clinic were interviewed to obtain demographic, sexual abuse, lifetime trauma and psychiatric histories. RESULTS: Data for 94 participants (59 female, 35 male; mean age 14.25 [8.25-19] years) exposed to at least one lifetime trauma were analysed. Sexual abuse was reported in 53% of participants (42.56% females, 10.63% males) with 64% of violations committed by perpetrators known to them. Multinomial logistic regression analysis revealed female gender (P=0.002) and single-parent families (P=0.01) to be significant predictors of CSA (62.5%). CSA did not predict exposure to other traumas. Sexually abused children had significantly higher physical and emotional abuse subscale scores and total CTQ scores than non-abused children. Depression (33%, X(2)=10.89, P=0.001) and PTSD (63.8%, X(2)=4.79, P=0.034) were the most prevalent psychological consequences of trauma and both were significantly associated with CSA. CONCLUSIONS: High rates of CSA predicted high rates of PTSD in this traumatised sample. Associations we found appear consistent with international studies of CSA and, should be used to focus future social awareness, prevention and treatment strategies in developing countries.  相似文献   
72.
OBJECTIVES: To test if a method for real-time detection of epileptic seizures based on electroencephalographic (EEG) analysis with simulated neuronal cell models can be modified to identify pre-seizure changes. METHODS: Our EEG analysis method consists of two simulated leaky integrate and fire units (LIFU) connected to a signal preprocessing stage that marks parts of the EEG signals with slopes larger than a preset threshold Hth with unit pulses. The LIFUs change their spiking frequency depending on the rate and the synchrony of the impinging pulse trains. Here, we use our method in a high-sensitivity mode by setting Hth to low values, which causes the LIFUs to continuously spike during the interictal state. We test if the LIFUs spiking rates change before seizure onset. RESULTS: We used 9 long-term EEGs (16+/-7 h) of 7 patients with drug resistant epilepsy. Fifteen seizures were analyzed and all were preceded by an increase of the time-averaged spiking rates SR(av) of the LIFUs. We defined a function F(Sz), which quantifies the changes of SR(av). F(Sz) increased and stayed above an individually set and fixed threshold 83+/-91 min (range: 4-330 min) before EEG seizure onset. Only two false alarms occurred. CONCLUSIONS: We conclude that EEG analysis with simulated neuronal cell models may be used to detect pre-seizure changes with high sensitivity and specificity.  相似文献   
73.
74.

Purpose

To perform Preimplantation Genetic Diagnosis (PGD) on a paternal Brca2 unknown mutation carrier with early-onset breast cancer, whose paternal grandmother and mother had breast cancer at 60s.

Method

Elucidating the linkage via single sperm haplotyping on patient''s carrier brother, and identifying the genomic deletion via BLAST followed by PCR screening. PGD was subsequently conducted.

Result

The mutant allele was found by using 4 microsatellite and 2 intragenic SNP markers. Recombination was detected in 8 % of sperms. BLAST was utilized to locate putative hairpin structure(s), followed by PCR screening with seven sets of primers. A novel 2,596 bp deletion containing exon 15 ~ 16 was identified. Due to the severity of phenotype and the integrity of exon 11 encoding RAD51 binding domain, and the fact that the patient''s mother also had breast cancer at her 60s, we speculate a possible coexistence of maternal breast cancer risk allele(s). Embryo biopsy was performed on day 3. Unaffected morula and blastocyst were replaced on day 5, resulting in a singleton livebirth. A breast lump appeared in the patient after delivery without the presence of malignant cells.

Conclusion

Concerning the assisted reproductive option for breast cancer patients, the possibility of coexistence of multiple familial risk alleles and the significance of each mutation to the phenotype should be evaluated. To eliminate misdiagnosis resulting from recombination and/or allelic drop-out, both direct mutation detection and linkage analysis approaches may be necessary. BLAST is a very useful and cost-effective tool for identifying large genomic deletion.  相似文献   
75.
76.
Following the total removal of luteal tissue, circulating plasma progesterone, intrauterine pressure, oxytocin response, and clinical progress in abortion were determined sequentially in 12 first-trimester pregnant patients. 3 patients were ovariectomized for the removal of ovarian cysts and 9 were luteectomized during tubal ligation in an attempt to terminate pregnancy in spontaneous abortion. 7 patients had corpora lutea which averaged 21 plus or minus 1mm in diameter at operation when performed at Day 49 plus or minus 2 (mean S.E.) of pregnancy. These patients responded to ovariectomy or luteectomy by a continuing decrease in progesterone, evolution in intrauterine pressure, oxytocin response, progress in cervical dilitation and, abortion. Abortion occurred with a mean lapse time of 5 plus or minus 1 days after operation. In contrast, 5 patients whose corpora lutea averaged only 11 plus or minus 1mm in diameter when removed at Day 61 plus or minus 4 of pregnancy showed only transient decrease in progesterone after operation. This decrease was followed by an increase in progesterone; no progress in the evolution of intrauterine pressure, oxytocin response, cervical dilatation, and abortion. It appears that so long as the corpus luteum serves as the major source of progesterone, it is indispensable in the maintenance of pregnancy in human subjects as it is in the clinical model animal, the rabbit. However, with the shift of progesterone production from the corpus luteum to the placenta (the luteoplacental shift) the human corpus luteum becomes dispensable. These findings identify the corpus luteum and its secretory product, progesterone, as feasible targets of fertility control strategy.  相似文献   
77.
78.
The disposition of continuous infusion alfentanil was evaluated in 13 mechanically ventilated neonates (gestational age 37.6 +/- 2.4 wks) with hyaline membrane disease (n = 7) or persistent pulmonary hypertension of the newborn (n = 6). Alfentanil was administered as a loading dose 8 micrograms/kg, followed by a variable-rate continuous infusion (maximum 10 micrograms/kg/hr; minimum 2.5 micrograms/kg/hr) for 27 hours. Serial plasma samples were obtained for pharmacokinetic analysis. Noncompartmental pharmacokinetic analysis of the data revealed the following estimates (mean +/- SD): total-body clearance 3.24 +/- 2.23 ml/kg/minute, volume of distribution 0.54 +/- 0.21 L/kg, and elimination half-life 4.14 +/- 2.58 hours. A significant effect of alfentanil plasma concentration on total-body clearance was found (r = -0.75; p = 0.02), suggesting nonlinear pharmacokinetics. No correlation was seen between total-body clearance and alfentanil dose (r = -0.37; p = 0.32). The results suggest that a larger dose-proportionality study is required to determine the linearity or nonlinearity of alfentanil pharmacokinetics in neonates.  相似文献   
79.
80.
Malaria in travelers in Rhode Island: a review of 26 cases.   总被引:1,自引:0,他引:1  
PURPOSE: We reviewed our experience with malaria in two community hospitals in Rhode Island from 1986 to 1990. RESULTS: Twenty-six patients with malaria were identified. Fifteen patients were immigrants who had acquired malaria while visiting their country of origin, particularly West Africa. Fever was present in 67% of cases and gastrointestinal complaints were prominent in 26%. Individuals with a past history of malaria could accurately distinguish current malarial infections from other febrile illnesses. Two patients developed cerebral malaria. Plasmodium falciparum was identified in 77% of the cases. CONCLUSIONS: Malaria is an important diagnosis that United States physicians must consider in the medical evaluation of returning travelers. A significant increase in the number of cases of P. falciparum acquired in East Africa has been reported in recent years. P. falciparum infection must be rapidly diagnosed and treated since delays may result in complications of malaria that may lead to death. Mefloquine is currently recommended by the Centers for Disease Control for prevention of malaria in travelers visiting countries endemic for chloroquine-resistant malaria. This change may alter the epidemiology of malaria in the United States in the future.  相似文献   
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