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71.
Nurse-midwifery students face multiple stressors in their educational experience. Strategies to resolve stress and promote adaptation to the new role are examined and measures used to promote students' adaptation to the educational experience are described.  相似文献   
72.
73.
The low frequency but highly intense disruptive behavior of 10 institutionalized mentally retarded persons was treated by providing them with opportunities for vigorous exercise. In two experiments, severely aggressive and hyperactive clients were exposed to two daily periods of jogging and strenuous activities in multiple baseline designs across clients. Rating scale data collected daily from cottage and school personnel indicated a systematic reduction in problem behavior for 8 of the 10 participants to levels considered "not a problem" or only "an occasional problem." Physical exercise may offer promise as an effective, benign, and practical adjunct to other treatment and management techniques.  相似文献   
74.
The genetic basis for addiction to tobacco smoking--particularly that of the perception of olfactory stimuli that may be important in reinforcing smoking addiction--is largely unknown. A cluster of genes for olfactory receptors is in close proximity to the MHC region on chromosome 6. Polymorphisms of MHC class III genes (RCCX modules, TNFA promoter polymorphisms) were determined in 101 healthy subjects and 232 coronary artery disease (CAD) patients from Hungary with defined tobacco smoking habits. A highly significant association between ever smoking (past + current smokers) and a specific MHC haplotype was observed (odds ratios = 2.14-4.13; P-values = 0.012 to <0.001). This haplotype is characterized by the presence of C4A null alleles and a solitary short C4B gene linked to the TNF2 allele of the promoter for TNFA gene. This haplotype occurred more frequently in the ever smokers than in the never smokers [odds ratio: 4.97 (1.96-12.62); P = 0.001], and such associations were stronger in women (odds ratio = 13.6) than in men (odds ratio = 2.79). An independent study of complement C4 protein polymorphism and smoking habits in Icelandic subjects (n = 351) yielded similar and confirmative results. Considering the documented link between olfactory stimuli and smoking in females, and the presence of a cluster of odorant receptor genes close to the MHC class I region, our findings implicate a potential role of the MHC-linked olfactory receptor genes in the initiation of smoking.  相似文献   
75.
Forty-nine primary retinoblastoma (Rb) tumors were analyzed by the use of comparative genomic hybridization (CGH), and clinical/histological correlations were performed. Adverse histological factors were present in 13 patients. Chromosomal imbalance was a frequent phenomenon, seen in 96% of the tumors. Gain of 6p represented the most frequent event (69% of the tumors), whereas +1q was observed in 57%, confirming that these abnormalities are key secondary events in retinoblastoma tumor progression. Loss of 13q and 16 was significantly associated with tumors displaying adverse histo-prognostic factors, whereas -16q was significantly associated with tumors without adverse features. In three patients who developed an extra-ocular relapse, the tumors showed -13q and 2/3 had -5q, suggesting that these abnormalities may be associated with metastasis. Children >or= 36 months of age at enucleation tended to have more CGH abnormalities per tumor than children < 12 months (median numbers 11 vs. 3). In addition, +1q, +13q, -16, and -16q were more frequent in children with an older age at enucleation. Identical CGH changes were found in both tumors from one patient with bilateral tumors, suggesting a common origin. It is possible that tumors displaying loss of 13q and 5q indicate those patients who may suffer an adverse outcome and who would require alternative or more intensive therapy. CGH analysis on larger cohorts and in prospective clinical trials will be invaluable in determining whether a genetic classification of retinoblastoma represents a reliable measure of prognosis.  相似文献   
76.
Perhaps the most dramatic position of a newborn after delivery is when there is hyperextension of the neck and spine. It will have been presented in utero and today, almost always, such babies will have been delivered by C‐section. The associated anomalies are variable. The process(es) that can lead to cervical hyperextension is/are largely unknown. The outcome is variable from lethal to completely resolve. Individuals with arthrogryposis and in particular with Amyoplasia appear to have an increased frequency of neck, cervical, and spine hyperextension at birth. We present here 41 cases of arthrogryposis (mainly Amyoplasia) with fetal cervical hyperextension. The outlook is surprisingly good if spinal cord trauma does not occur. Ultrasound late in pregnancy when arthrogryposis is recognized prenatally should determine whether cervical hyperextension has developed, so that appropriate preventive measures can be taken.  相似文献   
77.
Changes in extracellular pH (pHo) induce changes in the intracellular pH (pHi) of cardiac myocytes that are slow and attenuated. Little however is known about the effects of changing pHo on the pHi of the coronary smooth muscle cells. We have therefore directly compared the effects of altering pHo on pHi of both coronary and cardiac myocytes. Carboxy-SNARF was used in single cells to measure pHi. Alteration of pHo caused corresponding changes in pHi that were large (70–80 % of pHo) and rapid in coronary myocytes compared to cardiac myocytes. In contrast, changes of pHi produced by weak acids or bases produced similar pHi responses in both types of cells. It is suggested that the differential effects of pHo on coronary and cardiac cells may be functionally significant, as it will allow rapid alteration of coronary perfusion to meet tissue needs, while maintaining cardiac output.Supported by the BHF and MRC  相似文献   
78.
Chondromyxoid fibroma is a rare benign cartilaginous bone tumour characterized by morphological features that resemble different steps of chondrogenesis in terms of both cellular morphology, ranging from spindled to rounded cells, and the extracellular matrix formed, which ranges from fibrous to cartilaginous. The presence in chondromyxoid fibroma of signalling molecules that regulate the spatial expression of proteins involved in normal cartilage proliferation and differentiation was investigated in samples from 20 patients and compared with articular chondrocytes from 11 normal donors cultivated in 3D pellet culture. Sections were stained with safranin-O and H&E, and immunohistochemistry was performed for p16, cyclin D1, FGFR3, BCL2, p21, PTHLH, PTHR1 and N-cadherin. Expression patterns were analysed using hierarchical clustering. In chondromyxoid fibroma, specific morphological features correlated with a distinct pattern of expression. Comparison with normal chondrocytes in pellet culture showed a striking morphological resemblance, but with an unmistakably different pattern of expression. N-cadherin, PTHLH, and PTHR1 were expressed to a significantly higher level (p < 0.01) in articular chondrocyte pellets but, conversely, there was significantly lower expression of cyclin D1, p16 and BCL2 (p < 0.05) in these cells. Morphological similarities reflect common steps in cartilage differentiation, albeit driven by different molecular mechanisms. The proteins we have found to be differentially expressed seem crucial for neoplastic chondrogenesis.  相似文献   
79.
This article describes the Women Recovering from Abuse Program (WRAP), an outpatient day-hospital program for women suffering from the sequelae of childhood abuse. WRAP was conceived in 1998 by clinicians who advocated for its development based on a growing need to provide women who had experienced childhood trauma an alternative to an inpatient program. WRAP draws from a Stage 1 treatment approach to address chronic interpersonal trauma and dissociation by incorporating psychopharmacology, individual and group psychotherapy. The program is structured into two phases: a preparatory Building Resources Group (BRG) and an intensive multimodal segment comprised of seven types of group therapy. Each group is described in terms of the treatment rationale and its structure and process. Two research studies to date support the effectiveness of WRAP.  相似文献   
80.
Longitudinal data were used to investigate whether anxiety, depressive, disruptive, personality, or substance use disorders are associated with risk for the development of eating disorders during adolescence or early adulthood. Psychiatric disorders were assessed among 726 youths from a random community sample during adolescence and early adulthood. Depressive disorders during early adolescence were associated with elevated risk for the onset of eating disorders, dietary restriction, purging behavior, and recurrent weight fluctuations after preexisting eating problems and other psychiatric disorders were controlled statistically. Disruptive and personality disorders were independently associated with elevated risk for specific eating or weight problems. The present findings suggest that depressive disorders during early adolescence may contribute to the development of eating disorders during middle adolescence or early adulthood.  相似文献   
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