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101.
Oral vaccines for polio (OPV) and rotavirus are less effective in children in the developing world. The reasons for this are not well understood. We tested for risk factors for poor response to OPV in infants from an urban slum of Dhaka, Bangladesh. Diminished serum neutralizing response to OPV, but not failure of intramuscularly administered vaccines, was associated with malnutrition, diarrhea, and shorter breastfeeding duration. Children with malnutrition (WAZ <−2) had significantly lower OPV 3 titers (p = 0.029). Children who had 2 or more diarrhea episodes during the 1st months of life were more than twice as likely to experience OPV failure as those who had 1 diarrhea episode or no diarrhea (p = 0.0245). In contrast, each additional month in exclusive breastfeeding was associated with an increase in OPV 3 titer by 0.41 (p = 0.0072) and 0.16 (p = 0.0065) at the 25th and 50th percentiles of OPV 3 titers respectively. These data are consistent with a defect in induction of immunity in the gut for OPV but not parenteral vaccines, a defect that may be amenable to intervention in part via promotion of exclusive breastfeeding.  相似文献   
102.
103.

Objective

In developing countries like Bangladesh, delayed presentation for disorders of sex development (DSD) is common, and provides some special problems for management. There remains significant controversy about appropriate sex assignment in this group. We aimed, therefore, to assess gender identity (GI) in 50 consecutive patients with DSD presenting to a referral centre in Chittagong, Bangladesh, and correlate it with Prader score, to see if the latter could be used to predict GI.

Methods

A cross-sectional, case–control study of 50 consecutive children with DSD and 50 children with vascular anomalies was conducted in the Pediatric Surgical Clinic, Chittagong Medical College and Hospital. After informed consent, patients and controls provided oral answers to a GI questionnaire and had a detailed history and physical examination. Sex-typed activities were assessed by observations of a structured toy play and the child’s selection of a toy to keep. Both patients and parents then completed the Child Game Participation Questionnaire.

Results

There were no differences in age (2–16 years, mean 8.74) between controls and DSD patients (11 46, XX DSD, 32 46, XY DSD, 4 MGD, 3 ovo-testicular DSD). Fifteen of the DSD patients (30 %) came from consanguineous marriages and only 2 of the control patients had consanguinity of their parents. For the 13-question GI interview, there was no overall difference between DSD cases and controls. For the 46, XX DSD subgroup, there was a significantly higher score (11.1 ± 7.1) compared with control girls (4.5 ± 4.7) (p < 0.05), while for DSD and control boys, there was a positive correlation with age and GI (p < 0.01). Prader score correlated with GI score in both control (r = 0.91) and DSD patients (r = 0.75) (p < 0.01), DSD girls played significantly less with girls’ toys than controls (p < 0.01), but there was no differences for the boys. Composite scores on GI and gender-related behaviour correlated with Prader score for DSD patients (r = 0.61) (p < 0.01).

Conclusion

This study supports the view that GI and gender-role behaviour should be assessed routinely in DSD patients presenting after the neonatal period, so that sex assignment is in accordance with behaviour. Prader scores showed a good correlation with GI and gender role behaviour.  相似文献   
104.
105.
Objective. To investigate allelic variations of T cell receptor residues for a contribution to rheumatoid arthritis (RA) susceptibility. Methods. We conducted an RA case-control study involving 1,579 northwest Europeans: 766 patients with erosive and rheumatoid factor-positive disease and 813 control subjects. Productive changes of segments TCRAV6S1, TCRAV7S1, TCRAV8S1, TCRAV10S2, and TCRBV6S1, TCRBV6S7 were investigated by single-strand conformation polymorphisms. The TCRAV8S1 association was confirmed by restriction fragment length polymorphism. Results. In the systematic study (77 patients and 119 controls), an increase in 1 TCRAV8S1 genotype was found in the RA patients (P = 0.0004). This finding was replicated in 2 further populations, one from France (212 patients and 254 controls) and the other from Britain (477 patients and 440 controls), with a similar odds ratio (OR), which allowed pooling of the data and confirmation of the association (OR 1.3 [95% confidence interval 1.1-1.7], P = 0.008). Conclusion. These findings show evidence that TCRA is an RA susceptibility locus.  相似文献   
106.
Objective. To determine if abnormal collagen metabolism is a characteristic of fibromyalgia. Methods. The diagnosis of fibromyalgia was made according to the American College of Rheumatology criteria. Skin biopsy samples were obtained from the trapezius region of 8 patients with fibromyalgia. Urine was collected under standardized conditions from 55 control subjects and 39 patients with fibromyalgia, and serum was obtained from 17 controls and 22 patients with fibromyalgia. Pyridinoline (Pyd), an indicator of connective tissue disease, and deoxypyridinoline (Dpyd), an indicator of bone degradation, both of which represent products of lysyl oxidase-mediated crosslinking in collagen, were analyzed by ion-paired and gradient high-performance liquid chromatography (HPLC) methods with fluorescence detection. Levels of hydroxyproline (Hyp), a collagen turnover marker, were also measured. The findings were related to creatinine levels, and the Pyd:Dpyd ratio was determined. Results. Highly ordered cuffs of collagen were observed around the terminal nerve fibers by electron microscopic examination of biopsy tissue from all 8 patients with fibromyalgia, but were not observed in any of the control skin samples. The Pyd:Dpyd ratios in the urine and serum and the Hyp levels in the urine were significantly lower in patients with fibromyalgia than in healthy controls. Conclusion. Decreased levels of collagen cross-linking in fibromyalgia may contribute to remodeling of the extracellular matrix and collagen deposition around the nerve fibers, and may contribute to the lower pain threshold at the tender points. Analysis of altered collagen metabolism either by histologic examination on biopsy, or preferably, by HPLC analysis of collagen metabolites in urine or serum may aid in understanding more about the pathogenesis of fibromyalgia.  相似文献   
107.
Objective. Neuromuscular joint protection requires proprioceptive input and motor output. Impairment of proprioception in knee osteoarthritis (OA) may contribute to, and/or result from, the disease. If this impairment was exclusively a local result of OA, a between-knee difference would be expected in patients with unilateral OA (UOA). To explore causal directions, 2 hypotheses were tested: 1) proprioception is worse in UOA patients versus elderly controls; 2) proprioception is worse in the arthritic knee versus the unaffected knee in UOA patients. Methods. Twenty-eight UOA patients (Kellgren-Lawrence grade ⩾2 in 1 knee and <2 in the other knee) and 29 elderly controls were enrolled. The unaffected knee of each UOA patient and both knees of the elderly controls were required to meet symptom, examination, and radiographic criteria. Proprioception (detection threshold of joint displacement after slow, passive, automated knee motion), body mass index, pain, functional status, range of motion, and laxity were measured. Results. UOA patients had worse proprioception than did elderly controls, in either knee. A between-knee difference was not found in UOA patients. Conclusion. Impaired proprioception is not exclusively a local result of disease in knee OA. The relative importance of impaired proprioception in the development and progression of knee OA will require longitudinal study.  相似文献   
108.
Objective. T cells treated with DNA methylation inhibitors overexpress lymphocyte function-associated antigen 1 (LFA-1), which results in autoreactivity, and the autoreactive cells cause a lupus-like disease in vivo, suggesting a mechanism by which some agents may cause drug-induced lupus. This study compared the effects of procainamide (Pca) and hydralazine (Hyd) with those of structural analogs, to determine if the degree of LFA-1 overexpression and T cell autoreactivity correlated with the ability of the agents to induce autoimmunity. Methods. Cloned murine T helper 2 cells were treated with Pca, N-acetylprocainamide, Hyd, Phthalazine, or hydroxyurea (HU). The treated cells were then compared for LFA-1 overexpression, autoreactivity, and the ability to induce autoimmunity in vivo. Results. Pca and Hyd were more potent than their analogs or HU in all 3 assays. Conclusion. The results support a relationship between LFA-1 overexpression, T cell autoreactivity, and autoimmunity, and suggest a mechanism by which Pca and Hyd, but not the analogs, may cause drug-induced lupus.  相似文献   
109.
Kidney disease is becoming a global public health issue. Acute kidney injury (AKI) and chronic kidney disease (CKD) have serious adverse health outcomes. However, there is no effective therapy to treat these diseases. Lactoferrin (LF), a multi-functional glycoprotein, is protective against various pathophysiological conditions in various disease models. LF shows protective effects against AKI and CKD. LF reduces markers related to inflammation, oxidative stress, apoptosis, and kidney fibrosis, and induces autophagy and mitochondrial biogenesis in the kidney. Although there are no clinical trials of LF to treat kidney disease, several clinical trials and studies on LF-based drug development are ongoing. In this review, we discussed the possible kidney protective mechanisms of LF, as well as the pharmacological and therapeutic advances. The evidence suggests that LF may become a potent pharmacological agent to treat kidney diseases.  相似文献   
110.
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