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991.
The timing of surgery for velopharyngeal dysfunction has been based on assumptions about the relation between age, speech development, and velopharyngeal dysfunction. Cleft palate teams often counsel parents to have an intervention for velopharyngeal dysfunction performed earlier rather than later, believing that earlier interventions result in more rapid or better normalization of speech. The objective of this retrospective chart review study is to determine whether the age at surgical intervention for velopharyngeal dysfunction has an effect on the subsequent length of speech therapy. Of 174 patients included in the study database, 36 had velopharyngeal dysfunction for which further velopharyngeal management was required. Of the 36 patients who received surgical velopharyngeal dysfunction management, 27 had verifiable speech therapy records. These 27 patients represent the study population. The outcome measure was the total length of subsequent speech therapy until speech normalization. The data suggest that there is no relation between the age at velopharyngeal dysfunction surgical management and the amount of speech therapy needed to achieve normalization of the speech impairments secondary to velopharyngeal dysfunction after that management. In conclusion, 1) the age at surgical velopharyngeal dysfunction management (pharyngeal flap or sphincter pharyngoplasty) does not have an effect on subsequent normalization of speech as measured by the duration of speech therapy necessary to achieve normalization of the speech impairments secondary to velopharyngeal dysfunction after that management, and 2) the age at surgical velopharyngeal dysfunction management does not affect the likelihood of subsequent surgical velopharyngeal dysfunction management procedures.  相似文献   
992.
The purpose of this study was to survey the prevalence of streptococcal species, especially Streptococcus anginosus (which has been reported to be associated with cancer in the upper digestive tract), Streptococcus constellatus, and Streptococcus intermedius in the saliva of different age groups. A sequence analysis of 16S rDNA was performed and DNA quantified using real-time polymerase chain reaction. The S. anginosus level increased with age, whereas the levels of S. constellatus and S. intermedius did not change. Streptococcus mitis was the predominant species in the saliva of all the age groups but, unlike the S. anginosus, the proportion of S. mitis in the salivary bacteria decreased with age. The increase in S. anginosus with age should be carefully monitored because of its association with diseases, including cancer.  相似文献   
993.
Loss of maxillary substance following trauma varies significantly in relation to the dimensions, site and type of tissue involved. Anatomical maxillary interruptions, loss of dental elements and consequent bone re-absorption give rise to altered chewing, swallowing and speech functions. Treatment of pathological conditions over the years has seen the development of surgical protocols designed to achieve simultaneous aesthetic and functional restoration of the stomatognatic apparatus. The advent of osteointegrated implantology and continual progress in pre-prosthesis surgical techniques have undoubtedly revolutionised established approaches to prosthetic rehabilitation by introducing the concept of supported implant prostheses. The implantation protocols used are a safe and reproducible treatment method suitable for adequate anchorage of such prosthetic implants; the application of such protocols in any case is subordinated to the presence of adequate morpho-volumetric bone at the skeletal bases. Depending on the entity of maxillary loss of substance, the reconstruction methods we propose, in agreement with numerous other authors, are based on the use of free and free-revascularised autologous bone grafts or, even more recently, the application of osteogenetic distraction techniques. The purpose of this article is to evaluate treatment of loss of maxillary substance following trauma by means of non-revascularised free flaps. The use of free grafts of autologous bone is elective in patients presenting bone deficits less than 6 cm with and/or without upkeep of maxillary and mandibular cortical bone continuity but without compromise to the integrity and trophism of the soft tissues.  相似文献   
994.
This study compared SYBR Green real-time quantitative PCR (qPCR) with standard plate counting for the enumeration of Streptococcus mutans in oral samples. Oral samples (n = 710) were collected from high-caries-risk children for quantification of S. mutans by qPCR using primer pairs. The S. mutans copy number was calculated with reference to a qPCR quantification cycle (Cq) standard curve and compared with the absorbance value at 600 nm of a standard suspension of S. mutans UA159. The S. mutans copy number results were evaluated in relation to standard plate count (SPC) results obtained from each sample following culture on Petri plates containing S. mutans selective media and reported as colony-forming units (CFUs). The mean S. mutans copy number calculated from qPCR was higher than the SPC CFUs (1.3 × 10(6) and 1.5 × 10(5) CFUs, respectively). The qPCR values were usually higher in individual samples and qPCR detected the presence of S. mutans 84% (231/276) of the time that the SPC did not, compared with 33% (4/12) of the time when qPCR failed to detect S. mutans and the SPC did. The qPCR technique was found to be more sensitive for detection of S. mutans from oral samples, a method that is not dependent on the viability of the sample taken and therefore is proposed as a more reliable and efficient means of quantification of S. mutans.  相似文献   
995.

Aim

Mouth rinses containing enzymes are designed for patients suffering from xerostomia. The objective of the present in situ study was to investigate the efficacy of these rinses for targeted accumulation and immobilisation of protective enzymes in the acquired pellicle.

Methods

A number of six healthy subjects carried bovine enamel slabs fixed on individual upper jaw splints for pellicle formation in situ. After 1 min, they rinsed with biotène or BioXtra for 10 min, respectively. Enzyme activities of lysozyme, peroxidase and glucoseoxidase in the in situ pellicle and in the saliva were assayed before as well as 0, 20 and 40 min after the rinses. The assays for the respective enzyme activities were based on fluorogenic substrates. Separate experiments were performed for the different enzymes and mouth rinses, respectively. Statistical evaluation was carried out with the Kruskal-Wallis test.

Results

None of the investigated rinses had any significant impact on the activities of lysozyme, peroxidase and glucoseoxidase detectable in the in situ pellicle or in the saliva (Kruskal-Wallis test, p > 0.05). Despite the fact that both products should contain lactoperoxidase activity according to manufacturers’ instructions, no peroxidase activity was measurable in the pure mouth rinses.

Conclusion

With the tested enzymatic mouth rinses targeted accumulation and immobilisation of protective enzymes in the in situ pellicle did not seem possible.  相似文献   
996.
A hallmark of infection with the gram‐negative pathogen Porphyromonas gingivalis is the induction of a chronic inflammatory response. P. gingivalis induces a local chronic inflammatory response that results in oral inflammatory bone destruction, which manifests as periodontal disease. In addition to chronic inflammation at the initial site of infection, mounting evidence has accumulated supporting a role for P. gingivalis‐mediated periodontal disease as a risk factor for several systemic diseases including, diabetes, preterm birth, stroke, and atherosclerotic cardiovascular disease. A growing number of in vitro studies have demonstrated that P. gingivalis infection stimulates cell activation commensurate with expected responses paralleling inflammatory atherosclerotic‐type responses. Furthermore, various mouse models have been used to examine the ability of P. gingivalis to stimulate chronic inflammatory plaque accumulation and recent studies have pointed to a pivotal role for innate immune signaling via the Toll‐like receptors in the chronic inflammation associated with P. gingivalis infection. In this review we discuss the pathogen and host cell specificity of these responses and discuss possible mechanisms by which this oral pathogen can induce and maintain a chronic state of inflammation at sites distant from oral infection.  相似文献   
997.
This study presents a new method for objective assessment of the distraction regenerate using three-dimensional quantitative computer tomography (3D-QCT). The distraction specimens of 16 sheep that underwent bifocal cranial distraction osteogenesis to reconstruct a critical size defect were used to evaluate this method. To analyse the validity of this method the results were compared to conventional quantitative computer tomography (QCT). Squared correlation coefficients (r(2)) according to Sackett showed a high reliability (r(2) > 70% for the total DO regenerate, DO Regions 2-4). Method comparison according to Bland-Altman (< or =6.25% of measurements out of 95% limits of agreement) showed that three-dimensional computer tomography based bone densitometry is valid for future DO research.  相似文献   
998.
Subantral sinus augmentation is often necessary to permit placement of endosseous implants. Recent efforts to improve wound healing have focused on autogenous sources of bioactive mediators, such as platelet-rich plasma (PRP), which offer the potential to enhance the biological activity of bone replacement grafts. The purpose of this randomized, single-blinded, controlled study was to compare bone formation after subantral maxillary sinus augmentation with freeze-dried bone allograft (FDBA) plus PRP versus FDBA plus resorbable membrane. Ten patients underwent bilateral maxillary subantral sinus augmentation, with sites within subjects randomized to receive FDBA plus PRP or FDBA plus membrane. Core biopsy specimens were obtained 4.5 to 6 months after the grafting procedure at time of implant placement. Histomorphometric analysis revealed a significantly higher percentage of vital tissue in sinuses after treatment with FDBA and PRP (78.8 +/- 8.3) than with FDBA and membrane (63.0 +/- 15.7). Moreover, the percentage of bone formation in sinuses augmented with the combination of FDBA plus PRP (33.3 +/- 11.3) was nonsignificantly (P 相似文献   
999.
This study was aimed at comparing the cultivable microorganisms in canals with periapical radiolucencies with exposed and unexposed pulp space. Microbiological samples were taken and analyzed from 45 canals with exposed pulp space, and 43 canals with unexposed pulp space. The canal contents were analyzed by aerobic/anaerobic culture, and conventional identification techniques. There were 211 isolates of bacteria belonging to 28 genera and 55 species recovered from exposed canals. In the unexposed group, 185 isolates of bacteria were recovered, of which 54 species of 28 genera were identified. Among the four most common genera, Prevotella was significantly more common in the exposed group (51/211 in the exposed group versus 30/185 in the unexposed group) (p = 0.049), while there were no differences in prevalence of Actinomyces, Peptostreptococcus, and Campylobacter between two groups of canals. In addition, Fusobacterium nucleatum and Propionibacterium acne were significantly more common in the unexposed canals (p = 0.047 and p = 0.0051, respectively). Similarity in bacterial species in these two groups suggests that pulp space exposure may not be a significant factor in determining the type of bacteria present in infected canals.  相似文献   
1000.
By the formation of cyclic guanosine 3',5'-monophosphate (cGMP), nitric oxide (NO)-sensitive enzyme-soluble guanylate cyclase (sGC) plays a receptor role for NO within the NO-cGMP signaling cascade, which is involved in vasodilatation and neurotransmission. The hypothesis that NO-cGMP signaling molecules modulate cells of the dentin-pulp complex was investigated in rat molars by histochemical, immunohistochemical, immuno-ultrastructural, and organ bath techniques. NO synthase (NOS) I-III, the sGC alpha(2)-subunit/beta(1)-subunit, and cGMP were detected in odontoblasts and blood vessels. NOS I, sGC alpha(2), and cGMP were identified in nerve fibers. Treatment of rat molars with the NO donor NONOate (10(-5) M) increased cGMP staining intensities in blood vessels and odontoblasts, while NO synthase inhibitor L-NAME (10(-4) M) attenuated intensity of the reaction products for cGMP, suggesting an effect of endogenous NO on sGC. These correlations of patterns and alterations of cGMP staining intensities after treatment with the NO donor or NO inhibitor might represent an NO-sGC-cGMP signaling-dependent modulation of odontoblasts, blood vessels, and nerve fibers in the dentin-pulp complex.  相似文献   
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