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61.
Despite some serious past efforts to clarify its multiple dimensions and meanings, access to health care has remained a rather elusive concept, hampering the work of health care policymakers and professionals as they endeavor to effect meaningful health care reform. This article provides perhaps the most detailed clarification of the access concept, especially the crucial linkages among the various access dimensions, and presents a comprehensive conceptual framework for evaluation and planning activities as they relate to people's access to health care services. The proposed conceptual model recognizes access as the outcome of a process involving the interplay between the characteristics of the health care service system and of potential users in a specified area, and moderated by health care related public policy and planning efforts. An elaborate typology of access, incorporating four pairs of access dimensions, is also derived. This atomization of the concept allows us to focus on specific aspects of the access to health care problem, and to develop precise outcome indicators of health system performance for evaluative purposes. Further, it enables the access concept and its pertinent dimensions to be put into proper perspective when assessing the health care access situation in a specific national or regional context. The relevance of the proposed access model and the typology to health care planning in general, and to spatial planning of health care service systems in particular, is also discussed.  相似文献   
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In 1992 at Vivekanand Hospital in Latur, Maharashtra State, India, researchers randomly allocated 326 pregnant women, 15-45 years old, at full term, to either the modified squatting position group (study group) or the normal lithotomy delivery position group (control group) to determine whether the modified squatting position using a birth cushion has any advantages over the normal delivery position. The U-shaped cushion is inexpensive, constructed with coir and foam, and has a washable cover. Its two handles provide the woman support as she pushes and delivers the newborn. There were 145 women in the study group and 181 in the control group. Women in the squatting position did not receive any episiotomies. They spent less time pushing (i.e., in second stage of labor) than those in the control group (median, 21.2 vs. 39.32 min; p 0.01), especially among gravidae 2 and above. The time required to perform vaginal operative delivery was much shorter for the squatting position than for the normal delivery position (11.6 vs. 28.86 min; p 0.01). Fetal stress was more common among newborns delivered by the normal delivery position than among those delivered by the squatting position (7.73% vs. 3.44%; p 0.05). Women in the squatting group were more likely to have an intact perineum after delivery than those in the control group. None of the women in the control group had postpartum vulval edema, while five in the study group did. The edema was mild, however, and resolved itself within 24 hours of delivery. Most women in the squatting position group were satisfied with this position. These findings suggest that the squatting position using a birth cushion has more benefits than the normal delivery position. It allows better coordination and more effective pushing. Traditional birth attendants and female health workers at subcenter and primary health center levels can be trained to use the birth cushion during labor.  相似文献   
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Although abnormal collagen metabolism has been ascribed an important role in the high recurrence rates after surgical hernia repair, knowledge on tissue sampled in the region affected by inguinal hernias is poor. In the present study, we determined collagen type I and type III in the skin of adult patients with indirect and direct inguinal hernias by both immunohistochemistry and Western blot analysis. In addition, we quantified the immunohistochemical expression of fibronectin and matrix metalloproteinase (MMP)-1 and -13. The results indicated that the ratio of collagen type I/III was significantly decreased in the skin of patients with either indirect (n = 9) or direct hernia (n = 7), with a concomitant increase in collagen type III (p < 0.001 vs. controls, n = 7, without affection of the inguinal region). There was no significant difference between patients with indirect and direct hernia (p > 0.05). MMP-13 was not expressed in any of the skin samples investigated, whereas MMP-1 was found in the epidermis. Fibronectin was predominantly detected at the epidermal-dermal junction. MMP-1, MMP-13 and fibronectin levels were significantly different between patients and controls (p > 0. 05). We conclude that in contrast to the unchanged expression of fibronectin and MMP-1 and MMP-13, the decreased ratios of collagen tpye I/III with the basically increased amount of collagen type III could be of significant importance for the pathophysiology of hernias. The specific ratio collagen I/III probably reflects the altered structural integrity and mechanical stability of the connective tissue in both indirect and direct hernias. Moreover, our findings stress that hernias should be regarded as the manifestation of a systemic disease in the inguinal region with a genetic background, explaining the high recurrence rates after repeated suture repair, as well as the usefulness of surgical meshes in this clinical setting.  相似文献   
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Purpose. The objective of this work was to develop and validate blood sampling schemes for accurate AUC determination from a few samples (sparse sampling). This will enable AUC determination directly in toxicology studies, without the need to utilize a large number of animals. Methods. Sparse sampling schemes were developed using plasma concentration-time (Cp-t) data in rats from toxicokinetic (TK) studies with the antiepileptic felbamate (F) and the antihistamine loratadine (L); Cp-t data at 13–16 time-points (N = 4 or 5 rats/time-point) were available for F, L and its active circulating metabolite descarboethoxyloratadine (DCL). AUCs were determined using the full profile and from 5 investigator designated time-points termed critical time-points. Using the bootstrap (re-sampling) technique, 1000 AUCs were computed by sampling (N = 2 rats/point, with replacement) from the 4 or 5 rats at each critical point. The data were subsequently modeled using PCNONLIN, and the parameters (ka, ke, and Vd) were perturbed by different degrees to simulate pharmacokinetic (PK) changes that may occur during a toxicology study due to enzyme induction/inhibition, etc. Finally, Monte Carlo simulations were performed with random noise (10 to 40%) applied to Cp-t and/or PK parameters to examine its impact on AUCs from sparse sampling. Results. The 5 time-points with 2 rats/point accurately and precisely estimated the AUC for F, L and DCL; the deviation from the full profile was ~10%, with a precision (%CV) of ~15%. Further, altered kinetics and random noise had minimal impact on AUCs from sparse sampling. Conclusions. Sparse sampling can accurately estimate AUCs and can be implemented in rodent toxicology studies to significantly reduce the number of animals for TK evaluations. The same principle is applicable to sparse sampling designs in other species used in safety assessments.  相似文献   
67.
We report a case of Crohn's disease with involvement of the foreskin in a 12-year-old boy. One year previously, on the basis of clinical features (diarrhea with blood, perianal fissures) and histologic examination, a diagnosis of Crohn's disease was made. Subsequently, he developed phimosis and balanitis and underwent circumcision. Sections submitted from the foreskin revealed noncaseating granulomatous inflammation consistent with Crohn's disease. Crohn's disease with involvement of the genitalia is unusual. Only 26 cases including our case have been reported in the scientific literature. We have analyzed these cases with emphasis on gender, age, clinical features, duration of Crohn's disease, and probable mode of spread to the genitalia. Careful examination of sections from genital lesions, including those submitted from the foreskin, is essential to detect small isolated granulomas that may then lead to the diagnosis of inflammatory bowel disease.  相似文献   
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The series of vasicine (1) analogues, an alkaloid from Adhatoda vasica Nees., were synthesized with changes in A, B or C rings. Compounds 13-19 were evaluated for in vitro bronchodilatory activity using isolated guinea pig tracheal chain. Compounds 3-8 were also synthesized in good yields using microwave-mediated synthesis under solvent free conditions. Compounds 5 and 8 with seven-member C ring were more active than etofylline and caused 100% relaxation of both the histamine and acetycholine pre-contracted guinea pig tracheal chain. The structure-activity relationship studies showed that the quinazoline and oxo functionalities were essential for activity. The compounds without C ring and instead having aliphatic and phenyl substitutions in B ring showed relaxation against histamine pre-contracted tracheal chain only, 2-methyl substituted analogues, 12 and 13, being most active with 100% relaxation effect.  相似文献   
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