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1.

A key goal for implementation science is the identification of evidence-based consultation protocols and the active ingredients within these protocols that drive clinician behavior change. The current study examined clinicians’ self-coding of fidelity as a potential active ingredient of consultation for the Attachment and Biobehavioral Catch-up (ABC) intervention. It also examined two other potential predictors of clinician fidelity in response to consultation: dosage of consultation and working alliance. Twenty-nine clinicians (97% female, 62% White, M age?=?34 years) participated in a year of weekly fidelity-focused ABC consultation sessions, for which clinicians self-coded fidelity and received consultant feedback on both their coding and their fidelity. Data from the ABC fidelity measure were available for 1067 sessions coded by consultants, and clinicians’ self-coding accuracy was calculated from 1044 sessions coded by both clinicians and consultants. Alliance was measured with the Working Alliance Inventory—Trainee and Supervisor Versions. The study was observational, and fidelity and self-coding accuracy were modeled across time using hierarchical linear modeling. Clinicians’ ABC fidelity, as well as their self-coding accuracy, increased over the course of consultation. Clinicians’ self-coding accuracy predicted their initial fidelity and growth in fidelity. Working alliance was also linked to fidelity and self-coding accuracy. These results suggest that clinician self-coding should be further examined as an active ingredient of consultation. The study has important implications for the design of consultation procedures and fidelity assessments.

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Genital antibody responses were compared in female mice immunized intravaginally (i.vag.) or intranasally (i.n.) with a bacterial protein antigen (AgI/II of Streptococcus mutans) coupled to the B subunit of cholera toxin. Serum and salivary antibodies were also evaluated as measures of disseminated mucosal and systemic responses. Although i.vag. immunization induced local vaginal immunoglobulin A (IgA) and IgG antibody responses, these were not disseminated to a remote secretion, the saliva, and only modest levels of serum antibodies were generated. In contrast, i.n. immunization was substantially more effective at inducing IgA and IgG antibody responses in the genital tract and in the circulation, as well as at inducing IgA antibodies in the saliva. Moreover, mucosal and systemic antibodies induced by i.n. immunization persisted for at least 12 months. Analysis of the molecular form of genital IgA indicated that the majority of both total IgA and specific IgA antibody was polymeric, and likely derived from the common mucosal immune system.  相似文献   
4.
Colonization of the cardiovascular endothelium by viridans group streptococci can result in infective endocarditis and possibly atherosclerosis; however, the mechanisms of pathogenesis are poorly understood. We investigated the ability of selected oral streptococci to infect monolayers of human umbilical vein endothelial cells (HUVEC) in 50% human plasma and to produce cytotoxicity. Planktonic Streptococcus gordonii CH1 killed HUVEC over a 5-h period by peroxidogenesis (alpha-hemolysin) and by acidogenesis but not by production of protein exotoxins. HUVEC were protected fully by addition of supplemental buffers and bovine liver catalase to the culture medium. Streptococci were also found to invade HUVEC by an endocytic mechanism that was dependent on polymerization of actin microfilaments and on a functional cytoskeleton, as indicated by inhibition with cytochalasin D and nocodazole. Electron microscopy revealed streptococci attached to HUVEC surfaces via numerous fibrillar structures and bacteria in membrane-encased cytoplasmic vacuoles. Following invasion by S. gordonii CH1, HUVEC monolayers showed 63% cell lysis over 4 h, releasing 64% of the total intracellular bacteria into the culture medium; however, the bacteria did not multiply during this time. The ability to invade HUVEC was exhibited by selected strains of S. gordonii, S. sanguis, S. mutans, S. mitis, and S. oralis but only weakly by S. salivarius. Comparison of isogenic pairs of S. gordonii revealed a requirement for several surface proteins for maximum host cell invasion: glucosyltransferase, the sialic acid-binding protein Hsa, and the hydrophobicity/coaggregation proteins CshA and CshB. Deletion of genes for the antigen I/II adhesins, SspA and SspB, did not affect invasion. We hypothesize that peroxidogenesis and invasion of the cardiovascular endothelium by viridans group streptococci are integral events in the pathogenesis of infective endocarditis and atherosclerosis.  相似文献   
5.
Hürthle cell papillary thyroid carcinoma is a variant of papillary thyroid carcinoma (PTC). Its pathologic and clinical significance has not been well documented. The authors studied the relative incidence of Hürthle cell PTC and the relationship of Hürthle cell PTC to other variants of thyroid carcinoma. Three hundred eighty consecutive cases of thyroid carcinoma were reviewed to identify cases with focal or extensive areas of Hürthle cell PTC, classic PTC, Hürthle cell carcinoma (ie, non-Hürthle cell PTC), and follicular carcinoma. In addition, the status of lymphoid infiltrate in the tumor, stromal invasion with desmoplastic reaction, vascular invasion, and distant and lymph node metastasis were noted by microscopic examination, review of clinical charts, or both. A total of 24 (HCs) and 42 PTCs with Hürthle cells were identified. The latter category was divided into pure Hürthle cell PTC or extensive Hürthle cell (HPTC) (28 cases) and PTC or Hürthle cell carcinoma with focal areas of Hürthle cell PTC (14 cases). The Hürthle cell PTC/Hürthle cell carcinoma ratio was lower than that of PTC/follicular carcinoma (39:289) (P = 0.001). Follicular or solid structures were present in all HPTCs. HPTCs were associated with frequent stromal intrathyroid and extrathyroid invasion, but they tended to have a lower rate of lymph node metastasis (8/28) compared with classic PTC with stromal invasion (108:200) (P = 0.12) and a lower rate of distant metastasis (2:28) compared with Hürthle cell carcinoma (15:24) (P = 0.02) or follicular carcinoma (13:39) (P = 0.04). Warthin-like Hürthle cell PTC (10 cases) was associated with extrathyroid invasion in five cases. In Hürthle cell PTC associated with tall cell variant (10 cases), areas of gradual transition between Hürthle cell PTC and tall cell variant were identified. The latter variant showed the highest rate of extrathyroid stromal and vascular invasion with distant metastasis and patient death compared with all Hürthle cell PTCs and classic PTCs. In conclusion, Hürthle cell PTC is frequently associated with tall cell variant. It has a higher potential for extrathyroid invasion than classic PTC and has vascular invasion and distant metastasis characteristics intermediate between those of classic PTC and Hürthle cell carcinoma with or follicular carcinoma. Hürthle cell PTC tends to show a greater likelihood of extrathyroid invasion when associated with Warthin-like features and tall cell variant PTC, and higher vascular invasion and distant metastasis when associated with tall cell variant.  相似文献   
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Forty-two patients underwent resection of primary cardiac neoplasms at Stanford University Medical Center and the Palo Alto Veterans Administration Medical Center between 1961 and 1986. A total of 27 atrial myxomas, seven benign nonmyxomatous tumors, and eight malignant tumors were resected. The mean age was 47 years (range 8 to 79) in 27 female and 15 male patients. The clinical presentations included congestive heart failure in 24 patients, palpitations in nine, neurologic symptoms in six, recurrent cardiac tamponade in three, vasculitis in two, and chest pain in two. Thirty-one of 34 benign lesions were completely resected, although one patient required cardiac transplantation to resect completely an "inoperable" benign tumor. All gross tumor was resected in four of eight patients with malignant lesions. All patients survived operation, but three with malignant disease died within 30 days. Late outcome was known for 41 of 42 (98%) patients. Total follow-up for the series was 200.1 patient-years, for an average of 4.7 years (range 1 month to 18 years). Excellent early and late results were obtained in patients with benign lesions, as there was no known tumor recurrence even if resection was incomplete. Effective palliation and local control of disease is possible with extensive resection of malignant primary tumors, but more effective adjuvant therapy will be necessary to improve long-term prognosis.  相似文献   
7.
A prospective study was done on 99 consecutive patients who underwent distraction elbow arthroplasty and postoperative continuous passive motion from 1986 to 1992. Postoperative axillary catheter infusion in 73 patients was compared with patient-controlled analgesia-opioid treatment in 26 patients. Group comparisons for analgesia, complications, time to initiation, and tolerance of postoperative continuous passive motion were made. The postoperative axillary catheter infusion group was more comfortable and had better postoperative continuous passive motion compliance than did the patient-controlled analgesia-opioid group. The postoperative axillary catheter infusion group had a 2.7% (2 of 73) incidence of respiratory toxicity. There was an 11.5% (3 of 26) incidence of respiratory depression in the patient-controlled analgesia-opioid group. Final arc range of motion was similar between postoperative axillary catheter infusion and patient-controlled analgesia-opioid groups. The data support the hypothesis that postoperative axillary catheter infusion provides better patient comfort and earlier postoperative continuous passive motion initiation, but they do not show additional improvement in the final arc of motion after distraction elbow arthroplasty as compared with a patient-controlled analgesia-opioid treatment group.  相似文献   
8.
The tricyclic compound 2,5-bis(5-hydroxymethyl-2-thienyl)furan (NSC 652287) has shown a highly selective pattern of differential cytotoxic activity in the tumor cell lines comprising the National Cancer Institute (NCI) Anticancer Drug Screen. The mechanism underlying the selective cytotoxicity is unknown. We hypothesized that differential sensitivity to the compound observed in several renal tumor cell lines could be the result of selective accumulation or differential metabolism of this agent. We demonstrated here that the capacity of certain renal cell lines to accumulate and retain the compound, determined by accumulation of [14C]NSC 652287-derived radioactivity and by flow cytometric determination of unlabeled compound, paralleled the sensitivity of the renal cell lines to growth inhibition by NSC 652287: A-498 > TK-10 > ACHN approximately/= to UO-31. The ability of the cell lines to metabolize [14C]NSC 652287 to a reactive species capable of binding covalently to cellular macromolecules also directly correlated with sensitivity to the compound. Different patterns of metabolites were generated by relatively more drug-sensitive cell lines in comparison with drug-resistant cell lines. The metabolizing capacity for NSC 652287 was localized primarily to the cytosolic (S100) fraction. The rate of metabolism in the cytosolic fraction from the most sensitive renal cell line, A-498, was faster than that observed in the cytosolic fractions from the other, less sensitive cell lines. The data support the hypothesis that both selective cellular accumulation and the capacity to metabolize NSC 652287 to a reactive species by certain renal carcinoma cell types are the basis for the differential cytotoxicity of this compound class.  相似文献   
9.
Several methods for obtaining colon epithelial cells in suspension were compared. The largest number of epithelial cells per gram of colon was obtained in suspension when the colon was dissociated with 0.1% Pronase. Fivefold more cells per gram of tissue were obtained from the proximal 5 cm of colon than from the terminal 5 cm of colon. Several well-defined types of cells were observed in low frequency. They have not been described previously in normal colon. Suspensions of cells from colons of F344 rats always contained copious mucoid gel that was partially eliminated by washing the cells three times in culture medium with 10% fetal calf serum. Velocity sedimentation in a previously described isokinetic gradient of Ficoll in tissue culture medium permitted the separation of epithelial cells from lymphocytes and red blood cells. Type 2 cells, believed to be a subpopulation of epithelial cells, were obtained in a maximum purity of 95.7 +/- 1.2%. The frequency of 8 other cell types and their purification, when possible, are presented. Epithelial cells were separated from most bacteria and could be cultured with antibiotics after separation in the density gradient.  相似文献   
10.
BACKGROUND: Growth factor use has been shown to ameliorate chemotherapy-induced neutropenia, leading to shorter hospital stays and lower use of parenteral antibiotics, two costly areas of cancer treatment. Prior reports on pediatric patients have shown evidence of cost savings in some studies, but no such evidence in others. In this study a retrospective analysis compared the costs of inpatient supportive care for pediatric patients with T-cell leukemia and advanced lymphoblastic lymphoma enrolled in a Pediatric Oncology Group trial. PROCEDURE: Patients 1-22 years of age were randomized to receive either granulocyte colony-stimulating factor (G-CSF; n = 45) or no G-CSF (n = 43) following induction and two cycles of maintenance therapy. There were no significant differences in neutropenia-related outcomes during the induction phase. During maintenance therapy, G-CSF patients had significantly fewer days to an ANC >500 cells/microl and a trend towards fewer days of hospitalization. Data on resource utilization were tabulated from case report forms. Costs were imputed from national data on hospitalization costs, average wholesale prices of pharmaceuticals, and patient billing information from a single institution. RESULTS: Total median costs of supportive care were $34,190 for patients receiving G-CSF and $28,653 for patients not receiving G-CSF (P > 0. 05 for the cost difference). Sensitivity analyses demonstrated that the total cost difference was not statistically significant, even in scenarios that included reasonable variations in estimates of the range of the length of stay, antibiotic regimen, and dosage and cost of G-CSF. CONCLUSIONS: In the setting of pediatric leukemia, the cost of growth factor may offset potential savings from shorter hospital stays or lower antibiotic use, a finding consistent with that from the Children's Cancer Study Group.  相似文献   
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