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101.
OBJECTIVE: This study was performed to evaluate the evolution of peripheral lung adenocarcinomas using CT findings and histologic classification related to tumor doubling time. MATERIALS AND METHODS: The subjects were 34 patients, each with an adenocarcinoma smaller than 3 cm. All patients underwent chest radiography and 10 of them had previously undergone CT more than 6 months before surgery. Tumor doubling time was estimated by examining sequential radiographs using the method originally described by Schwartz. Tumor growth was also observed by studying the changes on CT in the 10 patients who had previously undergone CT. The histologic classification (types A-F) was evaluated according to the criteria of Noguchi et al. RESULTS: Five (83%) of the six adenocarcinomas with tumor types A or B showed localized ground-glass opacity on high-resolution CT. All six tumors had a tumor doubling time of more than 1 year. Fifteen (71%) of the 21 tumors with type C showed partial ground-glass opacity mixed with localized solid attenuation on high-resolution CT. Ten (48%) of these 21 type C tumors had a tumor doubling time of more than 1 year. In types B and C, the solid component or the development of pleural indentation and vascular convergence increased during observation before surgery. All seven tumors with types D, E, and F showed mostly solid attenuation, and the tumor doubling time was less than 1 year in six (87%) of the seven tumors. CONCLUSION: Two main types of peripheral lung adenocarcinoma exist. The first type appears on CT as a localized ground-glass opacity with slow growth, and the other appears as a solid attenuation with rapid growth.  相似文献   
102.
PURPOSE: The PSA level of prostate cancer patients generally declines after endocrine therapy, but elevates when the cancer relapses in most cases. However, the rate of elevation differs with the case. We investigated the PSA doubling time (PSA-DT) of the prostate cancer patients whose PSA declined after endocrine therapy and later re-elevated, and investigated the relationship with other parameters. PATIENTS AND METHODS: We investigated 55 prostate cancer patients who underwent endocrine therapy between 1991 and 1998. Their PSA re-elevated continuously after their PSA fell below 10 ng/ml after the endocrine therapy as the first line treatment. First, the correlation coefficients with time and PSA were calculated in order to decide whether their PSA elevation was exponential or linear. PSA-DT was calculated thereafter, and compared with the clinical stage, pathological differentiation, clinical relapse style, time from the beginning of the therapy to PSA relapse, pre-treatment PSA value, and prognosis. The relationship between PSA-DT and each clinical parameter was tested using the Kruskal-Wallis test. Differences in survival rates and PSA-DT were calculated using the log-rank test. RESULTS: PSA elevated exponentially after cancer relapsed. PSA-DT in all cases ranged from 0.5 to 26.3 months, with an average of 4.4 +/- 4.8 (S.D.) months and the median was 2.5 months. PSA-DT was significantly (p < 0.01) short when the pre-treatment clinical stage was high, the time from the beginning of the therapy to PSA relapse was short, or the pre-treatment PSA value was high. PSA-DT tended to be short when the pre-treatment pathological differentiation was low, but not significantly. PSA-DT tended to be short when the cancer relapsed as distant metastasis rather than regional relapse, but not significantly. Prognosis from the initial treatment and PSA relapse was significantly poor when the PSA-DT was short. CONCLUSIONS: PSA elevated exponentially in the relapsed prostate cancer patients after the endocrine therapy. PSA-DT was distributed in a very wide range, and this value was considered to reflect the malignant potential and prognosis of the cancer. PSA-DT may be useful for determining the strategy after relapse.  相似文献   
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Amino acid transport system L has been proposed to be one of the major nutrient transport systems at the blood-brain barrier. Using immunohistochemical analyses, a system L transporter LAT1 was shown to be expressed in the brain capillary endothelial cells in rats. Because LAT1 was coexpressed with 4F2 heavy chain which brings LAT1 to the plasma membrane, LAT1 is proposed to be functional in the plasma membrane of brain capillary endothelial cells. Both LAT1 and 4F2hc immunoreactivities were detected in a double line appearance surrounding endothelial cell nuclei, suggesting both proteins are present in the luminal and abluminal membranes. LAT1 is, thus, a blood-brain barrier system L transporter responsible for the permeation of aromatic or branched-chain amino acids and amino acid-related drugs such as L-DOPA.  相似文献   
105.
BACKGROUND: The minimum alveolar concentration (MAC)-awake is a traditional index of hypnotic potency of an inhalational anesthetic. The MAC-awake of xenon, an inert gas with anesthetic properties (MAC = 71%), has not been determined. It is also unknown how xenon interacts with isoflurane or sevoflurane on the MAC-awake. METHODS: In the first part of the study, 90 female patients received xenon, nitrous oxide (N2O), isoflurane, or sevoflurane supplemented with epidural anesthesia (n = 36 for xenon and n = 18 per group for other anesthetics). In the second part, 72 additional patients received either xenon or N2O combined with the 0.5 times MAC-awake concentration of isoflurane or sevoflurane (0.2% and 0.3%, respectively, based on the results of the first part; n = 18 per group). During emergence, the concentration of an assigned anesthetic (xenon or N2O only in the second part) was decreased in 0. 1 MAC decrements every 15 min from 0.8 MAC or from 70% in the case of N2O until the patient followed the command to either open her eyes or to squeeze and release the investigator's hand. The concentration midway between the value permitting the first response to command and that just preventing it was defined as the MAC-awake. RESULTS: The MAC-awake were as follows: xenon, 32.6 +/- 6.1% (mean +/- SD) or 0.46 +/- 0.09 MAC; N2O, 63.3 +/- 7.1% (0.61 +/- 0.07 MAC); isoflurane, 0.40 +/- 0.07% (0.35 +/- 0.06 MAC); and sevoflurane, 0.59 +/- 0.10% (0.35 +/- 0.06 MAC). Addition of the 0.5 MAC-awake concentrations of isoflurane and sevoflurane reduced the MAC-awake of xenon to 0.50 +/- 0.15 and 0.51 +/- 0.16 times its MAC-awake as a sole agent, but that of N2O to the values significantly greater than 0.5 times its MAC-awake as a sole agent (0.68 +/- 0.12 and 0.66 +/- 0.14 times MAC-awake; P < 0.01, analysis of variance and Dunnett's test). CONCLUSIONS: The MAC-awake of xenon is 33% or 0.46 times its MAC. In terms of the MAC-fraction, this is smaller than that for N2O but greater than those for isoflurane and sevoflurane. Unlike N2O, xenon interacts additively with isoflurane and sevoflurane on MAC-awake.  相似文献   
106.
BACKGROUND: Although anesthesia with xenon has been supplemented with fentanyl, its requirement has not been established. This study was conducted to determine the plasma concentrations of fentanyl necessary to suppress somatic and hemodynamic responses to surgical incision in 50% patients in the presence of 0.7 minimum alveolar concentration (MAC) xenon. METHODS: Twenty-five patients were allocated randomly to predetermined fentanyl concentration between 0.5 and 4.0 ng/ml during 0.7 MAC xenon anesthesia. Fentanyl was administered using a pharmacokinetic model-driven computer-assisted continuous infusion device. At surgical incision each patient was monitored for somatic and hemodynamic responses. A somatic response was defined as any purposeful bodily movement. A positive hemodynamic response was defined as a more than 15% increase in heart rate or mean arterial pressure more than the preincision value. The concentrations of fentanyl to prevent somatic and hemodynamic responses in 50% of patients were calculated using logistic regression. RESULTS: The concentration of fentanyl to prevent a somatic response to skin incision in 50% of patients in the presence of 0.7 MAC xenon was 0.72 +/- 0.07 ng/ml and to prevent a hemodynamic response was 0.94 +/- 0.06 ng/ml. CONCLUSIONS: Comparing these results with previously published results in the presence of 70% nitrous oxide, the fentanyl requirement in xenon anesthesia is smaller than that in the equianesthetic nitrous oxide anesthesia.  相似文献   
107.
Objective: To compare treatment patterns, persistence and adherence between fixed-dose combinations (FDCs) and two-pill combinations (TPCs) of oral antidiabetic drug (OAD) classes in Japanese patients with type 2 diabetes mellitus (T2DM) using administrative claims databases (Japan Medical Data Center [JMDC] and Medical Data Vision [MDV]).

Methods: This was a retrospective, longitudinal cohort analysis conducted between 2011 and 2015, in patients with T2DM receiving OADs as FDC or TPC. Outcomes included prescribing patterns, treatment persistence and adherence.

Results: Data from 3474 and 3066 patients receiving FDCs, and 4325 and 5192 patients receiving TPCs from the JMDC and MDV databases, respectively, was extracted. The most common OAD combination received by over half of all patients was dipeptidyl peptidase-4 inhibitor (DPP-4i) + thiazolidinediones (TZDs) (64.1% [JMDC] and 70.5% [MDV]). Overall, 12-month persistence rates were higher in patients receiving FDCs compared with TPCs (70.4 vs. 66.2% [JMDC], 75.6 vs. 55.7% [MDV]). In the JMDC population receiving FDCs or TPCs, persistence rates were highest with DPP-4i schedules (67.5–83.5%). Median time to discontinuation was significantly longer with biguanide?+?TZD, and DPP-4i?+?TZD FDC schedules (p < .05) than TPC; adherence rates were ≥80% across all antidiabetic drug classes in both database populations.

Conclusions: Persistence with and adherence to OADs in Japanese patients with T2DM were greater with FDCs than with TPCs, which may suggest increased patient satisfaction due to reduced treatment burden. Further studies are warranted to investigate the impact of adherence and persistence of FDCs of OADs on glycemic control.  相似文献   

108.

Background

Comprehensive Care for Joint Replacement (CJR) is a Medicare initiative to test the impact of holding a hospital accountable for services provided during an episode of care for a lower extremity joint arthroplasty on costs and quality. This study examines whether hospital participation in CJR is associated with having programs focused on improving posthospitalization care or reducing costs using a survey of orthopedic surgeons.

Methods

Seventy-three (of 104) orthopedic surgeon members of the Hip Society, a national professional organization of hip surgeons, completed the survey.

Results

Surgeons practicing in CJR hospitals were more likely to report that their hospital had implemented programs focused on improving posthospitalization care or reducing costs. Surgeons in CJR hospitals were significantly more likely to report that the hospital had a narrow network of skilled nursing facilities to enhance care and limit length of stay in skilled nursing facilities (83% vs 47%, P < .01). Surgeons in CJR hospitals were also more likely to report the hospital provides incentives or some type of gainsharing. There were no statistically significant differences in implementation of having programs to reduce costs or improve care during hospitalization.

Conclusion

Participation in CJR is associated with higher utilization of hospital practices aimed at improving postdischarge care and higher utilization of linking surgeon compensation to cost and quality.  相似文献   
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