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61.
BACKGROUND: Double parathyroid adenomas occur in 2% to 15% of primary hyperparathyroidism cases, but the very existence of double adenomas has been controversial. This study was conducted to evaluate the clinical significance and anatomic distribution of parathyroid double adenomas. STUDY DESIGN: Mono-institutional retrospective study of the medical records of 183 unselected consecutive patients who underwent intervention for primary hyperparathyroidism between 1996 and 2003. RESULTS: A total of 14 (7.65%) patients were found to have double parathyroid adenomas. Intraoperative parathyroid hormone (PTH) levels were measured in every case. Two enlarged parathyroid glands were identified in four possible configurations: two both superior, one both inferior, two both right, three both left, two right superior and left inferior, and three left superior and right inferior. There was a preferential crossed bilateral distribution of double adenomas. In all patients, intraoperative PTH levels dropped by at least 50% from baseline after removal of both abnormal parathyroid glands. In this series, no patient developed persistent hypoparathyroidism or had recurrent laryngeal nerve injuries or neck hematoma. All patients remained normocalcemic 9 to 96 months postoperatively. One patient had persistently elevated PTH values with normal serum calcium levels. CONCLUSION: The drop in intraoperative PTH levels and maintenance of normocalcemia postoperatively confirm previous reports that double adenomas do exist and are not simply missed cases of four-gland hyperplasia. There was a preferential crossed bilateral distribution of double adenomas in this series.  相似文献   
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We report a case of severe Beckwith-Wiedemann syndrome (BWS) in a fetus at 16 weeks of gestation. This presentation, incompatible with life, included a giant omphalocele and absence of abdominal wall musculature with extremely dilated bladder, as in the "prune belly" sequence. Adrenal cytomegaly pointed to BWS. Molecular analysis confirmed the diagnosis of BWS and showed an isolated demethylation of the KCNQ1OT1 gene. This report demonstrates that lethal fetal abdominal wall defects associated with adrenal cytomegaly are linked to epigenetic change of the 11p15 imprinted region.  相似文献   
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OBJECTIVE: We conducted this retrospective study to determine accuracy of frozen section examination of endocervical margin during cold knife conization. METHODS: Between June 1993 and June 2001, 310 consecutive patients underwent cervical conization for squamous intraepithelial lesion or stage IA1 cervical cancer. Before 1997, the surgical specimens of 149 patients were processed following a standard pathological procedure (historical group). After 1997, a frozen section of the upper endocervical margin was processed during surgery for 161 patients. If the upper endocervical margin was involved with intraepithelial neoplasia, the surgeon performed a second resection if possible. Results of the frozen section examination were compared with the final diagnoses to determine sensitivity, specificity, and positive and negative predictive values. The usefulness of this procedure was evaluated by comparison of positive margin status rate with the one of the historical control group. RESULTS: For the diagnosis of intraepithelial neoplasia involving the endocervical margin, the sensitivity, specificity, and positive and negative predictive values of frozen section were 91%, 100%, 100%, and 98%, respectively. Eleven patients had definitive positive endocervical margin in the frozen section group (three false negatives, six patients without additional resection, and two patients with intraepithelial neoplasia involving the upper margin of the additional resection) and 17 patients in the historical group (P =.16). CONCLUSION: Frozen section examination of the endocervical margin of cervical specimen obtained during cold knife conization is highly accurate. Its clinical relevance has to be demonstrated in a multicenter study.  相似文献   
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Objective: We hypothesized that among neonates with necrotizing entercolitis (NEC), important epidemiologic and outcome differences exist between those with early-onset vs. those with late-onset NEC.Methods : We reviewed all records of neonates cared for in the King Fahad University Hospital during the past ten years who had the diagnosis of NEC. We separated cases into two groups depending on age at diagnosis. Specifically, we termed “early-onset” those cases diagnosed during the first seven days of life, and “late-onset” those diagnosed thereafter. We compared, in the two groups, gestational age, clinical signs at onset, laboratory data, surgical findings, complications, and mortality.Results: From 1989 to 1999, 37 cases of stage lla (or higher) NEC were diagnosed; 25 “early-onset “ and 12 “late-onset”. Neonates with “earlyonset” NEC were more mature (35.4 ±2.5 weeks gestation) than those with “late-onset” (27.7 ±2.8 weeks, P = 0.0001), were more likely to have feedings begun in the first 48 hours of life (P = 0.0002), and more likely to have feeding increments of >25 ml/kg/day (P=0.03). Neonates with “late-onset” NEC were more likely to present with vomiting (P=0.003) and apnea (P=0.001), and were more likely to have ileal rather than colonic necrotic lesions, short bowel syndrome, and mortality (P = 0.03).Conclusion: During the past 10 years at the King Fahad University Hospital, cases of early and late-onset NEC have had distinct epidemiologic and outcome features. Recognizing these differences may be useful in prognostication and counseling  相似文献   
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BACKGROUND: Two-stage exchange arthroplasty remains the standard treatment of infection at the site of a total knee arthroplasty. The clinical and functional outcomes associated with the use of an articulating antibiotic spacer for two-stage revision for infection are not well established. We conducted a retrospective study to evaluate the outcomes associated with the use of the PROSTALAC articulating spacer between the first and second stages. METHODS: Fifty-eight patients underwent two-stage revision total knee arthroplasty for infection between January 1997 and December 1999. Of these, fifty-four were alive at the time of follow-up and forty-seven were available for inclusion in the present retrospective study. In all patients, a prosthesis of antibiotic-loaded acrylic cement (the PROSTALAC system) was implanted during the first stage after débridement. The amount of osteolysis that occurred between the stages and the range of motion of the knee joint were measured. After two years of follow-up, outcomes were assessed with use of the WOMAC, Oxford-12, and SF-12 instruments as well as a satisfaction questionnaire. RESULTS: At a minimum of two years (average, forty-one months) after revision arthroplasty, two patients (4%) had had a recurrence of infection. The amount of bone loss was unchanged between stages, and the range of movement of the knee improved from 78.2 degrees before the first stage to 87.1 degrees at two years. The average normalized WOMAC function and pain scores were 68.9 and 77.1, respectively; the average Oxford-12 score was 67.3; the average SF-12 mental and physical scores were 53.7 and 41.2, respectively; and the average satisfaction score was 71.7. CONCLUSION: A revision operation for infection at the site of a total knee replacement with use of an articulating spacer was associated with reasonable function and satisfaction scores. These findings may be related to the articulating features of the PROSTALAC system, which permits full active movement of the knee in the early postoperative period.  相似文献   
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THE CURRENT SITUATION: Preeclampsia is associated with increased risk of adverse maternal (abruptio placentae, HELLP syndrome, eclampsia.) and perinatal death. Its prevention, therefore, is of particular importance. The latter must be determined together with the group of women who would benefit from it. THE INTEREST OF ASPIRIN: The best studied preventive treatment is low dose aspirin. The various studies on low-dose aspirin have confirmed its safety in pregnant women. These studies, in small cohorts of selected patients at risk or in large series of women with moderate risk, show that the use of aspirin is associated with a 15% reduction in the risk of preeclampsia. OTHER THAN ASPIRIN: Other preventive treatments, such as calcium have not demonstrated their efficacy, or their effect requires confirmation, such as with anti-oxidants or low molecular weight heparin. IN PRACTICE: The prevention of preeclampsia currently relies on low-dose aspirin started at the beginning of pregnancy. The moderate benefit of such prevention justifies its administration in patients at high risk, selected on their obstetrical past history.  相似文献   
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BACKGROUND: The importance of apoptosis contra necrosis for ischemia/reperfusion (RP) and acute rejection in concordant rodent xenotransplantation is largely unknown. We explored this question by comparing rodent allo and concordant xenotransplants with different morphological methods to detect apoptosis and biochemical data on the levels of high-energy phosphates obtained with in vitro 31Phosphorous Magnetic Resonance Spectroscopy (31P MRS). More specifically, we applied a hitherto unused method in transplantation research, apoptosis specific biotin labeled oligonucleotides designed with a 10 base pair stem region and a 20 nucleotides large loop that form a hairpin like shape. The results obtained with this method were compared to results obtained with the more widely used in situ 3'-end labeling of DNA (TUNEL) assay and extraction and gel electrophoresis of labeled DNA (DNA laddering). METHODS: Cervical heart transplantations were performed between inbred Lewis (L) (RT1l) to L, L to DA (RT1a) rats, hamster (H) to H and H to L (X) (n=5 for all groups except for X, n=9). All hearts were subjected to 30 min of cold ischemia (+4 degrees C) and 6 h of RP before explantation. In vitro 31P MRS was used to determine the phosphocreatine (PCr), beta-adenosine triphosphate (beta-ATP) concentrations and the PCr/beta-ATP ratio of the transplants. We correlated the biochemical data to haematoxylin and eosin (H & E) stained tissue slides scored for rejection, infiltration of antibodies and complement depositions, DNA extraction and gel electrophoresis of labeled DNA (DNA laddering), in situ 3'-end labeling of DNA (TUNEL) and the apoptosis specific hairpin probe assays scoring. RESULTS: The rejection score of the xeno grafts differed significantly compared to their syngeneic hamster to hamster controls (2.40 +/- 0.25 vs. 1.20 +/- 0.20; P=0.005) and they had a significantly higher TUNEL score, 228 +/- 15 vs. 2.44 +/- 0.32 (P=0.009), that correlated to changes in PCr concentration (P<0.001) and to the PCr/beta-ATP ratio (P=0.01). The uptake was mainly (90-95%) located to 1-2 microm large extra cellular 'granule'. A picture resembling early necrosis was seen on the H & E stainings and reflected in the Billingham rejection score above. CONCLUSIONS: After 6 h of RP the onset of acute rejection in the concordant hamster xeno hearts displayed features of early, possibly mitochondrial, necrosis, but not apoptosis, which correlated to changes in the PCr concentration and the PCr/beta-ATP ratio. The mechanism for the early rejection observed is unclear and might be caused by other factors in the sera apart from cellular components, antibodies and complement factors. Identification of the underlying mechanisms could enable us to design rational therapies that prevent activation of the recipient's innate immune response.  相似文献   
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