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911.
To identify the major outer surface proteins of Streptococcus agalactiae (group B streptococcus), a proteomic analysis was undertaken. An extract of the outer surface proteins was separated by two-dimensional electrophoresis. The visualized spots were identified through a combination of peptide sequencing and reverse genetic methodologies. Of the 30 major spots identified as S. agalactiae specific, 27 have been identified. Six of these proteins, previously unidentified in S. agalactiae, were sequenced and cloned. These were ornithine carbamoyltransferase, phosphoglycerate kinase, nonphosphorylating glyceraldehyde-3-phosphate dehydrogenase, purine nucleoside phosphorylase, enolase, and glucose-6-phosphate isomerase. Using a gram-positive expression system, we have overexpressed two of these proteins in an in vitro system. These recombinant, purified proteins were used to raise antisera. The identification of these proteins as residing on the outer surface was confirmed by the ability of the antisera to react against whole, live bacteria. Further, in a neonatal-animal model system, we demonstrate that some of these sera are protective against lethal doses of bacteria. These studies demonstrate the successful application of proteomics as a technique for identifying vaccine candidates.  相似文献   
912.
Influence of gelatine concentration and cross-linker ions of Ca2+ and Ba2+ was evaluated on characteristics of alginate hydrogels and proliferation behaviours of model adherent and suspendable stem cells of fibroblast and U937 embedded in alginate microcapsules. Increasing gelatine concentration to 2.5% increased extent of swelling to 15% and 25% for barium- and calcium-cross-linked hydrogels, respectively. Mechanical properties also decreased with increasing swelling of hydrogels. Both by increasing gelatine concentration and using barium ions increased considerably the proliferation of encapsulated model stem cells. Barium-cross-linked alginate-gelatine microcapsule tested for bone building block showed a 13.5?±?1.5-fold expansion for osteoblast cells after 21?days with deposition of bone matrix. The haematopoietic stem cells cultured in the microcapsule after 7?days also showed up to 2-fold increase without adding any growth factor. The study demonstrates that barium-cross-linked alginate-gelatine microcapsule has potential for use as a simple and efficient 3D platform for stem cell production and modular tissue formation.  相似文献   
913.
This study investigates if different diabetic treatment regimens affect diabetic foot ulcer healing. From January 2013 to December 2014, 107 diabetic foot ulcers in 85 patients were followed until wound healing, amputation or development of a nonhealing ulcer at the last follow‐up visit. Demographic data, diabetic treatment regimens, presence of peripheral vascular disease, wound characteristics, and outcome were collected. Nonhealing wound was defined as major or minor amputation or those who did not have complete healing until the last observation. Median age was 60.0 years (range: 31.1–90.1 years) and 58 cases (68.2%) were males. Twenty‐four cases reached a complete healing (healing rate: 22.4%). The median follow‐up period in subjects with classified as having chronic wounds was 6.0 months (range: 0.7–21.8 months). Insulin treatment was a part of diabetes management in 52 (61.2%) cases. Insulin therapy significantly increased the wound healing rate (30.3% [20/66 ulcers] vs. 9.8% [4/41 ulcers]) (p = 0.013). In multivariate random‐effect logistic regression model, adjusting for age, gender, smoking status, type of diabetes, hypertension, chronic kidney disease, peripheral arterial disease, oral hypoglycemic use, wound infection, involved side, presence of Charcot's deformity, gangrene, osteomyelitis on x‐ray, and serum hemoglobin A1C levels, insulin treatment was associated with a higher chance of complete healing (beta ± SE: 15.2 ± 6.1, p = 0.013). Systemic insulin treatment can improve wound healing in diabetic ulcers after adjusting for multiple confounding covariates.  相似文献   
914.
The aim of this study was to evaluate the effectiveness of total contact casting (TCC) in treating non‐healing diabetic foot ulcers in Lebanese diabetic patients. Twenty‐three diabetic patients were treated with TCC, and relevant data were collected retrospectively. Sixteen patients were analysed; the average duration of casting was 6 weeks, and 75% of the patients achieved complete ulcer closure without recurrence during one year of follow‐up and without any complications. TCC appears to be an effective treatment of diabetic foot ulcers.  相似文献   
915.
Sixty consecutive evaluable specimens from patients with non-Hodgkin's lymphoma (NHL) were studied for the incidence of polysomy of chromosome 12 by fluorescence in situ hybridization (FISH) with probes for the repetitive DNA sequence in the centromeric region of chromosome 12. Thirty-six samples were from follicular lymphomas (FLs), and twenty-four were from diffuse large cell lymphomas (DLCLs). Fifty-two specimens (86%) were obtained by fine-needle aspiration of a diseased node, seven (11.6%) were from involved bone marrows, and one specimen was from a pleural effusion. Twelve of the thirty-six (33%) cases with FL had trisomy 12 in 3-41% of the cells (median, 10%) (normal controls had three signals in 1.4 +M 0.7% of cells). Trisomy 12 was found in 62% of the patients who had had FL for more than 5 years. Nine of the twenty-four cases (37%) with DLCL had more than two copies of chromosome 12 in 4-92% of the cells (median, 78%), and all nine cases were of B-cell phenotype. Unlike FL cells, some DLCL cells had 4-6 copies of chromosome 12. In previously untreated patients, 54% of DLCLs and 26% of FLs had subpopulations of cells containing more than two copies of chromosome 12 (P = 0.04). Only 2/7 cases of DLCL with polysomy 12 had rearrangement of the BCL2 gene, indicating that the majority of DLCL cases with polysomy 12 did not result from histologic transformation of low grade follicular lymphomas. These data demonstrate that FISH of interphase cells is a sensitive method for detecting numerical abnormalities of chromosome 12 in NHL. The differences between FL and DLCL in the number of chromosomes 12 and the number of involved cells may be related to differences in the biology of these tumors. Genes Chrom Cancer 9:161-167 (1994). © 1994 Wiley-Liss, Inc.  相似文献   
916.
Treatment of male and female rats with carbon tetrachloride (CCl4, twice weekly, 0.2 ml/kg p.o.) and a 5% alcohol solution during four weeks evoked strong increments of the serum enzyme activities of the aminotransferases (GOT, GPT) and the sorbitol dehydrogenase (SDH). These occurred earlier and were more pronounced in male compared to female rats. Hepatic triglyceride contens as a measure of fatty infiltration was augmented three-fold both in males and females at the end of the experiment. Hepatic hydroxyproline contents were enhanced seven-fold in males, but only two-fold in females. It is concluded that female rats are less susceptible to CCl4-alcohol-induced liver damage, especially hydroxyproline accumulation which is explained by the known fact that females are more resistant against CCL4-hepatotoxicity as a consequence of a minor role of bioactivation in the metabolic degradation of CCO4 by females.  相似文献   
917.
A prospective phase II study was carried out in 48 patients with relapsed or refractory non-Hodgkin's lymphoma using paclitaxel 27.5 mg/M2 i.v. by continuous infusion over 24 hours daily on days 1, 2, 3, and 4 in combination with mitoxantrone 8 mg/M2 i.v. on day 1 and ifosfamide/mesna 1.33 grams/M2 i.v. daily on days 1, 2, and 3 (MINT). Responding patients completed four cycles of MINT and were consolidated with etoposide, solumedrol [methylprednisolone], high-dose cytarabine [Ara-C], and platinum (ESHAP). Forty-eight patients were entered in the study between 1994 and 1996 at The University of Texas M. D. Anderson Cancer Center. Overall response after the first four cycles of MINT was 67% (16% complete response [CR]+ 51% partial response [PR]) and after consolidation with ESHAP it was 49% (26% CR + 23% PR). Variables associated with an improved CR rate and better failure-free survival included the number of prior treatments and the response to prior treatment. A comparison with a similar group of patients treated with mesna, ifosfamide, mitoxantrone, and etoposide (MINE)-ESHAP revealed no major differences in outcome.  相似文献   
918.
Peptide YY (PYY) release was studied by measuring radioimmunoassayable PYY in the arterial plasma of anaesthetized rats receiving into the duodenum, ileum or colon either a complete semi-liquid meal (3 ml, 21 kJ) or elemental nutrients as isocaloric or isoosmolar solutions. PYY release induced by the intraduodenal meal peaked at 60 min and lasted more than 120 min. The integrated response of PYY over 120 min was larger when the meal was administered into the duodenum than into the ileum. The undigested meal induced no release of PYY over a 120-min period when administered into the colon. When injected into the duodenum in isocaloric amounts to the meal, glucose and amino acids led to the release of as much PYY as did the meal, whereas oleic acid led to the release of less PYY. Part of these responses were due to osmolarity, since administration of intraduodenal hyperosmolar saline led to the release of about half as much PYY as did hyperosmolar glucose. In moderate amounts, and injected as a solution isoosmolar to plasma, oleic acid was a major PYY releaser; the amounts released were at least two times larger when oleic acid was administered into the duodenum than into the ileum and colon. Isoosmolar glucose and amino acids led to the release of no PYY when injected into the duodenum, but were nearly as active as oleic acid in the colon. Short-chain fatty acids induced the release of PYY when injected into the colon, but not into the ileum. Hexamethonium suppressed PYY release induced by the intraduodenal meal, but did not change PYY release induced by glucose or oleic acid in the colon. Urethane anaesthesia did not reduce PYY release induced by the intraduodenal meal. These results suggest that two mechanisms at least contribute to PYY release in the rat. An indirect, neural mechanism, involving nicotinic synapses, is prominent in the proximal small intestine; the stimulation is transmitted to ileal and colonic L-cells by undetermined pathways, but contact of nutrients with L-cells is not needed. Another mechanism, probably direct and quantitatively smaller, occurs in the distal intestine when nutrients come into contact with the mucosa containing L-cells. Glucose, fatty acids and amino acids stimulate differentially the proximal and distal mechanisms.  相似文献   
919.
920.
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