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91.
Initial experience with the technique of "kissing balloon" angioplasty is described in 52 patients undergoing coronary angioplasty. Guiding catheters employing both the femoral and brachial approach were used in all but two of the coronary angioplasties and, in addition, the bilateral femoral approach was used in the renal and peripheral angioplasties. Initial success was achieved in 51 (98%) patients. Abrupt closure requiring urgent coronary revascularization occurred in one patient six hours following the completion of the procedure. Another patient developed a new Q-wave on the electrocardiogram and moderate elevation of CPK-MB fraction following the procedure due to loss of a diagonal branch. No deaths occurred in this series. Angiographic restenosis developed in ten patients. In the recurrence group, five had repeat kissing balloon angioplasty, two had repeat single vessel angioplasty, and three patients chose elective surgical revascularization. Based on our experience, the technique of kissing balloon coronary angioplasty can be performed safely utilizing the brachio-femoral technique. The risk of major side branch occlusion can be minimized with this technique and the overall complication rate does not significantly differ from that of our experience in single vessel coronary angioplasty. Patient selection criteria are based upon the angiographic relationship of the major branch to the side branch and is important in determining the initial and long-term success of this technique.  相似文献   
92.
Long-term follow-up of drug abusers with intravenous talcosis   总被引:4,自引:0,他引:4  
Six patients who injected talc containing drugs intended for oral use were assessed over a period of ten or more years from the time of initiation of this habit. Despite discontinuation of the drug abuse, all developed severe respiratory disability and three died from their disease. An evolving spectrum of roentgenographic and functional patterns is considered to be virtually diagnostic of this disorder. Roentgenographically, an initial diffuse, pin-point micronodularity subsequently becomes associated with conglomerates, usually in the upper lobes, closely resembling the progressive massive fibrosis (PMF) of the pneumoconioses. The lower lobes, on the other hand, become relatively translucent, in some instances with bulla formation and the development of pneumothorax. Pulmonary function, initially with both restrictive and obstructive features, eventually becomes markedly obstructive with hyperinflation and air trapping. At this late stage, pathologic examination reveals emphysema in addition to the granulomatous inflammation and fibrosis surrounding the talc particles in the pulmonary interstitium.  相似文献   
93.
Addition of increasing doses of synthetic growth hormone-release inhibiting hormone (GH-RIH) leads to a progressive decrease of the basal and N6monobutyryl cyclic AMP-,theophylline- and prostaglandin E2-induced release of immunoreactive growth hormone (GH) and thyrotropin (TSH) release from rat anterior pituitary cells in monolayer culture. A halfmaximal effect is measured at 3 × 10?9 M GH-RIH while a maximal inhibition to 10–20% of the control level is found at 1 × 10?7 M. Using rat hemipituitaries and measurement of GH release by both polyacrylamide gel electrophoresis and radioimmunoassay, a maximal effect of GH-RIH was found in the first 5 min of incubation. The inhibitory effect of GH-RIH on GH release remained constant for at least 3 h. GH-RIH does not affect the basal or induced release of prolactin and luteinizing hormone nor the high K +-induced release of GH and TSH.  相似文献   
94.
BACKGROUND & AIMS: Rofecoxib, an inhibitor of the inducible cyclooxygenase (COX)-2 enzyme, appears not to cause acute gastroduodenal injury or chronic ulceration. To attribute this to COX-2 selectivity with sparing of gastric mucosal prostaglandin synthesis requires direct proof. METHODS: Twenty-four healthy, nonsmoking Helicobacter pylori-negative volunteers were randomized to 1 of 2 separate concurrent blinded crossover studies. Sixteen volunteers received rofecoxib, 50 mg once daily, for 5 days in one treatment period and placebo in the other. Eight volunteers similarly received naproxen, 500 mg twice daily, and placebo. On day 5 of each period, antral mucosal prostaglandin E2 (PGE2) synthesis was measured by radioimmunoassay after vortexing for 3 minutes. Whole blood COX-1 activity was measured as serum thromboxane (TXB)2- and COX-2 activity as lipopolysaccharide (LPS)-induced PGE2. RESULTS: Naproxen decreased gastric mucosal PGE2 synthesis by 65% (90% confidence interval [CI], 53%-74%; P = 0.001 vs. placebo) in contrast to an 18% increase after rofecoxib (90% CI, -11% to 57%; P = 0.313 vs. placebo). Naproxen also significantly inhibited both serum TXB2 by 94% and LPS-induced PGE2 production by 77% (both P < or = 0.002 vs. placebo), but rofecoxib only inhibited COX-2-dependent LPS-induced PGE(2) (by 79%; P < 0.001 vs. placebo). CONCLUSIONS: Rofecoxib (50 mg) lacked naproxen's ability to reduce the availability of gastroprotective prostaglandins.  相似文献   
95.
96.
Background: Helicobacter pylori infection has protean effects on gene expression in the host gastric mucosa, which have been investigated by gene chip analysis in vitro. In this study the effects of H. pylori infection on host gene expression in the gastric antral mucosa in patients were examined. Methods: One gastric antral biopsy was obtained from a total of 18 untreated patients undergoing routine endoscopic evaluation of chronic abdominal complaints. Nine patients had histologic evidence of H. pylori infection and 9 age- and sex-matched patients had no histologic evidence of H. pylori infection. A microarray analysis was performed using a gene chip containing 35,000 human expressed sequence tags on RNA extracted from endoscopic, gastric antral biopsies, and average gene expression among infected and uninfected patients was compared. Results: Underexpressed genes in infected patients' mucosa included gastric intrinsic factor and several metallothionein isoforms. Overexpressed genes in infected patients' mucosa comprised MHC Class II molecules, immunoglobulin and B-cell activation genes, as well as genes known to induce apoptosis. Changes in expression were confirmed for a subset of genes by SYBR green real-time PCR. Conclusions: Microarray analysis of antral biopsies from patients with and without H. pylori infection revealed differential expression of metal regulatory, immunity and inflammation-related genes.  相似文献   
97.
Recognition and compensation are two valuable tools for nurse satisfaction and retention. A clinical ladder program is one way that facilities can recognize and reward nurses. The ANNA Administration Special Interest Group has developed the Nephrology Nurses' Clinical Ladder as a framework to help guide facilities in developing clinical ladder programs to meet their needs. This document is meant to serve as a template, allowing individual nephrology programs to tailor the clinical ladder program to meet their specific organizational structure and needs, thus allowing for recognition of professional role development in all nephrology arenas.  相似文献   
98.
The effects of cimetidine (CIM) (an inhibitor of the hepatic microsomal monooxygenase system) on the metabolism and hepatotoxicity of trichloroethylene (TRI) were studied in male Sprague-Dawley rats. Rats were given three doses of 120 mg/kg i.p. (low-dose regimen) of CIM at 0, 6 and 11 h for 1 day, or ten doses of 200 mg/kg (high-dose regimen) at 8, 11, 14 and 17 h for 2 days and 8 and 11 h on 3rd day. Trichloroethylene (0.5 or 0.65 ml/kg) was administered i.p. 1 h after 2nd dose (low-dose regimen) or 9th dose (high-dose regimen) of CIM. In the low-dose regimen study, the activity of hepatic microsomal aminopyrine N-demethylase was decreased 1 and 5 h after the second dose and 7 h after the third dose of CIM, but became normal 20 h after the last dose. The cytochrome P-450 content and the activities of aniline hydroxylase and epoxide hydratase remained unchanged. Trichloroethylene at both dose levels produced liver toxicity, as verified by increase in activities of SDH and SGPT as well as by liver histology. Cimetidine alone had no such effect. An apparent reduction in TRI toxicity by CIM (at both dose regimens) could be observed histologically. The biochemical tests (SDH and SGPT) corroborated the histological changes only when TRI was given at a dose of 0.5 ml/kg combined with a high-dose regimen of CIM. Cimetidine at both dose regimens had a tendency to decrease the in vivo metabolism of TRI.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
99.
Alcohol dehydrogenase (ADH) and aldehyde dehydrogenase (ALDH) activities were determined in adult flies from several Drosophila species endowed with widely different tolerance to ethanol (ETOH). Plotting ALDH against ADH activities resulted in a high correlation coefficient (r = 0.966). This finding was confirmed in developmental studies. From early larval stage up to late adult life, DH and ALDH activities demonstrated almost parallel profiles. In the highly ETOH tolerant species D. melanogaster (D.m.), ADH and ALDH profiles were U-shaped: high activities in larvae, low activities in pupae and high activities in adults. In D. simulans (D.s.), a species less tolerant to ETOH, the profiles were L-shaped: high activities in larvae but low activities in both pupae and adults. Interestingly, similar activities (ADH and ALDH) were observed in the larvae of both species. Subcellular distribution studies of larval ALDH in both species revealed that the total ALDH activity is largely contributed by a mitochondrial high affinity enzyme. ALDH activity, clearly distinguishable from aldehyde oxidase (ALDOX), was visualized through analytical isoelectric focusing of the subcellular fractions. The estimated pIs for D.m. and D.s. were 4.9 and 5.2 respectively, thus different from those of ADH. The key biological role initially attributed to Drosophila ALDH is further supported by the present data. In addition the Drosophila developmental model opens new avenues for research on the study of genetic regulation of ADH and ALDH expression.  相似文献   
100.
Although little is known regarding potential socioeconomic or racial bias in the recording of Parkinson's disease (PD) on death certificates, studies of incidence, prevalence, and the etiology of PD frequently rely on this type of data. A national population-based survey was linked to death certificate data to investigate the concordance of PD reported on death certificates for persons reporting PD during life. Logistic regression was used to identify independent factors associated with differential reporting of PD at death. Among decedents with PD reported during life, 54.8% had PD recorded on the death certificate. Nearly 70% of persons in higher income categories had PD recorded at death compared to 35.4% for those earning $10,000 or less. Age and gender adjusted odds of having PD recorded at death was 2.3 (1.1-3.9), for those with an annual income of $35,000 or more. Income differences remain significant in multivariable models after controlling for age, gender, race, census region, family size, rural residence, and number of chronic medical conditions. In conclusion, this study found socioeconomic bias in the reporting of PD at death. This bias is large enough to confound death certificate-based investigations of incidence, prevalence, and risk factors that differ across socioeconomic strata.  相似文献   
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