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31.
Abscess formation from spilled gallstones after laparoscopic cholecystectomy is infrequent. However, if an abscess does form and contains the spilled stones simple percutaneous drainage will not resolve the dilemma of a recurrent abscess. Open drainage has previously been recommended to remove the retained stones and decrease recurrent abscess formation. We report two cases in which the retained stones within an abscess were successfully removed using a percutaneous minimally invasive urological technique.  相似文献   
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33.
Regarding the widespread use of organophosphorous pesticides (OP) especially malathion in environment and reported cases of muscle disturbances in human and animal, the present work was undertaken to explore effects of malathion subchronic exposure on rat leg skeletal muscle glucose metabolism by measuring key enzymes of glycogenolysis and glycolysis. Malathion was administered through food for 4 weeks at concentrations of 100, 200, and 400ppm to rats. Activities of enzymes including glycogen phosphorylase (GP), hexokinase (HK), and phosphofructokinase-1 (PFK) were measured in skeletal muscle homogenate of exposed rats. Levels of glucose and insulin were measured in blood. Four weeks administration of malathion at doses of 200 and 400ppm increased blood glucose concentrations to 44.4 and 60.6% of control, respectively. Malathion at doses of 200 and 400ppm increased blood insulin concentration to 36.6 and 143.2% of control, respectively. Malathion at doses of 100, 200, and 400ppm increased muscle PFK activity to 40.4, 53.5, and 83.1% of control, respectively. Malathion at doses of 400ppm increased skeletal muscle GP to 91.6% of control. Skeletal muscle HK was not influenced by malathion treatment. It is concluded that malathion influences muscle glycogenolysis and glycolysis as well as secretion of insulin from pancreas which all may explain diabetic potential of malathion.  相似文献   
34.
Acheson EM  Kheirabadi BS  Deguzman R  Dick EJ  Holcomb JB 《The Journal of trauma》2005,59(4):865-74; discussion 874-5
BACKGROUND: QuikClot powder (QC), chitosan dressing (CD), and fibrin sealant dressing (FSD) are new hemostatic products touted to be more effective in controlling severe extremity bleeding than the current standard gauze dressing. All have been utilized in the global war on terrorism. Our objective was to evaluate the hemostatic efficacy of these three products in a model of severe extremity arterial hemorrhage that could not be stopped by standard gauze treatment. METHODS: A model of severe extremity arterial hemorrhage was developed in swine that was 100% fatal with standard gauze application and manual compression. The Army Field Bandage (AFB) was the standard gauze control. Anesthetized animals (n = 60, 15/group, 37.7 +/- 2.5 kg) were splenectomized and instrumented. A reproducible femoral artery injury was created using a 6 mm aortic punch, and free bleeding was allowed for 45 seconds. Each hemostatic agent was applied twice with three-minute compressions. All products were applied on actively bleeding wounds through a pool of blood. Fluid resuscitation was started with the first compression and titrated to a mean pressure of 65 mm Hg. Animals were observed for 180 minutes or until death. Endpoints were percent survival, survival time, blood loss, resuscitation volume, wound temperatures and tissue histology. Data are expressed as mean +/- SD and analyzed by Fisher's exact, logrank, and nonparametric ANOVA tests. RESULTS: Baseline physiologic parameters were similar among groups. AFB did not produce hemostasis. QC also showed no hemostatic benefit, and QC treatment markedly increased maximum wound temperatures to an average of 70.8 +/- 4.2 degrees C (p < 0.001). CD stopped bleeding temporarily in only one animal. There were no survivors in the AFB, QC, or CD groups. CD numerically prolonged survival time (58.9 +/- 21.1 minute) compared with the control (38.4 +/- 24.7 minutes, p = 0.045) but the difference was not significant. FSD reduced bleeding (p < 0.05) and prevented exsanguination in 10/15 (2/3) animals, and resulted in a significantly longer average survival time (p < 0.0001). CONCLUSION: FSD was superior to other currently utilized hemostatic products in controlling lethal arterial hemorrhage in this model of a fatal extremity wound. CD showed some hemostatic benefit. The exothermic reaction of QC was significant and resulted in gross and histologic tissue changes of unknown clinical significance. Controlled human studies with the promising products are required.  相似文献   
35.
PURPOSE: We prospectively evaluated the impact of body mass index (BMI) and prostate gland size on operative time, estimated blood loss (EBL) and hospital stay (LOS) in patients undergoing laparoscopic radical prostatectomy at our institution. MATERIALS AND METHODS: A total of 70 consecutive laparoscopic radical prostatectomies were performed at our institution from May 2002 to April 2003. Patients who had pelvic lymphadenectomy were excluded. A total of 62 cases were available for analysis. Two cases were converted to open surgery. Perioperative data on each group were recorded, including patient age, height, weight, American Society of Anesthesiologists score, prostate specific antigen, operative time, EBL, time to regular diet and LOS. Pathology data, including specimen weight, Gleason score and the margin status, were reviewed. Patients were grouped into 3 categories based on obesity, as measured by BMI (25 or less, 26 to 29 and greater than 29 kg/m) and prostatic gland size (less than 30, 30 to 50 g, and greater than 50 gm). Furthermore, an analysis of our initial 20, middle 20 and last 22 cases was also performed. RESULTS: Mean patient age was 63 years and mean American Society of Anesthesiologists score was 2.4. Mean operative time was 247 minutes and average EBL was 413 cc. The average LOS in all groups was 2.2 days. There were no statistically significant differences in operative parameters (operative time, EBL or LOS) among the ideal body weight (BMI 25 kg/m or less), overweight (BMI 26 to 29) and obese (BMI greater than 29) groups. The initial 20 cases, the second 20 and the last 22 had similar operative time, EBL and LOS. The surgical margin positive rate in our series was 17.7% for all stages. Of the patients 82% were completely dry at 6 months. CONCLUSIONS: In our cohort of patient body mass index (25 or less, 26 to 29 and greater than 29 kg/m) did not have a significant impact on operative or postoperative morbidity. However, a positive correlation between prostate gland size (greater than 50 gm) and EBL approached but did not achieve statistical significance. Laparoscopic prostatectomy can be performed safely in obese patients and patients with a large prostate gland.  相似文献   
36.
In the present study, we have investigated the effects and interaction of CCK and GABAergic systems in the dorsal hippocampus of rats using the elevated plus-maze test of anxiety. Bilateral injection of different doses of CCK(8s) (0.01, 0.05 and 0.1 microg/rat) into the dorsal hippocampus (intra-CA1) decreased percentage of open arm time (%OAT) and open arm entries (%OAE) that are representative of anxiogenic-like behavior. The bilateral injection of three doses of LY225910, a selective CCK2 receptor antagonist (0.01, 0.1 and 0.5 microg/rat) produced significant anxiolytic behavior. Although muscimol (GABA(A+)) (0.1, 0.5 and 1 microg/rat, intra-CA1) produced dose dependent increase in %OAT and a slight increase in %OAE, bicuculline (GABA(A-)), (1, 2 and 4 microg/rat, intra-CA1) failed to change the anxiety profile. Both muscimol (0.1 microg/rat) and bicuculline (1 microg/rat), when co-administered with LY225910, reversed the effect of latter drug on anxiety but when co-administered with CCK8s (0.05 microg/rat) showed no effect on anxiety profile. In conclusion, it seems that both CCK and GABAergic systems not only play a part in the modulation of anxiety in the dorsal hippocampus of rats but also have demonstrated a complex interaction as well.  相似文献   
37.
Investigations using models of neurologic disease frequently involve quantifying animal motor activity. We developed a simple method for measuring motor activity using a computer-based video system (the Webcam system) consisting of an inexpensive video camera connected to a personal computer running customized software. Images of the animals are captured at half-second intervals and movement is quantified as the number of pixel changes between consecutive images. The Webcam system allows measurement of motor activity of the animals in their home cages, without devices affixed to their bodies. Webcam quantification of movement was validated by correlation with measures simultaneously obtained by two other methods: measurement of locomotion by interruption of infrared beams; and measurement of general motor activity using portable accelerometers. In untreated squirrel monkeys, correlations of Webcam and locomotor activity exceeded 0.79, and correlations with general activity counts exceeded 0.65. Webcam activity decreased after the monkeys were rendered parkinsonian by treatment with 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP), but the correlations with the other measures of motor activity were maintained. Webcam activity also correlated with clinical ratings of parkinsonism. These results indicate that the Webcam system is reliable under both untreated and experimental conditions and is an excellent method for quantifying motor activity in animals.  相似文献   
38.
Although the reductionist approach has served science well for 400 years, the accumulation of details can obscure the truth if the original premise is incorrect. One such premise has been that successful organ transplantation and bone marrow engraftment are fundamentally different outcomes involving separate and distinct mechanisms. Some historical clinical observations pointed to a different conclusion almost from the beginning and included clues about how to induce tolerance with the aid of immunosuppression.  相似文献   
39.
BACKGROUND AND PURPOSE: Nerve-sparing retroperitoneal lymphadenectomy (RPL) is performed in a significant number of patients to preserve ejaculation after treatment for testicular cancer. Identification and preservation of the sympathetic nerves may be challenging. Hydro-Jet technology has been utilized for various surgical applications. A small high-pressure stream of water is used to delineate surgical planes, with preservation of vascular and neural structures. We have examined the utility of this technology for RPL in a porcine model and in human subjects. MATERIALS AND METHOD: A Helix Hydro-Jet device (Erbe, USA) was used for all procedures. A high-pressure water-jet stream is directed through a small nozzle with a 120-microm inner radius for soft-tissue dissection. The upper pressure limit (range 0-2175 psi) is set using a digital monitor. The jet is initiated using a foot pedal, and the actual pressure is monitored. A pressure of 360 to 400 psi was used for experimental studies, which was decreased to 255 to 300 psi for human use. Three pigs underwent RPL using this technique. Subsequently, RPL was performed in five men with testicular cancer, being primary in two and postchemotherapy in three. The primary diagnosis was seminoma in one and non-seminomatous cancer in four. The patient with seminoma had a residual mass after chemotherapy. RESULTS: The procedures were completed successfully in all subjects. There were no intraoperative or postoperative complications. Hydro-Jet dissection permitted tissue selectivity, with preservation of vascular structures and sympathetic nerves. The soft tissue and lymphatics were removed with the high-pressure water stream assisted by blunt dissection. The nerve fibers were grossly resistant to the pressure used and were isolated individually. Dissection around the great vessels appeared to be safe, and no injury was observed with direct application of the jet. Lumbar arteries and veins and accessory vessels could be isolated safely. The estimated blood loss was minimal in animals and 300 to 800 mL in humans. CONCLUSIONS: Hydro-Jet dissection demonstrated tissue selectivity using a pressure range of 255 to 300 psi in humans. The vascular structures and sympathetic nerves were preserved. Our initial experience with this device for nerve-sparing RPL is encouraging.  相似文献   
40.
Apoptosis is associated with early changes in cell volume through a mechanism called apoptotic volume decrease (AVD). As volume-sensitive chloride channels (I(Cl,vol)) are known to play a key role in the regulation of cell volume, this study investigated the role of I(Cl,vol) and AVD in doxorubicin-induced apoptotic cell death in adult rabbit ventricular cardiomyocytes. Exposure of cardiomyocytes to 1 microm doxorubicin induced a rapid and significant reduction in cell volume of cardiomyocytes (average of 15%), i.e. AVD as well as increases in the early markers of apoptosis, annexin V labeling and caspase-3 activity. Doxorubicin also induced the activation of a current characterized as I(Cl,vol) on the basis of the external chloride sensitivity and pharmacological properties with the patch clamp technique. Doxorubicin-induced AVD and apoptosis were both abolished when cardiomyocytes were exposed to the I(Cl,vol) inhibitors 5-nitro-2-(3-phenylpropylamino) benzoic acid (NPPB) (0.1 mM) or indanyloxyacetic acid 94 (IAA-94) (10 microM). The crucial role of I(Cl,vol) during AVD and apoptosis was confirmed using C(2)-ceramide, another pro-apoptotic compound. These results demonstrate that activation of I(Cl,vol) plays a major role in the mechanism leading to cell shrinkage and apoptosis-induced AVD by agents such as doxorubicin or C(2)-ceramide in adult cardiomyocytes.  相似文献   
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