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41.
A 47-year-old male from India was treated for the rare condition of bilateral multifocal intraocular infestation with Cysticercus cellulosae, the larval form of Taenia solium. The intravitreous parasite in the left eye was removed via pars plana vitrectomy. A subretinal cysticercus in the right eye, which caused a rhegmatogenous retinal detachment, was removed via sclerotomy during the scleral buckling procedure. An additional peripapillary subretinal cyst could not be removed. A subconjunctival cysticercus was incidently found and removed at the time of surgery. The patient returned to India six weeks after surgery and is doing well.  相似文献   
42.
Protein kinase casein kinase II (CK2) is increased in response to diverse growth stimuli, as well as being elevated in many human cancers examined. We have demonstrated that CK2 is a key survival factor that protects human colon carcinoma cells from TNF-related apoptosis-inducing ligand (TRAIL)-induced apoptosis. We determined that inhibition of CK2 phosphorylation events by DRB (5,6-dichlorobenzimidazole) resulted in dramatic sensitization of tumor cells to TRAIL-induced apoptosis, in the absence of effects in normal cells. Sensitization was caspase dependent, and independent of regulation via NF-kappaB. Further, inhibition of phosphorylation by CK2 did not modify the expression level of antiapoptotic proteins. Analysis of TRAIL-induced death-inducing signaling complex (DISC) formation demonstrated enhanced formation of the DISC, enhanced cleavage of caspase-8 and cleavage of Bid in the presence of DRB, thereby facilitating the release of proapoptotic factors from the mitochondria with subsequent downregulation of the expression of XIAP and c-IAP1. Further, silencing of CK2alpha in HT29 cells following transfection of CK2alpha shRNA abrogated CK2 kinase activity while simultaneously increasing TRAIL sensitivity. These findings demonstrate that CK2 plays a critical antiapoptotic role by conferring resistance to TRAIL at the level of the DISC.  相似文献   
43.
BACKGROUND: Several models that integrate trauma and emergency general surgery (EGS) have been proposed to provide a diverse and challenging operative practice for trauma surgeons and improve recruitment. In July 2002, our institution established a 24/7 EGS consult service, staffed primarily by critical care/trauma surgeons (CCTS). The objective of this report was to evaluate the impact of this new service on CCTS, general surgeons (GS) and the hospital. METHODS: All admissions to CCTS and GS from July 1, 2000 to June 30, 2003 were reviewed by querying hospital and physician databases for demographics, diagnoses, operative intervention(s), and resource utilization. Data were analyzed using nonparametric methods. RESULTS: [See ]. 9,405 admissions were identified, with GS and EGS admissions increasing over time. In July 2002, EGS became a separate service and captured 26% of GS admissions. Hospital-wide trauma admissions remained stable despite a slight decrease in trauma admissions to CCTS. A decrease in trauma operations by CCTS was offset by an increased EGS operative volume. EGS included "bread and butter" GS procedures including appendectomies and cholecystectomies and complex surgical procedures. EGS patients were often sicker with more than 50% requiring ICU admission compared with GS admissions of which only 10% required ICU care.(Table is included in full-text article.) CONCLUSIONS: Departmental restructuring to include an EGS service: 1) increased CCTS volume despite decreased CCTS trauma admissions and operations; 2) increased elective GS volume; 3) generated increased use of ICU and operating room resources; and 4) demonstrated that CCTS with broad operative GS backgrounds and critical care knowledge can effectively staff an EGS service.  相似文献   
44.
Controversial data are available on the association between the retrovirus-like long-terminal repeat (LTR) DQ-LTR13 and genetic susceptibility to type 1 diabetes and other autoimmune diseases. We analyzed DNA samples from 315 type 1 diabetic patients, 166 autoimmune Addison's disease (AAD) patients, 1,054 healthy subjects, and 144 families of type 1 diabetic offspring. DQ-LTR13 was more frequent among patients than healthy subjects (P(c) < 0.0006), and a preferential transmission of DQB1*0302-LTR13(+) from parents to type 1 diabetic offspring was observed. DQ-LTR13 was in linkage disequilibrium (LD) with DQB1*0302 but not DQB1*0201. The presence of DQ-LTR13 increased the odds ratio of DQB1*0302 2.9- to 3.2-fold for type 1 diabetes and AAD. DRB1*0403 was absent in all of the 169 DRB1*04-positive patients but present in 27% (34 of 127) DRB1*04-positive healthy subjects (P(c) < 0.001). DQ-LTR13 was detected in 1 of 34 (3%) DRB1*0403-positive healthy subjects and 36 of 93 (39%) individuals carrying another DRB1*04 allele (P(c) = 0.002). Multivariate logistic regression analysis revealed that DQ-LTR13 is not independently associated with type 1 diabetes and AAD after correction for DQB1*0302 and DRB1*0403. Conversely, DQB1*0201, DQB1*0302, DRB1*0401, and DRB1*0403 were all significantly associated with disease risk also after correction for DQ-LTR13. We provide conclusive evidence that the genetic association of DQ-LTR13 with type 1 diabetes and AAD is primarily due to a LD with DQB1*0302 and DRB1*0403.  相似文献   
45.
Evidence for active transport of tripeptides by hamster jejunum in vitro.   总被引:4,自引:0,他引:4  
1. This paper describes the uptake by rings of everted hamster jejunum in vitro of three peptides with structural features making them resistant to hydrolysis, glycylsarcosylsarcosine, glycylsarcosylsarcosylsarcosine and beta-alanylglycylglycine. 2. Glycylsarcosylsarcosine was taken up by a saturable mechanism and accumulated intact in the intracellular compartment of the intestinal wall, apparently against an electrochemical gradient. Its uptake was reduced by Na+-replacement, anoxia and metabolic inhibitors. It was concluded that uptake of this peptide was the result of Na+-dependent active transport. 3. Glycylsarcosylsarcosylsarcosine was very poorly taken up and its uptake did not appear to be the result of active transport. 4. Beta-Alanylglycylglycine appeared intact in the intracellular compartment of the intestinal wall on a substantial scale though it was not concentrated. No satisfactory evidence of uptake by a saturable mechanism was obtained. Uptake was, however, inhibited by anoxia, 2,4-dinitrophenol and Na+-replacement. Reasons are given for supposing that uptake of this peptide may be the result of Na+-dependent active transport by the same carrier as that utilized by glycylsarcosylsarcosine. 5. The results suggest that provided that they escape brush-border hydrolysis, tripeptides, like dipeptides, are actively transported into the absorptive cells of the intestinal mucosa, but that the ability of these cells to take up peptides by an active mechanism is unlikely to extend to tetrapeptides.  相似文献   
46.
A wavelet-based method is presented for oxygen saturation measurement using photoplethysmogram signals from a standard pulse oximeter device. The transform moduli of both red and infrared signals are used to derive a novel wavelet ratio surface. Projection of the pulse component onto this surface allows optimal derivation of oxygen saturation.  相似文献   
47.
Pulmonary MnSOD is nitrated following hepatic ischemia-reperfusion   总被引:5,自引:0,他引:5  
BACKGROUND: Ischemia-reperfusion (I/R) of remote organs is a common cause of lung injury. We observed that lung injury after partial hepatic I/R in mice coincides with the appearance of 3-nitrotyrosine (NT) in the lung tissue, a marker of peroxynitrite involvement and oxidant stress. Peroxynitrite can cause mitochondrial dysfunction by inactivation of manganese superoxide dismutase (MnSOD), the major antioxidant enzyme in mitochondria. Our aims were to examine whether pulmonary MnSOD is a target of nitration following hepatic I/R and whether nitrated MnSOD (N-MnSOD) correlates with acute lung injury. METHODS: Five 20-25-g male C57BL/6 mice underwent laparotomy, and atraumatic occlusion of the portal and arterial blood supply to the upper three lobes of the liver for 90 min. This warm ischemic period was followed by 4 h of reperfusion, and the animals were then euthanized. Lung injury was assessed by LDH and protein levels in bronchoalveolar lavage (BAL) fluid. Pulmonary MnSOD activity in pulmonary homogenates was measured by the cytochrome c reduction method. The presence of N-MnSOD was determined by immunoprecipitation (IP) and Western Blot analysis. Controls (N = 5) underwent sham operation. RESULTS: Elevated plasma transaminases confirmed hepatic injury. Lung injury was demonstrated by elevation in BAL protein and LDH levels (495.7 (48.4) versus 644.9 (37.3) [p < 0.05] and 56.5 (11.8) versus 345.2 (80) [p < 0.01], respectively). Immunoprecipitation and Western blot demonstrated N-MnSOD in the lung tissue of I/R animals but not controls. MnSOD activity decreased following I/R (8.1 (0.7) versus 10.8 (0.3) [p < 0.05]). CONCLUSIONS: Pulmonary MnSOD is both nitrated and inactivated following hepatic I/R and is associated with acute lung injury. These findings suggest that MnSOD incapacitance may contribute to I/R-induced lung injury and provide a therapeutic target in attenuating multisystem injury following hepatic I/R.  相似文献   
48.
BACKGROUND: Critically ill trauma patients are often too unstable for safe transfer to the operating room. Damage control laparotomy patients frequently require early reoperation and have a reported mortality of 50-60%. As a result, many of these patients must undergo laparotomy in the intensive care unit. We hypothesized that patients undergoing bedside laparotomy (BSL) and managed with the abdomen left open would have an unacceptably high mortality or intra-abdominal complications. METHODS: We performed a retrospective chart review of our Trauma Registry. Of the 11,096 consecutive trauma admissions from March 1, 1996 to May 20, 2000, 75 patients underwent 95 BSL. Patients were stratified according to injury severity score (ISS), base deficit (BD), lactic acid (LA), total transfusion (TRBC) requirements, indication for BSL, mechanism of injury, infectious complications (intra-abdominal abscess (IAA), fistula), and length of hospital stay. RESULTS: Seventy-five patients underwent 95 BSL. Mean ISS was 50.6 +/- 18.9, mean BD was -11.9 (+/- 5), and the mean LA was 5 +/- 5 for the study group. The TRBC for the group was 43.7 +/- 42.6 units. Indications for the 95 BSL were (1) abdominal compartment syndrome (n = 47, 49.5%); (2) suspected intra-abdominal infection (n = 18, 19.0%); (3) washout/pack removal (n = 14, 14.7%); (4) washout with fascial closure (n = 12, 12.6%); and (5) other (n = 4, 4.2%). Twenty-nine of 75 patients (39.2%; ISS 52.3 +/- 18.8) died within 72 h of operation. Of the 46 remaining patients, an additional eight died 72 h or more after operation, for a late mortality rate of 17.4% and a total mortality rate of 49%. None of these deaths were attributable to either the operation or to post-operative IAA or fistula formation; all late deaths were secondary to multiple organ failure. Intra-abdominal abscesses developed in three of 46 patients (6.5%), each of whom had a TRBC of >100 units (mean, 160 units). Five of 46 patients (10.9%) developed enterocutaneous fistulae. None of these eight patients died. Thirty-eight of 75 patients (50.7%) survived to discharge, with a mean ISS of 40 (+/- 11.9). CONCLUSIONS: Despite the high acuity of the population undergoing BSL, 50.7% of patients survived. Moreover, during BSL, IAA and fistula formation occurred at low rates.  相似文献   
49.
There are many reasons why patients need a catheter, and the length of time one is needed varies, depending on the condition and how well the patient is. This review looks at the range of catheters available and the advantages and disadvantages for individual patients of the different sorts.  相似文献   
50.
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