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31.
Aortic arch replacement with proximal first technique.   总被引:2,自引:0,他引:2  
BACKGROUND: Deep hypothermic circulatory arrest (DHCA) without retrograde cerebral perfusion (RCP) has a strict time limit. We modified a surgical technique for anastomosis to shorten the period of DHCA and unilateral cerebral perfusion (UCP). METHODS: Between March 1993 and August 2001, retrospective analysis was done on 23 consecutive patients, who underwent aortic arch replacement with branches. The patients were divided into two groups: DHCA group and UCP group. The DHCA group, in which DHCA alone and without additional cerebral perfusion was performed, comprised of nine patients. Proximal aortic anastomosis was performed first during systemic cooling; then both the brachiocephalic artery and left carotid artery were reconstructed with the branches of the artificial graft during circulatory arrest; thereafter, cerebral and coronary perfusions were resumed. The UCP group, in which DHCA was not used but right hemisphere perfusion during deep hypothermia was performed when the origin of brachiocephalic artery was safely clamped, consisted of 14 patients. RESULTS: Mean time of DHCA was 18.8+/-4.2 minutes and that of right hemisphere perfusion time was 11.0+/-3.8 minutes, respectively. Twenty-one patients survived the surgery (91.3%), and two (8.7%) died during hospitalization. Transient cerebral complication occurred in four patients in the DHCA group and all recovered. Logistic regression analysis revealed that DHCA was the only parameter to significantly influence temporary neurological dysfunction. There was no other significant difference between the two groups. CONCLUSION: With our modified and simple surgical technique for aortic arch repair, we were able to successfully shorten the DHCA time and right hemisphere perfusion time. However, because DHCA was the only parameter to significantly influence temporary neurological dysfunction, some form of continuous cerebral perfusion at deep hypothermia may be a safer method to preserve cerebral function.  相似文献   
32.
An attempt was made to isolate the active component which exhibits an improving effect on renal function from Salviae Miltiorrhazae Radix (Chinese crude drug). Systematic isolation from aqueous extract of Salviae Miltiorrhizae Radix was carried out, and Compound 1 was found to be more effective than any of the other constituents in improving renal functional parameters; that is, a marked reduction of glomerular filtration rate following adenine ingestion was improved by administration of this substance. The renal plasma flow and renal blood flow were also increased in renal failure rats. On the basis of chemical and spectroscopic data, Compound 1 was shown to be identical with magnesium lithospermate B.  相似文献   
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Combined measurement of serum prostate-specific antigen (PA) and prostatic acid phosphatase (PAP) was performed in 235 patients with various urologic diseases including 55 patients with prostatic cancer. A PA level of over 24.7 ng/ml and a PAP level of over 3.1 ng/ml were considered to be positive. The positive rate of PA was 57% in the patients with untreated prostatic cancer and 3% in the patients without prostatic cancer. The positive rate of PAP was 52% in the patients with untreated prostatic cancer and 1% in the patients without prostatic cancer. PA and PAP were considered to be equally sensitive and specific serum markers of prostatic cancer. However, the positive rate increased to 65% without increasing the false positive rate when the PA and PAP were both measured simultaneously. The combined assay of PA and PAP is recommended for screening prostatic cancer. The cross-over titer of PA and gamma-Sm using standard samples in each kit revealed linearity, which suggested that PA and gamma-Sm possess the same antigenicity.  相似文献   
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OBJECTIVE. The purpose of this study was to investigate the feasibility of using a holmium:yttrium-aluminum-garnet laser to permanently occlude the cystic duct in order to isolate the gallbladder from the biliary-enteric circulation and prevent gallstone formation. MATERIALS AND METHODS. To determine the optimal laser parameters (power and pulsing rate) for cystic duct thermocoagulation, 20 freshly excised porcine gallbladders with intact cystic ducts underwent low-energy (0.075-0.085 J/pulse) or high-energy (0.20-0.25 J/pulse) thermocoagulation. Histopathologic examination was done to determine the extent of cystic duct injury. After in vitro experiments, percutaneous transcholecystic laser thermocoagulation of the cystic duct was performed on 23 anesthetized domestic pigs (four controls). Cholangiograms immediately after laser thermocoagulation were obtained to assess cystic duct occlusion. Animals were sacrificed for histopathologic correlation immediately after laser thermocoagulation (n = 4), 72 hr later (n = 4), and 6 weeks later (n = 15). RESULTS. In the in vitro studies, all 10 cystic ducts in the high-energy group were occluded, while only four in the low-energy group were occluded. At histology, all cases in both groups showed circumferential injury to the cystic duct wall without injury to the cystic artery or vein. In the in vitro experiments, the cystic duct was successfully cannulated in 21 (91%) of 23 animals. Cholangiography after thermocoagulation showed occlusion of the cystic duct in 16 (84%) of 19 cases. Immediately after laser thermocoagulation, the cystic duct mucosa was circumferentially destroyed, whereas after 72 hr necrosis of the cystic duct wall and periductal tissues had occurred. By 6 weeks, all pigs had complete cystic duct fibrosis without injury to the common bile duct. CONCLUSION. Holmium:yttrium-aluminum-garnet laser thermocoagulation of the cystic duct can be performed easily, results in immediate cystic duct occlusion, and leads to permanent fibrous ductal obliteration by 6 weeks.  相似文献   
37.
Forty-nine pathologically proven gallbladder lesions were evaluated in 45 patients using dynamic MRI with a spoiled gradient pulse sequence (SPGR), to access the ability of this technique to differentiate benign from malignant gallbladder lesions. The studies were reviewed retrospectively. Signal intensity of the lesions were measured. Twenty-one malignant and 28 benign lesions were classified into three categories: polypoid, diffuse wall thickening, and exophytic. Early and delayed enhancement patterns were evaluated. For the polypoid masses, malignant lesions (n = 9) demonstrated early and prolonged enhancements, whereas benign lesions (n = 14) had early enhancement with subsequent washout (P < .05). For diffuse gallbladder wall thickening, malignant lesions (n = 6) demonstrated early and prolonged enhancement and benign lesions (n = 14) showed relatively slow, prolonged enhancement (P < .05). The exophytic masses (n = 6) all were malignant and demonstrated early and prolonged enhancement. Dynamic MRI can help differentiate benign from malignant gallbladder lesions.  相似文献   
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Five latissimus dorsi musculocutaneous flaps (LD flap) were used for reconstruction with prostheses after resection of tumors between 1984 and 1991 in our hospital. Bony structures were reconstructed with prostheses and in three cases autoclaved autobone grafts were also needed. The prostheses and adjacent grafts were then wrapped by the LD flaps. Tumor sites included one humerus, two thighs, and two knees. All but one case healed primarily. The sole case of infection was successfully treated with debridement and irrigation. Due to the LD flaps' plentiful blood supply, we believe infection of the prosthetics can be avoided and good clinical results can be achieved using the flap with autoclaved autograft prosthetic composite reconstruction. © 1994 Wiley-Liss, Inc.  相似文献   
40.
Oligonol is produced from the oligomerization of polyphenols (typically proanthocyanidin from a variety of fruits such as lychees, grapes, apples, persimmons, etc.) and contains catechin-type monomers and oligomers of proanthocyanidins. The ability of Oligonol to affect infection-dependent eye inflammation, locomotion and longevity in senescence-accelerated prone mice (SAMP8) (a model of senescence acceleration and geriatric disorders with increased oxidative stress and neuronal deficit) was investigated. Oligonol (60mg/kg) significantly modulated the extent of inflammation scores in the eye of SAMP8 mice. Examination of the mice indicated infection with mouse hepatitis virus and pinworm (Syphacia obvelata) in both males and females and with the intestinal protozoa (trichomonad) in males. A comparison of the two groups (using log-rank test) and the difference in the mean life span between groups (using Student's t-test) indicated significant differences in survival (p=0.043) and the mean life span (p=0.033) in male SAMP8 mice. Oligonol increased the mean life span and this was statistically significant. In the open-field locomotive test, the 7-week-old SAMP8 mice crossed more than 40 partitioned lines in 1min. At 48-week-old control untreated male SAMP8 crossed 2 lines. The Oligonol-treated 48-week-old male SAMP8 mice crossed 17 lines however. The improved locomotive activity was statistically significant even after 36weeks in the Oligonol-treated male SAMP8 but this was not the case throughout the time course of the study in the Oligonol-treated female SAMP8. Thus Oligonol treatment to SAMP8 mice modulated the severity of infection-dependent inflammation, prolonged life-span and significantly improved locomotive activity indicating potential benefit to aging-associated diseases such as Alzheimer's or Parkinson's diseases. This presents potential for further research to define infection-dependent inflammation associated with degenerative conditions and the molecular mechanism of dietary antioxidant protection.  相似文献   
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