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131.
We elucidate the roles of various protein kinases involved in complement 5a (C5a)-induced cell migration. Results showed that extracellular signal-regulated kinase1/2 (ERK1/2), p38 mitogen-activated protein kinase (p38 MAPK) and phosphatidylinositol 3-kinase (P13K) were necessary for C5a-induced migration, whereas protein kinase C and c-Jun N-terminal kinase (JNK) were nonessential. C5a-induced migration was also suppresses by phospholipase C (PLC) inhibitor U73122 and pertussis toxin (PTX). We found that C5a-induced, time-dependent (1) ERK1/2 phosphorylation was markedly diminished by PTX, U73122, P13K inhibitors wortmannin and LY294002 and ERK1/2 inhibitor PD98059; (2) Akt phosphorylation was also attenuated by the above inhibitors except PD98059; (3) p38 MAPK phosphorylation was only affected by PTX. Furthermore, C5a also stimulated PLCbeta(2) membrane translocation in a time-dependent manner that occurred early prior to Akt phosphorylation and could be abolished only by PTX and U73122. These results suggest that C5a, through the activation of PTX-sensitive G protein, to differentially stimulate ERK1/2 and p38 MAPK phosphorylation and evoke cell migration. That is, ERK1/2 but not p38 MAPK phosphorylation is down stream of P13K/Akt and modulated by PLC. Additionally, beta(2) isoform may be one of the participates in C5a signal and acts more upstream of P13K/Akt.  相似文献   
132.
The importance of the stratum corneum and its barrier function for infants, especially for newborns, is clinically evident. Research regarding the maturation of the stratum corneum in neonates, i.e. when full barrier function is obtained, has produced varying results. Based on transepidermal water loss and percutaneous absorption studies, term infants seem to possess stratum corneum with adult barrier properties. Additionally, postnatal life is thought to accelerate stratum corneum maturation, so that even preterm infants have barrier function similar to term infants at 2-3 weeks of gestational age. However, a look at other parameters, such as skin thickness, skin pH and stratum corneum hydration, shows that neonatal skin is always adjusting to the extrauterine environment in contrast to the steady state of adult skin. This suggests that barrier stabilization may be dependent on achieving a balance between different parameters. However, it is still in question, which parameters, what balance and what timing. This paper provides an up-to-date overview on the neonatal skin barrier based on the review of current literature.  相似文献   
133.
Our previous reports have indicated that high risk human papillomarvirus (HPV) 16/18 were much more frequently detected in lung tumors of female patients as compared to that of male patients and HPV 16/18 in lung tumors were evolutionally correlated with those in blood circulation. In the other hand, it is well known that HPV 6/11 are frequently associated with upper aerodigestive and respiratory diseases. HPV 6/11 DNA were detected in lung tumors by nested PCR and in situ hybridization to investigate if any difference in prevalent types of HPV exists between genders. Our data showed that HPV 6 infection was detected in 28.4% (40 of 141) lung tumors, which was significantly higher than that in non-cancer controls (1.7%, 1 of 60; P < 0.0001), however, such high prevalence was not observed for HPV 11. Among studied clinico-pathological parameters, HPV 6 infection was significantly related with gender (P = 0.002) and smoking status (P = 0.014). After being stratified by gender and smoking status, HPV 6 infection rate in lung tumors of non-smoking male patients was much higher than that in non-smoking female patients (33.3% versus 11.1%; P = 0.023), but no difference between smoking and non-smoking male patients (38.1% versus 33.3%). With adjustments for age, tumor type, and tumor stage, smoking male lung cancer patients had a much higher OR value (OR, 7.35; 95%CI, 2.11-25.58) for HPV 6 infection compared with 3.93 (95% CI, 1.17-13.12) of non-smoking male patients. Moreover, a higher prevalence of HPV 6 was detected in lung tumors of smoking male patients with early tumor stage than those with advanced stages (P = 0.008), but not in non-smoking male and female patients. A higher prevalence of HPV 6 in male lung cancer patients, as compared with female lung cancer patients, indicating not only different HPV infection routes for different genders, but also that HPV 6 infections may act as a prospective early risk marker of lung cancer for smoking male patients in Taiwan.  相似文献   
134.
Paclitaxel has significant antitumor activity in several human tumors, including Kaposis sarcoma (KS). Human herpesvirus 8 (HHV-8) is implicated in all forms of Kaposis sarcoma, primary effusion lymphoma (PEL), and multicentric Castlemans disease (MCD), indicating that it is a DNA tumor virus. Since it is difficult to culture cell lines derived from KS patients, we used a cell line derived from PEL (BCBL-1) to investigate whether oxidative stress is involved in the cytotoxicity of paclitaxel on the HHV-8-related tumors. We found that the generation of reactive oxygen species (ROS) in the BCBL-1 cells was increased by paclitaxel treatment, and the increase in ROS production was suppressed by antioxidants, including catalase and ascorbic acid. Moreover, ascorbic acid also attenuated the cytotoxicity induced by paclitaxel. Upon paclitaxel treatment, caspase-2, caspase-3, and caspase-8 were activated in BCBL-1 cells. Cotreatment with antioxidants did not affect caspase-2, caspase-3 or caspase-8 activation. Paclitaxel-induced apoptosis was also accompanied by an increase in the protein levels of Bax, and this effect was attenuated by antioxidants. Paclitaxel slightly decreased the expression of Bcl-2 protein, but antioxidants induced Bcl-2 protein. These results suggest that oxidative stress is only partially involved in the cytotoxicity of paclitaxel in BCBL-1 cells, and that paclitaxel-induced apoptosis of BCBL-1 cells is primarily mediated by the caspase activation pathway.  相似文献   
135.
We have cloned, expressed and characterized catfish alphaB-crystallin (FalphaB). Genomic sequence comparison has revealed conservation of intron splicing sites and coding regions, however, the two intron sequences, 5'- and 3'-untranslated regions of FalphaB gene are shorter than those reported for other vertebrates. In contrast to mammalian homologues with a subunit association ratio (alphaA-crystallin/alphaB-crystallin) of 3:1, alpha-crystallin from catfish lens showed a ratio of 19:1. The biophysical properties and chaperone-like activity of recombinant FalphaB and porcine alphaB-crystallin (PalphaB) were studied and compared by heat denaturation, circular dichroism, intrinsic and dye-binding fluorescence, gel-filtration, and analytical ultracentrifugation. FalphaB shows 50% precipitation occurring at 72 degrees C that is higher than PalphaB at 66 degrees C. Even though FalphaB also possesses more surface hydrophilic regions than PalphaB, FalphaB still possesses higher chaperone activity to prevent aggregation of alcohol dehydrogenase at 60 degrees C. The molecular mass of FalphaB showed a smaller size (450 kDa) than PalphaB (550 kDa), which is also confirmed by analytical ultracentrifugation. In addition, FalphaB possesses better refolding potential after preheating treatment than PalphaB. FalphaB also exhibits higher chaperone-like activity than PalphaB to prevent insulin aggregation induced by dithiothreitol. In contrast to the prevalent notion that fish crystallins generally denature easily, FalphaB with chaperone-like activity appears to be more stable than mammalian homologues towards thermal and chemical denaturation.  相似文献   
136.
137.
OBJECTIVE: To report a case of successful pregnancy after laparoscopic bipolar coagulation of uterine vessels (LBCUV). DESIGN: Case report. SETTING: University-affiliated tertiary referral center. PATIENT(S): One woman, treated with LBCUV for symptomatic fibroids, who subsequently had a successful pregnancy. INTERVENTION(S): Laparoscopic bipolar coagulation of uterine arteries and anastomotic sites of uterine arteries with ovarian arteries. MAIN OUTCOME MEASURE(S): Patient evaluation by physical and ultrasound examinations. RESULT(S): Complete resolution of menorrhagia and dysmenorrhea was found after LBCUV. Reduction in fibroid size was seen by ultrasound. Two months later, the patient conceived a singleton pregnancy without the use of assisted reproductive technologies. The woman delivered by cesarean section. Neither myoma recurrence nor abnormality in uterine function was observed. CONCLUSION(S): Although fecundity- and pregnancy-related complications after LBCUV for managing uterine fibroids are still unclear, this first case report of successful pregnancy after LBCUV is promising. LBCUV might be a safe and effective alternative to myomectomy and hysterectomy.  相似文献   
138.
The aim of the study was to define the factors that may predict the outcomes of radiofrequency ablation from the right ventricular outflow tract (RVOT) in patients with idiopathic VT with a QRS morphology of LBBB. Endocardial mapping and RF ablation from the RVOT were performed in 35 patients (14 men, mean age 41 +/- 14 years), and VT was successfully ablated in 30 patients. There was no significant difference with regard to clinical characteristics and electrophysiological findings between patients with successful and failed ablation. The VTs with successful ablation showed an rS (n = 16) or QS (n = 14) pattern in lead V1, and all five VTs with failed ablation showed an rS pattern in lead V1. Although the absence of an R wave in lead V1 did not differ between patients with successful and failed ablation (P = 0.13), the absence of an R wave in lead V1 predicted VT successfully ablated from the RVOT (positive predictive value 100%; negative predictive value 24%). The VTs with successful ablation had a median precordial transitional zone at lead V4 (range V3-V6), whereas all five VTs with failed ablation had precordial transition zones at lead V3 (P = 0.004). Furthermore, a presence of an R wave in lead V1 associated with a precordial transition zone at lead V3 predicted VT not successfully ablated from the RVOT (positive predictive value 100%; negative predictive value 100%). In conclusion, some VTs with LBBB and inferior or normal axis cannot be ablated from the RVOT. The presence of an R wave in lead V1 associated with a precordial transition zone at lead V3 suggest that some VTs may not arise from the RVOT.  相似文献   
139.
Higher pretreatment serum hepatocyte growth factor (HGF) levels were observed in patients with multiple myeloma and Hodgkin's disease, but not in those with non-Hodgkin's lymphoma (NHL). We examined patients' serum levels at diagnosis using enzyme-linked immunosorbent assay and histological expression of HGF in pathological specimens of lymphoma, in relation to clinical features. The subjects were 77 NHL patients and 40 healthy controls. The serum levels of HGF in NHL patients at diagnosis were significantly higher than those in healthy controls (median 1019 vs. 689 pg/mL, P < 0.001). At diagnosis, patients with more than two sites of extranodal involvement (P = 0.001), higher scores of international prognostic index (P = 0.015), and advanced Ann Arbor stage (P = 0.023) had a higher level of serum HGF. Although the association of pretreatment serum HGF level and survival was not significant, a correlation of serial change of serum HGF levels with treatment response was found in limited cases. Furthermore, HGF expression of lymphoma tissues was shown in 18 of 24 (75%) different NHL subtypes, including most of the diffuse large B cell lymphoma (12 of 15, 80%). In conclusion, our study showed higher pretreatment serum HGF levels in NHL patients, which was related to clinical features; and the serial change of HGF seemed to parallel the treatment response. The pathogenic role of HGF in NHL patients was further highlighted by a modest expression of HGF in most of the diffuse large B cell lymphoma.  相似文献   
140.
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