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81.
Objective: To compare the pharmacokinetics and pharmacodynamics of 100 mg/d, 200 mg/d, and 400 mg/d (200 mg two times per day) of P administered vaginally for 14 days to estrogen-primed postmenopausal women.Design: Randomized, open-label, three-way crossover study.Setting: Two university-based investigative sites.Patient(s): Twenty healthy postmenopausal women with histologically normal endometria.Intervention(s): Oral 17,β-E2 was given each day of a 28-day cycle; a P vaginal suppository was inserted daily according to the randomization schedule during days 15–28 of each cycle; blood samples were collected; an endometrial biopsy was obtained on day 25; and patients were crossed over to the next treatment cycle after a washout period of at least 30 days.Main Outcome Measure(s): Mean P blood levels, endometrial dating/conversion.Result(s): There was good vaginal absorption of P for all dosages. Endometrial conversion occurred in all 200- and 400-mg/d P-dosed cycles, whereas the 100-mg/d dosage failed to convert primed endometria consistently. There also was a significantly increased tendency for earlier bleeding and spotting with the 100-mg/d dosage.Conclusion(s): Both the 200- and 400-mg/d dosage regimens consistently convert an estrogen-primed endometrium, and yield appropriate endometrial dating and bleeding patterns. However, the 400-mg/d dosage attains the highest sustained blood levels and may be the best dosage regimen for further study.  相似文献   
82.
Pelvic ultrasonography in normal girls and in girls with pubertal precocity   总被引:6,自引:0,他引:6  
This prospective study sought to evaluate the role of pelvic ultrasonography in differentiating between various types of pubertal precocity. A control group of 117 normal girls (aged 1.1-15.6) was studied and compared with 87 girls with premature sexual maturation (aged 1.1-9.2y). Of these patients 19 had central precocious puberty (CPP), 48 had isolated premature thelarche (IPT) and 20 had premature adrenarche (IPA) Pelvic ultrasound variables evaluated were: (i) uterus: longitudinal diameter (uterine length), cross-sectional area (CSA) and fundo-cervical ratio; and (ii) ovaries: volume and morphology. Ovarian morphology was subdivided in 6 different appearances: solid, microcystic, paucicystic, multicystic, macrocystic, and major isolated cyst. In normal control girls, uterine length and CSA increased with age, although no cut-off values could be defined between different age ranges, and they were correlated with breast stage; fundo-cervical ratio was stable through childhood and increased after age 9. Ovarian volume was significantly greater in pubertal girls with breast stage 2 than in those with only pubic and/or axillary hair. There was a clear predominance of solid ovarian appearances in the age range 2-7, with the multicystic appearance being seen only after age 7, a minority being macrocystic. After age 10 all the different patterns were observed, and after age 13 the frequency of a macrocystic pattern increased. Significantly more mature ovarian appearances were observed in subjects with breast development compared with those without, independently of the presence of pubic hair. Patients with IPT had no significant differences in pelvic ultrasound measurements when compared with age-matched controls. All the different morphological ovarian appearances were observed in IPT, in contrast to age-matched controls, where only the less mature patterns (solid, micro- and paucicystic) were seen. Patients with CPP had significantly more mature patterns of ovarian morphology compared with age-matched controls, but did not differ from pubertal pre-menarcheal controls. Those patients with IPA differed from age-matched controls only in having significantly greater uterine length and CSA. Comparison of the pelvic ultrasound parameters between patient groups (IPT, CPP, IPA) and age-matched controls revealed significantly higher values in CPP for uterine length, uterine CSA and ovarian volume. Ovarian volume was also greater in IPT than in IPA. Ovarian morphology was significantly different in patients (IPT, CPP, IPA) compared with age-matched controls, but none of the ovarian morphological appearances was exclusive to a single condition. In conclusion: (i) pelvic ultrasound parameters increase progressively from birth to maturity, but no clear cut-off values can be established between age ranges; (ii) pelvic ultrasound variables reach adult values during puberty, with differences in the timing that may reflect geographical variations; (iii) the multicystic ovarian appearance occurs just before the onset of puberty; (iv) pelvic ultrasonography cannot always differentiate clearly between different disturbances of puberty and therefore cannot supersede other observations and investigations in the evaluation of pubertal disorders; and (v) in this study we propose a more detailed pelvic ultrasound terminology that can avoid apparent confusion in defining ovarian ultrasound appearance.  相似文献   
83.
BACKGROUND: This study examined the hypothesis that elderly trauma patients on warfarin before injury will have increased morbidity and mortality compared with elderly trauma patients not on warfarin. METHODS: From 1993 to 1995, trauma patients were grouped by age and presence or absence of warfarin use before injury. Groups were analyzed with respect to Injury Severity Score, Trauma Registry and Injury Severity Score, Glasgow Coma Scale score, Intensive Care Unit days, hospital days, units of blood transfused, and mortality rates. Statistical analysis was completed by using the Student's t test. RESULTS: Records of 61 patients administered warfarin and 800 patients not administered warfarin were available for analysis. There were no statistically significant differences between patients on prehospital warfarin and those not on prehospital warfarin. CONCLUSION: This study indicates that elderly trauma patients on warfarin before injury do not have increased morbidity and mortality compared with elderly trauma patients not on warfarin.  相似文献   
84.
Multiple factors contribute to the development of posttraumatic empyema. These factors include the conditions under which the tube is inserted (emergent or urgent), the mechanism of injury, retained hemothorax, and ventilator care. The incidence of empyema in placebo groups ranges between 0 and 18%. The administration of antibiotics for longer than 24 hours did not seem to significantly reduce this risk compared with a shorter duration, although the numbers in each series were small. Most reports found a significant reduction in pneumonitis when patients received prolonged prophylactic antibiotics. This use of antibiotics might possibly be better described as presumptive therapy rather than prophylactic.  相似文献   
85.
BACKGROUND: Recently we demonstrated an increased 2,3-diphosphoglycerate (2,3-DPG) erythrocyte concentration in rat pups subjected to nucleotide-enriched artificial feeding. DESIGN: The present study was carried out to test the hypothesis that a possible increase in 2,3-DPG concentration can also be obtained in human neonates who are fed nucleotide-enriched formula. Preterm neonates born or referred to the neonatal intensive care unit of the G. Gaslini Hospital, Genoa University, with a gestational age >30 weeks and <37 weeks were enrolled in our randomized trial. Recruitment took place within 48-72 hours from birth. Only newborns of mothers deciding not to breast-feed were eligible to be randomized for the supplemented group (FN) or non-supplemented group (RF). Breast-fed newborns were considered the control group (C). The study window (for supplementation and blood samples) was restricted to the first two weeks following birth (from the 2nd (t1) to the 16th (t2) day of life). At the end of our study, only 21 neonates were eligible for statistical analysis. RESULTS: The stimulating action of dietary nucleotides on 2,3-DPG concentration failed to be demonstrated; increases in 2,3-DPG concentration that were observed in newborns fed with nucleotide supplemented formula (FN) were comparable to those observed in newborns fed with regular formula (RF) and breast-fed newborns. CONCLUSIONS: The EC recommendation for the amount of nucleotides allowed in formula milk does not seem to be high enough to have positive effects on 2,3-DPG synthesis. Whether this possible 'pharmacological' effect can be achieved by a higher intake of ingested nucleotides and/or a change in the proportions of single nucleotides contained in milk formulas remain interesting end points to be elucidated.  相似文献   
86.
Nocturnal frontal lobe epilepsy (NFLE) has become clinically relevant in recent years. NFLE represents a spectrum of clinical manifestations, ranging from brief, stereotyped, sudden arousals, often recurring several times per night, sometimes with a quasi-periodic pattern, to more complex dystonic-dyskinetic seizures and to prolonged "somnambulic" behaviour. Episodes of increasing intensity have been labelled as paroxysmal arousal (PA), nocturnal paroxysmal dystonia (NPD) and episodic nocturnal wandering (ENW). NFLE affects both sexes with a higher prevalence for men, is frequently cryptogenetic and displays a strong familial trait for parasomnias and epilepsy (NFLE). Seizures appear more frequently between 14 and 20 years of age, but can affect any age and tend to increase in frequency during life. Interictal and ictal scalp electroencephalography (EEG) are often normal, the use of sphenoidal leads may be helpful. Carbamazepine taken at night is often effective at low doses, but a third of the patients are resistant to anti-epileptic drugs (AED) treatment. A familial form, characterized by an autosomal dominant transmission, has also been described. Autosomal dominant nocturnal frontal lobe epilepsy is a genetic variant of NFLE, in itself both clinically and biologically heterogeneous. NFLE should be suspected in the presence of frequent stereotyped paroxysmal nocturnal motor events arising or persisting into adulthood. Videopolysomnography is mandatory to confirm the diagnosis.  相似文献   
87.
PURPOSE: Incapacitating symptom burden in cancer patients contributes to poor quality of life (QOL) and can influence treatment outcomes because of poor tolerance to therapy. In this study, the role of circulating cytokines in the production symptoms in cancer patients is evaluated. EXPERIMENTAL DESIGN: Eighty patients with metastatic colorectal cancer with either normal (group I, n = 40) or dampened (group II, n = 40) 24-hour rest/activity patterns measured by actigraphy were identified. Actigraphy patterns were correlated with QOL indices, serum cortisol obtained at 8:00 a.m. and 4:00 p.m. and with serum levels of transforming growth factor-alpha, tumor necrosis factor-alpha, and interleukin 6 (IL-6) obtained at 8:00 a.m. and analyzed in duplicate by ELISA. Cytokine levels and survival were also correlated. RESULTS: Group II patients had significantly higher pre treatment levels of all three cytokines, displayed significantly poorer emotional and social functioning, had higher fatigue, more appetite loss, and poorer performance status compared with group I patients. Transforming growth factor-alpha (TGF-alpha) and IL-6 were significantly increased in the patients with WHO performance status >1 and in those with appetite loss. Fatigue was significantly associated with elevated TGF-alpha only. IL-6 was increased in those patients with extensive liver involvement and multiple organ replacement, and it was significantly correlated with dampened cortisol rhythm. In a multivariate analysis, IL-6 was correlated with poor treatment outcome. CONCLUSIONS: Significant correlations were found between serum levels of TGF-alpha and IL-6, circadian patterns in wrist activity and serum cortisol and tumor-related symptoms in patients with metastatic colorectal cancer. These data support the hypothesis that some cancer patient's symptoms of fatigue, poor QOL, and treatment outcome are related to tumor or host generated cytokines and could reflect cytokine effects on the circadian timing system. This interplay between cytokine signaling pathways, the hypothalamic-pituitary-adrenal axis, the autonomic nervous system, and efferent pathways of the suprachiasmatic nucleus that control circadian physiology, opens the way to new rational interventions for symptom management in cancer patients.  相似文献   
88.
PURPOSE: The extent of venous thromboembolism (VTE) associated with central vein catheters (CVC) in cancer patients remains unclear. The aim of this study was to evaluate the efficacy and safety of the low molecular weight heparin, enoxaparin, in the prevention of VTE. PATIENTS AND METHODS: In a multicenter, double-blind study, consecutive cancer patients scheduled for CVC insertion were randomly assigned to receive either subcutaneous enoxaparin 40 mg once a day or placebo. Treatment was started 2 hours before CVC insertion and continued for 6 weeks. The primary end points of the study were deep vein thrombosis (DVT), confirmed by venography of the CVC limb performed 6 weeks after randomization, or clinically overt pulmonary embolism, confirmed by objective testing during the study drug administration. Patients were assessed for bleeding complications. RESULTS: Three hundred eighty-five patients were randomized, of which 321 (83.4%) underwent venography. A venography was adequate for adjudication in 155 patients in each treatment group. A DVT was observed in 22 patients (14.1%) treated with enoxaparin and in 28 patients (18.0%) treated with placebo, corresponding to a relative risk of 0.78 (95% CI, 0.47 to 1.31). No major bleeding occurred. Five patients (2.6%) in the enoxaparin group and two patients (1.0%) in the placebo group died during the treatment period. CONCLUSION: In this study, no difference in the rate of CVC-related VTE was detected between patients receiving enoxaparin and patients receiving placebo. The dose of enoxaparin used in this study proved to be safe. Clinical trials evaluating higher enoxaparin doses could optimize the efficacy of this agent for this indication.  相似文献   
89.
OBJECTIVES: Intestinal alkaline sphingomyelinase, by exerting a major role in dietary sphingomyelin digestion, is responsible for the generation of messengers able to trigger the rapid turnover and apoptosis in intestinal epithelial cells. Markedly reduced mucosal alkaline sphingomyelinase activity has been associated with human colorectal neoplasms. The aim of this study was to analyze the alkaline sphingomyelinase activity in feces from healthy subjects and colorectal adenocarcinoma patients and to correlate it with the enzyme activity in intestinal tissues. MATERIALS AND METHODS: The enzyme activity was measured both in the intestinal samples from 12 healthy controls and 51 patients with colorectal adenocarcinoma (tumoral and paratumoral tissue) and in the fecal samples of 34 healthy subjects and 29 patients with adenocarcinoma. The relation between sphingomyelinase activity and Dukes' stage, cell differentiation degree, age, and gender was also analyzed. RESULTS: Alkaline sphingomyelinase was significantly decreased (P < 0.001; mean reduction >90%) in tumoral intestinal mucosa of patients compared with controls independently of Dukes' stage and tumor differentiation grade. Interestingly, the enzyme activity in histologically normal paratumoral tissues was statistically lower than control samples (P < 0.001). As occurs in neoplastic tissues, a relevant mean reduction (P < 0.0001; almost 90%) of alkaline sphingomyelinase was revealed in stool samples from tumor patients when compared with controls. CONCLUSION: These findings may have implications for cancer biology and perhaps also for the design of clinical test, thus suggesting that the fecal sphingomyelinase activity could really reflect the human intestinal mucosa enzyme level and could represent a new marker for human colorectal adenocarcinoma, mainly taking into account its early appearance in intestinal neoplasms.  相似文献   
90.
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