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91.
OBJECTIVE: This study was undertaken to determine the association between genitourinary tract infection with Chlamydia trachomatis and spontaneous preterm birth. STUDY DESIGN: Genitourinary tract infection with C trachomatis was determined with a ligase chain reaction assay of voided urine samples collected at 24 weeks' gestation (22 weeks' to 24 weeks 6 days' gestation) and 28 weeks' gestation (27 weeks' to 28 weeks 6 days' gestation). Case patients (spontaneous preterm birth at <37 weeks' gestation; n = 190) and control subjects (delivery at >/=37 weeks' gestation, matched for race, parity, and center; n = 190) were selected from 2929 women enrolled in the Preterm Prediction Study of the National Institute of Child Health and Human Development Maternal-Fetal Medicine Units Network. RESULTS: Genitourinary C trachomatis infection (11% overall) was significantly more common among the case patients than among the control subjects at 24 weeks' gestation (15.8% vs 6.3%; P =.003) but not at 28 weeks' gestation (12.6% vs 10.9%; P =.61). Women with chlamydia infection were more likely to have bacterial vaginosis (57.1% vs 32.9%; P =.002) and a short cervical length (相似文献   
92.
OBJECTIVE: A cervicovaginal fetal fibronectin value of >/=50 ng/mL has been used to define women at risk of having a preterm birth. We evaluated the relationship between quantitative fetal fibronectin values and spontaneous preterm birth.Study Design: Cervical and vaginal specimens for fetal fibronectin were obtained at 24, 26, 28, and 30 weeks' gestation from 2926 women. Quantitative fetal fibronectin values were calculated by using absorbances determined by enzyme-linked immunosorbent assay. The highest fetal fibronectin value (cervical or vaginal) for each woman at each visit was evaluated in relation to spontaneous preterm birth at <35 weeks' gestation. Receiver operating characteristic curves were constructed to determine the optimal cutoff point for fetal fibronectin values to predict spontaneous preterm birth at <35 weeks' gestation and within 4 weeks of testing. RESULTS: The risk of spontaneous preterm birth increased as a function of increasing fetal fibronectin values from approximately 20 to 300 ng/mL. Fetal fibronectin values > or =300 ng/mL were not associated with a further increase in spontaneous preterm birth. Examination of the receiver operating characteristic curve indicates that the optimal cutoff point for a positive fetal fibronectin test result at 24 to 30 weeks' gestation to predict spontaneous preterm birth at <35 weeks is between 45 and 60 ng/mL. CONCLUSION: Increasing levels of cervicovaginal fetal fibronectin up to 300 ng/mL are associated with an increasing risk of spontaneous preterm birth. Nevertheless, at 24 to 30 weeks, the value currently used, 50 ng of fetal fibronectin per milliliter, appears to be a reasonable cutoff point for predicting spontaneous preterm birth at <35 weeks' gestation.  相似文献   
93.
OBJECTIVE: The purpose of this study was to examine the effects of digital cervical examination on maternal and neonatal outcomes among women with preterm rupture of membranes. STUDY DESIGN: This analysis includes data from a previously reported trial of antibiotic treatment during expectant management of rupture of membranes at 24 to 32 weeks' gestation in singleton and twin gestations. Patients from both the randomized trial (n = 299 in the antibiotic group and n = 312 in the placebo group) and the observational component (n = 183) are included in this analysis. The groups were divided into those with one (n = 161) or two digital cervical examinations (n = 27) and those with no digital cervical examinations (n = 606). RESULTS: The gestational ages at enrollment were similar in the two groups (29 +/- 2 weeks' gestation for one or two examinations vs 29 +/- 2 weeks' gestation for no examinations; P =.85). There were no differences in chorioamnionitis (27% vs 29%; P =.69), endometritis (13% vs 11%; P =.5), or wound infection (0.5% vs 1%; P >.999) between the group with one or two examinations and the no-examination group. Infant outcomes were also similar in the two groups, including early sepsis (6% vs 5%; P =.68), respiratory distress syndrome (51% vs 45%; P =.18), intraventricular hemorrhage (7% vs 7%; P =.67), necrotizing enterocolitis (5% vs 3%; P =.19), and perinatal death (7% vs 5%; P =.45). A composite outcome made up of these neonatal outcomes was not different (56% vs 48%; P =.10) between the group with one or two examinations and the no-examination group. The time from rupture to delivery was shorter in the digital examination group (median value, 3 vs 5 days; P <. 009). Multivariable analysis to adjust for antibiotic study group, group B streptococcal culture status, race, and maternal transfer did not modify these results. CONCLUSION: Performance of one or two digital cervical examinations during the course of expectant management of rupture of membranes between 24 and 32 weeks' gestation was associated with shorter latency but did not appear to worsen either maternal or neonatal outcome.  相似文献   
94.
95.
A 75-year-old native Dutch farmer presented with a painless swelling of his right hand extending into his forearm, accompanied by general malaise and low grade fever. His medical history revealed coxitis tuberculosa in 1954 and injury of the same hand in 1978. His present swelling appeared to be caused by Mycobacterium bovis, probably due to endogenous reactivation. Whether the mycobacteria reached the hand hematogenously or were directly inoculated at the time of injury of his hand in 1978 remains unclear.  相似文献   
96.
银杏叶制剂对心绞痛患者的抗氧化和抗脂质过氧化作用   总被引:15,自引:0,他引:15  
目的:探讨银杏叶制剂对心绞痛患者的抗氧化和抗脂质过氧化作用。方法:检测了78例心绞痛患者经银杏叶制剂“天宝宁”治疗前后的血浆维生素C(P-VC)、维生素E(P-VE)、β-胡萝卜素(P-β-CAR)、过氧化脂质(P-LPO)以及红细胞超氧化物歧化酶(E-SOD)、过氧化氢酶(E-CAT)、谷胱甘肽过氧化物酶(E-GSH-PX)、过氧化脂质(E-LPO)值。结果:与治疗前比较,治疗后的P-VC、P-  相似文献   
97.
To evaluate effects on the fetus and neonate, 53 paracervical blocks were administered to 38 low-risk parturients using a controlled superficial injection of 0.25% bupivacaine. Continuous fetal heart rate monitoring revealed no instance of bradycardia or late deceleration pattern. Apgar scores, cord arterial and venous pH values, and neurobehavioral evaluations of the neonates were similar to those observed in other low-risk patients. The effectiveness of pain relief of the blocks was less than expected or reported by other authors. Although we observed no harmful effects on the fetus or neonate from the superficial paracervical injection of bupivacaine, we did not find this combination of drug and technique to give dependable, effective pain relief in labor.  相似文献   
98.
Percutaneous nephrostolithotomy, which can require a double puncture, is presently the method of choice in our institution for the removal of renal stones. Patients that underwent this procedure were evaluated to identify the possible reasons for the double puncture. Of 200 patients evaluated, 14 needed a second tract. The three variables that determined whether a second puncture was needed, in order of importance, were number and size of the stones, with second tracts needed in patients with multiple stones and staghorn calculi; anatomical variations of the renal collecting system itself, with bifid systems the most significant anatomic variation; and the dexterity of the radiologist in performing the puncture and the ability of the urologist to extract the stone. Second tracts were needed more frequently in patients who presented with stones in both the lower and middle poles of the collecting systems.  相似文献   
99.
Experience with the Amplatz retrievable vena caval filter. Work in progress   总被引:1,自引:0,他引:1  
The Amplatz retrievable vena caval filter was designed in an attempt to decrease complications associated with the placement of Mobin-Uddin or Kimray-Greenfield filters. The design allows percutaneous retrieval, thus expanding application of the filter to situations requiring temporary prophylaxis against pulmonary embolism. Filters have been placed in 16 patients, nine (56%) for prophylactic purposes. All filters were easily inserted percutaneously. Complications occurred in three patients; these included complete thrombosis of the inferior vena cava below the filter, misplacement of one filter into the pericaval retroperitoneal tissue, and development of thrombus cranial to the filter. With the current introduction system, the possibility of filter misplacement has been essentially eliminated. No patient experienced symptoms suggestive of pulmonary embolism after filter insertion. One filter retrieval has been performed, with no complications.  相似文献   
100.
A prospective evaluation of color flow mapping and real-time ultrasound was performed to determine if pseudoaneurysms could be distinguished from other causes of masses surrounding vascular grafts of the lower extremities. Twelve palpable pulsatile masses were imaged. Diagnoses were confirmed at angiography (n = 11), computed tomography (n = 7), aspiration biopsy (n = 5), and operative intervention (n = 6). A swirling pattern of blood flow was seen in six of seven cases of pseudoaneurysm. Lack of flow signals was noted in four of the five collections representing hematoma (n = 2) or infection (n = 2). The seventh case was later shown to be an infected, thrombosed pseudoaneurysm. The single false-positive diagnosis was made early in the series when the flow signals detected were due to transmitted arterial pulsations. The authors conclude that color Doppler flow imaging is useful in the differential diagnosis of pulsatile masses associated with prosthetic grafts. Prosthetic graft pseudoaneurysms have a specific appearance of swirling blood flow arising from a wide neck and are distinguishable from traumatic or iatrogenic pseudoaneurysms of the native vascular tree.  相似文献   
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