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排序方式: 共有2103条查询结果,搜索用时 15 毫秒
21.
0 引言 胰腺多房性潴留性囊肿极为罕见,我科收治1例,报道如下.1 病例报告 患者,男,29岁,因发现右上腹包块11d入院,缘于11d前无明显诱因感右上腹痛,仅局限于右上腹部,无肩背部放散痛,伴间歇性发热,体温最高达38.3℃,经抗炎,对症治疗无效.并逐渐可触及右上腹有一肿块,在当地医院行穿刺检查为脓血性液体.镜检发现炎性细胞,B超示:胆囊窝下方及右肾内侧及腹腔动脉,下腔静脉外前方可见异常区,大小约9.1cm×6.6cm×7.6cm,边界清楚,形态不规则,内呈蜂窝状,可见多个大小不等的液性暗区,CT示:右上腹部上腔静脉前方6.0cm×9.0cm肿块和周围组织粘… 相似文献
22.
INTRODUCTION: Traditional methods of determining blood pressure may be unreliable (auscultation or palpation) or unavailable (direct arterial cannulation) in the air medical environment. The authors investigated the combination of a pulse oximeter with a standard sphygmomanometer (blood pressure) cuff as an alternative method. METHOD: The pulse oximeter is applied to a finger on the same upper extremity on which a standard blood pressure cuff had been applied. A baseline blood pressure was obtained by palpation or an automated blood pressure device. One minute later, the systolic blood pressure (SBP) was determined by inflating the blood pressure cuff until the pulsatile display on the pulse oximeter was obliterated. This was taken as the systolic blood pressure. RESULTS: Complete data were obtained on 116 patients, with 223 data pairs. The SBP as obtained by the baseline method was strongly correlated with the SBP obtained by the pulse oximeter display obliteration method (r = 0.90, p < 0.001). CONCLUSION: The obliteration of the wave form display on a pulse oximeter is an accurate, convenient, inexpensive and readily available alternative method of determining SBP. 相似文献
23.
A young boy presented with an uncommon finding of impaction of upper right central incisor and transposition of canine and lateral incisor on the same side. Esthetic management of his cosmetic problem which included fixed appliance therapy followed by light cure restorations is discussed.KEY WORDS: Impaction, Transposition 相似文献
24.
Effects of tourniquet compression on neuromuscular function 总被引:2,自引:0,他引:2
Mohler LR Pedowitz RA Lopez MA Gershuni DH 《Clinical orthopaedics and related research》1999,(359):213-220
Neuromuscular function in New Zealand White rabbits was evaluated after thigh tourniquet compression in the directly compressed quadriceps muscles and the distal tibialis anterior by measuring isometric contractile function after supramaximal stimulation of the motor nerve. Tourniquet compression resulted in markedly decreased force production beneath and distal to the tourniquet. Two days after compression, maximal quadriceps force production was decreased to 46% of control values with 125 mm Hg compression and 21% of control values after 350 mm Hg compression. Maximum tibialis anterior force production declined to 70% of control values after 125 mm Hg thigh compression and 24% of control values after 350 mm Hg thigh compression. Functional deficits were greater in the directly compressed quadriceps muscles, but the quadriceps and tibialis anterior had significantly increased impairment when the tourniquet inflation pressure was increased from 125 mm Hg to 350 mm Hg. Three weeks after compression, quadriceps function had returned to 94% of control value after 125 mm Hg compression and 83% after 350 mm Hg. Tibialis anterior function returned to 88% of control values after 125 mm Hg thigh compression and 83% after 350 mm Hg. Clinically, the use of lower inflation pressures may minimize the complications of tourniquet use and enhance postoperative recovery. 相似文献
25.
S R Mohler 《Aviation, space, and environmental medicine》1976,47(3):238-247
A multiplicative and additive formula has been developed for assisting in the development of schedules for airline pilots and flight engineers. The formula is based on freshness/tiredness data derived from aircrews on world flights. It should materially assist those who develop the schedules to avoid, where possible, finalizing those crew patterns that would impose a severe physiologic load on cockpit personnel. The objective of the application of the formula is to assure that crew members retain adequate "physiologic reserve" in the course of flying various segments of a pattern. This enables them to absorb the stresses of schedule delays or disruptions, as well as unforeseen operational problems and flight emergencies. 相似文献
26.
27.
Isolation and characterization of propagable cell lines (HUNC) from the androgen-sensitive Dunning R3327H rat prostatic adenocarcinoma 总被引:1,自引:0,他引:1
Presnell SC; Borchert KM; Glover WJ; Gregory CW; Mohler JL; Smith GJ 《Carcinogenesis》1998,19(4):585-590
The Dunning H rat prostate tumor (R3327H) is a widely used experimental
model of human prostatic adenocarcinoma (CaP). The Dunning H tumor has been
characterized as androgen-sensitive, androgen-receptor (AR) positive,
prostate-specific antigen and prostatic acid phosphatase (PAP) positive. To
date, the tumor has been maintained by serial passage in vivo because of
the lack of an in vitro cell line that retains the characteristics of the
in vivo tumor. The objective of the present study was to establish a
propagable cell line from R3327H adenocarcinoma that maintained androgen
sensitivity and expression of AR, PSA and PAP. Tissue harvested from an in
vivo R3327H tumor was dissociated with collagenase and placed into
Richter's improved media (with supplements). A cytokeratin-positive
epithelial cell line (HUNC- E) and a vimentin-positive stromal cell line
(HUNC-S) were generated from the primary culture, subcultured continuously
for >300 days, and passaged >50 times. Survival of the HUNC-E cell
line in vitro depended on several media supplements, including
nicotinamide, insulin, transferrin, selenium and epidermal growth factor
(EGF). HUNC-E cells expressed AR and produced PSA and PAP throughout the
culture period, as confirmed by immunocytochemistry and Western blot
analyses. Addition of 14 nM testosterone (T) or dihydrotestosterone (DHT)
to HUNC-E cells, stimulated DNA synthesis as well as anchorage-independent
growth and PSA production, which demonstrated the androgen-sensitive nature
of the cells in vitro. When HUNC-E and HUNC-S cells were combined in a 3:1
ratio and introduced subcutaneously into syngeneic male hosts, tumors
formed in 2/3 animals with an average latency of 7 months. RT-PCR and
immunocytochemical characterization of the HUNC cell lines revealed that
the cells expressed several growth factors and their cognate receptors,
including HGF, TGF-alpha and the TGF-betas, indicating the establishment of
potential autocrine loops in the neoplastic cells. The HUNC-E and HUNC-S
CaP cell lines, which retain the characteristics of the epithelial and
stromal components of the in vivo R3327H tumor, will allow a more thorough
and informative molecular and biological analysis of prostatic
adenocarcinoma.
相似文献
28.
Previous work has shown that sustained increased and decreased cell
proliferation, induced by dietary zinc deficiency and caloric restriction
respectively, influence the course of N- nitrosomethylbenzylamine
(NMBA)-induced esophageal carcinogenesis in rats. The present study
considered whether the increased cell proliferation and esophageal tumor
incidence induced by zinc deficiency are reversed upon zinc replenishment.
Weanling rats were maintained initially on a deficient diet containing 4
p.p.m. zinc. After 5 weeks, carcinogen-treated animals were given six
intragastric doses of NMBA (2 mg/kg twice weekly). Controls were untreated.
After the second NMBA dose, the rats were divided into three dietary
groups. One group was continued on the deficient diet, while the other two
groups were switched to diets containing either 75 or 200 p.p.m. zinc, with
half of the members in each group fed ad libitum and half pair-fed with
deficient rats. NMBA-untreated controls were similarly replenished. At
various time points, esophageal cell proliferation was assessed in five
animals from each group by immunohistochemical detection of cells in S
phase, with in vivo 5-bromo-2'deoxyuridine labeling. At 11 weeks after the
first dose, esophageal tumor incidence was greatly reduced, from 100% in
the deficient group to 26 and 14% respectively in the replenished groups
fed ad libitum 75 and 200 p.p.m. zinc and to 14 and 11% respectively in the
replenished groups pair-fed 75 and 200 p.p.m. zinc. In addition, the number
of tumors per esophagus was reduced from 9.93 +/- 4.25 in deficient rats,
to a range of 0.11 +/- 0.31-0.30 +/- 0.54 in replenished animals. Following
zinc replenishment, esophageal cell proliferation, as measured by labeling
index (LI), the number of labeled cells and the total number of cells, was
markedly decreased in NMBA-untreated and -treated esophagi as compared with
those in corresponding deficient esophagi. Thus, the esophageal cell
proliferation induced by zinc deficiency is reversed by zinc replenishment
and replenished animals have a markedly lower incidence of esophageal
tumors.
相似文献
29.
Mark A Titus Christopher W Gregory O Harris Ford Michael J Schell Susan J Maygarden James L Mohler 《Clinical cancer research》2005,11(12):4365-4371
PURPOSE: Prostate cancer recurs during androgen deprivation therapy despite reduced circulating androgens. We showed that recurrent prostate cancer tissue has testosterone levels similar to androgen-stimulated benign prostate, whereas dihydrotestosterone levels were reduced 82% to 1.45 nmol/L, sufficient for androgen receptor activation. The altered testosterone/dihydrotestosterone ratio in recurrent prostate cancer suggests loss of 5alpha-reducing capability. The aim of this study was to characterize steroid 5alpha-reductase isozymes I (S5alphaRI) and II (S5alphaRII) in prostate tissues. EXPERIMENTAL DESIGN: A tissue microarray was constructed from 22 recurrent prostate cancer specimens and matched pairs of androgen-stimulated benign prostate and androgen-stimulated prostate cancer from 23 radical prostatectomy specimens. Immunoblots were constructed from eight recurrent prostate cancers, eight androgen-stimulated benign prostate, and eight androgen-stimulated prostate cancer specimens. Isozyme expression was examined in microarray sections and immunoblots using S5alphaRI and S5alphaRII polyclonal antibodies. Isozyme activities were measured in 12 recurrent prostate cancer, 12 androgen-stimulated benign prostate, and 12 androgen-stimulated prostate cancer specimens. RESULTS: Nuclear immunostaining exhibited higher S5alphaRI expression than S5alphaRII in recurrent prostate cancer, androgen-stimulated benign prostate, and androgen-stimulated prostate cancers (P < 0.0001); mean expression was 125, 150, and 115 for S5alphaRI versus 10, 29, and 37 for S5alphaRII, respectively. Cytoplasmic immunostaining was moderate and similar for both isozymes in the three tissue types (P > 0.05). Immunoblots confirmed immunohistochemistry; S5alphaRI was expressed in recurrent prostate cancer specimens and S5alphaRII was not detected. The activity of S5alphaRI (114.4 pmol/mg epithelial protein/minute) was 3.7-fold higher than S5alphaRII (30.7 pmol/mg epithelial protein/minute) in recurrent prostate cancer specimens. CONCLUSIONS: Expression levels and isozyme activity shifts from S5alphaRII toward S5alphaRI in recurrent prostate cancer. Dual inhibition of S5alphaRI and S5alphaRII should reduce dihydrotestosterone biosynthesis and may prevent or delay growth of recurrent prostate cancer. 相似文献
30.
Mohler CR Nordt SP Williams SR Manoguerra AS Clark RF 《Annals of emergency medicine》2000,35(3):239-244
STUDY OBJECTIVE: To determine whether pediatric patients with acute, mild to moderate acetaminophen exposures, treated with home monitoring alone, develop systemic signs of hepatic injury. METHODS: A prospective, observational study of calls to a regional poison center over a 25-month period was performed. Patients were eligible for the study if they were younger than 7 years and had an acute maximum possible acetaminophen exposure of up to 200 mg/kg. Exclusion criteria included previous decontamination measures, possibility of ingestion of an extended-release preparation, health or medication issues that could increase susceptibility to hepatotoxicity, current symptoms of hepatotoxicity, and indeterminable ingestions. Study protocol included reviewing the signs and symptoms of early and late acetaminophen toxicity, a 4- to 6-hour follow-up call, and a 72-hour follow-up call. Outcome measures were defined as a verbal report by the patient's parent or guardian of the presence or absence of signs or symptoms of hepatotoxicity. RESULTS: A total of 1,039 patients were enrolled in the study, including 519 girls and 520 boys, with exposures ranging from 20 to 200 mg/kg. Eighteen patients were lost to follow-up; data were incomplete for 2 patients. At 72-hour follow-up, the remaining 1,019 patients were all doing well, without signs or symptoms of hepatotoxicity. CONCLUSION: On the basis of these data, pediatric patients with acute acetaminophen exposures of up to 200 mg/kg, treated with home monitoring alone, do not develop signs or symptoms of hepatic injury. 相似文献